Treatment of Posterior Hip Dislocation due to Juvenile Idiopathic Arthritis. Report of Two Cases.

Abstract

Juvenile idiopathic arthritis ( JIA) is a persistent autoimmune-inflammatory disease that affects children younger than 16. Aggressive synovitis of the hip may cause joint destruction, hip protrusion, erosion, pseudosubluxation, dysplasia, and osteoarthritis. Subluxation of the hip had been reported previously. However, dislocation of the hip in JIA is an extremely rare situation, and only two cases have been reported up to date. Reduction of the dislocated hip has to be performed in any way. However, there is no algorithm to be followed for the treatment of hip dislocations caused by JIA. In this study, we presented two cases of hip dislocation caused by JIA.Case 1: An 11-year-old boy had JIA and chronic recurrent multifocal osteomyelitis (CRMO). X-rays and computed tomography (CT) revealed a posterior dislocation of the left hip. An urgent operation was planned for the reduction of the hip. Avascular necrosis, dysplasia, or erosions were not evident at the last follow-up.Case 2: An 11-year-old girl was referred to the hospital with excessive left hip pain starting 24 h ago. A limited synovectomy with joint irrigation was performed. However, pathological examination of the synovium showed chronic inflammation consistent with JIA. On the post-operative 10th day, the patient was consulted for an increase in hip pain and deformity of the left hip. X-rays and MRI revealed posterior dislocation of the left hip with synovial hypertrophy. An urgent operation was planned. The hip could be reduced under anesthesia with mild traction, and a pelvipedal cast was applied only for 3 weeks. Avascular necrosis, dysplasia, destruction, or erosions were not evident at the last follow-up. For early diagnosed patient reduction under anesthesia and medial soft-tissue contracture release; for late diagnosed patient medial soft-tissue contracture release, capsulotomy and synovectomy were effective to prevent destruction and early degenerative changes of the hip joint for treatment of dislocation caused by JIA.