Abstract
Purpose
The outcome of idiopathic chondrolysis in South Africa has been reported as a progressive downhill course resulting in a painful, stiff hip (Jones 1971, Sparks&Dall 1982). The cause of the disease remains unknown. Theories suggested are mechanical (decreased movement with loss of synovial nutrition; increased joint pressure) and an auto-immune response in genetically predisposed individuals. Our experience with continuous passive motion (CPM) and anti-inflammatory treatment has been disappointing.
Method
In order to improve our understanding of the disease and our results, we prospectively studied 5 consecutive patients. All the patients had a subtotal capsulectomy (Roy&Crawford 1988) to relieve intra-articular pressure and correction of the flexion and abduction deformities. Post-operative treatment was with anti-inflammatories and CPM
Results
The patients were adolescent females between 10 and 12.5 years old. They presented with stiff, painful hips with flexion, abduction and external rotation deformities. They had normal auto-immune markers. Radiographs revealed osteopenia and joint space narrowing. CT confirmed osteopenia and joint space narrowing. Three patients had subchondral erosions (two on either side of the joint and one on the acetabular side only). MRI showed bone oedema and confirmed the erosions.
Histology of the synovium showed non-specific chronic inflammation with lymphocyte and plasma cell infiltration suggesting an auto-immune cause. Histology of the cartilage showed a superficial layer of fibrous tissue, then a layer of degenerate chondrocytes, with normal chondrocytes in the deep layer. Post-operatively patients had improved range of motion. At mean follow up of 7.8 months the patients had a repeat MRI to assess cartilage regeneration.
NO DISCLOSURES
