The Use of Five-strand Hamstring Autograft to Increase the Graft Size in Anterior Cruciate Ligament Reconstruction - a Prospective Randomized Controlled Trial

Anterior cruciate ligament (ACL) reconstruction is one of most commonly performed orthopaedic surgeries. Several options for graft choice are available and autologous single bundle hamstring graft is most commonly used. Variability exists among patients in terms of hamstring size, and therefore the graft diameter. Recently there has been an increasing amount of literature correlating the hamstring graft diameter with the graft failure rate \[1-4\]. They concluded that graft exceeding 8mm in diameter is associated with a significant lower risk of graft failure. There has been study showing that Asian patients were indeed 'different' from the Caucasians. Ho et al published his findings on Singaporean patients showing that the median graft diameters for female and male patients were 7mm and 8mm respectively \[5\]. A retrospective review our patients undergoing ACL reconstruction in our department over the past 10 years has shown that the mean graft diameter was 7.8mm (range, 5.5-10mm). The conventional way of four-strand hamstring autograft is done by doubling both the semitendinosus and gracilis tendons to provide a quadrupled graft. Several techniques have been described to increase the size of the hamstring graft. One of those is the -strand hamstring graft, in which the longer semitendinosus tendon is tripled with the shorter gracilis tendon doubled to produce a 5-strand configuration. We hypothesized that the 5-strand hamstring graft would provide a graft of significantly larger diameter than the conventional quadrupled autograft.