Tibial Guidewire Insertion Timing- Does it Affect the Functional Outcome in Arthroscopic Anterior Cruciate Ligament Reconstruction? A Prospective Longitudinal Study

Abstract

Introduction: Tibial fixation site of graft in arthroscopic Anterior Cruciate Ligament (ACL) reconstruction has an effect on anterior displacement and internal rotation of the tibia. The position of the interference screw determines the final orientation of the graft. The screw position in turn depends on the position of the tibial guidewire. The tibial guidewire can be placed before introducing the graft or after the graft placement. There are no studies in the literature comparing the outcome of tibial guidewire placement timing in arthroscopic ACL reconstruction. Aim: To compare the functional outcome of arthroscopic ACL reconstruction, with placing the tibial guidewire before and after graft passage. Materials and Methods: This prospective longitudinal study was conducted at Government Medical College, Thiruvananthapuram, India, from February 2020 to January 2021, among patients undergoing arthroscopic ACL reconstruction. A total of 84 patients with an isolated ACL tear, who underwent arthroscopic ACL reconstructionwere followedup for a minimum period of nine months. Two groups were studied, each with 42 patients. In group 1, the tibial guidewire was placed posterolaterally in the tibial tunnel and then the graft was pulled through femoral and tibial tunnels. In group 2, the guidewire was placed after the graft was passed through femoral and tibial tunnels. Functional outcomes were evaluated with International Knee Documentation Committee (IKDC) and Lysholm knee scores after nine months. Statistical analyses were carried out using Statistical Package for Social Sciences (SPSS) statistics version 22.0. Results: The median age of the study subjects were 27 (22;35) years. Fifty nine (70.2%) patients were males. Forty eight (57.1%) patients had left-sided injuries. The majority of injuries (n= 58, 69%) were due to sports injuries. In 14 patients (16.7%), the mode of injury was due to road traffic accidents and in 12 patients (14.3%) it was due to a fall. In the majority of the cases (n=50, 59.5%), the duration between injury and ACL reconstruction was 3 months. The mean IKDC subjective score of group 1 was 86±5.51 and that of group 2 was 81.9±6.64; (p-value=0.003). The mean Lysholm score of group 1 was 84.9±8.73 and that of group 2 was 79.6±9.56; (p-value=0.009). Conclusion: Arthroscopic ACL reconstruction placing the tibial guidewire posterolaterally prior to graft passage has got a better functional outcome compared to placing the guidewire after passing the graft. Prior placement of guidewire before graft ensures the posterolateral position of the interference screw at the tibial tunnel and increases the graft obliquity