WOLFEBORO — Total knee arthroplasty (TKA), or a total knee replacement has become a commonly practiced surgical procedure. The procedure of “replacing” one’s knee involves the removal of the knee joint and replacing it with a mechanical component. People often venture down the path of surgical contemplation when their knee symptoms have become so severe, that day-to-day function becomes drastically limited. If one is indeed a candidate for the surgery, physical therapy (PT) has the potential to offer a host of benefits for the patient and their new knee.

Odds are that you know someone who has had their knee replaced or have first-hand experience with this surgical procedure. according to the National Center for Health Statistics, over 500,000 total knee arthroplasties were done last year in the United States. At this frequency rate, orthopaedic surgeons literally have the procedure down to a science.

For all intents and purposes, the knee replacement is just as it sounds — a replacement of the knee joint. more specifically, parts of the two main weight bearing bones which make up the knee joint are removed and replaced with a metal component, which is often titanium. These bones are the lower end of the femur bone (the long thigh bone) and upper end of the tibia bone (shin bone). These two bones articulate with one another and allow for normal function of the knee. this function can become compromised however, when degenerative conditions such as osteoarthritis (OA), wear away the cartilage linings of the joint resulting in pain and reduced mobility.

After you have had a knee replacement, there is some work that goes into the recovery to allow for a more productive return to function. Metaphorically speaking, it is not quite as simple as driving off in your car after you have had your brakes replaced. After going through the procedure, there is a loss of strength and range of motion (ROM) that is common after a knee replacement. The soreness from the surgery and the post-operative swelling can limit the ability of your muscles to contract and the ability to bend and straighten the knee is often compromised. this can make such routine tasks as transferring in/out of a chair and walking quite daunting tasks. Rehab can help bridge the gap between such a status and a return to mobility. to address strength deficits, physical therapists will use an array of therapeutic exercises to help regain strength and rebuild muscle. Neuromuscular stimulation devices are also used to facilitate muscle contraction with the strengthening process.

Long term studies have demonstrated that a return of strength in the leg muscles following a TKA is one of the biggest determinants of being able to function appropriately. more specifically, strengthening of the quadriceps muscles is key to allow for the execution of every day activities and hobbies. The quadriceps are the muscle group on the front of the thigh that help to straighten the knee and flex the hip. One need not be an Olympian weight lifter to reap the benefits of strengthening. Both high and low level resistance training appear to be equally as effective at promoting strength and allow for better function.

To address ROM limitations, physical therapists pull from a bag of exercises and manual techniques specifically designed to improve ROM by addressing muscle tightness and joint restrictions. Improved knee ROM is crucial following a TKA. Tasks such as negotiating stairs, getting in/out of the car, and squatting to retrieve items from the floor all benefit from progressed ROM after surgery. Exercises targeted to improve the bend of the knee (flexion) and the straightening of the knee (extension) are often conducted. according to research, obtaining knee flexion above 120 degrees (although the more the better) tends to lead to the most optimal outcomes. as far as extension, as close to straight as possible (0 degrees extension) is equally as desirable for optimal function with walking and general function.

Other aspects of rehab involve showing someone how to move their new knee. while it may seem an inherently easy task to move a new knee, it takes some practice and re-education of the muscles to move someone from point a to B. Learning how to move the lower extremity through the different phases of the walking or gait cycle is something that is reinforced. Research has also shown that less subtle movements, such as getting out of a chair, are accomplished with an altered movement pattern after surgery. for example, patients tend to lean forward more and use more of their buttock muscles versus their thigh muscles to complete the motion. Rehab can be very successful at retraining these altered movement patterns to get out of the chair and move in a more “normal’ fashion.

While replacing the knee may not be as simple as replacing the brakes on your car, for many, the procedure is a worthwhile venture to reduce pain and allow people to more fully participate the various activities that make up life. from improving strength, to managing symptoms, to developing an exercise program, the rehab is indeed something that is quite “kneedy.” It has the potential to not only make for a more full return to function, but also to build and reinforce practices that will last for the life of the new knee.

Back Bay Rehabilitation, a department of Huggins Hospital, opened a rehab facility at Tamworth Family Medicine at 577 White Mountain Highway this summer. Ben Wiggin, MS, PT, is the physical therapist on-site. for more information, contact Back Bay Rehabilitation in Wolfeboro at 569-7565.