[The MacIntosh extra-articular knee stabilisation procedure -- an alternative after failed ACL reconstruction?]

Chronic knee instability after loss of the ACL and failed ACL reconstruction is a great problem for the patient and a complex treatment challenge. Minimizing the feeling of instability is the most important issue for the patient. In case of lack of autologous material for reconstruction and lesions of the knee joint because of performed intra-articular procedures, extra-articular techniques are an alternative. In the modified MacIntosh procedure, we tie a strip of iliotibial tractus around the LCL and attach it to the ventrolateral tibial head by screw. Postoperatively, we begin physiotherapy under full weight bearing. Range of motion is limited to 0/0/90 degrees for six weeks. Between 1996 and 2000, nine patients who underwent surgery using the modified Macintosh technique, were evaluated prospectively. The mean follow-up was 11.4 months (6-36 months). We evaluated changes concerning pivot-shift and Lachman-test and documented Lysholm- and Tegner-activity-score pre- and postoperatively. We also registered sporting ability. The pivot shift remained positive, while the anterior drawer, documented by Lachman-test, could be reduced surgically. Lysholm- and Tegner-scores improved significantly. Preoperatively, the mean Tegner-score was 1.44 (0-3), mean Lysholm-score 55.55 points (14-88), respectively. At follow-up examination, scores had improved to 3.55 (3-4) and 82.44 points (69-95), respectively, resulting in a p-value of .007 for the Tegner-, and p = 0.008 for the Lysholm-score. Our surgical treatment could reduce the subjective feeling of instability in all cases. All patients could participate in sports activities at time of follow-up. Our results show, that extra-articular surgical procedures are adequate alternative methods of treatment in cases of persistent knee instability after recurrent failure of ACL reconstruction. The modified MacIntosh procedure described in this study shows encouraging results at medium-term follow-up. The technique is easy to perform and less traumatising for the knee joint.