Pathophysiology. The course of Perthes disease varies from patient to patient, but does occur in fairly predictable phases. The age at onset is the strongest influential factor on the course of the disease. Basically, the younger the child is at onset, the milder and shorter the course of the disease and the better the outcome.21,25,27 The prognosis worsens significantly with increasing femoral head involvement, particularly if more than half of the head is affected.25,28

The clinical course of Perthes can be broken down into four phases: the synovitis phase, the osteonecrosis phase, the fragmentation phase, and the regeneration phase.

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The synovitis phase lasts a couple of weeks and is typically characterized by reduced range of motion secondary to increased hip joint fluid and thickened synovium. The osteonecrosis phase lasts roughly six to 12 months. This is the period in which the blood supply to the femoral head is interrupted. In this phase the contour of the femoral head is maintained but a portion of the bone becomes ischemic. Next, during the fragmentation phase (which lasts for up to three years), the patient will have pain, limping, and reduced range of motion. The final phase of revascularization and regeneration can last one to three years. During this period, proximal femoral vascularity returns, causing resorption of necrotic bone and development of new immature bone. Permanent hip deformity can occur in this phase.

Diagnosis/physical exam/clinical presentation. Children with Perthes disease will generally present with a limp accompanied by hip pain and/or referred pain to the thigh and possibly the knee (much like SCFE, but typically in a younger child).25 Patients may have decreased range of motion of the hip, particularly rotation and abduction.25 Pain is often exacerbated by physical activity and usually worse by the end of the day. The time course of the pain is characterized by periods of exacerbation and alleviation.

Perthes disease is typically diagnosed with x-rays of the hip, usually performed after the child complains of hip or leg pain or exhibits a limp when walking. Because the x-ray appearance is quite specific for this condition, diagnosis is usually fairly easy.

Treatment. If you ask 10 pediatric orthopedists, you’ll get 10 different recommendations on how to best treat Perthes disease. Initially, treatment focuses on the symptoms. The child may require a period of rest or no weight bearing. Therapeutic goals include minimizing loss of motion.21,25

Bracing or Petrie casting may be employed to contain the femoral head within the acetabulum.21,25 Once the disease has caused the femoral head to lose its spherical shape and flatten, the head may extrude outside the acetabulum. With an abduction brace or Petrie casting, the femoral head can be maintained in its position within the acetabulum.

Healing the effects of Perthes disease does involve revascularization of the femoral head and replacement with new bone, a cycle that can take years to complete.29 Youngsters may be limited in their athletic endeavors and may be unable to participate in physical education classes for quite some time. Those who are nonresponsive to conservative care may undergo a shelf procedure to extend the length of the acetabulum and “cover” the femoral head with bone. If this treatment fails, these patients then become early candidates for hip-replacement surgery.

Conclusion

Without appropriate diagnosis, referral to a pediatric orthopedist, and treatment, these boys and girls with hip disorders may have long-term disabilities. A child’s complaints of pain should always be investigated promptly to ensure that these diagnoses are not missed but rather treated expeditiously and accurately.

Mr. Kleposki is a pediatric orthopedic nurse practitioner and nurse leader, Mrs. Abel is a pediatric orthopedic nurse practitioner, and Ms. Sehgal is a research assistant, all at the Children’s Hospital of Philadelphia. They have no relationships to disclose relating to the content of this article.

