Arthrofibrosis after total knee arthroplasty

Six total knee arthroplasties in five patients were revised because of persistent limited motion after the primary arthroplasty. All of the revised implants were of an appropriate size and not malpositioned. No cause of stiffness was identified other than soft tissue contracture. Four of the components were posterior cruciate retaining and two were posterior cruciate substituting. Heterotopic bone formation was observed in two knees before the revision surgery and five knees after the revision surgery. Arc of motion was increased from 36°(range, 20°-70°) before revision surgery to 86°(range, 70°-110°) after revision surgery. What triggers the proliferation of extensive scar tissue formation in patients with arthrofibrosis is not clear. Some patients may be predisposed to this condition or may have it develop as a response to the surgical trauma and postoperative rehabilitation. However, when arthrofibrosis does develop after total knee arthroplasty, some improvement in motion and pain can be achieved with revision surgery.