The fate of hips that are not prophylactically pinned after unilateral slipped capital femoral epiphysis.

ABSTRACT

BACKGROUND: The indications for prophylactic pinning of the contralateral hip after unilateral slipped capital femoral epiphysis (SCFE) remain controversial in part because the natural history of the contralateral hip is unclear. QUESTIONS/PURPOSES: We therefore determined (1) the incidence of contralateral slips in patients with unilateral SCFE, (2) the rate of subsequent corrective surgery, and (3) the Harris hip score (HHS) and VAS pain score for hips that sustained a contralateral slip after unilateral pinning. METHODS: We retrospectively reviewed 226 patients with unilateral SCFE at initial presentation between 1965 and 2005; of these, 133 met our inclusion criteria and were followed at least 2 years. Latest followup included examination and radiographs for 52 patients and HHS (without radiographs) and VAS pain score for 81 hips. Minimum followup was 2 years (median, 13 years; range, 2-43 years). RESULTS: Of the 133 patients at risk for a subsequent slip, 20 patients developed a contralateral slip (15%). One patient developed avascular necrosis requiring arthroplasty, and another patient had a mild contralateral slip with disabling pain. For the 15 patients with contralateral slips and scores available, the mean HHS was 90 (range, 49-100) and the mean VAS pain score was 20 of 100. Six found the contralateral hip painful. CONCLUSIONS: The contralateral slip sustained by the majority of patients was for the most part mild. However, nearly 1/3 of the contralateral slipped hips were painful. One patient has severe pain, and a second required THA for avascular necrosis after an unstable slip. These may have been preventable by prophylactic pinning. LEVEL OF EVIDENCE Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.