Arthrodiastasis for late onset Perthes' disease using a simple frame and limited soft tissue release: early results.

Perthes' disease (Legg-Calvé-Perthes' disease) is relatively common in childhood, affecting 0.8/100.000 children. Late onset Perthes' disease, older than 8 years of age, constitutes about 20% of cases and is known for its aggressive course and poor outcome with chronic hip pain and stiffness. Although containment of the head in the acetabulum is the usual treatment for early cases, its results in treating late-onset cases are universally poor, so that many authors conclude that there is an upper age limit for effectiveness of containment treatment. The emerging philosophy of hip distraction (arthrodiastasis) with release of contractured muscle groups around the hip may be a new concept for treatment of late onset Perthes' disease. Thirty children with late-onset Perthes' disease (age > 8 years) presenting to the orthopaedic department at Sporting Health Insurance Student Reference Hospital - Alexandria, Egypt, between December 2004 till November 2008 were treated by hip arthrodiastasis using minimal soft tissue release and a simple Ilizarov construct. At the end of an average follow-up period of 3.6 years (range: 2-7 years, SD 13) there was an improvement in the range of movement, pain, and superior and lateral subluxation of the head, with a statistically significant difference between pre and post-operative values. Minimal soft tissue release and hip distraction can be regarded as a salvage procedure for late onset Perthes' disease with hip pain, at the stage of necrosis or fragmentation. Furthermore, this method did not result in any alteration in the joint anatomy, thus allowing the possibility for future surgery, if needed.