[Functional reconstruction of the medial collateral ligament with double-bundle allograft technique]

To discuss a new technique about reconstruction of medial collateral ligament (MCL) with double bundle allograft and to evaluate the short-term clinical efficacy.

All 53 patients who suffered from valgus instability of the knee were selected. All cases were diagnosed of MCL injury because the medial gap of the knee widened more than 5 mm compared with collateral knee by the stress X-ray, MRI displayed discontinuity of MCL and valgus stress test was positive. All patients were accepted arthroscopic evaluation through inferomedial and inferolateral arthroscopy portal incisions to ascertain whether there were intra-articular injuries. An 8 cm incision was made from 1 cm superior adductor tubercle to 5 cm proximal medial tibia joint line in a longitudinal fashion. The anterior tibia insertion was defined as 15 mm lateral from the medial tibia edge and 45 mm under the medial tibia joint line. The posterior tibia insertion was defined as 15 mm lateral from the medial tibia edge and 20 mm under the medial tibia joint line. We used 5 mm or 6 mm reamer to drill the tibia tunnel along with guide pin, and then drill the femur tunnel with 6 mm or 7 mm drill in the top of the adductor tubercle about 25 mm or 30 mm length. The allograft was pulled into the tunnel from tibia to the femur and fixed with absorbable interference screw. Patients carried out active rehabilitation program after operation. One year after the operation, IKDC score, Lysholm score were used to evaluate the clinical effect.

The IKDC score (A or B, 86.78% vs. 0), Lysholm scores (89.7 ± 3.4 vs. 51.8 ± 4.9, t = -79.724, P < 0.05) were significantly improved compared with preoperative in all patients. Medial joint widened gap decreased from (10.4 ± 2.4) mm preoperative to (2.8 ± 1.5) mm postoperative from X ray and the differences were significant (t = 41.727, P < 0.05). Among these patients, the medial joint widened gap of 46 cases were less than 3 mm, 7 cases were from 3 mm to 5 mm. The range of motion was 135.4° ± 2.5° preoperative and 132.7° ± 3.7° postoperative. The 9 patients still had medial tenderness 1 year after operation.

Application double bundle allograft technique to reconstruct MCL can significantly improve the stability of the knee and the short-term clinical efficacy was sure.