Knee Arthrofibrosis: A Pain-Free, Stepwise Approach to Regaining Motion

Written by Dan Vassilaros, Ph.D. | Feb 9, 2026 6:55:51 PM

This is the first post in a short series about how people with arthrofibrosis of the knee can use OrthoBike at home and in the clinics to regain mobility they were told they would likely not see again.

I invite you to suspend your well-earned skepticism as you read and think about these posts.

What is Arthrofibrosis of the Knee?

Arthrofibrosis–nobody knows this word unless their body has ambushed them with excess scar tissue after knee surgery or injury. Arthrofibrosis of the knee occurs when excessive scar tissue forms inside the joint, limiting motion and making normal rehabilitation impossible.

You who are reading this post already know by hard experience more about this awful topic than I [hope I] ever will.

Arthrofibrosis does not improve with standard of care stretching, strengthening, and time.

When scar tissue becomes dense and organized inside the joint, forceful stretching and aggressive therapy often make things worse, not better. Progress stalls and patients may be looking at more surgery or an MUA.

Why Knee Arthrofibrosis Patients Should Have Hope

I accept that this could be a difficult statement. But I have learned from 13 years of working with knee patients using the OrthoBike that there is another non-surgical option.

How can I make this claim? Because:

  1. I know people who resolved their severe cases of knee arthrofibrosis at home under their own control, without pain, incrementally and systematically, over time.
  2. I know how they did it: incremental pedaling therapy with OrthoBike.

That would have been impossible if OrthoBike were just another recumbent stationary bike.  

How OrthoBike Changes the Game for Arthrofibrosis Rehab

OrthoBike’s patented design truly changes the game for people dealing with knee arthrofibrosis, and it does so in a very specific way.

 

Its design gives you two things that are essential for recovery: complete control over your knee’s range of motion, and a clear, stepwise path to improving that motion over time. Every adjustment is mechanical, repeatable, and under your control.

By adjusting the pedal crank length and the seat position together, you can set a precise limit on how much your knee bends while pedaling, then advance that limit gradually as your knee adapts.

  • Pedal cranks adjust from a very short 2” to a long 6”.
  • Each combination of seat and pedal settings determines maximum pedaling flexion.
  • Knee flexion ranges from about 55° to > 110°.
  • Knee flexion progresses stepwise in increments of 5°, 4°, and 3°, depending on the length of the pedal cranks.
  • You can start pedaling therapy at your pain-free flexion range.

OrthoBike gives you the opportunity to get the great benefits of cycling therapy, starting where your knee flexion is today and progressing only when you are ready. Pain-free. Under your control. At home.

The Stepwise Knee Flexion Recovery

Arthrofibrosis recovery with OrthoBike happens in a stepwise progression where knee flexion increases in small, controlled increments over time.

This graph illustrates the idealized progression arthrofibrosis patients experience. Patients can start near the bottom left, around 60° of flexion. They see progress happen by:

  1. accumulating thousands of pain-free revolutions at a fixed flexion angle;
  2. making a small adjustment to the pedal crank or seat position to add a small increment of angle to the maximum flexion; and
  3. repeating the process.

Each “step” up and to the right in the graph represents a measurable increase in knee mobility. These are hard and fast mechanical settings based on clinical research.

What this graph really shows is how OrthoBike cycling therapy permanently elongates your knee’s soft tissues, one step at a time.

The best part is that you have control of your rehab. You get to decide:

  • how long you stay at each step - maybe 5,000 revolutions, maybe 20,000;
  • when you’re ready to progress - push against tightness but never pain;
  • how fast or slow the process unfolds - at least two rides a day, more if you choose;

Two Keys to Successful Arthrofibrosis Rehab

More than 30,000 knee patients have ridden OrthoBike over thirteen years. I learned two key principles from the knee patients who suffered from severe arthrofibrosis.

Principle 1: Incremental progress requires patience

Arthrofibrotic knees can be healed incrementally. A little daily effort, over time, yields great changes.

You have to be committed to 2-4 months of daily riding therapy. This is not an easy, slam-dunk solution. Remember, you will be 2-4 months older whether you treat your knee with OrthoBike or not.

Be patient, stay the course.

Be like Julius Caesar, when he was allegedly asked about his arthrofibrotic knee rehab with OrthoBike: vene, vidi, perseveravi, vici.

Principle 2: Positive feedback keeps you pedaling

OrthoBike gives you unmistakable positive feedback every time you push the seat closer or lengthen the pedals. It means your knee is gaining mobility. And you can see it for yourself.

This feedback gives you hope.

How you feel when you gain that first 10° of absolute flexion improvement will amaze you and be so gratifying.

Your resolve to continue riding will be strengthened.

You won’t need someone to measure your knee flexion and report that you are making progress. You will already know - because you have been changing your seat and pedal settings as your knee gained more and more mobility. Simple.

OrthoBike makes cycling therapy possible

OrthoBike changes the game for patients suffering from knee arthrofibrosis. It gives you the opportunity to get cycling therapy for your knee if it won’t bend enough to ride a conventional stationary bike.

This is an option you did not have before OrthoBike.

Contact us to learn more about OrthoBike HERO or to reserve one for home use →

Click here for a technical review of the science behind OrthoBike.