The effect of autologous bone block and bioabsorbable screw in enlargement of bone tunnel in reconstruction of anterior cruciate ligament

PURPOSE: After reconstruction of Anterior Cruciate Ligament (ACL), enlargement of bone tunnel is affected in different rates depending on graft fixation techniques. In this work, we searched the difference of tunnel enlargement between tibial fixation using autologous tibia bone block and tibial fixation using bioscrew. METHOD: In this prospective work, 48 patients are taken assessment, who were operated because of ACL rupture, from January 2012 to October 2013. The patients are operated by one surgeon and Hamstring tendon is used as graft (semitendinosus folded twice and gracilic tendons). Tibial fixation of 22 patients is ensured by autologous bone block and spiked washers. Tibial fixation of 26 patients is ensured by absorbable bioscrew and “U” nail. In both patient groups, femoral determination is made using sling implant. Between 2 and 2,5 postoperative years, the patients, visualized using computarized tomography, are assessed in enlargement of tibial tunnel diameter. Under clinical circumstances, patients are assessed using Lachman Test and Tegner Activity Score. RESULTS: Sagittal and coronal Computarized Tomography vision of 48 patients, tunnel diameters are measured from 2 cm distal of articular surface, then the percentage of bone enlargement is counted. The tunnel diameter enlargement of 22 patients, to whom autologous bone block is used is %-0,18 in average, but the enlargement of 26 patients, to whom bioabsorbable screw is used, is 9,98 in average. When we compare the two group of tests, it is found that this test is statistically senseful in enlargement of tunnel diameter(p<0,001). When we compare the patients, the enlargement of tunnel gets lesser when we use bone block. According to Lachman test and Tegner Activity Score, it is not found any meaningful difference between two groups. CONCLUSIONS: After two years, in comparison with the patients used bioabsorbable screw, the patients, used autologous bone block, encountered lesser bone loss. This method gives a couple of benefits; lesser bone loss lesser enlargement of tunnel diameter, easier surgery revision(although there is no difference clinically), furthermore, it makes the surgery easier because it eliminates one stage of the operation. Besides, the usage of autologous bone block provides meaningful decrease in costs and this is an important advantage.