Twenty-two patients who had severe coxa plana had closed reduction for
lateral subluxation of the femoral head, as determined radiographically.
All had painful limitation of motion of the hip that prevented proper
positioning of the femoral head using a brace. The average age when the
patients were first seen was eight years and six months. General anesthesia
was required in order to obtain the reduction, and percutaneous tenotomy of
the adductor longus was done whenever necessary. After the reduction, a
Petrie cast was worn for several months. The length of follow-up averaged
three years and eight months (range, two years to six years and eight
months). Radiographic evaluation at the time of the last follow-up showed
nine hips to be spherically congruent, twelve to be spherically congruent,
and one to be incongruent. Thus, in 95 per cent of the hips, a congruent
joint was obtained using this method of treatment. These results strongly
support the concept that all treatment should be directed at containing the
femoral head within the acetabulum during the clinically active phase of
coxa plana.