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{{Short description|Joint abnormality}}
{{dablink|This article describes hip dysplasia in humans. For hip dysplasia in animals, see [[Hip dysplasia (canine)]].}}
{{About|the disease in humans|the disease in dogs|Canine hip dysplasia}}
{{Infobox disease
{{Use dmy dates|date=July 2019}}
| Name = Hip dysplasia (human)
{{Infobox medical condition (new)
| Image = Congenitaldislocation10.JPG
| name = Hip dysplasia
| Caption = Congenital dislocation of the left hip in an elderly person. Closed arrow marks the acetabulum, open arrow the femoral head.
| synonyms = Developmental dysplasia of the hip (DDH),<ref name=OA2013/> developmental dislocation of the hip,<ref name=OA2013/> congenital dysplasia of the hip (CDH)<ref name=Dictionary>{{cite web |url=http://cancerweb.ncl.ac.uk/cgi-bin/omd?congenital+dysplasia+of+the+hip |title=Definition: congenital dysplasia of the hip from Online Medical Dictionary }}{{dead link|date=September 2019}}</ref>
| DiseasesDB = 3056
| ICD10 = {{ICD10|Q|65||q|65}}
| image = Congenitaldislocation10.JPG
| caption = Congenital dislocation of the left hip in an elderly person. Closed arrow marks the acetabulum, open arrow the femoral head.
| ICD9 = {{ICD9|754.3}}
| ICDO =
| pronounce =
| OMIM = 142700
| field = [[Pediatrics]], [[orthopedics]]
| symptoms = None, hip aches, one leg shorter, limping<ref name=OA2013/>
| MedlinePlus = 000971
| complications = [[Arthritis]]<ref name=Shaw2017/>
| eMedicineSubj = orthoped
| onset =
| eMedicineTopic = 456
| MeshID = D006618
| duration =
| types =
| causes =
| risks = Family history, [[swaddling]], [[breech birth]]<ref name=Shaw2017/>
| diagnosis = [[Physical exam]], [[ultrasound]]<ref name=Shaw2017/>
| differential =
| prevention =
| treatment = [[orthotics|Bracing]], [[orthopedic casting|casting]], [[surgery]]<ref name=Shaw2017/>
| medication =
| prognosis = Good (if detected early)<ref name=OA2013/>
| frequency = 1 in 1,000 (term babies)<ref name=Shaw2017/>
| deaths =
}}
}}
<!-- Definition and symptoms -->
'''Hip dysplasia''' is an abnormality of the [[hip joint]] where the socket portion does not fully cover the ball portion, resulting in an increased risk for [[joint dislocation]].<ref name="OA2013">{{Cite web |date=October 2013 |title=Your Orthopaedic Connection: Developmental Dysplasia of the Hip |url=http://orthoinfo.aaos.org/topic.cfm?topic=A00347 |website=American Academy of Orthopaedic Surgeons}}</ref> Hip dysplasia may occur at birth or develop in early life.<ref name=OA2013/> Regardless, it does not typically produce symptoms in babies less than a year old.<ref name=Shaw2017/> Occasionally one leg may be shorter than the other.<ref name=OA2013/> The left hip is more often affected than the right.<ref name=Shaw2017/> Complications without treatment can include [[arthritis]], limping, and [[low back pain]].<ref name=Shaw2017>{{cite journal|last1=Shaw|first1=BA|last2=Segal|first2=LS|last3=SECTION ON|first3=ORTHOPAEDICS.|title=Evaluation and Referral for Developmental Dysplasia of the Hip in Infants.|journal=Pediatrics|date=December 2016|volume=138|issue=6|pages=e20163107|pmid=27940740|doi=10.1542/peds.2016-3107|doi-access=free}}</ref> Females are affected more often than males.<ref name=OA2013/>
<!-- Cause and diagnosis -->
Risk factors for hip dysplasia include female sex, family history, certain [[swaddling]] practices, and [[breech birth|breech presentation]] whether an infant is delivered vaginally or by cesarean section.<ref name=Shaw2017/> If one [[identical twin]] is affected, there is a 40% risk the other will also be affected.<ref name=Shaw2017/> Screening all babies for the condition by [[physical examination]] is recommended.<ref name=Shaw2017/> [[Ultrasonography]] may also be useful.<ref name=Shaw2017/>


<!-- Prevention and treatment -->
'''Hip dysplasia''', '''developmental dysplasia of the [[hip]] (DDH)'''<ref name="urlYour Orthopaedic Connection: Developmental Dysplasia of the Hip">{{cite web |url=http://orthoinfo.aaos.org/topic.cfm?topic=A00347 |title=Your Orthopaedic Connection: Developmental Dysplasia of the Hip |format= |work=}}</ref> or '''congenital dysplasia of the [[hip]] (CDH)'''<ref name="urlDefinition: congenital dysplasia of the hip from Online Medical Dictionary">{{cite web |url=http://cancerweb.ncl.ac.uk/cgi-bin/omd?congenital+dysplasia+of+the+hip |title=Definition: congenital dysplasia of the hip from Online Medical Dictionary |format= |work=}}</ref> is a [[congenital]] or acquired deformation or misalignment of the [[hip joint]].
Many of those with mild instability resolve without specific treatment.<ref name=Shaw2017/> In more significant cases, if detected early, [[orthotics|bracing]] may be all that is required.<ref name=Shaw2017/> In cases that are detected later, surgery and [[orthopedic casting|casting]] may be needed.<ref name=Shaw2017/> About 7.5% of [[hip replacements]] are done to treat problems which have arisen from hip dysplasia.<ref name=Shaw2017/>


<!-- Epidemiology -->
==Terminology==
About 1 in 1,000 babies have hip dysplasia.<ref name=Shaw2017/> Hip instability of meaningful importance occurs in one to two percent of babies born at term.<ref name=Shaw2017/> Females are affected more often than males.<ref name=OA2013/> Hip dysplasia was described at least as early as the 300s BC by [[Hippocrates]].<ref>{{cite book|last1=Bentley|first1=George|title=European Instructional Lectures: Volume 9, 2009; 10th EFORT Congress, Vienna, Austria|date=2009|publisher=Springer Science & Business Media|isbn=9783642009662|page=40|url=https://books.google.com/books?id=T0d7JhHMlf0C&pg=PA40|language=en}}</ref>
Some sources prefer "developmental dysplasia of the hip" (DDH) to "congenital dislocation of the hip" (CDH), finding the latter term insufficiently flexible in describing the diversity of potential complications.<ref name="urlDevelopmental Dysplasia of the Hip - October 15, 2006 -- American Family Physician">{{cite web |url=http://www.aafp.org/afp/20061015/1310.html |title=Developmental Dysplasia of the Hip - October 15, 2006 -- American Family Physician |work=}}</ref>
{{TOC limit|3}}


==Signs and symptoms==
The use of the word congenital can also imply that the condition already exists at birth. This terminology introduces challenges, because the joint in a newborn is formed from [[cartilage]] and still [[malleable]], making the onset difficult to ascertain.
[[File:Hip dysplasia - schematic.jpg|thumb|right|400px|Types of misalignments of femur head to socket in hip dysplasia. A: Normal. B: Dysplasia. C: Subluxation. D: Luxation]]
Hip dysplasia can range from barely detectable to severely malformed or dislocated.
The [[Congenital disorder|congenital]] form, [[teratology|teratologic]] or non-reducible dislocation occurs as part of more complex conditions.{{citation needed|date=October 2020}}


The condition can be bilateral or unilateral:
The newer term DDH also encompasses [[occult]] dysplasia (e.g. an underdeveloped [[joint]]) without [[Joint dislocation|dislocation]] and dislocation developing after the "[[Infant|newborn]]" phase.
* If both hip joints are affected, one speaks of "bilateral" dysplasia. In this case, some diagnostic indicators like asymmetric folds and leg-length inequality do not apply.
* In unilateral dysplasia only one joint shows deformity, the opposite side may show resulting effects.<ref name="pmid16721954">{{cite journal |vauthors=Jacobsen S, Rømer L, Søballe K |title=The other hip in unilateral hip dysplasia |journal=[[Clin. Orthop. Relat. Res.]] |volume=446 |pages=239–46 |year=2006 |pmid=16721954 |doi=10.1097/01.blo.0000201151.91206.50|s2cid=11709860 }}</ref> In the majority of unilateral cases, the left hip has the dysplasia.
If the joint is fully dislocated a false acetabulum often forms (often higher up on the pelvis) opposite the dislocated femoral head position.


In acetabular dysplasia, the [[acetabulum]] (socket) is too shallow or deformed. The center-edge angle is measured as described by Wiberg.<ref>Wiberg G. Studies of acetabular and congenital subluxation of the hip joint with special reference to complication of osteoarthritis Acta Chir Scand 1939, 83(Suppl. 58)</ref> Two forms of femoral dysplasia are [[coxa vara]], in which the [[femur head]] grows at too narrow an angle to the shaft, and [[coxa valga]], in which the angle is too wide.
The term is not used consistently. In pediatric/neonatal orthopedics it is used to describe unstable/dislocatable hips and poorly developed acetabula. For adults it describes hips showing abnormal femur head or acetabular x-rays.<ref>[http://faculty.washington.edu/momus/PB/ddh.htm Dr. Rose's Peripheral Brain-DEVELOPMENTAL DYSPLASIA OF THE HIP<!-- Bot generated title -->]</ref><ref name=autogenerated1>[http://www.aafp.org/afp/990700ap/177.html Screening for Developmental Dysplasia of the Hip - July 1999 - American Academy of Family Physicians<!-- Bot generated title -->]</ref>


A rare type, the "Beukes familial hip dysplasia" is found among [[Afrikaners]] that are members of the Beukes family. The femur head is flat and irregular. People develop osteoarthritis at an early age.<ref name="pmid2389793">{{cite journal |vauthors=Cilliers HJ, Beighton P |title=Beukes familial hip dysplasia: an autosomal dominant entity |journal=[[Am. J. Med. Genet.]] |volume=36 |issue=4 |pages=386–90 |year=1990 |pmid=2389793 |doi=10.1002/ajmg.1320360403}}</ref>
Some sources prefer the term "hip dysplasia" over DDH, considering it to be "simpler and more accurate", partly because of the redundancy created by the use of the terms [[developmental]] and [[dysplasia]].<ref name="urleMedicine - Developmental Dysplasia of the Hip : Article by James McCarthy, MD, FAAOS">{{cite web |url=http://www.emedicine.com/orthoped/topic456.htm |title=eMedicine - Developmental Dysplasia of the Hip : Article by James McCarthy, MD, FAAOS |work=}}</ref>
'''TYPES OF DDH''' include subluxation,dysplasia,and dislocation.The main types are the result of either laxity of the supporting capsule or an abnormal acetabulum.


