We investigated the incidence and risk factors
for the development of avascular necrosis (AVN) of the femoral head in
the course of treatment of children with cerebral palsy (CP) and
dislocation of the hip. All underwent open reduction, proximal femoral
and Dega pelvic osteotomy. The inclusion criteria were: a predominantly
spastic form of CP, dislocation of the hip (migration percentage,
MP >
80%), Gross Motor Function Classification System, (GMFCS) grade
IV to V, a primary surgical procedure and follow-up of >
one year. There were 81 consecutive children (40 girls and 41 boys) in
the study. Their mean age was nine years (3.5 to 13.8) and mean
follow-up was 5.5 years (1.6 to 15.1). Radiological evaluation included
measurement of the MP, the acetabular index (AI), the epiphyseal
shaft angle (ESA) and the pelvic femoral angle (PFA). The presence
and grade of AVN were assessed radiologically according to the Kruczynski
classification. Signs of AVN (grades I to V) were seen in 79 hips (68.7%). A
total of 23 hips (18%) were classified between grades III and V. Although open reduction of the hip combined with femoral and
Dega osteotomy is an effective form of treatment for children with
CP and dislocation of the hip, there were signs of avascular necrosis
in about two-thirds of the children. There was a strong correlation
between post-operative pain and the severity of the grade of AVN. Cite this article:
The recognition of hips at risk of displacement
in children with cerebral palsy (CP) is a difficult problem for
the orthopaedic surgeon. The Gross Motor Function Classification
System (GMFCS) and head–shaft angle (HSA) are prognostic factors
for hip displacement. However, reference values for HSA are lacking.
This study describes and compares the development of HSA in normal
hips and children with CP. We selected 33 children from a retrospective cohort with unilateral
developmental dysplasia of the hip (DDH) (five boys, 28 girls) and
50 children (35 boys, 15 girls) with CP with GMFCS levels II to
V. HSA of normal developing hips was measured at the contralateral
hip of unilateral DDH children (33 hips) and HSA of CP children
was measured in both hips (100 hips). Measurements were taken from
the radiographs of the children at age two, four and seven years.
The normal hip HSA decreased by 2° per year (p <
0.001). In children
with CP with GMFCS levels II and III HSA decreased by 0.6° (p =
0.046) and 0.9° (p = 0.049) per year, respectively. The HSA did
not alter significantly in GMFCS levels IV and V. Between the ages of two and eight years, the HSA decreases in
normal hips and CP children with GMFCS level, II to III but does
not change in GMFCS levels IV to V. As HSA has a prognostic value
for hip displacement, these reference values may help the orthopaedic
surgeon to predict future hip displacement in children with CP. Cite this article:
Proximal femoral varus osteotomy improves the
biomechanics of the hip and can stimulate normal acetabular development
in a dysplastic hip. Medial closing wedge osteotomy remains the
most popular technique, but is associated with shortening of the
ipsilateral femur. We produced a trigonometric formula which may be used pre-operatively
to predict the resultant leg length discrepancy (LLD). We retrospectively
examined the influence of the choice of angle in a closing wedge
femoral osteotomy on LLD in 120 patients (135 osteotomies, 53% male,
mean age six years, (3 to 21), 96% caucasian) over a 15-year period
(1998 to 2013). A total of 16 of these patients were excluded due
to under or over varus correction. The patients were divided into
three age groups: paediatric (<
10 years), adolescent (10 to
16 years) and adult (>
16 years). When using the same saw blades
as in this series, the results indicated that for each 10° of angle
of resection the resultant LLD equates approximately to multiples
of 4 mm, 8 mm and 12 mm in the three age groups, respectively. Statistical testing of the 59 patients who had a complete set
of pre- and post-operative standing long leg radiographs, revealed
a Pearson’s correlation coefficient for predicted This study identified a geometric model that provided satisfactory
accuracy when using specific saw blades of known thicknesses for
this formula to be used in clinical practice. Cite this article:
