Case Study: Novel Approach to Treatment of Slipped Capital Femoral Epiphysis B.A. MacWilliams1,2, L.A. Anderson 2, and P.M. Stevens2 1
2
Shriners Hospitals for Children, Salt Lake City, UT USA Dept. of Orthopaedics, University of Utah, Salt Lake City, UT USA E-mail:
[email protected]
PATIENT HISTORY The patient initially presented as an 11+8 year old female with a diagnosis of left slipped capital femoral epiphysis (SCFE). Secondary to the SCFE she was noted to have retroversion and limb length inequality. CLINICAL DATA Pertinent to the diagnosis, on her involved side, this subject demonstrated limited hip flexion of 90°, limited hip inward rotation of -25° (70° less than typically developing) and outward rotation of 70° (40°> typically developing). The subject also presented with weakness about the hip > 2 standard deviations from typically developing based on her age and BMI as measured with hand held dynamometry (her uninvolved side had normal strength). Her BMI was 28 (97% percentile). Her left leg was 2.5 cm shorter than her right. Deficits in functional walking and disability questionnaires were also noted and are presented in Table 1. MOTION DATA Gait data at the initial visit immediately prior to surgery demonstrated excessive frontal plane trunk and pelvic motions and left protracted right retracted trunk and pelvis rotations. Her involved side demonstrated: 1) large external hip rotation, particularly at initial contact, 2) knee was locked in full extension during stance, and 3) external foot progression secondary to hip rotation. Involved side hip flexion and abduction patterns were grossly normal as were velocity, cadence and stride lengths. Her uninvolved side demonstrated excessive hip abduction, hip flexion, and knee flexion in stance. Gait Deviation Index (GDI) scores were 63 on the left and 80 on the right. TREATMENT DECISIONS AND INDICATIONS As a result of the noted retroversion, a left distal femoral derotational osteotomy (FDRO) was performed. Operative notes indicated the 45° of surgical correction. Distal femoral epiphysiodesis was also performed on the Right (uninvolved) side to equalize leg lengths. Her femoral head was also pinned at this time to stabilize the slip as it had not been previously treated. OUTCOME The patient was seen 15 months after surgery for follow-up evaluation. Improved hip flexion and hip rotational profile were noted on physical exam (Table 1). Strength improved to within normal limits. Marked improvements in functional questionnaires were reported. Follow up gait analysis demonstrated that abnormal trunk and pelvic motions were
eliminated and the pelvis shifted into a more posteriorly tilted position. The involved hip showed improved, but not normalized rotation and hip flexion was shifted into more extension secondary to the change in pelvic tilt. GDI improved 15 points on the left to 78 and 19 points on the right to 99. Table 1: *Data for involved side (Left), FMS = Functional Mobility Score. Physical Exam Hip Flexion* Hip Inward Rotation* Hip Outward Rotation* Walking Walking Endurance FMS 5m FMS 50m FMS 500m PODCI Upper Extremity Transfers Sports Comfort/Pain Global Happiness Gait Deviation Index Left Right
Pre-Op 90° -25° 70°
Post-Op 120° 20° 40°
¼ mile 5 3 (crutches) 3 (crutches)
No limit 6 6 6
96 55 31 17 50 75
100 100 92 100 98 100
63 80
78 99
SUMMARY SCFE is typically treated by initial pinning to stop the slip and then by corrective surgery if indicated to address the deformity. Most commonly this involves an intertrochanteric valgus and flexion osteotomy. In our experience the acquired retroversion of the hip is often underappreciated. Our current approach, which is now being prospectively studied, is to only correct the retroversion with a distal FDRO over an intramedullary rod. Subjects may require subsequent surgery to address impingement issues, but this can be done arthroscopically. The current approach obviates the need for femoral neck surgery which has risk factors including necrosis. This subject demonstrated marked improvements with FDRO including elimination of compensatory trunk and pelvis frontal motions and rotational offsets. Uninvolved side compensations were completely eliminated and improvements at her involved side hip and knee were notable. These kinematic changes translated into functional improvements as noted by endurance, FMS and PODCI scores. Complete correction of her hip rotational profile and hip rotation during walking were not achieved despite a 45° correction during surgery, highlighting the magnitude of the deformity. Further correction in this case by arthroscopic FAI chondroplasty may be warranted DISCLOSURE STATEMENT None of the authors have conflicts of interest to disclose.