==Causes==
==Forms of the condition==
Hip dysplasia is considered to be a [[multifactorial inheritance|multifactorial]] condition. That means that several factors are involved in causing the condition to manifest.<ref>Lynn T Staheli, Fundamentals of Pediatric Orthopedics, p 13</ref>
[[Image:Hip dysplasia - schematic.jpg|thumb|right|400px|Types of misalignments of femur head to socket in hip dysplasia. A: Normal. B: Dysplasia. C: Subluxation. D: Luxation]]
Hip dysplasia can range from barely detectable to severely malformed / dislocated.
The [[Congenital disorder|congenital]] form, [[teratology|teratologic]] or non-reducible dislocation occurs as part of more complex conditions.


The cause of the condition is unknown; however, some factors of congenital hip dislocation are through heredity and racial background. It is also thought that the higher rates in some ethnic groups (such as some Native American groups) is due to the practice of swaddling of infants, which is known to be a potential risk factor for developing dysplasia. It also has a low risk in [[African Americans]] and southern [[Chinese people|Chinese]].{{citation needed|date=December 2017}}
The condition can be bilateral or unilateral:
* If both hip joints are affected one speaks of "bilateral" dysplasia. In this case some diagnostic indicators like asymmetric folds and leg-length inequality do not apply.
* In unilateral dysplasia only one joint shows deformity, the contralateral side may show resulting effects.<ref name="pmid16721954">{{cite journal |author=Jacobsen S, Rømer L, Søballe K |title=The other hip in unilateral hip dysplasia |journal=[[Clin. Orthop. Relat. Res.]] |volume=446 |issue= |pages=239–46 |year=2006 |pmid=16721954 |doi=10.1097/01.blo.0000201151.91206.50}}</ref> In the majority of unilateral cases the left hip has the dysplasia.
If the joint is fully dislocated a false acetabulum often forms (often higher up on the pelvis) opposite the dislocated femoral head position.


===Congenital===
In actetabular dysplasia the [[acetabulum]] (socket) is too shallow or deformed. The center-edge angle is measured as described by Wiberg.<ref>Wiberg G. Studies of acetabular and congenital subluxation of the hip joint with special reference to complication of osteoarthritis Acta Chir Scand 1939, 83(Suppl. 58)</ref> In [[coxa vara]] the [[femur head]] grows at too narrow an angle to the shaft, in [[coxa valga]] the angle is too wide.
Some studies suggest a hormonal link.<ref name=autogenerated2 /> Specifically, the hormone [[relaxin]] has been indicated.<ref name="pmid9128773">{{cite journal |vauthors=Forst J, Forst C, Forst R, Heller KD |title=Pathogenetic relevance of the pregnancy hormone relaxin to inborn hip instability |journal=Arch Orthop Trauma Surg |volume=116 |issue=4 |pages=209–12 |year=1997 |pmid=9128773 |doi= 10.1007/BF00393711|s2cid=32322656 }}</ref>


Female sex, alone without other known risk factors, accounts for 75%.<ref name=aap/> A genetic factor is indicated since the trait runs in families and there is an increased occurrence in some ethnic populations (e.g., [[Native Americans in the United States|Native Americans]],<ref>{{cite web|last1=Morcuende|first1=Jose A.|last2=Weinstein|first2=Stuart L.|date=|title=Developmental dysplasia of the hip: natural history, results of treatment, and controversies. In: Bourne R, ed. Controversies in Hip Surgery.|url=http://fds.oup.com/www.oup.co.uk/pdf/0-19-263161-6.pdf|url-status=dead|archive-url=https://web.archive.org/web/20110726005636/http://fds.oup.com/www.oup.co.uk/pdf/0-19-263161-6.pdf|archive-date=26 July 2011|publisher=Oxford University Press}}</ref> [[Sami people]]<ref>[https://archive.today/20121217192358/http://www3.interscience.wiley.com/cgi-bin/abstract/110503598 The occurrence of hip joint dislocation in early Lappic populations of Norway], Per Holck, Anthropological Department, Anatomical Institute, Box 1105 Blindern, N-0317 Oslo 3, Norway</ref><ref name="pmid11077514">{{cite journal |author=Forsdahl A |title=[A physician from Finnmark who pointed out the significance of heredity in congenital hip dysplasia] |language=no |journal=[[Journal of the Norwegian Medical Association|Tidsskr. Nor. Legeforen.]] |volume=120 |issue=22 |pages=2672–3 |year=2000 |pmid=11077514 }}</ref>). A locus has been described on [[chromosome 13]].<ref name="pmid16773577">{{cite journal |vauthors=Mabuchi A, Nakamura S, Takatori Y, Ikegawa S |title=Familial osteoarthritis of the hip joint associated with acetabular dysplasia maps to chromosome 13q |journal=[[Am. J. Hum. Genet.]] |volume=79 |issue=1 |pages=163–8 |year=2006 |pmid=16773577 |doi=10.1086/505088 |pmc=1474113}}</ref> Beukes familial dysplasia, on the other hand, was found to [[Genetic mapping|map]] to an 11-cM region on chromosome 4q35, with [[Penetrance|nonpenetrant]] carriers not affected.<ref>{{cite web|url=http://www.ajhg.org/AJHG/fulltext/S0002-9297(07)61731-5|archive-url=https://web.archive.org/web/20080506142503/http://www.ajhg.org/AJHG/fulltext/S0002-9297(07)61731-5|url-status=dead|archive-date=6 May 2008|title=AJHG - Autosomal Dominant (Beukes) Premature Degenerative Osteoarthropathy of the Hip Joint Maps to an 11-cM Region on Chromosome 4q35|date=6 May 2008}}</ref> Further risk factors include, gender, genetics (family history),<ref>{{cite journal |last1=Hashmi |first1=Jamil |last2=Basit |first2=Sulman |last3=Khoshhal |first3=Khalid |title=Genetics of developmental dysplasia of the hip: Recent progress and future perspectives |journal=Journal of Musculoskeletal Surgery and Research |date=August 2019 |volume=3 |issue=3 |doi=10.4103/jmsr.jmsr_46_19 |page=245|s2cid=199547368 |doi-access=free }}</ref><ref name="Causes of DDH">{{cite web|title=Causes of Developmental Dysplasia of the Hip - International Hip Dysplasia Institute|date=13 April 2020|url=http://www.hipdysplasia.org/developmental-dysplasia-of-the-hip/causes-of-ddh/}}</ref> and firstborns.<ref name="urlDevelopmental Dislocation of the Hip - Wheeless Textbook of Orthopaedics">{{cite web |url=http://www.wheelessonline.com/ortho/developmental_dislocation_of_the_hip |title=Developmental Dislocation of the Hip - Wheeless' Textbook of Orthopaedics |date=22 July 2020 }}</ref>
A rare type, the "Beukes familial hip dysplasia" is found among Afrikaners that are members of the Beukes family. The femur head is flat and irregular. Sufferers develop osteoarthritis at an early age.<ref name="pmid2389793">{{cite journal |author=Cilliers HJ, Beighton P |title=Beukes familial hip dysplasia: an autosomal dominant entity |journal=[[Am. J. Med. Genet.]] |volume=36 |issue=4 |pages=386–90 |year=1990 |pmid=2389793 |doi=10.1002/ajmg.1320360403}}</ref>


===Acquired===
==Crowe classification==
In the [[breech birth|breech position]] the femoral head tends to get pushed out of the socket and the breech position is probably the most important single risk factor, whether an infant is delivered vaginally or by cesarean section.<ref name=Shaw2017/>


As an acquired condition it has been linked to traditions of [[swaddling]] infants,<ref name="pmid18166571">{{cite journal |vauthors=Mahan ST, Kasser JR |title=Does swaddling influence developmental dysplasia of the hip? |journal=[[Pediatrics (journal)|Pediatrics]] |volume=121 |issue=1 |pages=177–8 |year=2008 |pmid=18166571 |doi=10.1542/peds.2007-1618 |s2cid=37598276 |url=http://pediatrics.aappublications.org/cgi/pmidlookup?view=long&pmid=18166571}}</ref> use of overly restrictive baby seats, carriers and other methods of transporting babies,<ref name="IHDI Educational Statement">{{cite web|title=Baby Carriers, Seats, & Other Equipment - International Hip Dysplasia Institute|url=http://www.hipdysplasia.org/developmental-dysplasia-of-the-hip/prevention/baby-carriers-seats-and-other-equipment/|access-date=25 June 2012|archive-date=18 November 2020|archive-url=https://web.archive.org/web/20201118081342/https://hipdysplasia.org/developmental-dysplasia-of-the-hip/prevention/baby-carriers-seats-and-other-equipment/|url-status=dead}}</ref> or use of a [[cradle board]] which locks the hip joint in an "adducted" position (pulling the knees together tends to pull the heads of the femur bone out of the sockets or acetabulae) for extended periods. Modern swaddling techniques, such as the 'hip healthy swaddle' have been developed to relieve stress on hip joints caused by traditional swaddling methods.<ref name="Hip-Healthy Swaddling">{{cite web|title=Hip-Healthy Swaddling - International Hip Dysplasia Institute|date=28 May 2020|url=http://www.hipdysplasia.org/developmental-dysplasia-of-the-hip/hip-healthy-swaddling/}}</ref>
In 1979 Dr. John F. Crowe <ref>http://www.onsmd.com/Jon-F-Crowe-MD</ref> et al. proposed a classification to define the degree of malformation and dislocation. Grouped from least severe Crowe I dysplasia to most severe Crowe IV.<ref name="pmid365863">{{cite journal |author=Crowe JF, Mani VJ, Ranawat CS |title=Total hip replacement in congenital dislocation and dysplasia of the hip |journal=[[J Bone Joint Surg Am]] |volume=61 |issue=1 |pages=15–23 |year=1979 |pmid=365863 |doi=}}</ref> This classification is very useful for studying treatment results.


