Biomechanical Comparison of Lasso, Pulvertaft Weave, and Side-by-Side Tendon Repairs

Abstract

The authors' group has developed and used a lasso repair as a substitute to the Pulvertaft weave when joining two tendons for tendon grafts and transfers. This study compared the maximum load, weave time, tendon length required, and bulkiness of the lasso, Pulvertaft weave, and side-by-side repairs. Sixty porcine trotter flexor tendons were used to perform 30 repairs--10 lasso, 10 Pulvertaft weave, and 10 side-by-side. The lasso and Pulvertaft repairs were standardized by initial incision locations, whereas side-by-side repair was standardized to a 2.5-cm overlap. An Instron tensiometer machine was used to test repairs to failure. Maximum load was recorded using data-acquisition software. Weave time, tendon length required, and width at the thickest point of each repair were also measured. The mean maximum load of lasso, Pulvertaft weave, and side-by-side repairs was 155.8, 159.7, and 88.6 N, respectively. Maximum load was equivalent between lasso and Pulvertaft weave repairs. Lasso repair was thicker by 4.9 mm at its widest point than the Pulvertaft weave but, on average, required less than half the weave time and 7 mm less tendon length. The strength of the lasso tendon repair compared well with the Pulvertaft weave and was more convenient to perform. Side-by-side repair was inferior because of its low maximum load. This study suggests that lasso repair may be an alternative to the Pulvertaft weave in tendon grafts and transfers.