Salter innominate osteotomy is an effective reconstructive
procedure for the treatment of developmental dysplasia of the hip
(DDH), but some children have a poor outcome at skeletal maturity.
In order to investigate factors associated with an unfavourable
outcome, we assessed the development of the contralateral hip. We retrospectively
reviewed 46 patients who underwent a unilateral Salter osteotomy
at between five and seven years of age, with a mean follow-up of
10.3 years (7 to 20). The patients were divided into three groups
according to the centre–edge angle (CEA) of the contralateral hip
at skeletal maturity: normal (>
25°, 22 patients), borderline (20°
to 25°, 17 patients) and dysplastic (<
20°, 7 patients). The
CEA of the affected hip was measured pre-operatively, at eight to
nine years of age, at 11 to 12 years of age and at skeletal maturity.
The CEA of the affected hip was significantly smaller in the borderline
and dysplastic groups at 11 and 12 years of age (p = 0.012) and
at skeletal maturity (p = 0.017) than in the normal group. Severin
group III was seen in two (11.8%) and four hips (57.1%) of the borderline
and dysplastic groups, respectively (p <
0.001). Limited individual development of the acetabulum was associated
with an unfavourable outcome following Salter osteotomy. Cite this article:
Two types of fracture, early and late, have been
reported following limb lengthening in patients with achondroplasia (ACH)
and hypochondroplasia (HCH). We reviewed 25 patients with these conditions who underwent 72
segmental limb lengthening procedures involving the femur and/or
tibia, between 2003 and 2011. Gender, age at surgery, lengthened
segment, body mass index, the shape of the callus, the amount and
percentage of lengthening and the healing index were evaluated to determine
predictive factors for the occurrence of early (within three weeks
after removal of the fixation pins) and late fracture (>
three weeks
after removal of the pins). The Mann‑Whitney U test and Pearson’s
chi-squared test for univariate analysis and stepwise regression
model for multivariate analysis were used to identify the predictive factor
for each fracture. Only one patient (two tibiae) was excluded from
the analysis due to excessively slow formation of the regenerate,
which required supplementary measures. A total of 24 patients with
70 limbs were included in the study. There were 11 early fractures in eight patients. The shape of
the callus (lateral or central callus) was the only statistical
variable related to the occurrence of early fracture in univariate
and multivariate analyses. Late fracture was observed in six limbs
and the mean time between removal of the fixation pins and fracture
was 18.3 weeks (3.3 to 38.4). Lengthening of the tibia, larger healing
index, and lateral or central callus were related to the occurrence
of a late fracture in univariate analysis. A multivariate analysis
demonstrated that the shape of the callus was the strongest predictor
for late fracture (odds ratio: 19.3, 95% confidence interval: 2.91
to 128). Lateral or central callus had a significantly larger risk
of fracture than fusiform, cylindrical, or concave callus. Radiological monitoring of the shape of the callus during distraction
is important to prevent early and late fracture of lengthened limbs
in patients with ACH or HCH. In patients with thin callus formation,
some measures to stimulate bone formation should be considered as
early as possible. Cite this article:
