by PJ Ewing

We define ‘good flexion’ as a minimum of 110º bend. A lack of full knee flexion is a problem that can linger forever after a knee surgery if not solved somewhat quickly after surgery. Watch this short video to get a handle on what we’re talking about with range of motion, and why flexion/bending is a crucial part of knee surgery recovery:

We care about flexion because it greatly impacts our overall mobility and activity levels. Mobility is crucial to our overall well being. John McKay (RN) writes in great detail about how important mobility is in his article:  Want to Live Longer, You May Want to Start from the Ground Up.

You need good flexion to do basic things like walk up stairs, enter/exit a vehicle, play sports, garden, kneel down to play with your grandkids. Here are some benchmarks:

If you do not get “good flexion” what are the implications?

There is a decline in muscle strength and other factors as we age. Being mobile helps put off the impact of those conditions.

For those facing surgery, your pre-surgery flexion is predictive of your post-surgery flexion as demonstrated in this research by Natarajan, Narayan, and Vijayaraghavan.

In the study it is shown that “pre-operative flexion significantly influenced the post-operative flexion”. Pre-operative flexion “is a good parameter for predicting the post-operative outcome.” 2

“There was a positive correlation between pre-operative and postoperative flexion; the better the pre-operative flexion, the better the post-operative flexion. However, good flexors tend to lose flexion while the poor flexors tend to gain some. TKR can produce a predictable result, not totally dictated by poor pre-operative flexion. Interestingly, restoration or even improvement in ROM for those with good pre-operative flexion may be limited by implant design and soft tissue tension.”

Just think about that for a second. “Good flexors tend to lose some and poor flexors tend to gain some,” meaning that even if you have good bending before surgery you might lose ground. And if you have poor flexion before surgery there is an opportunity for gains. With a knee replacement surgery, it is not simply the new mechanical joint that can be the determining factor. Rather, it is the ligaments, tendons and muscles that you have had all your life that may impact how well you can flex your knee.

And just for the record this is news for all of us as the study points out: “Other factors such as age, sex, etiology, type and kind of prosthesis did not show much evidence in influencing the outcome on postoperative ROM at the end of one year follow up interval.”

That said, the question becomes which pre-hab program should you go through? For a definitive comparison between a rigorous eight week “boot camp” pre-hab program, and a short prehab program using the X10, listen to this interview with Dr. Carl Freeman. Or just know that you can get more done in 10 days on the X10 than eight weeks of hard core pre-hab using conventional methods.

To read research about pre-hab before knee surgery click here: The Value of Pre-hab Before Knee Sugery

To hear patient accounts about their pre-hab see below:

First look at this quick guide to knee flexion/bending:

Now let’s explore your options depending on where you fit into one of these categories.

If your flexion is ‘very poor’ (<80º) you may need a procedure like MUA/Arthroscopy or even TKA. See a surgeon to discuss your options. If you have already had a surgery there is the option to consider using the X10 to help your ability to bend your knee.

Frank had poor flexion two years post surgery and was still able to fix the problem. You can watch Frank speak about his recovery here: Frank’s Story.

If your flexion is ‘poor’ (80º – 95º)

If your flexion is a concern but ‘manageable’ (96º – 109º)

Nan struggled after her total knee replacement for many months until she finally got to her goal. You can read (and listen to an interview of) her story here: Nan’s Story

For those with flexion over 110º

For more on how to use a stationary bike to help with flexion click here: Using a Stationary Bike After Surgery. An alternative to stationary bike is using a rocking chair which can help you work from 90º to 100º. Another technique is to sit on a dining room table (or better yet a massage table), wrap a TheraBand around your ankle and gently pull back to the point of tension, but not pain. Do this as often as you can for increments of 10 seconds.

Flexion is the number one challenge for most patients after any knee surgery including ACL, MCL, PCL, LCL, Patellar Fracture and Total Knee Replacement. A lack of full knee flexion is the number one reason patients call us six weeks after surgery looking for an “X10 Intervention”

Suffice it to say about knee flexion: “If you don’t got it, you want it. If you got it, keep it!”

This is Part Four of a series of articles on threats to a proper knee surgery recovery. I encourage you to explore the other articles in the series which you can find by clicking on the links below.

This is a free 15-part email series that runs for 30 days. We give you a broad perspective on all aspects of knee health. And we are highly prescriptive on what you can do right now to solve a tough knee recovery. We explore surgery and recovery and such subjects as ‘Lack of Full Knee Flexion’.

Executive Editor: PJ Ewing ([email protected])