A narrow uterus also facilitates hip joint dislocation during fetal development and birth.{{citation needed|date=October 2020}}
''Rather than using the Wiberg angle because it makes it difficult to quantify the degree of dislocation they used 3 key elements to determine the degree of [[subluxation]]: A reference line at the lower rim of the "teardrop", junction between the femoral head and neck of the respective joint and the height of the pelvis (vertical measurement). They studied [[anteroposterior]] pelvic x-rays and drew horizontal lines through the lower rim of a feature called "teardrop". The distance between this line and the middle lines of the junction between femur head and neck gave them a measure of the degree of femur head subluxation. They further established that a "normal" diameter of the femur head measures 20% of the height of the pelvis. If the middle line of the neck-head junction was more than 10% of the pelvis height above the reference line they considered the joint to be more than 50% dislocated.
''


==Screening and diagnosis==
The following types resulted:
[[File:Hip dysplasia ultrasound.svg|thumb|α and β angles used in hip ultrasound]]
{| class="wikitable"
[[File:Ultrasound Scan ND 0114142455 1429140 crop.png|thumb|Hip ultrasound]]
| '''Class''' || '''Description''' || '''Dislocation'''
[[File:Dislocated hip.jpg|thumb|X-Ray Image showing hip dysplasia in a baby]]
|-
All newborns should be screened for congenital hip dysplasia. The [[Screening (medicine)|screening]] examination techniques to detect hip dysplasia in newborns include observation for
| Crowe I || Femur and acetabulum show minimal abnormal development. || Less than 50% dislocation
* asymmetry of legs and asymmetrical [[gluteal fold]]s ,<ref name="Symptoms of DDH in Children">{{cite web |title=Asymmetry Symptoms of DDH |url=http://www.hipdysplasia.org/developmental-dysplasia-of-the-hip/infant-signs-and-symptoms/asymmetry/ |access-date=31 August 2012 |archive-date=25 October 2020 |archive-url=https://web.archive.org/web/20201025111725/https://hipdysplasia.org/developmental-dysplasia-of-the-hip/infant-signs-and-symptoms/asymmetry/ |url-status=dead }}</ref>
|-
* limb length discrepancy (evaluated by placing the child in a supine position with the hips and knees flexed [unequal knee heights might be noticed – the Galeazzi sign]), and
| Crowe II || The acetabulum shows abnormal development.|| 50% to 75% dislocation
* restricted hip abduction.
|-
Sometimes during an exam a "click" or more precisely "clunk" in the hip may be detected<ref name="urlHipDysplasia - Newborn Nursery at LPCH - Stanford University School of Medicine">{{cite web |url=http://newborns.stanford.edu/HipDysplasia.html |title=HipDysplasia - Newborn Nursery at LPCH - Stanford University School of Medicine |date=5 July 2023 }}</ref> (although not all clicks indicate hip dysplasia).<ref name="pmid15977515">{{cite journal |vauthors=Kamath S, Bramley D |title=Is 'clicky hip' a risk factor in developmental dysplasia of the hip? |journal=[[Scott Med J]] |volume=50 |issue=2 |pages=56–8 |year=2005 |pmid=15977515 |doi=10.1177/003693300505000205|s2cid=23000620 }}</ref> When a hip click (also known as "clicky hips" in the UK) is detected, the child's hips are tracked with additional screenings<ref name="Newborn Screening and Prevention">{{cite web|title=Newborn Screening and Prevention - International Hip Dysplasia Institute|url=http://www.hipdysplasia.org/for-physicians/pediatricians-and-primary-care-providers/newborn-screening-and-prevention/|access-date=31 August 2012|archive-date=12 November 2020|archive-url=https://web.archive.org/web/20201112041651/https://hipdysplasia.org/for-physicians/pediatricians-and-primary-care-providers/newborn-screening-and-prevention/|url-status=dead}}</ref> to determine if developmental dysplasia of the hip is caused.<ref name="Hip Clicks">{{cite web|title=Hip Clicks and Hip Dysplasia - International Hip Dysplasia Institute|url=http://www.hipdysplasia.org/developmental-dysplasia-of-the-hip/infant-signs-and-symptoms/hip-click/|access-date=31 August 2012|archive-date=4 December 2020|archive-url=https://web.archive.org/web/20201204022707/https://hipdysplasia.org/developmental-dysplasia-of-the-hip/infant-signs-and-symptoms/hip-click/|url-status=dead}}</ref> However, new UK guidelines published in April 2021 have stated that isolated clicks are no longer considered clinically significant and therefore do not meet the screen positive criteria.<ref>{{Cite web |title=Newborn and infant physical examination (NIPE) screening programme handbook |url=https://www.gov.uk/government/publications/newborn-and-infant-physical-examination-programme-handbook/newborn-and-infant-physical-examination-screening-programme-handbook#screening-examination-of-the-hips |access-date=2024-10-18 |website=GOV.UK |language=en}}</ref>
| Crowe III || The acetabula is developed without a roof. A false acetabulum develops opposite the dislocated femur head position. The joint is fully dislocated. || 75% to 100% dislocation
|-
| Crowe IV || The acetabulum is insufficiently developed. Since the femur is positioned high up on the pelvis this class is also known as "high hip dislocation". || 100% dislocation
|}


Two maneuvers commonly employed for diagnosis in neonatal exams are the [[Ortolani maneuver]] and the [[Barlow maneuver]].<ref name="Physical Examination of Infants">{{cite web|title=Physical Examination of Infants - International Hip Dysplasia Institute|url=http://www.hipdysplasia.org/for-physicians/pediatricians-and-primary-care-providers/infant-examination/|access-date=31 August 2012|archive-date=20 October 2020|archive-url=https://web.archive.org/web/20201020222943/https://hipdysplasia.org/for-physicians/pediatricians-and-primary-care-providers/infant-examination/|url-status=dead}}</ref><ref>{{cite journal|author=French LM, Dietz FR|last2=Dietz|date=July 1999|title=Screening for developmental dysplasia of the hip|url=http://www.aafp.org/link_out?pmid=10414637|journal=American Family Physician|volume=60|issue=1|pages=177–84, 187–8|pmid=10414637}}</ref>
==Incidence==
Determining the incidence can be difficult.<ref name="pmid9917445">{{cite journal |author=Bialik V, Bialik GM, Blazer S, Sujov P, Wiener F, Berant M |title=Developmental dysplasia of the hip: a new approach to incidence |journal=[[Pediatrics (journal)|Pediatrics]] |volume=103 |issue=1 |pages=93–9 |year=1999 |pmid=9917445 |doi= 10.1542/peds.103.1.93|url=http://pediatrics.aappublications.org/cgi/pmidlookup?view=long&pmid=9917445}}</ref><ref name="pmid17972535">{{cite journal |author=Kokavec M, Bialik V |title=Developmental dysplasia of the hip. Prevention and real incidence |journal=[[Bratisl Lek Listy]] |volume=108 |issue=6 |pages=251–4 |year=2007 |pmid=17972535 |doi=}}</ref> In addition there is a wide margin in diagnostic results. A German study comparing two methods resulted in twice the usual rate for one method.


In order to do the Ortolani maneuver it is recommended that the examiner put the newborn baby in a position in which the opposite hip is held still while the thigh of the hip being tested is abducted and gently pulled anteriorly. If a "clunk" is heard (the sound of the femoral head moving over the acetabulum), the joint is normal, but absence of the "clunk" sound indicates that the acetabulum is not fully developed. The next method that can be used is called the Barlow maneuver. It is done by adducting the hip while pushing the thigh posteriorly. If the hip goes out of the socket it means it is dislocated, and the newborn has a congenital hip dislocation. The baby is laid on its back for examination by separation of its legs. If a clicking sound can be heard, it indicates that the baby may have a dislocated hip. It is highly recommended that these maneuvers be done when the baby is not fussing, because the baby may inhibit hip movement.{{citation needed|date=June 2022}}. Overall, the latest evidence suggests that clinical screening tests are not sufficiently reliable for diagnosing [[hip dysplasia (human)|developmental dysplasia of the hip]].<ref>{{cite journal |last1=Singh |first1=Abhinav |last2=Wade |first2=Ryckie George |last3=Metcalfe |first3=David |last4=Perry |first4=Daniel C. |title=Does This Infant Have a Dislocated Hip?: The Rational Clinical Examination Systematic Review |journal=JAMA |date=14 May 2024 |volume=331 |issue=18 |pages=1576 |doi=10.1001/jama.2024.2404}}</ref>
An instability rate of 1:60 has been described, though this rate drops to 1:240 at one week.<ref name="urlUNSW Embryology- Musculoskeletal System - Abnormalities">{{cite web |url=http://embryology.med.unsw.edu.au/Notes/skmus2.htm |title=UNSW Embryology- Musculoskeletal System - Abnormalities |work=}}</ref> The condition is eight times more frequent in females than in males.<ref name=autogenerated2>[http://aappolicy.aappublications.org/cgi/content/full/pediatrics;105/4/896 Clinical Practice Guideline: Early Detection of Developmental Dysplasia of the Hip - Committee on Quality Improvement, Subcommittee on Developmental Dysplasia of the Hip 105 (4): 896 - AAP Policy<!-- Bot generated title -->]</ref>


There is some evidence suggesting that hip examinations in newborns are painful and pain relief in the form of oral glucose has been suggested but is not yet widely accepted.<ref>{{Cite journal |last1=Olsson |first1=Emma |last2=Pettersson |first2=Miriam |last3=Eriksson |first3=Mats |last4=Ohlin |first4=Andreas |date=April 2019 |title=Oral sweet solution to prevent pain during neonatal hip examination: a randomised controlled trial |journal=Acta Paediatrica |language=en |volume=108 |issue=4 |pages=626–629 |doi=10.1111/apa.14588 |pmc=6585692 |pmid=30246505}}</ref><ref>{{Cite journal |last1=Pettersson |first1=Miriam |last2=Olsson |first2=Emma |last3=Ohlin |first3=Andreas |last4=Eriksson |first4=Mats |date=September 2019 |title=Neurophysiological and behavioral measures of pain during neonatal hip examination |journal=Paediatric and Neonatal Pain |language=en |volume=1 |issue=1 |pages=15–20 |doi=10.1002/pne2.12006 |issn=2637-3807 |pmc=8974883 |pmid=35546870}}</ref>
==Causes==


Most vexingly, many newborn hips show a certain [[ligamentous laxity]], on the other hand severely malformed joints can appear stable. That is one reason why follow-up exams and developmental monitoring are important. Physical examination of newborns followed by appropriate use of hip ultrasound is widely accepted.<ref name="Physician Newborn Screening and Prevention">{{cite web|title=Physician Newborn Screening and Prevention - International Hip Dysplasia Institute|url=http://www.hipdysplasia.org/for-physicians/pediatricians-and-primary-care-providers/newborn-screening-and-prevention/|access-date=31 August 2012|archive-date=12 November 2020|archive-url=https://web.archive.org/web/20201112041651/https://hipdysplasia.org/for-physicians/pediatricians-and-primary-care-providers/newborn-screening-and-prevention/|url-status=dead}}</ref>
{{cleanup|section|date=November 2008}}


The Harris hip score<ref>{{cite web|url=http://www.orthopaedicscore.com/scorepages/harris_hip_score.html|title=Harris Hip Score - Orthopaedic Scores|website=www.orthopaedicscore.com}}</ref> (developed by William H. Harris MD, an orthopedist from Massachusetts) is one way to evaluate hip function following surgery. Other scoring methods are based on patients' evaluation like e.g. the Oxford hip score, HOOS and [[WOMAC]] score.<ref name="pmid16259627">{{cite journal |vauthors=Wylde V, Learmonth ID, Cavendish VJ |title=The Oxford hip score: the patient's perspective |journal=[[Health Qual Life Outcomes]] |volume=3 |pages=66 |year=2005 |pmid=16259627 |doi=10.1186/1477-7525-3-66 |pmc=1283979 |doi-access=free }}</ref> Children's Hospital Oakland Hip Evaluation Scale (CHOHES) is a modification of the Harris hip score that is currently being evaluated.<ref name="pmid16003666">{{cite journal |vauthors=Aguilar CM, Neumayr LD, Eggleston BE, etal |title=Clinical evaluation of avascular necrosis in patients with sickle cell disease: Children's Hospital Oakland Hip Evaluation Scale--a modification of the Harris Hip Score |journal=[[Arch Phys Med Rehabil]] |volume=86 |issue=7 |pages=1369–75 |year=2005 |pmid=16003666 |doi= 10.1016/j.apmr.2005.01.008}}</ref>
Hip dysplasia is considered to be a [[multifactorial inheritance|multifactorial]] condition. That means that several factors are involved in causing the condition to manifest.<ref>Lynn T Staheli, Fundamentals of Pediatric Orthopedics, p 13</ref> Cause is unknown but common in breech position or large fetal size.


