Late correction of neck deformity in healed severe slipped capital femoral epiphysis: short-term clinical outcomes.

PURPOSE: Contemporary methods for the management of neck deformity following a healed severe slipped capital femoral epiphysis (SCFE) include subcapital neck osteotomy.

METHODS

18 patients with chronic severe SCFE in the oblique plane (mean slip angle = 70°) constituted the study group. 6 patients with an open physis underwent modified Dunn capital realignment and 12 patients with a closed physis underwent surgical dislocation with a corrective neck osteotomy. 10 patients already had an in-situ pinning.

RESULTS

The mean follow-up was 4.5 years (3-6 years). The mean preoperative modified Harris Hip Score (mHHS) and nonarthritic hip score (NAHS) were 24 and 40 respectively, followed by a score of 89 and 92 respectively at the last follow-up (p = 0.0002). Radiologically, all the parameters showed a significant correction. The mean pre- and postoperative values of alpha angle were 79.8 and 34.5 respectively (p = 0.0002); AP slip angle being 36.7 and 14.8 (p = 0.002); lateral slip angle being 54.2 and 13.6 (p = 0.0002); oblique plane slip angle being 70.7 and 20.8 (p = 0.0002) and centre trochanter distance being -6.9 and 1.2 (p = 0.002). The major complications seen were nonunion of the neck osteotomy (n = 1/12) and chondrolysis (n = 1/6) in the modified Dunn's group. The overall complication rate was 11%. There was no statistically significant difference in outcome between the 2 groups clinically and radiologically.

CONCLUSIONS

Femoral neck osteotomy is a potentially rewarding technique to correct severe neck deformities and restoring hip function in the short term.