Outcome of an ultrashort metaphyseal-fitting anatomic cementless stem in highly active obese and non-obese patients

Purpose: The purpose of this study was to investigate the clinical and radiographic results and complication rates after cementless total hip arthroplasty using an ultrashort femoral stem in highly active [University of California, Los Angeles (UCLA) activity level above 8 points] obese and non-obese patients.

Methods: A total of 108 patients (138 hips) in the obese group [body mass index (BMI) of 30 kg/m² or greater] and 125 patients (168 hips) in the nonobese group (BMI of 29 kg/m² or less) were enrolled in the study. The mean age was 50.7 ± 11.6 years in the obese group and 48.2 ± 13.0 years in the nonobese group. The mean follow-up was 7.4 years (range six to eight years) and 7.5 years (range six to eight years), respectively.

Results: At the final follow-up, there were no significant differences between the highly active obese and nonobese patients with regard to the mean Harris hip score (91 versus 94 points, p = 0.091), the mean Western Ontario and McMaster Universities Osteoarthritis Index (16 versus 11 points, p = 0.135) or the mean UCLA activity scores (8.7 versus 8.8 points, p = 0.400). No hip in either group had thigh pain or a revision or ceramic fracture.

Conclusions: The most striking findings in this study were the equivalent results achieved in highly active obese and nonobese patients undergoing primary cementless total hip arthroplasty using an ultrashort metaphyseal-fitting anatomic cementless femoral component.