[Arthrofibrosis]

Arthrofibrosis represents a severe complication in joints after trauma and surgery, with loss of motion due to an excessive fibrotic response in the repair process. Patients with primary arthrofibrosis suffer from a general fibrotic healing response after injury or surgery, while patients with secondary arthrofibrosis exhibit loss of motion due to a local fibrotic healing response. Nonisometric positioning of cruciate ligament grafts, notch impingement, or hardware problems may lead to secondary arthrofibrosis. In contrast, the etiology of primary arthrofibrosis is still unknown. There are alterations of the extracellular matrix with an increase of collagen type VI expression similar to other local or systemic fibrotic disorders. A chronic inflammatory process may play a crucial role in the mechanism of primary arthrofibrosis and may indicate an immune response. It may be reasonable to assume that primary arthrofibrosis is an independent disease while secondary arthrofibrosis represents a true complication in joints resulting from trauma and surgery. Secondary arthrofibrosis can commonly be managed by arthroscopic procedures. Treatment of primary arthrofibrosis should usually include resection of dense fibrotic tissue in the anterior compartment of the knee and open posterior capsulotomy to allow full extension of the knee joint.