An evaluation of proximal femur bone density in young, active patients undergoing total hip arthroplasty at one year postoperatively. Issue 1 (January 2019)

• Record Type: Journal Article
• Authors: Nam, Denis; Salih, Rondek; Barrack, Robert L; Nunley, Ryan M
• Is Part Of: Hip international. Volume 29:Issue 1(2019)
• Page Start: 51
• Page End: 57
• Publication Date: 2019-01
• Subjects: Activity level -- bone density -- periprosthetic -- stem design -- total hip arthroplasty; Hip joint -- Pathophysiology -- Periodicals; Hip joint -- Diseases -- Periodicals; Hip joint -- Surgery -- Periodicals; 617.581005
• DOI: 10.1177/1120700018761152
• Languages: English
• ISSNs: 1120-7000

Abstract

Background: Prior investigations have shown a decrease in periprosthetic bone mineral density (BMD) of the calcar following total hip arthroplasty (THA). The purpose of this investigation was to study proximal femur BMD in a cohort of young, active patients following THA at 1 year postoperatively using a recently introduced stem design. Methods: This was a prospective, IRB-approved investigation of patients with an age <65 years, BMI <35 kg/m 2, and presymptomatic UCLA score of> 6 undergoing a primary THA for a diagnosis of osteoarthritis. All patients received a titanium, proximally coated, tapered cementless femoral stem (ACCOLADE II, Stryker Inc, Mahwah, NJ, USA). Dual energy X-ray absorptiometry scans were performed at 6 weeks, 6 months, and 1 year postoperatively. Bone density was analyzed for 7 traditional Gruen zones with BMD ratios calculated for change in BMD compared with the baseline. Results: 31 patients (mean age of 52.6+ 6.5 years, BMI of 27.9+ 3.9 kg/m 2, and UCLA activity score of 7.3+ 1.9) were included. The mean BMD ratio decreased at the 6 months and 1 year interval in zones 1 and 2. However, the mean BMD ratio was maintained in Gruen zones 3 thru 7 with zone 7 (medial calcar) demonstrating 100% maintenance of the baseline BMD at 1 year. Conclusion: This study demonstrates the maintenance of medial calcar bone density at 1 year postoperatively in young, active patients undergoing THA. Further longitudinal analysis of this stem design is necessary to elucidate the significance of this finding.