Management of knee deformities in children with arthrogryposis.

Arthrogryposis includes heterogeneous disorders, characterized by congenital contractures of multiple joints. Knee involvement is very common (38-90 % of patients with amyoplasia) ranging from soft-tissue contractures (in flexion or hyperextension) to subluxation and dislocation. Flexion contractures are more common and disabling and show significant resistance to treatment and rate of recurrence. Surgical procedures vary with severity of contracture and patient age and include soft-tissue release, femoral shortening-extension osteotomy, gradual correction with Ilizarov, and femoral anterior epiphysiodesis. The presence of pterygium greatly complicates treatment, given the high rate of complications reported. Hyperextension deformities (recurvatum, anterior subluxation, and dislocation) have better prognosis for walking ability. Surgical options include percutaneous (or mini-open) quadriceps tenotomy, open quadricepsplasty, and femoral shortening osteotomy with limited arthrotomy. Knee dislocations usually require surgery and should be reduced early.