Effect of total hip arthroplasty on cardiovascular fitness.

Thirty patients who underwent total hip arthroplasty and 18 patients with medically treated arthritis participated in this study. Both groups of patients underwent a cardiovascular fitness exercise test on entering the study and 6 months, 1 year, and 2 years later. Fitness was assessed by patient performance on a graded maximal exercise test using a bicycle ergometer and metabolic cart. In the group of total hip arthroplasty patients, significant improvements in exercise duration (P = .011), maximum workload (P = .0013), peak oxygen consumption (P = .0036), and percentage of predicted maximum oxygen uptake achieved (P = .0002) were observed during the follow-up evaluation. In the group of control patients, decreases in exercise duration (P = .0001), maximum workload (P = .0001), and workload at anaerobic threshold (P = .0108) occurred without a significant change in the other measures of cardiovascular fitness. The results indicate that resumption of routine physical activities after total hip arthroplasty is associated with a corresponding improvement in cardiovascular fitness.