Hip dysplasia can develop in older age. Adolescents and adults with hip dysplasia may present with a waddling gait, Trendelenburg's sign, decreased hip abduction, hip pain and in some cases hip labral tears. X-rays are used to confirm a diagnosis of hip dysplasia. CT scans and MRI scans are occasionally used too.<ref>Betsy Miller, The Parents' Guide to Hip Dysplasia, p 19.</ref><ref>{{cite book |last1=Sutherland |first1=Denise |last2=West |first2=Sophie |title=A Guide for Adults with Hip Dysplasia |url=http://sutherland-studios.com.au/books/hip-dysplasia.php |year=2011 |isbn=978-0-9872152-0-8 |pages=7, 21–23 |publisher=Lulu.com |access-date=2 April 2013 |archive-url=https://web.archive.org/web/20130410044432/http://sutherland-studios.com.au/books/hip-dysplasia.php |archive-date=10 April 2013 |url-status=dead }}</ref>
===Congenital===


===Terminology===
Some studies suggest a hormonal link.<ref name=autogenerated2 /> Specifically the hormone [[relaxin]] has been indicated.<ref name="pmid9128773">{{cite journal |author=Forst J, Forst C, Forst R, Heller KD |title=Pathogenetic relevance of the pregnancy hormone relaxin to inborn hip instability |journal=Arch Orthop Trauma Surg |volume=116 |issue=4 |pages=209–12 |year=1997 |pmid=9128773 |doi= 10.1007/BF00393711|url=}}</ref>
Some sources prefer "developmental dysplasia of the hip" (DDH) to "congenital dislocation of the hip" (CDH), finding the latter term insufficiently flexible in describing the diversity of potential complications.<ref name="urlDevelopmental Dysplasia of the Hip - October 15, 2006 -- American Family Physician">{{cite journal |url=http://www.aafp.org/afp/20061015/1310.html |title=Developmental Dysplasia of the Hip |journal=American Family Physician |volume=74 |issue=8 |pages=1310–1316 |date=15 October 2006 |last1=Skaggs |first1=David L. |last2=Storer |first2=Stephen K. |pmid=17087424 |access-date=19 April 2008 |archive-date=16 October 2008 |archive-url=https://web.archive.org/web/20081016080115/http://www.aafp.org/afp/20061015/1310.html |url-status=dead }}</ref>


The use of the word congenital can also imply that the condition already exists at birth. This terminology introduces challenges, because the joint in a newborn is formed from [[cartilage]] and is still [[malleable]], making the onset difficult to ascertain. The newer term DDH also encompasses [[occult]] dysplasia (e.g. an underdeveloped [[joint]]) without [[Joint dislocation|dislocation]] and a dislocation developing after the "[[Infant|newborn]]" phase.{{citation needed|date=October 2020}}
A genetic factor is indicated by the trait running in families and increased occurrence in some ethnic populations (e.g. [[Native Americans in the United States|native Americans]],<ref>[http://fds.oup.com/www.oup.co.uk/pdf/0-19-263161-6.pdf CHSC01<!-- Bot generated title -->]</ref> Lapps<ref>[http://www3.interscience.wiley.com/cgi-bin/abstract/110503598 The occurrence of hip joint dislocation in early Lappic populations of Norway],
Per Holck, Anthropological Department, Anatomical Institute, Box 1105 Blindern, N-0317 Oslo 3, Norway</ref> / [[Sami people]]<ref name="pmid11077514">{{cite journal |author=Forsdahl A |title=[A physician from Finnmark who pointed out the significance of heredity in congenital hip dysplasia] |language=Norwegian |journal=[[Tidsskr. Nor. Laegeforen.]] |volume=120 |issue=22 |pages=2672–3 |year=2000 |pmid=11077514 |doi=}}</ref>). A locus has been described on [[chromosome 13]].<ref name="pmid16773577">{{cite journal |author=Mabuchi A, Nakamura S, Takatori Y, Ikegawa S |title=Familial osteoarthritis of the hip joint associated with acetabular dysplasia maps to chromosome 13q |journal=[[Am. J. Hum. Genet.]] |volume=79 |issue=1 |pages=163–8 |year=2006 |pmid=16773577 |doi=10.1086/505088 |url=http://linkinghub.elsevier.com/retrieve/pii/S0002-9297(07)60018-4 |pmc=1474113}}</ref> Beukes familial dysplasia, on the other hand, was found to [[Genetic mapping|map]] to an 11-cM region on chromosome 4q35. With [[Penetrance|nonpenetrant]] carriers not affected.<ref>[http://www.ajhg.org/AJHG/fulltext/S0002-9297(07)61731-5 AJHG - Autosomal Dominant (Beukes) Premature Degenerative Osteoarthropathy of the Hip Joint Maps to an 11-cM Region on Chromosome 4q35<!-- Bot generated title -->]</ref>


The term is not used consistently. In pediatric/neonatal orthopedics it is used to describe unstable/dislocatable hips and poorly developed acetabula. For adults it describes hips showing abnormal femur head or acetabular x-rays.<ref>{{cite web|url=http://faculty.washington.edu/momus/PB/ddh.htm|title=Dr. Rose's Peripheral Brain--DEVELOPMENTAL DYSPLASIA OF THE HIP|website=faculty.washington.edu|access-date=22 April 2008|archive-date=10 June 2017|archive-url=https://web.archive.org/web/20170610204237/http://faculty.washington.edu/momus/PB/ddh.htm|url-status=dead}}</ref><ref name=autogenerated1>{{cite journal|url=http://www.aafp.org/afp/990700ap/177.html|title=Screening for Developmental Dysplasia of the Hip|first1=Frederick R.|last1=Dietz|first2=Linda|last2=Speer|date=1 July 1999|journal=American Family Physician|volume=60|issue=1|pages=177–84, 187–8|pmid=10414637|access-date=14 April 2008|archive-date=6 July 2008|archive-url=https://web.archive.org/web/20080706181837/http://www.aafp.org/afp/990700ap/177.html|url-status=dead}}</ref>
===Acquired===
As an acquired condition it has often been linked to traditions of [[swaddling]] infants<ref name="pmid18166571">{{cite journal |author=Mahan ST, Kasser JR |title=Does swaddling influence developmental dysplasia of the hip? |journal=[[Pediatrics (journal)|Pediatrics]] |volume=121 |issue=1 |pages=177–8 |year=2008 |pmid=18166571 |doi=10.1542/peds.2007-1618 |url=http://pediatrics.aappublications.org/cgi/pmidlookup?view=long&pmid=18166571}}</ref> or use of a [[cradle board]] which locks the hip joint in an "adducted" position (pulling the knees together tends to pull the heads of the femur bone out of the sockets or acetabulae) for extended periods. Modern swaddling techniques allow some room for leg movement.<ref name="urlThe Right Way to Swaddle - Well - Tara Parker-Pope - Health - New York Times Blog">{{cite news |url=http://well.blogs.nytimes.com/2008/01/14/the-right-way-to-swaddle/ |title=The Right Way to Swaddle - Well - Tara Parker-Pope - Health - New York Times Blog |format= |work=The New York Times | date=January 14, 2008 | accessdate=May 4, 2010}}</ref>


Some sources prefer the term "hip dysplasia" over DDH, considering it to be "simpler and more accurate", partly because of the redundancy created by the use of the terms [[developmental]] and [[dysplasia]].<ref name="urleMedicine - Developmental Dysplasia of the Hip: Article by James McCarthy, MD, FAAOS">{{cite journal |url=http://www.emedicine.com/orthoped/topic456.htm |title=eMedicine - Developmental Dysplasia of the Hip : Article by James McCarthy, MD, FAAOS |date=20 October 2019 }}</ref> Types of DDH include subluxation, dysplasia, and dislocation. The main types are the result of either laxity of the supporting capsule or an abnormal acetabulum.
Further risk factors include [[breech birth]] and firstborns.<ref name="urlDevelopmental Dislocation of the Hip - Wheeless Textbook of Orthopaedics">{{cite web |url=http://www.wheelessonline.com/ortho/developmental_dislocation_of_the_hip |title=Developmental Dislocation of the Hip - Wheeless' Textbook of Orthopaedics |format= |work=}}</ref> In breech position the femoral head tends to get pushed out of the socket. A narrow uterus also facilitates hip joint dislocation during fetal development and birth.


==Diagnostics==
===Imaging===
{{See also|X-ray of hip dysplasia}}
Most countries have standard newborn exams that include a hip joint exam [[Screening (medicine)|screening]] for early detection of hip dysplasia.
It can often be detected by a "click" or more precisely "clunk" in the hip<ref name="urlHipDysplasia - Newborn Nursery at LPCH - Stanford University School of Medicine">{{cite web |url=http://newborns.stanford.edu/HipDysplasia.html |title=HipDysplasia - Newborn Nursery at LPCH - Stanford University School of Medicine |work=}}</ref> (although not all clicks indicate hip dysplasia).<ref name="pmid15977515">{{cite journal |author=Kamath S, Bramley D |title=Is 'clicky hip' a risk factor in developmental dysplasia of the hip? |journal=[[Scott Med J]] |volume=50 |issue=2 |pages=56–8 |year=2005 |pmid=15977515 |doi=}}</ref>
Two maneuvers commonly employed for diagnosis in neonatal exams are the [[Ortolani maneuver]] and the [[Barlow maneuver]].


