My Total Knee Replacement Rehab (part two)
By Robert Forster
Last month in this newsletter I recounted the decades old injury that put me on a path to total knee replacement surgery some 50 years later (read part one here)
As I was being prepped for surgery on September 27, 2024 for a total knee replacement, my resting heart rate was 51. Subsequently, on December 20 when I was being prepped for a “closed manipulation under anesthesia” some 3 months after the replacement surgery, my resting heart rate was 61.
In these statements one could easily deduct two things. First, In the 12 post operative weeks I had failed to gain the acceptable range of motion and thus the need for a closed manipulation to force the knee to bend.
Second, in spite of water based exercise workouts and stationery cycling as part of my rehab program, my metabolic fitness had deteriorated in those 3 months to the point that my heart had to work 10 beats harder per minute to meet my body’s metabolic needs at rest.
Before surgery I was meeting the requisite 5 hours of elevated heart rate activity per week. An exercise threshold that research has shown to achieve metabolic efficiency and help avoid many of the deadly lifestyle diseases (coronary atherosclerosis, stroke, diabetes, metabolic syndrome, chronic obstructive pulmonary disease and some 13 types of cancer). After a few weeks without meeting this 5 hour threshold, my metabolic fitness began to deteriorate. I also lost muscle mass as my body weight dropped 10 lbs.
What is a closed manipulation and why did I need it?
During a closed manipulation the surgeon puts the patient to sleep with anesthesia and in an attempt to gain more range of motion they then forcefully bend the knee until the aberrant scar tissue releases.
After knee surgery the first goals we have for our patients is be able to completely straighten the knee ( known as full extension ) and bend the knee ( known as flexion ) to a minimum of 120 degrees.
Being able to fully extend the knee is critical because when the knee is perfectly straight very little muscular activation is needed to keep us upright. If the knee is unable to achieve full extension, and is chronically bent, even slightly, the quadricep muscle group in the front of our thigh is constantly engaged in preventing the knee from give way and us collapsing under our body weight. This can cause muscle and tendon strain at the knee and overly fatigue the quad, hamstring and calf muscles.
At 120 degrees of flexion the knee can bend enough to comfortably put on a sock and shoe, also to reach the next step when walking up stairs and sit comfortable in tight spaces like in the car or on a plane.
In our clinic most total joint replacement patients achieve fully functional range of motion within three weeks post op. They attain pre-surgical strength and fitness within 3 months and most return to sports like cycling, tennis and skiing by the 4th month.
On national average, 4-7% of total knee replacement patients do not achieve adequate range of motion and require a closed manipulation procedure. In our clinic it’s a much smaller percentage. For me, an inflamed bursa above my knee cap was a post surgical complication that prevented me from attaining the requisite knee bend range of motion . My staff and I worked daily with every rehab technique in our collective war chest to calm down this inflammation and increase knee bend past 110 degrees, to no avail. The irony of this happening to me is not lost on me.
Since the closed manipulation I have gained additional range of motion and have made progress in regaining my fitness. Last week I progressed my cycling back to the pre-surgical level of 5 hours per week and my strength and muscle size are coming back too. All told, the surgery was a success and while I suffered some very uncommon post surgical complications, I can now see light at the end of the tunnel. As reported by our joint replacement patients, I too am glad I had it done and look forward to an another decade or two of pain free fitness training and fun!