Arthrofibrosis after Knee Replacement – Frequently Asked Questions (FAQ):
Arthrofibrosis after knee replacement involves formation of excessive scar tissue in the knee joint after knee replacement that leads to stiffness (inability to fully extend and/or flex) in the knee.
Bringing the knee straight is called knee extension. Normally, the knee can be brought to full extension or even slightly past full extension. Flexion contracture means inability to bring the knee to full extension. This is expressed in degrees. For example 10 degrees of flexion contracture means the knee is lacking 10 degrees from full extension.
Bending the knee is called knee flexion. Normally, the knee can be flexed until the back of the calf touches the back of the thigh. Range of flexion indicates how far the knee can be flexed. This is expressed in degrees. For example 100 degrees of range of flexion means the knee is able to bend to 100 degrees from full extension. This is measured from full extension (0 degrees) irrespective of whether the patient has flexion contracture or not.
Range of motion indicates the knee extension and knee flexion values. For example, if a knee has 10 degrees of flexion contracture and 100 degrees of range of flexion, the range of motion is 10 – 100 degrees.
Arc of motion indicates the motion possible between maximum knee extension and maximum knee flexion. For example, if a knee has 10 degrees of flexion contracture and 100 degrees of range of flexion, the arc of motion is 90 degrees (100 minus 10).
What is the difference between flexion contracture and “quadriceps lag (extensor lag) or extension lag”?
In both, the patient is unable to fully straighten the knee voluntarily (active extension). The knee can not be brought fully straight passively by the examiner (passive extension) in flexion contracture but the knee can be brought fully straight passively by the examiner (passive extension) in quadriceps lag.
Some amount of scarring is part of the normal healing process after knee replacement and it does not cause symptoms. In arthrofibrosis, the scarring is excessive and cause symptoms.
The causes of knee stiffness after knee replacement are numerous. Arthrofibrosis is one of them.
The patient should consult an orthopedic surgeon for a thorough examination of the knee to differentiate between arthrofibrosis and stiffness from stiffness from other causes.
What are the standard treatment approaches available for arthrofibrosis after knee replacement?
The standard treatment approaches available are physical therapy, manipulation under anesthesia, arthroscopic lysis of adhesions, open lysis of adhesions and revision knee replacement.
What are the other treatment approaches available for arthrofibrosis after knee replacement?
There are many pharmaceutical and biological agents that are in the developmental stage. Also, patients have tried different treatment approaches. The reported results of these approaches are very variable and we do not have enough published medical literature evidence to recommend them as a standard treatment.
An “orthopedic sports medicine fellowship trained orthopedic surgeon” experienced in arthrofibrosis after knee replacement should preferably perform arthroscopic lysis of adhesions for arthrofibrosis after knee replacement.
An “orthopedic joint replacement fellowship trained orthopedic surgeon” experienced in arthrofibrosis after knee replacement should preferably perform revision knee replacement for arthrofibrosis after knee replacement. This fellowship training is variously named as Adult Reconstruction Fellowship, Hip and Knee Reconstruction Fellowship, Arthroplasty Fellowship and Total Joint Replacement Fellowship.