RESUMEN
PURPOSE: Early diagnosis and treatment of slipped capital femoral epiphysis (SCFE) is important to prevent slip progression and avoid complications. We sought to determine if MRI findings in patients with unilateral SCFE could indicate 'pre-slip' or predict future SCFE in the contralateral hip. METHODS: A prospective study evaluated patients with unilateral SCFE over a two-year period. MRI of the asymptomatic hip was performed within the perioperative period. Patients were followed with radiographs until a contralateral slip occurred or until physeal closure. Demographics, clinical stability, severity, posterior slope angle (PSA), modified Oxford Bone Score (mOBS) and patency of the triradiate cartilage were recorded and statistical analysis performed. RESULTS: In all, 33 of 54 patients with unilateral SCFE were enrolled into the study. In all, 29 (87.8%) had complete follow-up. Five of the enrolled patients (15.2%) developed a sequential slip requiring in situ pinning. Six of 33 (18.2%) patients had positive MRI findings: four of which proceeded to sequential SCFE and two which did not. One sequential slip had a negative MRI. PSA predicted 1/11 sequential slips (sensitivity 9.09%, specificity 81.4%, positive predictive value (PPV) 11.1%, negative predictive value (NPV) 77.8%) and mOBS predicted 5/11 sequential slips (sensitivity 45.5%, specificity 93%, PPV 62.5%, NPV 87%). An open triradiate cartilage was present in 8/11 patients with sequential slips (sensitivity 72.7%, specificity 81.4%, PPV 50%, NPV 92.1%). CONCLUSION: MRI findings consistent with 'pre-slip' were present in 66.7% of patients who developed a sequential SCFE. Further study on the utility/sensitivity of MRI in predicting sequential SCFE is warranted. LEVEL OF EVIDENCE: II, diagnostic.
RESUMEN
PURPOSE: Treatment of slipped capital femoral epiphysis (SCFE), including the modified Dunn procedure, restores anatomy with significant risk for avascular necrosis (AVN), if performed in the setting of moderate to severe, stable SCFE. The Imhauser osteotomy has been shown to be an effective way to correct residual deformity without the risk of AVN. We sought to evaluate the effectiveness and safety of a combined Imhauser osteotomy and osteochondroplasty, performed via a surgical hip dislocation approach for the acute and delayed treatment of stable SCFE. METHODS: A retrospective review was performed on a series of patients who underwent Imhauser osteotomy and osteochondroplasty via surgical hip dislocation for treatment of chronic, stable SCFE. Patients were divided into acute or delayed treatment groups based on whether osteotomy was performed as the initial slip treatment. RESULTS: In total 19 patients (15 male, four female, average age 13.7 years) were reviewed. Six osteotomies were performed acutely in combination with in situ pinning, 13 were delayed at least six months after in situ pinning (average 21.7 months). Two hips had labral tears that required repair. The mean follow-up was 61 months (23 to 120) (delayed) and 53 months (27 to 61) (acute). The average improvement in slip angle was 40.7° (delayed) and 50.2° (acute) (p = 0.0916), final post-operative slip angle averaged 15.8° (delayed) and 17.8° (acute) (p = 0.544). Femoral neck length and greater trochanteric height were similar between both groups. Average alpha angle at final follow-up measured 55.8° (delayed) and 60.8° (acute) (p = 0.542). No cases of AVN were identified. CONCLUSION: Imhauser osteotomy combined with osteochondroplasty via surgical hip dislocation approach is a safe and effective treatment of moderate to severe, stable SCFE performed in both the acute and delayed setting.
