Arthrofibrosis following ACL reconstruction - reasons and outcome

Introduction: Arthrofibrosis is a complication that severely influences the clinical outcome after anterior cruciate ligament (ACL) reconstruction. This retrospective clinical study analyses risk factors and outcome after arthrolysis in a large population. Material and methods: Two hundred twenty-three patients who had undergone arthrolysis after ACL reconstruction were examined. Range of motion (ROM) was reduced due to arthrofibrosis of the joint in 70% (n=156). Other reasons, such as cyclops syndrome or osteoarthritis were found in 30% (n=67). The mean time interval between arthrolysis and follow-up was 4.29 years. We recorded timing of surgery, additional injuries, state of the knee before reconstruction, range of motion, pain during rehabilitation, beginning, duration and type of rehabilitation, severity and etiology of joint stiffness and the time between ACL reconstruction and revision. The present state of the knee was documented using the IKDC form. Results: A significant correlation of arthrofibrosis and preoperative irritation (p<0.001), preoperative limited ROM (p=0.001), perioperative pain (p=0.046) and early beginning of muscle training (p=0.064) was found. Combination of a remaining loss of extension and development of degenerative joint disease was also significant (p=0.001). The decrease of sports activity compared with the level before ACL injury was highly significant (p<0,001). The criteria to minimize the risk of arthrofibrosis and the optimal timing of arthrolysis are pointed out.