Anthropometric Measurement of Tunnel Lengths for Anterior Cruciate Ligament Reconstruction in Chinese

Introduction There is a lacking of tunnel length measurements data for primary anterior cruciate ligament (ACL) reconstruction in the Chinese population. Different tunnel lengths affect the security of the tendon graft fixation as well as bone—tendon healing. Long-term result may then be compromised. Double-bundle ACL reconstruction will work well if both grafts have good quality, size, and tendon—bone fixation. Proper rehabilitation is also an important element. However, the femoral tunnel length for posterolateral bundle will have a higher prevalence of inadequate graft bone contact because of its orientation, especially in the Chinese population with smaller knees compared with the Western population. Methods From January 2009 to June 2011, 148 cases of ACL reconstruction have been performed in our hospital. After excluding cases with revision, isolated bundle (anteromedial or posterolateral), and four-strand hamstring graft single-bundle ACL reconstructions, we recruited 48 cases with primary double-bundle ACL reconstruction in the study of tunnel lengths. Hamstring tendon autografts (semitendinosus and gracilis) were used. A small cohort study with Level 3 evidence was carried out. Results In 31.3% (15/48) of patients, inadequate graft—bone contact was observed in the posterolateral bundle using the available shortest Endobutton CL 15 (Endobutton continuous loop fixation device; Smith and Nephew, Andover, Massachusetts, USA) in femoral tunnel fixation. Conclusion ACL reconstruction is a complex procedure that relies on good tendon graft length, graft size, tunnel length, and secure fixation method. Inadequate posterolateral tunnel length may contribute to short-term complications as well as long-term failure. Further refining of the choices of graft, better orientation of tunnels, and a better fixation method may be important, especially in the Chinese population with smaller knees.