The size of tibial footprint of anterior cruciate ligament and association with physical characteristics in Asian females

The tibial footprint is important for preoperative planning of operative technique and graft selection. Knowledge of tibial footprint in Asians is scant including the relationship between tibial footprint and physical characteristics. The aim of this study was to identify the size of the anterior cruciate ligament (ACL) tibial footprint and the proportion of size < 14 mm, and to evaluate the association of tibial footprint with physical characteristics in Asian females. A total of 127 patients with intact or minimal change in ACL were included. The tibial footprint was carefully measured during total knee arthroplasty. As potential predictors, leg length, femoral length, tibial length, and anteroposterior and mediolateral diameter of the proximal tibia were measured on radiographs, as well as body height and weight. The relationship of ACL tibial footprint length < 14 mm with physical characteristics was analyzed using univariable and multivariable logistic regression. The tibial footprint was 13.8 mm (range 10.0-18.0) in length and 9.8 mm (range 6.3-13.5) in width. The proportion of footprints < 14 mm in length was 53.5 %. Patient height, leg length, femoral length, and tibial length were correlated with tibial footprint. Tibial length was the best predictor of ACL tibial footprint length < 14 mm (Odds ratio 1.75; 95 % confidence interval 1.08-2.82). Tibial footprint size shows a large variation with a high proportion of < 14 mm length. Tibial length can help predict the ACL tibial footprint in the preoperative planning of ACL reconstruction.