Summary: Even in the highest stability four-strand hamstring (4HS) or BTB ACL reconstruction series, KT 1000 side-to-side differences of ≥2mm are generally seen in at least a third of all knees. We hypothesized that a stronger, stiffer five-strand HS graft using three-strand-Semitendinosus/two-strand-Gracilis, would result in higher stability rates than 4HS using two-strand-Semitendinosus/two-strand-Gracilis.
Materials and Methods: 20 consecutive patients had 5HS ACL reconstruction using 3ST/2Gr. 18 returned for evaluation 89-112 months postoperatively. Results were compared with a previously reported cohort of 133 knees reconstructed by the same surgeon using four-strand HS grafts evaluated at 24-104 months postoperatively. Both had suspensory-cortical- femoral and whip-stitch-cortical-screw tibial fixation. KT-1000, Noyes, Lysholm and SANE ratings were performed.
Results: All 5HS and 4HS knees were clinically stable, with no graft failures or reinjuries. Average KT-1000 side-to-side difference was 0.44mm for 5HS vs. 1.0mm for 4HS for (p = 0.01). A reconstructed knee laxity increase of ≤1mm versus the normal knee was found in 89% of 5HS vs. 66% of 4HS (p = 0.03); of 2-3mm in 11% 5HS vs. 31% 4HS; of 4mm in 0% 5HS vs. 3% 4HS; and of >4mm in 0% 5HS and 4HS. 5HS/4HS clinical ratings were high and did not significantly differ.
Conclusions: 5HS ACLR had higher stability than a high stability 4HS cohort. Since sufficient ST graft is usually available to fashion a 3strand-ST instead of 2strand-ST graft to combine with the 2strand-Gr, we believe 5HS is preferable to 4HS for ACL reconstruction, especially for double bundle techniques.