Knee pain as the initial symptom of slipped capital femoral epiphysis: an analysis of initial presentation and treatment.

A retrospective review was performed of 106 patients to determine the effect of knee pain as the initial complaint of slipped capital femoral epiphysis (SCFE). Sixteen (15%) patients had a primary complaint of distal thigh or knee pain or both at initial presentation to our institution or to a referring physician. Ninety (85%) patients described primarily hip, groin, or proximal thigh discomfort. Of the 106 patients with SCFE, 65 patients received no operative treatment before being evaluated at our institution and were the subject of the remainder of the study. Of these, 15 (23%) patients had distal thigh or knee pain or both as their chief complaint (group I), and 50 (77%) patients had hip, groin, or proximal thigh pain (group II). There was no difference between the groups with respect to age, gender, or slip stability. Group I patients were more likely to receive a misdiagnosis (p < 0.05) and undergo unnecessary or uninformative radiographs (p < 0.05). Additionally, patients in group I were found to have slips of greater radiographic severity (p < 0.05). Although not statistically significant, there was a trend for group I patients to experience a longer delay to diagnosis and to require a proximal femoral osteotomy as treatment for their slips. We conclude that isolated distal thigh or knee pain or both is a common presentation of SCFE. Furthermore, this symptom complex, when compared with the more classic presentation of SCFE, leads to higher rates of unnecessary radiographs, misdiagnoses, and severe slips, potentially increasing long-term morbidity.