The bone-vacuum cementing technique for the fixation of the stem in total hip arthroplasty.
The bone-vacuum cementing technique is a promising method developed to obtain reliable fixation of the femoral component. Previous studies showed that intraoperative embolic complications, cardiopulmonary impairment, and deep venous thrombosis can be prevented when this technique is used. The specific aims of the present investigation were to provide additional treatment outcome information, to identify risk factors for poor results, and to define the need of surgical technique improvement by risk factor analysis. The first 118 consecutive patients (121 hips) who had primary total hip arthroplasty using the bone-vacuum cementing technique and an anatomical stem were followed-up for a mean of 2.5 years (1 to 4 years). The mean age of patients at index operation was 73 years. Current criteria were used for clinical and radiological assessment. At the time of the latest follow-up, 3 patients (3 hips, 2.5%) had been lost, and 9 patients (9 hips, 7.5%) had died. However, the status of the hip joint at the time of death could be verified in all patients. Thus, the clinical outcome of 115 patients (118 hips, 97.5%) was known. Radiographs were available for 102 patients (104 hips) who were alive for the entire follow-up period. The mean preoperative Harris Hip Score was rated 51, and it had improved to 92 at the time of follow-up. The score was good for 70 hips and excellent for 42 hips, so the rate of clinical success was 95%. Six patients (6 hips, 5%) had a fair result. Two of them had a fracture of the greater trochanter after the index operation, requiring internal fixation. Four hips with severe acetabular dysplasia had persistent limp and limited motion. The quality of the cement mantle was rated good (grade A and B) in 108 of 121 hips (89.5%). Nineteen of the 108 hips presented at least one small void in the cement mantle (grade C1). Insufficient thickness of the cement mantle (grade C2) was present in 10 hips (8%). Failure of cement to extend below the tip of the stem (grade D) was observed in the remaining 3 hips (2.5%). In the present series no femoral component required revision because of aseptic loosening, and there was no radiographic evidence of aseptic loosening at follow-up. Radiolucencies without progression were found in Gruen zone 1 in 11 of 104 hips (10.6%), and in zone 7 in 7 hips (6.7%). In one hip (0.9%) ballooning osteolysis was observed in zone 7. Seventy-five hips (72%) had either no change in femoral bone density or only patchy loss of bone density isolated to Gruen zones 1 and 7. Twenty-nine hips (28%) had some reduction of bone density isolated to zones 1 and 7. A slight cortical hypertrophy was seen in 4 hips (3.8%). Of the whole series, one hip required revision surgery because of septic loosening 2 years after the index operation. At an average of 2.5 years postoperatively, the femoral component inserted using the bone-vacuum technique functioned well overall, and patient satisfaction was high. Clinical and radiological results do not contrast with those achieved using contemporary cementing techniques.