We report the clinical and radiological outcome
of subcapital osteotomy of the femoral neck in the management of symptomatic
femoroacetabular impingement (FAI) resulting from a healed slipped
capital femoral epiphysis (SCFE). We believe this is only the second
such study in the literature. We studied eight patients (eight hips) with symptomatic FAI after
a moderate to severe healed SCFE. There were six male and two female
patients, with a mean age of 17.8 years (13 to 29). All patients underwent a subcapital intracapsular osteotomy of
the femoral neck after surgical hip dislocation and creation of
an extended retinacular soft-tissue flap. The mean follow-up was
41 months (20 to 84). Clinical assessment included measurement of
range of movement, Harris Hip Score (HHS) and Western Ontario and McMaster
Universities Osteoarthritis score (WOMAC). Radiological assessment
included pre- and post-operative calculation of the anterior slip
angle (ASA) and lateral slip angle (LSA), the anterior offset angle
(AOA) and centre head–trochanteric distance (CTD). The mean HHS
at final follow-up was 92.5 (85 to 100), and the mean WOMAC scores
for pain, stiffness and function were 1.3 (0 to 4), 1.4 (0 to 6)
and 3.6 (0 to 19) respectively. There was a statistically significant
improvement in all the radiological measurements post-operatively.
The mean ASA improved from 36.6° (29° to 44°) to 10.3° (5° to 17°)
(p <
0.01). The mean LSA improved from 36.6° (31° to 43°) to 15.4°
(8° to 21°) (p <
0.01). The mean AOA decreased from 64.4° (50°
to 78°) 32.0° (25° to 39°) post-operatively (p <
0.01). The mean
CTD improved from -8.2 mm (-13.8 to +3.1) to +2.8 mm (-7.6 to +11.0)
(p <
0.01). Two patients underwent further surgery for nonunion.
No patient suffered avascular necrosis of the femoral head. Subcapital osteotomy for patients with a healed SCFE is more
challenging than subcapital re-orientation in those with an acute
or sub-acute SCFE and an open physis. An effective correction of
the deformity, however, can be achieved with relief of symptoms
related to impingement. Cite this article:
