Total Knee Arthroplasty (TKA - AKA getting a knee replacement) is a commonly performed orthopedic surgery. People choose to undergo this surgery most commonly to alleviate pain and improve function after severe osteoarthritic changes to the joint.
Obviously any surgery is a little nerve racking and people have questions about what the expected outcomes can be and what they can do to help ensure the success of the surgery so that their return to the activities they love is achieved. Of course each and every case is unique, and there are a number of determinants of what makes the most successful outcomes.
Researchers have done analysis to determine which physical qualities are important for good outcomes after surgery. I’ve discussed some of the more important ones below, but really what the research says is that the stronger and more mobile you are going into surgery, the faster and more robust your recovery will be. Fit in equals fit out, makes sense right? Let’s discuss a key few qualities:
Quadriceps strength - Strength of the quadriceps muscle (the front of the thigh) has been shown to be highly correlated with successful return to function, more so than range of motion or even low pain levels! Weakness of the quads is a key impairment for many patients going into surgery so it stands to reason and research that strength here would be a key determinant of successful recovery.
It is clear that working on quadriceps strength post operation is important, but is it possible to get a jump on things by starting strength training beforehand? So far the research has not shown that strength training before surgery leads to improved outcomes, so I don’t look at it as a “must do”. However it certainly doesn’t hurt anything to maximise your strength going into surgery and I support individuals who want to get a jump on training habits early.
Gluteal strength - This is an interesting measure to look at because the gluteal muscles act at the hip, not the knee right? Well, not exactly… think of the hip, knee and ankle not as being individual, separate and independent “bits”, but rather as parts in a whole lower extremity that functions as a unit! To test this idea for yourself, try doing a charleston dance. You may remember this one, it’s the wonky chicken dance that we all (or me at least) had an 11 year old fascination with (check out a great demo here https://www.youtube.com/watch?v=xfAMIrUao9w). Notice how large a change in position at the knee and ankle is created by a relatively modest hip abduction/adduction and rotation movement.
So strength and stability at the hip is crucial for stability at the knee (and points south) as well. Research has shown that strength at the glutes is helpful for functional performance in people after TKA so strengthening here is a great way to ensure a maximal recovery afterward.
Walking and use of mobility aides before surgery - Put simply, those who can walk further and with less use of mobility aides (walker and cane) do better coming out of surgery. Obviously mobility aides exist for a reason (to help stabilise your walk) and are absolutely needed for many people. Still, practicing independent walking as much as your body can safely tolerate going into surgery may have a positive effect on the height to which you bounce back post op. If you are uncertain about this a discussion with a physiotherapist will help you to determine the best approach for your specific situation.
Recommended sporting activities after TKA: Common sense rules the day when it comes to choosing physical activities after you have recovered from the knee replacement surgery. Participate occasionally and with caution in sports which demand high joint loads, such as skiing, tennis, and hiking. There are still lots of great activities like walking, swimming and (believe it or not) ballroom dancing that you can train worry free in! Have a discussion with your physiotherapist for recommendations specific to your case.
Remember that no matter how strong, stable and fast you are going into surgery, the first month afterward doesn’t feel too good, and function pretty much stinks. In fact, it isn’t until the third month post surgery that patients begin to report levels of physical function above where they were beforehand. As with all rehabilitations, recovery post TKA is a process that requires patience, vision, discipline and consistency. As I love to say; the process of successful rehabilitation demands the same habits as success anywhere in life and can be a great avenue for personal development. Enjoy it!
If you have any questions about knee replacement rehab or any other physiotherapy related questions don’t hesitate to ask me, I will respond! I look forward to hearing from you.
Further reading on this topic
Mizner, R. L., Petterson, S. C., & Snyder-Mackler, L. (2005). Quadriceps strength and the time course of functional recovery after total knee arthroplasty. Journal of Orthopaedic & Sports Physical Therapy, 35(7), 424-436.
Jones, C. A., Voaklander, D. C., & Suarez-Almazor, M. E. (2003). Determinants of function after total knee arthroplasty. Physical therapy, 83(8), 696-706.
Piva, S. R., Teixeira, P. E., Almeida, G. J., Gil, A. B., DiGioia, A. M., Levison, T. J., & Fitzgerald, G. K. (2011). Contribution of hip abductor strength to physical function in patients with total knee arthroplasty. Physical therapy, 91(2), 225-233.
Petterson, S. C., Mizner, R. L., Stevens, J. E., Raisis, L., Bodenstab, A., Newcomb, W., & Snyder‐Mackler, L. (2009). Improved function from progressive strengthening interventions after total knee arthroplasty: a randomized clinical trial with an imbedded prospective cohort. Arthritis Care & Research, 61(2), 174-183.
Meier, W., Mizner, R., Marcus, R., Dibble, L., Peters, C., & Lastayo, P. C. (2008). Total knee arthroplasty: muscle impairments, functional limitations, and recommended rehabilitation approaches. journal of orthopaedic & sports physical therapy, 38(5), 246-256.