EFFECT OF TOTAL HIP-ARTHROPLASTY ON CARDIOVASCULAR FITNESS

Thirty patients who underwent total hip arthroplasty and 18 patients w ith medically treated arthritis participated in this study. Both group s of patients underwent a cardiovascular fitness exercise test on ente ring the study and 6 months, 1 year, and 2 years later. Fitness was as sessed by patient performance on a graded maximal exercise test using a bicycle ergometer and metabolic cart. In the group of total hip arth roplasty patients, significant improvements in exercise duration (P = .011), maximum workload (P = .0013), peak oxygen consumption (P = .003 6), and percentage of predicted maximum oxygen uptake achieved (P = .0 002) were observed during the follow-up evaluation. In the group of co ntrol patients, decreases in exercise duration (P = .0001, maximum wor kload (P = .0001), and workload at anaerobic threshold (P = .0108) occ urred without a significant change in the other measures of cardiovasc ular fitness. The results indicate that resumption of routine physical activities after total hip arthroplasty is associated with a correspo nding improvement in cardiovascular fitness.