[Reconstruction of the anterior cruciate ligament: comparison of patellar bone-tendon-bone and hamstring tendon graft methods. Part 2. Short-term evaluation of the hamstring tendon graft technique with use of the Rigidfix system].

PURPOSE OF THE STUDY

The high number of patients with femoropatellar complaints following ACL reconstruction with bone-tendon-bone (B-T-B) autograft led us to use and subsequently evaluate hamstring tendon grafts fixed with the Rigidfix system. In this study we present the evaluation of short-term results.

MATERIAL

We evaluated 85 patients (51 male and 34 female) at an average follow-up of 14 months. The average age of the group was 29.7 years (range, 16 to 59 years). In 46 patients we treated the right knee and in 39 patients the left knee. Fifty-five patients in this group also had an associated injury to the soft knee tissues. For reconstruction, a semitendinosus tendon graft was used in 56 knees and a semitendinosus-gracilis tendon graft in 29 patients.

METHODS

The operation was carried out with tourniquet application to the extremity in a flexed position. The tendon of the semitendinosus muscle was harvested through an oblique incision and, in some cases, when its width and length was not sufficient for graft construction, the gracilis muscle tendon was harvested too. The graft, at least 75 mm by 8 mm in size, was prepared on a graft board. After having drilled the both tunnels, the femoral Rigidfix reamer was inserted in a routine manner and protective sleeves for Rigidfix cross pins were introduced. With the extremity in semiflexion, the inserted graft was fixed to the cortical bone by absorbable cross pins on the femur and absorbable interference screws on the tibia. The postoperative treatment involved procedures as in the B-T-B technique.

RESULTS

The group was evaluated by the Lysholm score system, with an average of 84.3 scores achieved. The men showed better outcomes than women, i. e., 85.7 and 81.4, respectively. The scores in the patients with a single tendon did not differ significantly from the patients with a combined tendon (semitendinosus, 83.2 vs. semitendinosus-gracilis, 84.2), nor did they greatly differ between the patients with injury to ACL alone and those with ACL and associated soft tissue injuries (ACL, 83.9 vs. ACL+ associated injury, 85.5). Most of the patients (94 %) were satisfied with the outcome of treatment. The complications involved thrombosis of the operated lower extremity in three patients and repeat surgery for hematoma in two patients. Knee instability was found in five patients. One graft failed to restructure and incorporate, in two knee tunnels were incorrectly centered and two grafts ruptured due to trauma. Three of these patients underwent repeat surgery.

DISCUSSION

Our results, as evaluated by the Lysholm score system, were in agreement with those of other authors. We did not find any difference in knee stability between the patients treated by the hamstring tendon technique and those undergoing reconstruction with a patellar B-T-B autograft. However, the patients with hamstring tendon reconstruction reported a considerably lower number of femoropatellar problems.

CONCLUSIONS

ACL reconstruction with a hamstring tendon autograft fixed with the Rigidfix system is a suitable alternative technique to ACL reconstruction carried out with a patellar B-T-B graft. It provides equal knee stability but has significantly lower donor site morbidity. It is suitable for patients who have contraindications for the B-T-B technique and in persons practicing little or no sports.