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References

  1. New York-Presbyterian/Columbia Orthopaedics. Perthes disease.
  2. American Academy of Orthopaedic Surgeons. Hip implants.
  3. American Academy of Orthopaedic Surgeons. Growth plate fractures.
  4. Wheeless’ Textbook of Orthopaedics. Growth plate anatomy.
  5. Storer SK, Skaggs DL. Developmental dysplasia of the hip. Am Fam Physician. 2006;74:1310-1316.
  6. Quon JA, Burns SH, O’Connor SM, et al. Slipped capital femoral epiphysis: a report of two cases. J Can Chiropr Assoc. 1989;33:130-134.
  7. Keller MS, Nijs ELF. The role of radiographs and US in developmental dysplasia of the hip: how good are they? Pediatr Radiology. 2009;39(Suppl 2):S211-S215.
  8. Bauchner H. Developmental dysplasia of the hip (DDH): an evolving science. Arch Dis Child. 2000;83:202.
  9. Rubini M, Cavallaro A, Calzolari E, et al. Exclusion of COL2A1 and VDR as developmental dysplasia of the hip genes. Clin Orthop Relat Res. 2008;466:878-883.
  10. Staheli LT. Fundamentals of Pediatric Orthopedics. Philadelphia, Pa.: Lippincott Williams & Wilkins; 2008:208-210.
  11. American Academy of Pediatrics Committee on Quality Improvement, Subcommittee on Developmental Dysplasia of the Hip. Clinical practice guideline: early detection of developmental dysplasia of the hip. Pediatrics. 2000;105:896-905.
  12. Shipman SA, Helfand M, Moyer VA, Yawn BP. Screening for developmental dysplasia of the hip: a systematic literature review for the US Preventive Services Task Force. Pediatrics. 2006;117:e557-e576.
  13. Wheeless’ Textbook of Orthopaedics. Barlow’s test.
  14. McCarthy JJ, Scoles PV, MacEwen GD. Developmental dysplasia of the hip (DDH). Curr Orthop. 2005;19:223-230.
  15. Loder RT. The demographics of slipped capital femoral epiphysis: an international multicenter study. Clin Orthop Relat Res. 1996;322:8-27.
  16. Lehmann CL, Arons RR, Loder RT, Vitale MG. The epidemiology of slipped capital femoral epiphysis: an update. J Pediatr Orthop. 2006;26:286-290.
  17. Wells D, King JD, Roe TF, Kaufman FR. Review of slipped capital femoral epiphysis associated with endocrine disease. J Pediatr Orthop. 1993;13:610-614.
  18. Staatz G, Honnef D, Kochs A, et al. Evaluation of femoral head vascularization in slipped capital femoral epiphysis before and after cannulated screw fixation with use of contrast-enhanced MRI: initial results. Eur Radiol. 2007;17:163-168.
  19. Rhoad RC, Davidson RS, Heyman S, et al. Pretreatment bone scan in SCFE: a predictor of ischemia and avascular necrosis. J Pediatr Orthop. 1999;19:164-168.
  20. Harland U, Krappel FA. Value of Ultrasound, CT, and MRI in the diagnosis of slipped capital femoral epiphysis (SCFE). Orthopade. 2002;31:851-856.
  21. Wenger DR, Ward WT, Herring JA. Current concepts review: Legg-Calvé-Perthes disease. J Bone Joint Surg Am. 1991;73:778-788.
  22. Alpaslan AM, Aksoy MC, Yazici M. Interruption of the blood supply of femoral head: an experimental study on the pathogenesis of Legg-Calvé-Perthes disease. Arch Orthop Trauma Surg. 2007;127:485-491.
  23. Szepesi K, Pósán E., Hársfalvi J, et al. The most severe forms of Perthes’ disease associated with the homozygous Factor V Leiden mutation. J Bone Joint Surg Br. 2004;86-B:426-429.
  24. Brenig B, Leeb T, Jansen S, Kopp T. Analysis of blood clotting factor activities in canine Legg-Calvé-Perthes’ disease. J Vet Intern Med. 1999;13:570-573.
  25. Nelitz M, Lippacher S, Krauspe R, Reichel H. Review article: Perthes disease. Dtsch Arztebl Int. 2009;106:517-523.
  26. Balasa VV, Gruppo RA, Glueck CJ, et al. Legg-Calvé-Perthes disease and thrombophilia. J Bone Joint Surg Am. 2004;86A:2642-2647.
  27. Wheeless’ Textbook of Orthopaedics. Legg-Calvé-Perthes disease.
  28. Salter RB, Thompson GH. Legg-Calvé-Perthes disease: the prognostic significance of the subchondral fracture and a two-group classification of the femoral head involvement. J Bone Joint Surg Am. 1984;66:479-489.
  29. Clancy M, Steel HH. The effect of an incomplete interochanteric osteotomy on Legg-Calvé-Perthes disease. J Bone Joint Surg Am. 1985;67:213-236.

All electronic documents accessed May 15, 2010.

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From the June 01, 2010 Issue of Clinical Advisor

Topics:

Orthopedics Pediatrics