The aim of this work is to determine the effect of this type
of treatment on the shape of the femoral head, the range of
motion (ROM), radiological changes in the femoral head,
and the prognosis of Perthes disease at skeletal maturity.
From 1998 to 2007, 53 patients with Perthes disease were
treated with a combination of soft tissue release and joint
distraction with a hinged monolateral external fixator in 32
patients and by Ilizarov external fixator in 21 patients.
Nineteen of our 53 patients attained skeletal maturity and
were evaluated in our study. This study included 15 boys
and four girls, mean age at surgery 9.3 years (range
7.2–13.1), and mean age at the last follow-up 17.4 years
(range 14.9–21.3). The duration of symptoms varied from a
period of 6 to 60 months before the operation. Radiographs
taken during the fragmentation stage of the disease were
classified by the lateral pillar classification of Herring; 19 of
our patients attained skeletal maturity and were evaluated.
Clinical assessment included the Harris hip score, hip
ROM, and limb length discrepancy. Radiographic
assessment included sharp transverse acetabular
inclination, the uncoverage percentage, the epiphyseal
index before surgery (modified Eyre–Brook), at frame
removal, and at the last follow-up, the epiphyseal quotient
(of Sjovall), and the Stulberg classification. The mean
follow-up was 7.2 years (range 4.1–11.3). The mean Harris
hip score was 87.1/100 (range 49.2–94.8). An improvement
in hip (ROM) of 83.3% of the normal range was restored.
There was a marked improvement in the degree of pain
and limp postoperatively. The hip ROM was slightly limited
in most patients, and seven patients had limb shortening of
between 1 and 3 cm. The mean sharp transverse
acetabular inclination of the affected side was 448 (range
35–51) compared with 378 for the unaffected side
(P= 0.042). The mean uncoverage percentage was 36%
(range 24–45) compared with 21% for the unaffected side |
