Eccentric reductions may become concentric through femoral head ‘docking’ (FHD) following closed reduction (CR) for developmental dysplasia of the hip (DDH). However, changes regarding position and morphology through FHD are not well understood. We aimed to assess these changes using serial MRI. We reviewed 103 patients with DDH successfully treated by CR and spica casting in a single institution between January 2016 and December 2020. MRI was routinely performed immediately after CR and at the end of each cast. Using MRI, we described the labrum-acetabular cartilage complex (LACC) morphology, and measured the femoral head to triradiate cartilage distance (FTD) on the midcoronal section. A total of 13 hips with initial complete reduction (i.e. FTD < 1 mm) and ten hips with incomplete MRI follow-up were excluded. A total of 86 patients (92 hips) with a FTD > 1 mm were included in the analysis.Aims
Methods
The aim of this study was to investigate the
incidence of dysplasia in the ‘normal’ contralateral hip in patients
with unilateral developmental dislocation of the hip (DDH) and to
evaluate the long-term prognosis of such hips. A total of 48 patients
(40 girls and eight boys) were treated for late-detected unilateral
DDH between 1958 and 1962. After preliminary skin traction, closed
reduction was achieved at a mean age of 17.8 months (4 to 65) in
all except one patient who needed open reduction. In 25 patients
early derotation femoral osteotomy of the contralateral hip had been
undertaken within three years of reduction, and later surgery in
ten patients. Radiographs taken during childhood and adulthood were
reviewed. The mean age of the patients was 50.9 years (43 to 55)
at the time of the latest radiological review. In all, eight patients (17%) developed dysplasia of the contralateral
hip, defined as a centre-edge (CE) angle <
20° during childhood
or at skeletal maturity. Six of these patients underwent surgery
to improve cover of the femoral head; the dysplasia improved in
two after varus femoral osteotomy and in two after an acetabular
shelf operation. During long-term follow-up the dysplasia deteriorated
to subluxation in two patients (CE angles 4° and 5°, respectively)
who both developed osteoarthritis (OA), and one of these underwent
total hip replacement at the age of 49 years. In conclusion, the long-term prognosis for the contralateral
hip was relatively good, as OA occurred in only two hips (4%) at
a mean follow-up of 50 years. Regular review of the ‘normal’ side
is indicated, and corrective surgery should be undertaken in those
who develop subluxation. Cite this article: