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Legg-Calvé-Perthes disease

Last updated: October 5, 2021

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Legg-Calvé-Perthes disease (LCPD, or Perthes disease) refers to an idiopathic, avascular necrosis of the femoral head. It may occur unilaterally or bilaterally and typically manifests between the ages of four and ten. Children experience hip pain on weight-bearing, which often projects to the ipsilateral knee and causes an antalgic gait. Early stages are only detectable on MRI but progress of the disease can be tracked and graded using conventional x-ray. Surgery is performed if x-ray reveals signs that indicate an unfavorable prognosis. The aim of surgical intervention is to cover the femoral head as completely as possible with the hip socket, thus retaining its anatomical position. In mild forms of the disease, reduced weight-bearing and physical therapy are indicated. Important prognostic factors include the age of onset and the extent of femoral head involvement.

  • Sex: > (4:1) [1]
  • Age: 4–10 years
  • Incidence (in children < 15 years): 1–3:20,000 [2]

Epidemiological data refers to the US, unless otherwise specified.

  • Idiopathic disease
  • Multiple factors might promote the development and progress of the condition, including: [1]

Lateral pillar classification [6]

This classification possesses the highest clinical relevance because it correlates best with long-term outcome. The crucial criterion in this classification is the height of the lateral third (“lateral pillar”) of the femoral head.

Modified (Herring) Lateral pillar classification
Group A Height of the lateral pillar is 100% (no involvement)
Group B Height of the lateral pillar is > 50%
Group C Height of the lateral pillar is < 50%

Other classifications [7]

  • Catterall classification: refers to the extent of the epiphyseal necrotic area
  • Salter-Thompson classification: refers to the extent of subchondral fracture in the early stage of disease
  • Stulberg classification: refers to femoral head morphology in the phase of complete healing

Avascular necrosis of the femoral head due to a mismatch between the rapid growth of the femoral epiphyses and the slower development of adequate blood supply to the area

Legg-Calvé-Perthes disease should be considered in a child with knee pain.

Differential diagnosis of hip pain in children [11]

Differential diagnosis of pediatric hip pain
Disease Pathophysiology Clinical features Diagnostic findings
Transient synovitis
  • Laboratory: normal
  • Imaging
    • Normal x-ray
    • Effusion on ultrasound that should improve over the course of several days
Septic arthritis
  • Infection either by hematogenous spread of bacteria or direct contamination
  • Any age
  • Acute onset of pain and fever
  • Fever > 38.5°C
  • Child may refuse to bear weight.

Slipped capital femoral epiphysis

  • Laboratory: normal
  • Imaging: X-ray shows displacement of the femoral head.
Legg-Calve-Perthes disease
  • Mismatch between the rapid growth of the femoral epiphyses and the slower development of adequate blood supply to the area
  • 4–10 years of age
  • Insidious onset
  • No fever
  • Vague hip and knee pain (may fluctuate with activity)
  • Can cause the child to limp
  • Laboratory: normal
  • Imaging: x-ray
    • Early stages: often without pathological findings
    • Advanced disease: increased lucency of the femoral head and widened joint spaces
Developmental dysplasia of the hip
  • Laboratory: normal
  • Imaging: Ultrasound before 4 months and x-ray after 4 months are diagnostic.

Pediatric hip pathologies often present as referred pain in the knee! Children or adolescents presenting with nonspecific knee pain and no findings suggestive of knee pathology require prompt assessment of the hip!

Transient synovitis (also known as toxic synovitis) [12]

The differential diagnoses listed here are not exhaustive.

  • Early osteoarthritis of the hip joint due to any of the following: [1]
    • Incongruence between the femoral head and acetabulum
    • Shortening of the femoral neck featuring trochanteric elevation, which can manifest as Trendelenburg sign
    • Lateralization and coxa magna (broadening of the femoral head), which can manifest as hinge abduction

We list the most important complications. The selection is not exhaustive.

  • Factors associated with a less favorable prognosis include: [7][15]
    • Older age of onset (≥ 6 years)
    • Extensive damage to the femoral head (> 50%)
    • Female sex
  1. Mills S, Burroughs KE. Legg Calve Perthes Disease (Calves Disease). StatPearls. 2020 .
  2. Legg-Calvé-Perthes disease. Updated: September 1, 2014. Accessed: October 5, 2020.
  3. Vosmaer A, Pereira RR, Koenderman J, Rosendaal F, Cannegieter S. Coagulation Abnormalities in Legg-Calvé-Perthes Disease. The Journal of Bone and Joint Surgery-American Volume. 2010; 92 (1): p.121-128. doi: 10.2106/jbjs.i.00157 . | Open in Read by QxMD
  4. Eric Gordon J, Schoenecker PL, Osland JD, Dobbs MB, Szymanski DA, Luhmann SJ. Smoking and socio-economic status in the etiology and severity of Legg–Calvé–Perthesʼ disease. Journal of Pediatric Orthopaedics B. 2004; 13 (6): p.367-370. doi: 10.1097/01202412-200411000-00003 . | Open in Read by QxMD
  5. Bahmanyar S, Montgomery SM, Weiss RJ, Ekbom A. Maternal Smoking During Pregnancy, Other Prenatal and Perinatal Factors, and the Risk of Legg-Calve-Perthes Disease. Pediatrics. 2008; 122 (2): p.e459-e464. doi: 10.1542/peds.2008-0307 . | Open in Read by QxMD
  6. Farsetti P, Tudisco C, Caterini R, Potenza V, Ippolito E. The Herring lateral pillar classification for prognosis in Perthes disease. Late results in 49 patients treated conservatively. J Bone Joint Surg Br. 1995; 77-B (5): p.739-742. doi: 10.1302/0301-620x.77b5.7559701 . | Open in Read by QxMD
  7. Rampal V, Clément JL, Solla F. Legg-Calvé-Perthes disease: classifications and prognostic factors.. Clinical cases in mineral and bone metabolism : the official journal of the Italian Society of Osteoporosis, Mineral Metabolism, and Skeletal Diseases. 2017; 14 (1): p.74-82.
  8. Legg Calvé Perthes Disease. Updated: January 1, 2016. Accessed: October 15, 2020.
  9. Skaggs DL, Tolo VT. Legg-Calvé-Perthes Disease. J Am Acad Orthop Surg. 1996; 4 (1): p.9-16. doi: 10.5435/00124635-199601000-00002 . | Open in Read by QxMD
  10. Forster MC, Kumar S, Rajan RA, Guy Atherton W, Asirvatham R, Thava VR. Head-at-risk signs in Legg-Calvé-Perthes disease: Poor inter- and intra-observer reliability. Acta Orthop. 2006; 77 (3): p.413-417. doi: 10.1080/17453670610046334 . | Open in Read by QxMD
  11. Nigrovic PA. Overview of hip pain in childhood. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. updated: May 9, 2016. Accessed: March 8, 2017.
  12. Whitelaw CC, Varacallo M. Transient Synovitis. StatPearls. 2020 .
  13. Leroux J, Abu Amara S, Lechevallier J. Legg-Calvé-Perthes disease. Orthopaedics & Traumatology: Surgery & Research. 2018; 104 (1): p.S107-S112. doi: 10.1016/j.otsr.2017.04.012 . | Open in Read by QxMD
  14. Joseph B. Management of Perthes′ disease. Indian Journal of Orthopaedics. 2015; 49 (1): p.10. doi: 10.4103/0019-5413.143906 . | Open in Read by QxMD
  15. Wiig O, Terjesen T, Svenningsen S. Prognostic factors and outcome of treatment in Perthes’ disease. J Bone Joint Surg Br. 2008; 90-B (10): p.1364-1371. doi: 10.1302/0301-620x.90b10.20649 . | Open in Read by QxMD
  16. Perry DC, Machin DM, Pope D, et al. Racial and geographic factors in the incidence of Legg-Calvé-Perthes' disease: a systematic review.. American Journal of Epidemiology. 2012; 175 (3): p.159-66. doi: 10.1093/aje/kwr293 . | Open in Read by QxMD
  17. Harris GD. Legg-Calve-Perthes Disease. In: Jaffe WL, Legg-Calve-Perthes Disease. New York, NY: WebMD. Updated: May 4, 2015. Accessed: December 22, 2016.
  18. Legg-Calve-Perthes Disease (Coxa plana). Updated: December 22, 2016. Accessed: December 22, 2016.
  19. Perthes disease. Updated: December 22, 2016. Accessed: December 22, 2016.