The aim of this study was to evaluate the correlation between
Salter’s criteria and Kalamchi’s classification of avascular necrosis
in patients treated for developmental dysphasia of the hip (DDH). The study involved a retrospective analysis of 123 patients (123
hips) with DDH treated by operative and non-operative reduction
before the age of two years, with a minimum follow-up of ten years.
Salter’s criteria (S1 to S4) were determined from radiographs obtained
at one to two years post-reduction, whilst the Kalamchi grade was determined
from radiographs obtained at ten or more years of age. Early post-reduction
radiographs were also used to evaluate the centre-head distance
discrepancy (CHDD) and the occurrence of a dome-shaped deformity
of the proximal femoral metaphysis (D-shaped metaphysis). The prognosis was described as good (Kalamchi grade K0 or KI),
fair (Kalamchi grade KII) or poor (Kalamchi grade KIII or KIV) for
analysis and correlation with the early Salter criteria, CHDD and
D-shaped metaphysis.Aims
Patients and Methods
We reviewed the medical records of 115 patients with 130 hips with developmental dysplasia with complete dislocation in the absence of a neuromuscular disorder, spontaneous reduction with a Pavlik harness, and a minimum of 14 years’ follow-up. The mean age at the time of harness application was 4.8 months (1 to 12) and the mean time spent in the harness was 6.1 months (3 to 12). A total of 108 hips (83.1%) were treated with the harness alone and supplementary surgery for residual acetabular dysplasia, as defined by an acetabular index >
30°, was performed in 22 hips (16.9%). An overall satisfactory outcome (Severin grade I or II) was achieved in 119 hips (91.5%) at a mean follow-up of 16 years (14 to 32) with a follow-up rate of 75%. Avascular necrosis of the femoral head was noted in 16 hips (12.3%), seven of which (44%) underwent supplementary surgery and nine (56%) of which were classified as satisfactory. The acetabular index was the most reliable predictor of residual acetabular dysplasia.
We performed a paired study of mature patients with Perthes’ disease to compare the radiological results after treatment between conservatively- and surgically-treated groups. One patient was selected from each group to create the pairs for this study. Each pair was strictly matched for gender, body mass index, age at onset, stage at the first visit, necrotic area and radiological at-risk signs and each was assessed by comparing the values of six radiological measurements. Eighteen pairs (36 hips) fitted the criteria. The radiological measurements which showed a statistically better result in the surgical groups were Mose’s method, the acetabular-head index and leg-length discrepancy. There were no statistical differences in the slope of the acetabular roof and the articulotrochanteric distance. Four hips in the conservative group were in Stulberg class II, five in class III and nine in class IV. In the surgical group, 13 were in Stulberg class II, four in class III and one in class IV. We conclude that surgical treatment improved the sphericity of the femoral head and provided greater acetabular cover, but did not reform the acetabular roof. It was noteworthy that a greater leg-length discrepancy and a smaller articulotrochanteric distance were not seen in the surgical group. Our study suggests that surgical treatment is preferable in patients with severe Perthes’ disease.
