The Effects of Prehabilitative Exercise on Functional Recovery Following Total Knee Arthroplasty

People with knee arthritis have lower levels of physical activity and are more susceptible to suffer from additional medical conditions of heart disease, respiratory conditions, diabetes and stroke. For patients with end stage knee osteoarthritis, total knee arthroplasty (TKA) has been widely accepted as beneficial for increased patient satisfaction and improved function. To provide high quality of care and optimize TKA outcomes, healthcare providers need to make decisions about resource allocation. The theory of Prehabilitation proposes to increase strength, balance and endurance prior to surgery with the benefit of less decline and improved rate of recovery following surgery. Preoperative quadriceps strength and walking ability have been shown to be predictive of function one year post operation. However, systematic reviews of Prehabilitation have been inconclusive and this warrants additional investigation.

Prior studies of Prehabilitation have been inadequately designed or have low levels of therapeutic validity. A prior study completed in Spain provided pre-surgical exercise three times weekly for eight weeks and provides an example of high therapeutic validity with the corresponding significant results post-operation. The objective of this study is to translate knowledge of the pre-surgical exercise program completed in Spain into the local context of a hospital system in Virginia. Due to local area considerations of equipment and time, modifications of the Spanish pre-surgical exercise program are to be tested. These adaptations will allow for implementation within American College of Sports Medicine strength training guidelines using individualized exercise progressions and completion of three clinic based sessions per week.

Subjects that provide informed consent and complete initial screening will be scheduled for two pre-surgical and two post-surgical assessment sessions. On the first assessment session, subjects will be classified into three levels adapted from prior research and input from clinicians and administration to determine the need for pre-surgical preparation. Those subjects in the two most severe levels will be asked to participate in a Prehabilitation exercise program for three times a week for eight weeks and if consent is provided, will be randomized into the control (Joint Education Home Exercise Class only) or the intervention exercise program using a gender stratified randomized sequence generated prior to subject recruitment. The researcher will notify sequential subjects of their group allocation based on the predetermined randomized sequence at the end of the first testing session.

The goal of the prehabilitative exercise is to provide an individualized exercise program to be completed 3x/week for 8 weeks. The exercise sessions will be completed in the rehabilitation office at the Institute of Orthopedics and Neurology (ION) by physical therapy students with oversight from licensed PT at no cost for each subject. Ongoing evaluation of each exercise session will use the Borg Rating of Perceived Exertion (RPE) supplemented with Heart Rate (HR) and Blood Pressure as needed to target the moderate intensity training level (40-60% HR Max) or above as appropriate to each individual. Weekly evaluation of each individual's exercise program will be completed and progressed as able. Outline of Exercise program includes:

• Warm-up (Low intensity < 40% HR Max) 5 minutes of walking or bike
• Flexibility: knee flexion/ext and hamstring stretching
• Strengthening, Balance and Functional activities (Moderate intensity 40-60% HR Max)