Femoral shaft osteotomy for obligate outward rotation due to SCFE

摘要

Slipped capital femoral epiphysis (SCFE) is an adolescent disease that leads to retroversion of the femoral neck and shaft, relative to the head. Observing that patients with SCFE must walk with an outward foot progression angle and externally rotate the leg in order to flex the hip, we have been performing a femoral shaft rotational osteotomy wherein we rotate the lower femur 45° inward, relative to the upper femur. By correcting retroversion, our goal is to improve functional hip and knee motion, thereby mitigating the effects of SCFE impingement. This is a retrospective review of five hips in four patients (two boys and two girls), average age 14.7 years (range 11 + 7–18 years) who underwent femoral midshaft rotational osteotomy for correction of acquired retroversion of the femur secondary to severe SCFE. We compared clinical findings at the outset to those at an average follow-up of 46 months (range 24–74 months). Pre- and post-gait analysis was performed in three patients. Two of the patients underwent elective arthroscopic osteochondroplasty to alleviate residual FAI: contralateral arthroscopy is pending in one. The first patient in this series received a hip arthroplasty, 62 months after his osteotomy, at age 23. Following midshaft osteotomy, all patients experienced improvement in comfort, gait and activities of daily living. With the patella neutral, they had improved range of hip flexion from an average preoperative flexion of <25° to a postoperative flexion of >90°. Two patients (both male) had delayed union and some loss of correction, secondary to broken interlocking screws; each healed with reamed, exchange nailing. The interlocking screws have since been redesigned and enlarged. Femoral shaft rotational osteotomy restores the functional range of hip motion, while correcting obligate out-toeing and improving knee kinematics. This procedure is technically straightforward, permitting progressive weight bearing, while avoiding the risk of AVN. Osteochondroplasty for residual FAI can be deferred, pending the outcome. Level of evidence III: retrospective series—no controls.