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.
Flexed knee gait – A patient who walks with a flexed knee gait should be assessed to determine if the quadriceps are inhibited or weak, or if there is a mechanical block to extension.
Worsening pain – Pain is a normal feature of injury and surgery, but usually settles in a predictable manner. When pain does not settle or becomes worse, arthrofibrosis must be excluded. Characteristically, pain may also be triggered by quadriceps contractions and tenderness to palpation around the patella and patellar tendon.
It is important, when pain is severe, to keep in mind the disorder of complex regional pain syndrome which may need to be excluded.
Weak, wasted quadriceps – An inability to voluntarily perform a strong quadriceps contraction in the initial 1-2 weeks following knee trauma or surgery. No tension in the patellar tendon. Patella fails to move upwards when the quadriceps contract.
Warm joint – It is normal for the knee to be warm during the acute inflammatory stage after injury or surgey. This usually settles within 2 weeks. If the joint remains warm at this time, or any increase in warmth is suddenly experienced, the possibility of infection exists and the clinician should respond appropriately.
Continued tissue swelling – Tissue swelling in arthrofibrosis has a particular characteristic, making it relatively easy for the alert clinician to distinguish this from an effusion (fluid in the joint space) or haemarthrosis (blood in the joint space).
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.