Evaluation of component positioning in primary total hip arthroplasty using an imageless navigation device compared with traditional methods.

Acetabular orientation affects the success of total hip arthroplasty. Computer-assisted navigation systems may reduce positional errors. Total hip arthroplasty results were analyzed using an imageless navigation system. We hypothesized that reliability and accuracy would improve. One hundred forty-nine total hip arthroplasties were performed using minimally invasive surgical techniques in 3 cohorts: manual (n = 53), initial navigation cases (n = 49), navigation second series (n = 47). Manual patients' cup orientation variation from desired range was -19 degrees to +18 degrees anteversion (SD, 9.1 degrees ), -11 degrees to +25 degrees abduction (SD, 6.7 degrees ). Navigation variation from desired was -18 degrees to +15 degrees (SD, 7.3 degrees ) in group 1 and -15 degrees to +9 degrees (SD, 5.9 degrees ) in group 2 in anteversion and -15 degrees to +13 degrees (SD, 6.1 degrees ) in group 1 and -15 degrees to +11 degrees (SD, 4.7 degrees ) in group 2 in abduction. Results were statistically significant. There were significant differences for operating room time and estimated blood loss, but not incision size or body mass index. Navigation provided controlled, reproducible acetabular alignment; but a learning curve existed in terms of accuracy, estimated blood loss, and operating room time.

The effect of preoperative planning and impaction grafting surgical technique on intraoperative and postoperative complication rate for femoral revision patients with moderate to severe bone loss mean 4.7-year results.

This study reports the results of 41 revision hips, implanted by a single surgeon using impaction grafting (mean follow-up, 4.7 years). All hips had Paprosky scores of III or IV. Harris hip scores improved from 43 to 82. There was 1 intraoperative and 2 postoperative fractures. A single stem was revised during the study. Radiographic review showed the 40 unrevised stems to be stable, and graft incorporation was seen in at least 1 zone in 100% of the femurs. There was no stem subsidence greater than 2.5 mm. The results of this study demonstrate that preoperative planning and a surgical technique, which emphasizes femoral support and vigorous impaction grafting, resulted in an acceptable incidence of complications.