Hip dysplasia can be diagnosed by [[ultrasound]]<ref name="Ultrasound detection of DDH">{{cite web|title=Ultrasound Detection of DDH - International Hip Dysplasia Institute|url=http://www.hipdysplasia.org/developmental-dysplasia-of-the-hip/infant-diagnosis/ultrasound/|access-date=31 August 2012|archive-date=4 December 2020|archive-url=https://web.archive.org/web/20201204021043/https://hipdysplasia.org/developmental-dysplasia-of-the-hip/infant-diagnosis/ultrasound/|url-status=dead}}</ref> and [[projectional radiography]] ("X-ray").<ref name="X-Ray Screening">{{cite web|title=X-Ray Screening for Developmental Dysplasia of the Hip - International Hip Dysplasia Institute|url=http://www.hipdysplasia.org/developmental-dysplasia-of-the-hip/infant-diagnosis/x-ray-screening/|access-date=31 August 2012|archive-date=4 December 2020|archive-url=https://web.archive.org/web/20201204020355/https://hipdysplasia.org/developmental-dysplasia-of-the-hip/infant-diagnosis/x-ray-screening/|url-status=dead}}</ref> Ultrasound imaging is generally preferred at up to 4 months due to limited [[ossification]] of the femoral head up until then, and is the most accurate method for imaging of the hip during the first few months after birth. However, in most instances, ultrasound screening should not be performed before 3 to 4 weeks of age because of the normal physiologic laxity.<ref name=acr/><ref group="notes" name=surveillance/> When universal with targeted ultrasound screening was compared, the former results in an insignificant reduction in the late diagnosis of hip dysplasia, which is why universal ultrasonographic screening of newborn infants is not recommended by the American Academy of Pediatrics.<ref name=aap>{{Cite journal |last1=Shaw |first1=Brian A. |last2=Segal |first2=Lee S. |last3=SECTION ON ORTHOPAEDICS |last4=Otsuka |first4=Norman Y. |last5=Schwend |first5=Richard M. |last6=Ganley |first6=Theodore John |last7=Herman |first7=Martin Joseph |last8=Hyman |first8=Joshua E. |last9=Shaw |first9=Brian A. |last10=Smith |first10=Brian G. |display-authors=3 |date=2016-12-01 |title=Evaluation and Referral for Developmental Dysplasia of the Hip in Infants |url=https://publications.aap.org/pediatrics/article/138/6/e20163107/52541/Evaluation-and-Referral-for-Developmental |journal=Pediatrics |language=en |volume=138 |issue=6 |pages=e20163107 |doi=10.1542/peds.2016-3107 |pmid=27940740 |s2cid=32575088 |issn=0031-4005|doi-access=free }}</ref>
The condition can be confirmed by [[ultrasound]] and [[X-ray]]. Ultrasound imaging yields better results defining the anatomy until the cartilage is [[ossified]]. When the infant is around 3 months old a clear roentgenographic image can be achieved. Unfortunately the time the joint gives a good x-ray image is also the point at which nonsurgical treatment methods cease to give good results. In x-ray imaging dislocation may be indicated if the Shenton's line (an arc drawn from the medial aspect of the [[femoral neck]] through the superior margin of the [[obturator foramen]]<ref name="urlShentons line (www.whonamedit.com)">{{cite web |url=http://www.whonamedit.com/synd.cfm/2456.html |title=Shenton's line (www.whonamedit.com) |work=}}</ref>) does not result in a smooth arc. However in infants this line can be unreliable as it depends on the rotation of the hip when the image is taken (<ref>{{cite web | url=http://www.wheelessonline.com/ortho/radiographic_features_ddh |title=Radiographic features: DDH | Format= | work=Weeless' Textbook of Orthopaedics}}</ref>)


Despite the widespread use of ultrasound, pelvis X-ray is still frequently used to diagnose or monitor hip dysplasia or for assessing other congenital conditions or bone tumors.<ref name="Ruiz SantiagoSantiago Chinchilla2016">Initially largely copied from: {{cite journal|last1=Ruiz Santiago|first1=Fernando|last2=Santiago Chinchilla|first2=Alicia|last3=Ansari|first3=Afshin|last4=Guzmán Álvarez|first4=Luis|last5=Castellano García|first5=Maria del Mar|last6=Martínez Martínez|first6=Alberto|last7=Tercedor Sánchez|first7=Juan|title=Imaging of Hip Pain: From Radiography to Cross-Sectional Imaging Techniques|journal=Radiology Research and Practice|volume=2016|year=2016|pages=1–15|issn=2090-1941|doi=10.1155/2016/6369237|pmid=26885391|pmc=4738697|doi-access=free}} [https://creativecommons.org/licenses/by/4.0/ Attribution 4.0 International (CC BY 4.0)] license</ref>
<gallery>
Image:Pelvis calculations.jpg|X-Ray showing calculations for working out hip dysplasia
Image:Dislocated hip.jpg|X-Ray Image showing Hip Dysplasia in an Infant
</gallery>


{|class="wikitable" align="left"
Asymmetrical [[gluteal fold]]s and an apparent limb-length inequality can further indicate unilateral hip dysplasia. Most vexingly, many newborn hips show a certain [[ligamentous laxity]], on the other hand severely malformed joints can appear stable. That is one reason why follow-up exams and developmental monitoring are important. Routine ultrasound screening has been discussed and rejected mainly because the small benefit would not justify the costs.<ref>http://www.york.ac.uk/inst/crd/projects/hipdysplasia.htm</ref>
|+ [[ACR Appropriateness Criteria|American College of Radiology Appropriateness Criteria]] for hip dysplasia<ref name=acr>{{cite web|url=https://acsearch.acr.org/docs/69437/Narrative/|title=ACR Appropriateness Criteria - Developmental Dysplasia of the Hip (DDH)–Child|website=[[American College of Radiology]]}} Revised 2018</ref>
! Age !! Scenario !! Usual appropriate initial imaging
|-
!rowspan=2| <4 weeks
| Equivocal physical examination or risk factors || No imaging
|-
| Physical findings of DDH || Ultrasonography
|-
! 4 weeks - 4 months
| Equivocal physical examination or risk factors || Ultrasonography
|-
! 4 – 6 months
| Concern for DDH || X-ray. Ultrasonography may be appropriate<ref group="notes" name="surveillance">Ultrasonography is the imaging method of choice up to 6 months for the nonoperative surveillance imaging in harness of known diagnosis of DDH.<br>- {{cite web|url=https://acsearch.acr.org/docs/69437/Narrative/|title=ACR Appropriateness Criteria - Developmental Dysplasia of the Hip (DDH)–Child|website=[[American College of Radiology]]}} Revised 2018</ref>
|-
! >6 months
| || X-ray
|}


The most useful lines and angles that can be drawn in the pediatric pelvis assessing hip dysplasia are as follows:<ref name="Ruiz SantiagoSantiago Chinchilla2016"/> Different measurements are used in adults.<ref name="Ruiz SantiagoSantiago Chinchilla2016"/>
The Harris hip score<ref>[http://www.orthopaedicscore.com/scorepages/harris_hip_score.html Harris Hip Score - Orthopaedic Scores<!-- Bot generated title -->]</ref> (developed by William H. Harris MD, an orthopedist from Massachusetts) is one way to evaluate hip function following surgery. Other scoring methods are based on patients' evaluation like e.g. the Oxford hip score, HOOS and [[WOMAC]] score.<ref name="pmid16259627">{{cite journal |author=Wylde V, Learmonth ID, Cavendish VJ |title=The Oxford hip score: the patient's perspective |journal=[[Health Qual Life Outcomes]] |volume=3 |issue= |pages=66 |year=2005 |pmid=16259627 |doi=10.1186/1477-7525-3-66 |url=http://www.hqlo.com/content/3//66 |pmc=1283979}}</ref> Children's Hospital Oakland Hip Evaluation Scale (CHOHES) is a modification of the Harris hip score that is currently being evaluated.<ref name="pmid16003666">{{cite journal |author=Aguilar CM, Neumayr LD, Eggleston BE, ''et al.'' |title=Clinical evaluation of avascular necrosis in patients with sickle cell disease: Children's Hospital Oakland Hip Evaluation Scale--a modification of the Harris Hip Score |journal=[[Arch Phys Med Rehabil]] |volume=86 |issue=7 |pages=1369–75 |year=2005 |pmid=16003666 |doi= 10.1016/j.apmr.2005.01.008|url=http://linkinghub.elsevier.com/retrieve/pii/S0003999305002145}}</ref>
<gallery mode="packed" heights="250">
File:X-ray of measurements on a normal hip.jpg|Normal hip.<ref name="Ruiz SantiagoSantiago Chinchilla2016"/>
File:X-ray of measurements in hip dysplasia.jpg|Hip dysplasia.<ref name="Ruiz SantiagoSantiago Chinchilla2016"/>
</gallery>


==Treatment==
==Treatment==
Hip dysplasia presents a nearly perfect equilibrium between the arthritis, movement/mobility problems and pain associated with the developmental malformation, and the arthritis, movement/mobility problems and pain that are, as often as not in moderate to severe cases, inflicted by the treatment itself.{{citation needed|date=October 2020}}
Given the very real possibility of a limp, constant and/or debilitating pain, complicated treatment and impaired mobility later in life, careful developmental monitoring and early intervention are indicated. The worst possible consequence of non treatment is developing early arthritis, sometimes even during teenage years. All treatment aims to delay the onset of arthritis, but no treatment is fully successful in avoiding it.

However, given the very real possibility of a limp, constant and/or debilitating pain, complicated treatment and impaired mobility later in life, careful developmental monitoring is indicated and early intervention is often the best result. The worst possible consequence of non treatment is developing early arthritis, sometimes even during teenage years. All treatment aims to delay the onset of arthritis, but no treatment is fully successful in avoiding it; and, all available treatments bear the risk of inflicting equivalent damage. Most unfortunately, studies have as yet been unable to find a method of predicting outcomes in either the surgical/orthopedic treatment of the condition in infants and young children, or the surgical treatment of these early treatments' negative outcomes later in life (such as arthritis, avascular necrosis, trochanteric bursitis, and [[bone spur]]s of up to 3.5&nbsp;cm just medial of the gluteus maximus insertion point on the greater trochanter due to excessive friction).{{citation needed|date=October 2020}}


