AB1180 THE CHANGES OVER TIME OF KNEE STRENGTH AND FUNCTIONAL OUTCOMES BEFORE AND AFTER BILATERAL TOTAL KNEE ARTHROPLASTY

Abstract

BackgroundKnee osteoarthritis is the most common joint disorder and is associated with functional disability and pain. Total knee arthroplasty (TKA) is considered as an effective treatment for patients with end-stage knee osteoarthritis. However, most patients experienced deterioration in knee strength and functional outcomes immediately after surgery.ObjectivesThe overall aim of this study was to investigate the change over time of knee strength and functional outcomes before and after bilateral total knee arthroplasty.MethodsRetrospective cohort data of 308 patients who underwent primary bilateral TKA were analyzed. Patients underwent home-based preoperative rehabilitation program (3 times per week for 3 or 4 weeks) including strengthening and resistance training. After TKA, standard rehabilitation program was applied to all patients. Outcome measures were assessed 3 times, preoperatively and at 6 weeks and 3 months after surgery which included performance-based physical function test and self-reported physical function questionnaires. Assessment were included the isometric knee extensor and flexor strength of both knees, timed up-and-go (TUG) test, timed stair climbing test (SCT), 6-minute walk test, isometric knee extensor and flexor strength of both knees, knee flexion and extension range of motion, Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) for pain, stiffness, and functional levels. The knee flexion and extension range of motion (ROM) was assessed 5 times including at the beginning and end of standard rehabilitation.ResultsThe knee extensor strength and ROM, and SCT of ascending were worsened at the 6 weeks after surgery, and these measures significantly improved following the 6 weeks. The ROM of knee flexion improved earlier than other physical functions and ROM of knee extension worsened after 6 weeks postoperatively. However, the result of self-reported physical function and other performance-based physical functions continued to improve significantly at 6 weeks and 3 months after surgery.ConclusionThis study demonstrated that the patients who underwent bilateral TKA surpassed most of their physical functions in the 3 months before surgery. However, the recovery of performance-based physical function and self-reported physical function occurred at different times after surgery. Therefore, a rehabilitation treatment strategy according to these changes of physical functions is needed.