Legg-Calve-Perthes disease (LCPD) is idiopathic osteonecrosis or idiopathic avascular necrosis of the capital femoral epiphysis of the femoral head. This condition was described independently by Arthur Legg, Jacques Calve, and Georg Perthes in 1910. This process is also known as coxa plana, Legg-Perthes, Legg Calve or Perthes disease. 
The cause of Legg-Calve-Perthes disease is not known. It may be idiopathic or due to other etiology that would disrupt blood flow to the femoral epiphysis such as trauma (macro or repetitive microtrauma), coagulopathy, and steroid use. Thrombophilia is present in approximately 50% of patients and some form of coagulopathy is present in up to 75%.
Legg-Calve-Perthes disease usually occurs between the ages of 3 to 12 years old, with the highest rate of occurrence at 5 to 7 years. It affects 1 in 1200 children under the age of 15. Legg-Calve-Perthes disease occurs most commonly in male patients, with a male to female ratio between 4:1 and 5:1. It is bilateral in 10% to 20% of affected cases. When it occurs bilaterally, it is usually asymmetrical and discovered in different stages of the disease. If it is symmetrical, the examiner must consider multiple epiphyseal dysplasias as the culprit. Caucasians and Asians are more commonly affected. It is also more prevalent in urban areas in patients with lower socioeconomic status. Risk factors for Legg-Calve-Perthes disease include:
Typically, Legg-Calve-Perthes disease includes four phases:
History May Uncover
Physical Examination May Reveal
High Index of Suspicion
Labs are used to exclude other diagnoses (complete blood cell count, ESR within reference range)
Goals of treatment include pain and symptom management, restoration of hip range of motion, and containment of the femoral head in the acetabulum. 
Femoral or Pelvic Osteotomy
Valgus or Shelf Osteotomies
Differential diagnoses that must be considered given the radiographic findings include:
Multiple classifications can be utilized to describe Legg-Calve-Perthes disease. The lateral pillar, or Herring, classification is widely accepted with the best interobserver agreement. It is generally determined at the beginning of the fragmentation stage, approximately 6 months after initial symptom presentation. It cannot be used accurately if the patient has not entered the fragmentation stage radiographically. The goal is to provide prognostic information. This classification is based on the height of the lateral pillar on the AP X-ray image.
Age at Onset
Lateral Pillar Classification (degree of femoral head involvement: A [least] to C [most])
Fifty percent of patients almost fully recover, with no long-term sequelae 
Pain and Disability
Fifty percent of patients develop pain and disability in their 40s and 50s, and degenerative joint disease leading to hip replacement in their 60s and 70s.
Female patients have worse prognoses than male patients if onset occurs at more than 8 years of age.
As Legg-Calve-Perthes disease progresses, various deformities of the femoral head can develop. The most common are coxa magna (widening of the femoral head) and coxa plana (flattening). If the femoral head is damaged, it can result in premature physeal arrest which can lead to leg length discrepancy. A poorly formed femoral head can also lead to acetabular dysplasia and resultant hip incongruency. This can lead to altered mechanics and subsequent labral tears. Lateral hip subluxation or extrusion is a complication associated with a poor outcome and can lead to lifelong problems for the patient. A late complication of this childhood disease is hip arthritis.
LCPD has no cure and the disorder is best managed by an interprofessional team that also includes the orthopedic nurse. LCPD is associated with high morbidity if the diagnosis is missed or delayed. For children with mild disease, non-surgical treatment is recommended with activity restriction and protective weight-bearing until ossification is complete. Clinicians should know that the current literature does not support the use of orthotics, braces or casts. To improve patient outcomes, all cases should be referred to a pediatric orthopedic surgeon as soon as the diagnosis is made. AN orthopedic specialty nurse can help coordinate PT for the patient, along with palliative pharmaceutical care (NSAIDs), and monitor the case for the orthopedist in-between visits. The physical therapist should keep all members of the team informed regarding the progress, or any changes in status, reporting through the nurse to the orthopedist. These are a few examples of interprofessional collaboration that can lead to improved outcomes in these cases. [Level 5]
These patients need long follow up as deformities of the femoral head can develop. Arthritis is not an uncommon complication in childhood.
|||Legg-Calvé-Perthes disease., Leroux J,Abu Amara S,Lechevallier J,, Orthopaedics & traumatology, surgery & research : OTSR, 2018 Feb [PubMed PMID: 29155310]|
|||Vosmaer A,Pereira RR,Koenderman JS,Rosendaal FR,Cannegieter SC, Coagulation abnormalities in Legg-Calvé-Perthes disease. The Journal of bone and joint surgery. American volume. 2010 Jan; [PubMed PMID: 20048104]|
|||Loder RT,Skopelja EN, The epidemiology and demographics of legg-calvé-perthes' disease. ISRN orthopedics. 2011; [PubMed PMID: 24977062]|
|||Dustmann HO, [Etiology and pathogenesis of epiphyseal necrosis in childhood as exemplified with the hip]. Zeitschrift fur Orthopadie und ihre Grenzgebiete. 1996 Sep-Oct; [PubMed PMID: 8967138]|
|||Dobbe AM,Gibbons PJ, Common paediatric conditions of the lower limb. Journal of paediatrics and child health. 2017 Nov; [PubMed PMID: 29148202]|
|||Laine JC,Martin BD,Novotny SA,Kelly DM, Role of Advanced Imaging in the Diagnosis and Management of Active Legg-Calvé-Perthes Disease. The Journal of the American Academy of Orthopaedic Surgeons. 2018 Aug 1; [PubMed PMID: 29939867]|
|||Nguyen NA,Klein G,Dogbey G,McCourt JB,Mehlman CT, Operative versus nonoperative treatments for Legg-Calvé-Perthes disease: a meta-analysis. Journal of pediatric orthopedics. 2012 Oct-Nov; [PubMed PMID: 22955534]|
|||Wiig O,Svenningsen S,Terjesen T, [Legg-Calvé-Perthes disease]. Tidsskrift for den Norske laegeforening : tidsskrift for praktisk medicin, ny raekke. 2011 May 20; [PubMed PMID: 21606991]|
|||Hip preservation surgery for adolescents and young adults with Post-Perthes Sequelae., Eid MA,, Acta orthopaedica Belgica, 2016 Dec [PubMed PMID: 29182124]|
|||Outcomes in patients with late sequelae (healed stage) of Legg-Calvé-Perthes disease undergoing arthroscopic treatment: retrospective case series., Lee WY,Hwang DS,Ha YC,Kim PS,Zheng L,, Hip international : the journal of clinical and experimental research on hip pathology and therapy, 2017 Dec 1 [PubMed PMID: 29192726]|
|||Heesakkers N,van Kempen R,Feith R,Hendriks J,Schreurs W, The long-term prognosis of Legg-Calvé-Perthes disease: a historical prospective study with a median follow-up of forty one years. International orthopaedics. 2015 May; [PubMed PMID: 25408489]|
|||Legg-Calvé-Perthes disease: classifications and prognostic factors., Rampal V,Clément JL,Solla F,, Clinical cases in mineral and bone metabolism : the official journal of the Italian Society of Osteoporosis, Mineral Metabolism, and Skeletal Diseases, 2017 Jan-Apr [PubMed PMID: 28740529]|