Long-term results of intertrochanteric varus osteotomy for dysplastic osteoarthritis of the hip.

The beneficial role of intertrochanteric varus or valgus osteotomy in the treatment of hip osteoarthrosis has been recognised since the 1920s. Even today, it has an important role to delay the need for hip replacement in younger patients. The purpose of this study was to evaluate the long-term results of intertrochanteric varus osteotomy for dysplastic osteoarthritis of the hip. Between 1980 and 1995, 52 hips with dysplastic osteoarthritis underwent an intertrochanteric varus osteotomy. All patients could be followed up after 17.8 years. Radiographic assessment included centre-edge (CE) angle of Wiberg and collodiaphyseal (CCD) angle. Dysplastic hip dislocation was classified according to Crowe. Osteoarthritis was graded according to Tönnis. Preoperative osteoarthritis was Tonnis grade 1 in 19 hips, grade 2 in 28 and grade 3 in five. Complications were also documented. Clinical evaluation included score according to Merle d'Aubigné, Harris Hip Score and range of motion. Six of 52 patients underwent total hip replacement (THR) within five years after intertrochanteric osteotomy. In these cases, preoperative osteoarthritis was grade 3 in four cases and grade 2 in one case according to Tönnis. Twenty-five of 52 patients underwent THR after an interval of five to ten years after intertrochanteric osteotomy. In these cases, preoperative osteoarthritis was grade 3 in one case and grade 2 in 24 cases according to Tönnis. Sixteen of 52 patients underwent THR after an interval of ten to 15 years after intertrochanteric osteotomy. In these cases, preoperative osteoarthritis was grade 2 in four cases and grade 1 in 12 cases according to Tönnis. In five patients the hip was functioning well after a period longer than 15 years. In all these cases osteoarthritis was grade 1 according to Tönnis. In 40.4% of patients, THR was delayed longer than ten years. The osteotomy performed well at a mean time of 9.7 years after the procedure (range 3-21). Intertrochanteric varus osteotomy for dysplastic osteoarthritis of the hip should be considered in early or mild osteoarthritic changes of the hip. Good prognosis with delay of THR of more than ten years can be expected to exceed 40%, even when indications are less than optimum.