Functional Outcome of Anterior Cruciate Ligament Reconstruction by Tibial Attachment Preserving versus Sacrificing Hamstring Graft Technique- A Prospective Interventional Study

Introduction: Anterior Cruciate Ligament (ACL) is a stout, short intra-articular, extra synovial structure. For a knee with the deficiency of ACL, the ligament reconstruction using an autograft, either a free bone patellar tendon bone graft or a Semi Tendinosus and Gracilis (STG) tendon free hamstring graft, is the most common surgical treatment. Tibial fixation region of the graft is presumed to be a delicate point in arthroscopic ACL reconstruction. There, can be a chance of graft pull out from the tibial tunnel before actual healing of the graft-tunnel can occur. To avoid this problem, the technique of tibial attachment preserved hamstring graft can be used instead of free hamstring graft. Aim: To evaluate and compare the functional outcome of patients who underwent ACL reconstruction with either a free hamstring graft or by tibial attachment preserving hamstring graft. Materials and Methods: A prospective interventional study was conducted in the Department of Orthopaedics, Swami Rama Himalayan University Hospital, Dehradun, Uttarakhand, India, over a period of one year (July 2019-July 2020). A total 52 patients were included and they were divided into two groups. Group A (tibial attachment preserving hamstring graft) and Group B (tibial attachment sacrificing hamstring graft) with each group comprised 26 patients. Patients were assessed with Lysholm score at 6, 12 and 24 weeks of follow-up. For determining the statistical difference between the two groups Independent Student's t-test was used, whereas for more than two groups Analysis of Variance (ANOVA) test was used and a p-value <0.05 was considered to be significant. Results: The mean age of patients in group A was 30.73 +/- 10.02 years whereas in group B it was 29.54 +/- 9.84 years. For group A, mean Lysholm score at 6 weeks was 73.23 +/- 8.37, at 12 week score was 86.85 +/- 5.93 and at 24 week score was 95.58 +/- 4.91. For group B, mean Lysholm score at 6 weeks was 74.15 +/- 5.82, at 12 weeks score was 87.46 +/- 5.95 and at 24 weeks score was 96.92 +/- 3.61. Post-hoc analysis showed that there was a significant difference in mean Lysholm score {between preoperative and other time points (p<0.001, respectively)} for both the groups but there was no significant difference in Lysholm score at 6 weeks (p=0.646), 12 weeks (p=0.710) and 24 weeks (p=0.265) when compared between the two groups. Conclusion: ACL reconstruction using hamstring autograft with preserved tibial insertion resulted in no statistically significant difference in functional outcome as compared with free autograft.