===Harnesses, casts, and traction===
===Harnesses, casts, and traction===
Early hip dysplasia can often be treated using a Pavlik harness (see photograph) or the Frejka pillow/splint<ref name="pmid17676003">{{cite journal |author=Czubak J, Piontek T, Niciejewski K, Magnowski P, Majek M, Płończak M |title=Retrospective analysis of the non-surgical treatment of developmental dysplasia of the hip using Pavlik harness and Fredjka pillow: comparison of both methods |journal=[[Ortop Traumatol Rehabil]] |volume=6 |issue=1 |pages=9–13 |year=2004 |pmid=17676003 |doi=}}</ref> in the first year of life with usually normal results. Cases of femoral head avascular necrosis have been reported with the use of the Pavlik harness,<ref name="pmid17322441">{{cite journal |author=Nakamura J, Kamegaya M, Saisu T, Someya M, Koizumi W, Moriya H |title=Treatment for developmental dysplasia of the hip using the Pavlik harness: long-term results |journal=[[J Bone Joint Surg Br]] |volume=89 |issue=2 |pages=230–5 |year=2007 |pmid=17322441 |doi=10.1302/0301-620X.89B2.18057 |url=http://www.jbjs.org.uk/cgi/pmidlookup?view=long&pmid=17322441}}</ref> but whether these cases were due to improper application of the device or a complication encountered in the course of the disorder remains unresolved. Complications arise mainly because the sheet of the iliopsoas muscle pushes circumflex artery against the neck of the femur and decreases blood flow to the femoral head. That is the reason why the Frejka pillow is not indicated in all the forms of the developmental dysplasia of the hip.{{Citation needed|date=January 2009}}
Early hip dysplasia can often be treated using a Pavlik harness<ref name="Pavlik Harness for Hip Dysplasia">{{cite web |title=Pavlik Harness |url=http://www.hipdysplasia.org/developmental-dysplasia-of-the-hip/child-treatment-methods/pavlik-harness/ |access-date=31 August 2012 |archive-date=22 October 2020 |archive-url=https://web.archive.org/web/20201022235730/https://hipdysplasia.org/developmental-dysplasia-of-the-hip/child-treatment-methods/pavlik-harness/ |url-status=dead }}</ref> (see photograph) or the Frejka pillow/splint<ref name="pmid17676003">{{cite journal |vauthors=Czubak J, Piontek T, Niciejewski K, Magnowski P, Majek M, Płończak M |title=Retrospective analysis of the non-surgical treatment of developmental dysplasia of the hip using Pavlik harness and Fredjka pillow: comparison of both methods |journal=[[Ortop Traumatol Rehabil]] |volume=6 |issue=1 |pages=9–13 |year=2004 |pmid=17676003 }}</ref> in the first year of life with usually normal results. Complications can occur when using the Pavlik harness. Cases of [[femoral nerve]] palsy<ref name="Femoral Nerve Palsy and the Pavlik Harness">{{cite journal|title=Femoral Nerve Palsy|journal=The Journal of Arthroplasty |date=April 2018 |volume=33 |issue=4 |pages=1194–1199 |doi=10.1016/j.arth.2017.10.050 |pmid=29239773 |url=https://pubmed.ncbi.nlm.nih.gov/29239773/|last1=Fleischman |first1=Andrew N. |last2=Rothman |first2=Richard H. |last3=Parvizi |first3=Javad }}</ref> and [[avascular necrosis]] of the femoral head have been reported with the use of the Pavlik harness,<ref name="pmid17322441">{{cite journal |vauthors=Nakamura J, Kamegaya M, Saisu T, Someya M, Koizumi W, Moriya H |title=Treatment for developmental dysplasia of the hip using the Pavlik harness: long-term results |journal=[[J Bone Joint Surg Br]] |volume=89 |issue=2 |pages=230–5 |year=2007 |pmid=17322441 |doi=10.1302/0301-620X.89B2.18057 |url=http://www.jbjs.org.uk/cgi/pmidlookup?view=long&pmid=17322441 |archive-url=https://archive.today/20121224044909/http://www.jbjs.org.uk/cgi/pmidlookup?view=long&pmid=17322441 |url-status=dead |archive-date=24 December 2012 }}</ref> but whether these cases were due to improper application of the device or a complication encountered in the course of the disorder remains unresolved. Complications arise mainly because the sheet of the [[iliopsoas muscle]] pushes the circumflex artery{{specify|date=June 2022}} against the neck of the femur and decreases blood flow to the femoral head, so the Frejka pillow is not indicated in all the forms of the developmental dysplasia of the hip. {{Citation needed|date=January 2009}}


<gallery mode="packed" widths="360px" heights="220">
<gallery>
Image:Saeugling mit angelegter spreizhose.jpg|baby wearing a [http://www.ottobock.com/cps/rde/xchg/ob_com_en/hs.xsl/622.html Bock] harness
File:Saeugling mit angelegter spreizhose.jpg|Baby wearing a Pavlik harness
Image:Pavlik.jpg|Diagram of Pavlik harness
File:Pavlik.jpg|Diagram of Pavlik harness
Image:Frejka.jpg|Diagram of Frejka pillow
File:Frejka.jpg|Diagram of Frejka pillow
Image:Tractie.jpg|Traction
File:Tractie.jpg|Traction
</gallery>
</gallery>


Other devices employed include the [[spica cast]],<ref name="Spica Cast for DDH">{{cite web|title=Hip Spica Cast for Developmental Dysplasia of the Hip|url=http://www.hipdysplasia.org/developmental-dysplasia-of-the-hip/child-treatment-methods/hip-spica-cast/|access-date=31 August 2012|archive-date=4 December 2020|archive-url=https://web.archive.org/web/20201204021520/https://hipdysplasia.org/developmental-dysplasia-of-the-hip/child-treatment-methods/hip-spica-cast/|url-status=dead}}</ref> particularly following surgical [[Closed Reduction with Internal Fixation|closed reduction]], [[Open reduction internal fixation|open reduction]], or [[osteotomy]] in babies and young children. [[Traction (orthopedics)|Traction]] is sometimes used in the weeks leading up to a surgery to help stretch ligaments in the hip joint, although its use is controversial and varies amongst physicians.<ref name="Traction with DDH Treatment">{{cite web|title=Traction with DDH Treatment|url=http://www.hipdysplasia.org/developmental-dysplasia-of-the-hip/child-treatment-methods/traction/|access-date=31 August 2012|archive-date=4 December 2020|archive-url=https://web.archive.org/web/20201204022053/https://hipdysplasia.org/developmental-dysplasia-of-the-hip/child-treatment-methods/traction/|url-status=dead}}</ref>
Other devices employed include the [[spica cast]], particularly following surgical closed reduction. A few weeks in [[Traction (orthopedics)|traction]] can be used as part of a treatment plan.


===Surgery===
===Surgery===
In older children the [[Abduction (kinesiology)|hip abductor]] and [[Hip flexors|iliopsoas muscles]] have to be treated surgically because they adapt to the dislocated joint position ([[contracture]]).
In older children the adductor and [[Hip flexors|iliopsoas muscles]] may have to be treated surgically because they adapt to the dislocated joint position ([[contracture]]).
Braces and splints are often used following either of these methods to continue treatment.
Braces and splints are often used following either of these methods to continue treatment.
Although some children "outgrow" untreated mild hip dysplasia<ref name=autogenerated1 /> and some forms of untreated dysplasia cause little or no impairment of quality of life, studies have as yet been unable to find a method of predicting outcomes. On the other hand, it has often been documented that starting treatment late leads to complications and ends in poor results.
Although some children "outgrow" untreated mild hip dysplasia<ref name=autogenerated1 /> and some forms of untreated dysplasia cause little or no impairment of quality of life, studies have as yet been unable to find a method of predicting outcomes. On the other hand, it has often been documented that starting treatment late leads to complications and ends in poor results.{{citation needed|date=October 2020}}


====Hip replacement and osteotomy====
===Stem cells===
Hip dysplasia is often cited as causing [[osteoarthritis]] of the hip at a comparatively young age. Dislocated load bearing surfaces lead to increased and unusual wear, although there are studies that contradict these findings (see<ref name="pmid8546528">{{cite journal |vauthors=Lau EM, Lin F, Lam D, Silman A, Croft P |title=Hip osteoarthritis and dysplasia in Chinese men |journal=[[Ann. Rheum. Dis.]] |volume=54 |issue=12 |pages=965–9 |year=1995 |pmid=8546528 |doi= 10.1136/ard.54.12.965|pmc=1010061}}</ref><ref name="pmid15140766">{{cite journal |vauthors=Lievense AM, Bierma-Zeinstra SM, Verhagen AP, Verhaar JA, Koes BW |title=Influence of hip dysplasia on the development of osteoarthritis of the hip |journal=[[Ann. Rheum. Dis.]] |volume=63 |issue=6 |pages=621–6 |year=2004 |pmid=15140766 |doi=10.1136/ard.2003.009860 |pmc=1755018}}</ref>). Peri-acetabular osteotomy (PAO) surgery can be used to realign the hip joint in some adolescents and adults. Subsequent treatment with total hip [[arthroplasty]] ([[hip replacement]]) is complicated by a need for revision surgery (replacing the artificial joint) owing to skeletal changes as the body matures, loosening/wear or bone resorption. [[Hip resurfacing]] is another option for correcting hip dysplasia in adults. It is a type of hip replacement that preserves more bone, and may work for younger hip dysplasia patients.<ref>{{cite book |last1=Sutherland |first1=Denise |last2=West |first2=Sophie |title=A Guide for Adults with Hip Dysplasia |url=http://sutherland-studios.com.au/?page_id=26 |year=2011 |isbn=978-0-9872152-0-8 |pages=56–59 |publisher=Lulu.com }}</ref>
One avenue of research is using [[stem cells]]. They are applied in grafting ([[bone grafting]]) or by seeding porous arthroplasty prosthesis with [[autologous]] [[fibroblasts]] or [[chondrocyte]] [[progenitor cells]] to assist in firmly anchoring the artificial material in the bone bed.


[[osteotomy|Osteotomies]] are either used in conjunction with [[arthroplasty]] or by themselves to correct misalignment.{{citation needed|date=December 2017}}
===Hip replacement and osteotomy===
Hip dysplasia is often cited as causing [[osteoarthritis]] of the hip at a comparatively young age. Dislocated load bearing surfaces lead to increased and unusual wear. Although there are studies that contradict these findings. (see <ref name="pmid8546528">{{cite journal |author=Lau EM, Lin F, Lam D, Silman A, Croft P |title=Hip osteoarthritis and dysplasia in Chinese men |journal=[[Ann. Rheum. Dis.]] |volume=54 |issue=12 |pages=965–9 |year=1995 |pmid=8546528 |doi= 10.1136/ard.54.12.965|url=http://ard.bmj.com/cgi/pmidlookup?view=long&pmid=8546528 |pmc=1010061}}</ref><ref name="pmid15140766">{{cite journal |author=Lievense AM, Bierma-Zeinstra SM, Verhagen AP, Verhaar JA, Koes BW |title=Influence of hip dysplasia on the development of osteoarthritis of the hip |journal=[[Ann. Rheum. Dis.]] |volume=63 |issue=6 |pages=621–6 |year=2004 |pmid=15140766 |doi=10.1136/ard.2003.009860 |url=http://ard.bmj.com/cgi/pmidlookup?view=long&pmid=15140766 |pmc=1755018}}</ref>) Subsequent treatment with total hip [[arthroplasty]] ([[hip replacement]]) is complicated by a need for revision surgery (replacing the artificial joint) owing to skeletal changes as the body matures, loosening/wear or bone resorption.


