The purpose of the study is to evaluate the retrospective results of 92 surgically treated spastic hips. Twenty-one patients were able to walk in the community with aids, 19 were able to walk about the house, and 13 were wheelchair bound. The mean age at the time of the operation was 7 yrs (3–18) and the average follow-up was 5. The cohort of the study included 45 tetraplegic patients, 6 diplegic, and 2 hemiplegic. The dislocated hips were 25 and the subluxated ones 67.

The surgical treatment included soft tissue and bone procedures. The 53 patients were divided into two age groups: those less than 7yrs old and those older than 7yrs. The cohort was also divided into 39 patients operated in one setting, and 14 operated in more than one. Clinical evaluation was based on the joint range of motion, the ambulatory status and the pain. The radiological evaluation criteria were based on Reimer's migration index, the center-edge angle, Sharp's angle, and neck-femoral angle. We used the interclass correlation coefficient to measure our interobserver reliability for MI 0,93, for CE angle 0,95 and for Sharp's angle 0,81, as the interobserver difference for MI averaged 9% for CE angle 7and for Sharp's angle 3.

Statistical analysis of continuous variables was done by Student's t-test or the Wilcoxon rank sum test. Categorical variables were evaluated by Fisher's test. Concerning the walking ability, from the 13 severe quadriplegic patients, none improved his functional level but they achieved better sitting balance. The walking ability of the rest of the patients improved one level in 78% of the cases. The mean preoperative abduction was improved from 24,7 to 33,5, the mean flexion was slightly reduced from 123 preoperatively to 114 postoperatively and the mean extension reduced from −20 preoperatively to −8 postoperatively. Reimer's index reduced from 67,2 to 21,7 postoperatively, the CE angle increased from −10,6 to 20,5, the Sharp's angle increased from 36,9 to 40,5 and the neck-shaft angle increased from 119,7 to 157,5post-operatively. Of greater significance were MI and CE at p<0.05. A migration index of >50% at final follow-up was associated with a worse migration index and a worse CE angle at 1 year post-operatively. 46 hips were evaluated as good, 30 as satisfactory, and 16 as poor. The severe tetraplegic with small-negative CE angle and Reimer's migration index > 50%, as well as the small age of the patients (<7 yrs) were negative prognostic factors. Better results were observed when patients were operated at age <7yrs by soft tissue procedures and MI<30%, while patients >7yrs had satisfactory results only after combined bony and soft tissue procedures and MI <50%. A migration index of >50% at final follow-up was associated with a worse migration index and a worse CE angle at 1 year postoperatively.