Two-stage surgery in the treatment of spastic hip dislocation--comparison between early and late results of open reduction and derotation-varus femoral osteotomy combined with Dega pelvic osteotomy preceded by soft tissue release.

BACKGROUND: Authors present and compare early and late results of treatment of spastic hip dislocation in cerebral palsy patients.
MATERIAL AND METHODS: We analyzed a group of 77 patients (109 hips) with hip joint dislocation (MP>80%). The patients were divided into two groups: <3 years of follow-up vs. > 3 years of follow-up. The first group thus included 64 hips (47 patients) with mean follow-up duration of 2.2 years (range 1.1-3), and the second group had 45 hips (30 patients) with mean follow-up duration of 4.8 years (range 3.2-10.2). The hips were evaluated clinically and radiographically. The relation of the femoral head to the acetabulum was described as the Acetabular Index (AI) and Reimers' migration percentage (MP).
RESULTS: In Group I, AI improved from 32.2°(17°-50°) to 22.2°(6°-45°), MP improved from 98.9% (82%-100%) to 15.9% (0%- 100%). In Group II, AI improved from 28.9° (10°-62°) to 19.4° (3°-50°). The changes in AI and MP were statistically significant. Group I demonstrated a reduction in the flexion contracture from 21.1° (0°-50°) to 10.7° (0°-30°), an increase in abduction from 19.5° (0°-60°) to 29.9° (0°-60°), and a decrease in the popliteal angle from 52.0° (0°-100°) to 34.2° (0°-85°). Group II showed a reduction in the flexion contracture from 24.6° (0°-60°) to 12.6° (0°-40°), an increase in abduction from 17.3° (-25°-80°) to 26.1° (-15°-80°), and a decrease in the popliteal angle from 61.4° (0°-120°) to 40.7° (10°-100°). These improvements were statistically significant.
CONCLUSION: Open reduction of the hip joint combined with derotation-varus femoral osteotomy and Dega pelvic osteotomy is a very effective treatment in spastic hip joint dislocation. We observed no statistically significant deterioration of results between the groups.