==Epidemiology==
[[osteotomy|Osteotomies]] are either used in conjunction with [[arthroplasty]] or by themselves to correct misalignment.
Determining the incidence can be difficult.<ref name="pmid9917445">{{cite journal |vauthors=Bialik V, Bialik GM, Blazer S, Sujov P, Wiener F, Berant M |title=Developmental dysplasia of the hip: a new approach to incidence |journal=[[Pediatrics (journal)|Pediatrics]] |volume=103 |issue=1 |pages=93–9 |year=1999 |pmid=9917445 |doi= 10.1542/peds.103.1.93|s2cid=1595498 |url=http://pediatrics.aappublications.org/cgi/pmidlookup?view=long&pmid=9917445}}</ref><ref name="pmid17972535">{{cite journal |vauthors=Kokavec M, Bialik V |title=Developmental dysplasia of the hip. Prevention and real incidence |journal=[[Bratisl Lek Listy]] |volume=108 |issue=6 |pages=251–4 |year=2007 |pmid=17972535 }}</ref> In addition there is a wide margin in diagnostic results. A German study comparing two methods resulted in twice the usual rate for one method. The condition is eight times more frequent in females than in males.<ref name="autogenerated2">{{cite web|url=http://aappolicy.aappublications.org/cgi/content/full/pediatrics;105/4/896|archive-url=https://web.archive.org/web/20050129052959/http://aappolicy.aappublications.org/cgi/content/full/pediatrics;105/4/896|url-status=dead|archive-date=29 January 2005|title=Clinical Practice Guideline: Early Detection of Developmental Dysplasia of the Hip -- Committee on Quality Improvement and Subcommittee on Developmental Dysplasia of the Hip 105 (4): 896 -- AAP Policy|date=29 January 2005}}</ref>


[[Indigenous peoples of the Americas|Native Americans]] are more likely to have congenital hip dislocation than any of the other races. The risk for Native Americans is about 25–50 in 1000. The overall frequency of developmental dysplasia of the hip is approximately 1 case per 1000 individuals; however, Barlow believed that the incidence of hip [[instability]] in newborns can be as high as 1 case for every 60 newborns,<ref>{{EMedicine|article|1248135|Developmental Dysplasia of the Hip}}</ref> with the rate dropping to 1:240 at one week.<ref name="urlUNSW Embryology- Musculoskeletal System - Abnormalities">{{cite web |url=http://embryology.med.unsw.edu.au/Notes/skmus2.htm |title=UNSW Embryology- Musculoskeletal System - Abnormalities |access-date=19 April 2008 |archive-url=https://web.archive.org/web/20080409150747/http://embryology.med.unsw.edu.au/notes/skmus2.htm |archive-date=9 April 2008 |url-status=dead }}</ref>
==Cultural references==


==History==
In the television program "[[ER (TV series)|ER]]," [[Kerry Weaver]] uses a crutch owing to congenital hip dysplasia. In season 12, she undergoes a hip replacement to cure her dysplasia when her previously untreated joint worsens.<ref name="urlOut on a Limb">{{cite web |url=http://www.erheadquarters.com/episodes/12/12261.htm |title=Out on a Limb |work=}}</ref>
The Frejka pillow splint is named after {{ill|Bedřich Frejka|cs|Bedřich Frejka (ortoped)}}. The Pavlik harness is named after {{ill|Arnold Pavlík|wd=Q95436630}}. Both were Czech orthopedic surgeons.{{citation needed|date=October 2020}}


==See also==
==Society and culture==
In the television program ''[[ER (TV series)|ER]]'', [[Kerry Weaver]] uses a crutch owing to congenital hip dysplasia. In season 12, she undergoes a hip replacement to cure her dysplasia when her previously untreated joint worsens.<ref name="ER Episode - Out on a Limb">{{cite web |url=https://www.imdb.com/title/tt0568069/plotsummary |title=ER - Out on a Limb (2006) |website=[[IMDb]] |access-date=31 August 2012}}</ref>
*[[Dislocation of hip]]


==References==
==Research==
One avenue of research is using [[stem cells]]. They are applied in grafting ([[bone grafting]]) or by seeding porous arthroplasty prosthesis with [[autologous]] [[fibroblasts]] or [[chondrocyte]] [[progenitor cells]] to assist in firmly anchoring the artificial material in the bone bed.{{citation needed|date=March 2019}}
{{reflist|2}}


==External links==
==Other animals==
{{Main|Hip dysplasia (canine)}}
* [http://hippreservation.org/ Hip Preservation Awareness, information and support for hip dysplasia, hip impingement, and related issues in the young adult (12-adult)]
In dogs, hip dysplasia is an abnormal formation of the hip socket that, in its more severe form, can eventually cause crippling lameness and painful [[arthritis]] of the joints. It is a genetic (polygenic) trait that is affected by environmental factors. It is common in many dog breeds, particularly the larger breeds.{{citation needed|date=October 2020}}
* [http://www.hipdysplasia.org/ International Hip Dysplasia Institute (IHDI)]
* [http://hipdysplasiahelp.com/ Hip Dysplasia Help]
* Online orthopedic textbook [http://www.wheelessonline.com]
* [http://www.childrenscentralcal.org/content.asp?id=1550&parent=1&groupid=G0055 Childrens Hospital Central California - Developmental Dysplasia of the Hip (DDH)]
* United Kingdom Support group for DDH, Clubfoot and other lower limb disorders [http://www.steps-charity.org.uk/links/4-15-developmental_dysplasia_of_the_hip_ddh.php]


Hip dysplasia is one of the most studied veterinary conditions in dogs, and the most common single cause of arthritis of the hips.{{citation needed|date=July 2022}} Cats are also known to have this condition, especially [[Siamese cat|Siamese]].<ref name=Ettinger_1995>{{cite book|author1=Ettinger, Stephen J. |author2=Feldman, Edward C. |title=Textbook of Veterinary Internal Medicine|edition=4th|publisher=W. B. Saunders Company|year=1995|isbn=0-7216-6795-3}}</ref>

==Notes==
{{Reflist|group="notes"}}

==References==
{{Reflist}}

== External links ==
* [http://www.wheelessonline.com Online orthopedic textbook]
{{Medical resources
| DiseasesDB = 3056
| ICD10 = {{ICD10|Q|65||q|65}}
| ICD9 = {{ICD9|754.3}}
| ICDO =
| OMIM = 142700
| MedlinePlus = 000971
| eMedicineSubj = orthoped
| eMedicineTopic = 456
| MeshID = D006618
}}
{{Congenital malformations and deformations of musculoskeletal system}}
{{Congenital malformations and deformations of musculoskeletal system}}
{{Authority control}}


[[Category:Congenital disorders of musculoskeletal system]]
[[Category:Congenital disorders of musculoskeletal system]]
[[Category:Wikipedia medicine articles ready to translate]]

[[de:Hüftdysplasie]]
[[es:Displasia]]
[[fr:Luxation congénitale de la hanche]]
[[it:Displasia dell'anca]]
[[nl:Heupdysplasie]]
[[ru:Дисплазия тазобедренного сустава]]
[[tr:Doğuştan kalça çıkığı]]

Latest revision as of 22:09, 6 January 2025

Hip dysplasia
Other namesDevelopmental dysplasia of the hip (DDH),[1] developmental dislocation of the hip,[1] congenital dysplasia of the hip (CDH)[2]
Congenital dislocation of the left hip in an elderly person. Closed arrow marks the acetabulum, open arrow the femoral head.
SpecialtyPediatrics, orthopedics
SymptomsNone, hip aches, one leg shorter, limping[1]
ComplicationsArthritis[3]
Risk factorsFamily history, swaddling, breech birth[3]
Diagnostic methodPhysical exam, ultrasound[3]
TreatmentBracing, casting, surgery[3]
PrognosisGood (if detected early)[1]
Frequency1 in 1,000 (term babies)[3]

Hip dysplasia is an abnormality of the hip joint where the socket portion does not fully cover the ball portion, resulting in an increased risk for joint dislocation.[1] Hip dysplasia may occur at birth or develop in early life.[1] Regardless, it does not typically produce symptoms in babies less than a year old.[3] Occasionally one leg may be shorter than the other.[1] The left hip is more often affected than the right.[3] Complications without treatment can include arthritis, limping, and low back pain.[3] Females are affected more often than males.[1] Risk factors for hip dysplasia include female sex, family history, certain swaddling practices, and breech presentation whether an infant is delivered vaginally or by cesarean section.[3] If one identical twin is affected, there is a 40% risk the other will also be affected.[3] Screening all babies for the condition by physical examination is recommended.[3] Ultrasonography may also be useful.[3]

Many of those with mild instability resolve without specific treatment.[3] In more significant cases, if detected early, bracing may be all that is required.[3] In cases that are detected later, surgery and casting may be needed.[3] About 7.5% of hip replacements are done to treat problems which have arisen from hip dysplasia.[3]

About 1 in 1,000 babies have hip dysplasia.[3] Hip instability of meaningful importance occurs in one to two percent of babies born at term.[3] Females are affected more often than males.[1] Hip dysplasia was described at least as early as the 300s BC by Hippocrates.[4]

Signs and symptoms

[edit]
Types of misalignments of femur head to socket in hip dysplasia. A: Normal. B: Dysplasia. C: Subluxation. D: Luxation

Hip dysplasia can range from barely detectable to severely malformed or dislocated. The congenital form, teratologic or non-reducible dislocation occurs as part of more complex conditions.[citation needed]

The condition can be bilateral or unilateral:

  • If both hip joints are affected, one speaks of "bilateral" dysplasia. In this case, some diagnostic indicators like asymmetric folds and leg-length inequality do not apply.
  • In unilateral dysplasia only one joint shows deformity, the opposite side may show resulting effects.[5] In the majority of unilateral cases, the left hip has the dysplasia.

If the joint is fully dislocated a false acetabulum often forms (often higher up on the pelvis) opposite the dislocated femoral head position.

In acetabular dysplasia, the acetabulum (socket) is too shallow or deformed. The center-edge angle is measured as described by Wiberg.[6] Two forms of femoral dysplasia are coxa vara, in which the femur head grows at too narrow an angle to the shaft, and coxa valga, in which the angle is too wide.

A rare type, the "Beukes familial hip dysplasia" is found among Afrikaners that are members of the Beukes family. The femur head is flat and irregular. People develop osteoarthritis at an early age.[7]

Causes

[edit]

Hip dysplasia is considered to be a multifactorial condition. That means that several factors are involved in causing the condition to manifest.[8]

The cause of the condition is unknown; however, some factors of congenital hip dislocation are through heredity and racial background. It is also thought that the higher rates in some ethnic groups (such as some Native American groups) is due to the practice of swaddling of infants, which is known to be a potential risk factor for developing dysplasia. It also has a low risk in African Americans and southern Chinese.[citation needed]

Congenital

[edit]

Some studies suggest a hormonal link.[9] Specifically, the hormone relaxin has been indicated.[10]

Female sex, alone without other known risk factors, accounts for 75%.[11] A genetic factor is indicated since the trait runs in families and there is an increased occurrence in some ethnic populations (e.g., Native Americans,[12] Sami people[13][14]). A locus has been described on chromosome 13.[15] Beukes familial dysplasia, on the other hand, was found to map to an 11-cM region on chromosome 4q35, with nonpenetrant carriers not affected.[16] Further risk factors include, gender, genetics (family history),[17][18] and firstborns.[19]

Acquired

[edit]

In the breech position the femoral head tends to get pushed out of the socket and the breech position is probably the most important single risk factor, whether an infant is delivered vaginally or by cesarean section.[3]

As an acquired condition it has been linked to traditions of swaddling infants,[20] use of overly restrictive baby seats, carriers and other methods of transporting babies,[21] or use of a cradle board which locks the hip joint in an "adducted" position (pulling the knees together tends to pull the heads of the femur bone out of the sockets or acetabulae) for extended periods. Modern swaddling techniques, such as the 'hip healthy swaddle' have been developed to relieve stress on hip joints caused by traditional swaddling methods.[22]

A narrow uterus also facilitates hip joint dislocation during fetal development and birth.[citation needed]

Screening and diagnosis

[edit]
α and β angles used in hip ultrasound
Hip ultrasound
X-Ray Image showing hip dysplasia in a baby

All newborns should be screened for congenital hip dysplasia. The screening examination techniques to detect hip dysplasia in newborns include observation for

  • asymmetry of legs and asymmetrical gluteal folds ,[23]
  • limb length discrepancy (evaluated by placing the child in a supine position with the hips and knees flexed [unequal knee heights might be noticed – the Galeazzi sign]), and
  • restricted hip abduction.

