From November 1998 to August 2012, a total of 465 primary ACL reconstructions were performed by the senior author (W.N.L.) using autologous hamstring tendons. Drilling of the femoral tunnel was performed via the transtibial portal, and femoral graft fixation was achieved with corticocancellous cross-pin fixation. During this 14-year time period, 2 graft failures (0.4% failure rate) were noted. The first failure occurred in a 19-year-old college football player who at the 6-month postoperative visit had significant quadriceps atrophy. Despite not being cleared to resume sporting activities, the patient went on to play basketball and retore his graft. The second failure occurred in a 32-year-old woman who reinjured her knee in a skiing accident 5 years after her initial procedure. Of note, the patient was completely asymptomatic and had no residual instability prior to the accident. Furthermore, none of the patients without graft failure had subjective or objective findings of rotational instability after transtibial reconstruction. There were no cases of medial-sided pin prominence or iliotibial band friction syndrome secondary to cross-pin use.
From September 2012 to October 2013, there were 69 primary ACL reconstructions performed by the senior author (W.N.L.) using an accessory anteromedial portal for the preparation of the femoral tunnel along with cortical suspensory femoral fixation. During this 13-month time period, 7 graft failures (10.1% failure rate) were noted (Table 1). These occurred in 5 male and 2 female patients, with a mean age of 18.8 years. All patients were highly competitive high school or college athletes and sustained their initial injuries while participating in their sport. They all underwent physical therapy prior to reconstruction to regain range of motion and quadriceps strength, and underwent surgery at an average of 4 weeks after injury. All 7 patients underwent uncomplicated ACL reconstruction with at the least a size 8 mm-diameter quadrupled hamstring autograft, and none of them had concomitant meniscal or chondral injuries. In addition, there was no compromise of the posterior wall in any cases. The standard postoperative physical therapy protocol, as previously described, was used to guide rehabilitation, and patients were cleared to return to competition at an average of 8.4 months postoperatively. Of the 7 cases, 6 sustained a retear of the graft within 2 weeks of being cleared for full competition, at an average of 8.8 days. The final patient retore the graft 10 months after being cleared to return to sport. In all 7 cases, graft failure occurred while the patient was competing in their respective sport. Furthermore, in each of the cases, graft failure occurred in the central portion of the graft, corresponding to a midsubstance tear.