Arthrofibrosis (from Greek: arthro- joint, fibr- fibrous and -osis abnormality) is a complication of injury or trauma where an excessive scar tissue response leads to painful restriction of joint motion, with scar tissue forming within the joint and surrounding soft tissue spaces and persisting despite rehabilitation exercises and stretches. Scarring adhesions has been described in most major joints, including knees, shoulders, hips, ankles, and wrists as well as spinal vertebrae.
Arthrofibrosis of the knee
Arthrofibrosis of the knee has been one of the more studied joints as a result of its frequency of occurrence. Beyond origins such as knee injury and trauma, arthrofibrosis of the knee has been associated with degenerative arthritis. Scar tissues can cause structures of the knee to become contracted, restricting normal motion. Depending on the site of scarring, knee cap mobility and/or joint range of motion (i.e. flexion, extension, or both) may be affected. Symptoms experienced as a result of arthrofibrosis of the knee include stiffness, pain, limping, heat, swelling, crepitus, and/or weakness. Clinical diagnosis may also include the use of magnetic resonance imaging (or MRI) to visualize the knee compartments affected.
The consequent pain may lead to the cascade of quadriceps weakness, patellar tendon adaptive shortening and scarring in the tissues around the knee cap—with an end stage of permanent patella infera—where the knee cap is pulled down into an abnormal position where it becomes vulnerable to joint surface damage.
Patients who are recognized as developing arthrofibrosis may improve motion with appropriately directed physical therapy, corticosteroid injections, non-steroidal anti-inflammatory drugs, and cryotherapy. In many instances, however, as fibrosis has set in, surgical intervention is necessary. Specialized arthroscopic lysis of adhesions knee procedures such as anterior interval releases may be indicated and utilized to great success, in the hands of an appropriately trained specialist.