Sometimes during an exam a "click" or more precisely "clunk" in the hip may be detected[24] (although not all clicks indicate hip dysplasia).[25] When a hip click (also known as "clicky hips" in the UK) is detected, the child's hips are tracked with additional screenings[26] to determine if developmental dysplasia of the hip is caused.[27] However, new UK guidelines published in April 2021 have stated that isolated clicks are no longer considered clinically significant and therefore do not meet the screen positive criteria.[28]

Two maneuvers commonly employed for diagnosis in neonatal exams are the Ortolani maneuver and the Barlow maneuver.[29][30]

In order to do the Ortolani maneuver it is recommended that the examiner put the newborn baby in a position in which the opposite hip is held still while the thigh of the hip being tested is abducted and gently pulled anteriorly. If a "clunk" is heard (the sound of the femoral head moving over the acetabulum), the joint is normal, but absence of the "clunk" sound indicates that the acetabulum is not fully developed. The next method that can be used is called the Barlow maneuver. It is done by adducting the hip while pushing the thigh posteriorly. If the hip goes out of the socket it means it is dislocated, and the newborn has a congenital hip dislocation. The baby is laid on its back for examination by separation of its legs. If a clicking sound can be heard, it indicates that the baby may have a dislocated hip. It is highly recommended that these maneuvers be done when the baby is not fussing, because the baby may inhibit hip movement.[citation needed]. Overall, the latest evidence suggests that clinical screening tests are not sufficiently reliable for diagnosing developmental dysplasia of the hip.[31]

There is some evidence suggesting that hip examinations in newborns are painful and pain relief in the form of oral glucose has been suggested but is not yet widely accepted.[32][33]

Most vexingly, many newborn hips show a certain ligamentous laxity, on the other hand severely malformed joints can appear stable. That is one reason why follow-up exams and developmental monitoring are important. Physical examination of newborns followed by appropriate use of hip ultrasound is widely accepted.[34]

The Harris hip score[35] (developed by William H. Harris MD, an orthopedist from Massachusetts) is one way to evaluate hip function following surgery. Other scoring methods are based on patients' evaluation like e.g. the Oxford hip score, HOOS and WOMAC score.[36] Children's Hospital Oakland Hip Evaluation Scale (CHOHES) is a modification of the Harris hip score that is currently being evaluated.[37]

Hip dysplasia can develop in older age. Adolescents and adults with hip dysplasia may present with a waddling gait, Trendelenburg's sign, decreased hip abduction, hip pain and in some cases hip labral tears. X-rays are used to confirm a diagnosis of hip dysplasia. CT scans and MRI scans are occasionally used too.[38][39]

Terminology

[edit]

Some sources prefer "developmental dysplasia of the hip" (DDH) to "congenital dislocation of the hip" (CDH), finding the latter term insufficiently flexible in describing the diversity of potential complications.[40]

The use of the word congenital can also imply that the condition already exists at birth. This terminology introduces challenges, because the joint in a newborn is formed from cartilage and is still malleable, making the onset difficult to ascertain. The newer term DDH also encompasses occult dysplasia (e.g. an underdeveloped joint) without dislocation and a dislocation developing after the "newborn" phase.[citation needed]

The term is not used consistently. In pediatric/neonatal orthopedics it is used to describe unstable/dislocatable hips and poorly developed acetabula. For adults it describes hips showing abnormal femur head or acetabular x-rays.[41][42]

Some sources prefer the term "hip dysplasia" over DDH, considering it to be "simpler and more accurate", partly because of the redundancy created by the use of the terms developmental and dysplasia.[43] Types of DDH include subluxation, dysplasia, and dislocation. The main types are the result of either laxity of the supporting capsule or an abnormal acetabulum.

Imaging

[edit]

Hip dysplasia can be diagnosed by ultrasound[44] and projectional radiography ("X-ray").[45] Ultrasound imaging is generally preferred at up to 4 months due to limited ossification of the femoral head up until then, and is the most accurate method for imaging of the hip during the first few months after birth. However, in most instances, ultrasound screening should not be performed before 3 to 4 weeks of age because of the normal physiologic laxity.[46][notes 1] When universal with targeted ultrasound screening was compared, the former results in an insignificant reduction in the late diagnosis of hip dysplasia, which is why universal ultrasonographic screening of newborn infants is not recommended by the American Academy of Pediatrics.[11]

Despite the widespread use of ultrasound, pelvis X-ray is still frequently used to diagnose or monitor hip dysplasia or for assessing other congenital conditions or bone tumors.[47]

American College of Radiology Appropriateness Criteria for hip dysplasia[46]
Age Scenario Usual appropriate initial imaging
<4 weeks Equivocal physical examination or risk factors No imaging
Physical findings of DDH Ultrasonography
4 weeks - 4 months Equivocal physical examination or risk factors Ultrasonography
4 – 6 months Concern for DDH X-ray. Ultrasonography may be appropriate[notes 1]
>6 months X-ray

The most useful lines and angles that can be drawn in the pediatric pelvis assessing hip dysplasia are as follows:[47] Different measurements are used in adults.[47]

Treatment

[edit]

Hip dysplasia presents a nearly perfect equilibrium between the arthritis, movement/mobility problems and pain associated with the developmental malformation, and the arthritis, movement/mobility problems and pain that are, as often as not in moderate to severe cases, inflicted by the treatment itself.[citation needed]

However, given the very real possibility of a limp, constant and/or debilitating pain, complicated treatment and impaired mobility later in life, careful developmental monitoring is indicated and early intervention is often the best result. The worst possible consequence of non treatment is developing early arthritis, sometimes even during teenage years. All treatment aims to delay the onset of arthritis, but no treatment is fully successful in avoiding it; and, all available treatments bear the risk of inflicting equivalent damage. Most unfortunately, studies have as yet been unable to find a method of predicting outcomes in either the surgical/orthopedic treatment of the condition in infants and young children, or the surgical treatment of these early treatments' negative outcomes later in life (such as arthritis, avascular necrosis, trochanteric bursitis, and bone spurs of up to 3.5 cm just medial of the gluteus maximus insertion point on the greater trochanter due to excessive friction).[citation needed]

Harnesses, casts, and traction

[edit]

Early hip dysplasia can often be treated using a Pavlik harness[48] (see photograph) or the Frejka pillow/splint[49] in the first year of life with usually normal results. Complications can occur when using the Pavlik harness. Cases of femoral nerve palsy[50] and avascular necrosis of the femoral head have been reported with the use of the Pavlik harness,[51] but whether these cases were due to improper application of the device or a complication encountered in the course of the disorder remains unresolved. Complications arise mainly because the sheet of the iliopsoas muscle pushes the circumflex artery[specify] against the neck of the femur and decreases blood flow to the femoral head, so the Frejka pillow is not indicated in all the forms of the developmental dysplasia of the hip. [citation needed]

Other devices employed include the spica cast,[52] particularly following surgical closed reduction, open reduction, or osteotomy in babies and young children. Traction is sometimes used in the weeks leading up to a surgery to help stretch ligaments in the hip joint, although its use is controversial and varies amongst physicians.[53]

Surgery

[edit]

In older children the adductor and iliopsoas muscles may have to be treated surgically because they adapt to the dislocated joint position (contracture). Braces and splints are often used following either of these methods to continue treatment. Although some children "outgrow" untreated mild hip dysplasia[42] and some forms of untreated dysplasia cause little or no impairment of quality of life, studies have as yet been unable to find a method of predicting outcomes. On the other hand, it has often been documented that starting treatment late leads to complications and ends in poor results.[citation needed]

Hip replacement and osteotomy

[edit]

Hip dysplasia is often cited as causing osteoarthritis of the hip at a comparatively young age. Dislocated load bearing surfaces lead to increased and unusual wear, although there are studies that contradict these findings (see[54][55]). Peri-acetabular osteotomy (PAO) surgery can be used to realign the hip joint in some adolescents and adults. Subsequent treatment with total hip arthroplasty (hip replacement) is complicated by a need for revision surgery (replacing the artificial joint) owing to skeletal changes as the body matures, loosening/wear or bone resorption. Hip resurfacing is another option for correcting hip dysplasia in adults. It is a type of hip replacement that preserves more bone, and may work for younger hip dysplasia patients.[56]

Osteotomies are either used in conjunction with arthroplasty or by themselves to correct misalignment.[citation needed]

Epidemiology

[edit]

Determining the incidence can be difficult.[57][58] In addition there is a wide margin in diagnostic results. A German study comparing two methods resulted in twice the usual rate for one method. The condition is eight times more frequent in females than in males.[9]

Native Americans are more likely to have congenital hip dislocation than any of the other races. The risk for Native Americans is about 25–50 in 1000. The overall frequency of developmental dysplasia of the hip is approximately 1 case per 1000 individuals; however, Barlow believed that the incidence of hip instability in newborns can be as high as 1 case for every 60 newborns,[59] with the rate dropping to 1:240 at one week.[60]

History

[edit]

The Frejka pillow splint is named after Bedřich Frejka [cs]. The Pavlik harness is named after Arnold Pavlík [Wikidata]. Both were Czech orthopedic surgeons.[citation needed]

Society and culture

[edit]

In the television program ER, Kerry Weaver uses a crutch owing to congenital hip dysplasia. In season 12, she undergoes a hip replacement to cure her dysplasia when her previously untreated joint worsens.[61]

Research

[edit]

One avenue of research is using stem cells. They are applied in grafting (bone grafting) or by seeding porous arthroplasty prosthesis with autologous fibroblasts or chondrocyte progenitor cells to assist in firmly anchoring the artificial material in the bone bed.[citation needed]

Other animals

[edit]

In dogs, hip dysplasia is an abnormal formation of the hip socket that, in its more severe form, can eventually cause crippling lameness and painful arthritis of the joints. It is a genetic (polygenic) trait that is affected by environmental factors. It is common in many dog breeds, particularly the larger breeds.[citation needed]

Hip dysplasia is one of the most studied veterinary conditions in dogs, and the most common single cause of arthritis of the hips.[citation needed] Cats are also known to have this condition, especially Siamese.[62]

Notes

[edit]
  1. ^ a b Ultrasonography is the imaging method of choice up to 6 months for the nonoperative surveillance imaging in harness of known diagnosis of DDH.
    - "ACR Appropriateness Criteria - Developmental Dysplasia of the Hip (DDH)–Child". American College of Radiology. Revised 2018

References

[edit]
  1. ^ a b c d e f g h i "Your Orthopaedic Connection: Developmental Dysplasia of the Hip". American Academy of Orthopaedic Surgeons. October 2013.
  2. ^ "Definition: congenital dysplasia of the hip from Online Medical Dictionary".[dead link]
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