Arthrofibrosis After Knee Ligament Injury

Surgery to repair injuries to the knee, especially anterior cruciate ligament (ACL) tears, can lead to loss of motion in the knee called arthrofibrosis.

Too much scar tissue forms inside and around the joint. The result is painful restriction of motion. Even with daily exercise, stretches, and rehab, disabling loss of flexion, extension, or both can occur.

In this article, orthopedic and neurosurgery specialists from the Greenwich Sports and Shoulder Service in Greenwich, Connecticut provide an update on risk factors, pathology, and treatment of knee arthrofibrosis.

Patients with improper graft placement in ACL repairs are affected most often. If the graft tissue is too short or placed too far in one direction (anteromedial), loss of flexion occurs.

Some patients healing process involves the production of too much scar tissue. Tiny adhesions form between the tissues preventing full motion. Loss of motion leads to muscle weakness and atrophy. A painful limp and loss of function may also occur.

The incidence of arthrofibrosis after ACL surgery has declined over the years. Range of motion right after surgery and avoiding prolonged immobilization have helped changed this picture.

When arthrofibrosis does occur, manipulation is advised as early as possible. This is usually between four and 12 weeks of the ACL reconstruction. Anyone who does not achieve 90 degrees of flexion despite daily rehab should consider having a manipulation procedure. Delaying too long can cause further complications.

The authors review manipulation techniques using arthroscopy versus an open method. Whenever possible, the arthroscopic method is used. Arthroscopic manipulation allows the surgeon to assess all areas involved.

Loose fragments of cartilage, tissue, or debris are removed. Saline is injected into the joint to flush it out. Any tight bands of tissue can be released. The surgeon can check for graft impingement. The condition and position of the graft can also be checked and corrected if necessary. Open surgery is only done when closed surgical management has failed.

More studies are needed to assess the long-term results of manipulation for knee arthrofibrosis. Better understanding of the healing process may help prevent excessive scarring in the first place. The surgeon should watch carefully for knee arthrofibrosis in patients with high-energy and multiple ligament injuries.