Mechanical Strength of the Side-to-Side Versus Pulvertaft Weave Tendon Repair

Abstract

Purpose-The side-to-side (SS) tendon suture technique was designed to function as a repair that permits immediate post-operative activation and mobilization of a transferred muscle. This study was designed to test the strength and stiffness of the SS technique against a variation of the Pulvertaft (PT) repair technique.Methods-Flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) tendons were harvested from four fresh cadavers and used as a model system. Seven SS and six PT repairs were performed using the FDS as the donor and the FDP as the recipient tendon. For SS repairs, the FDS was woven through one incision in the FDP, and was joined with four cross-stitch running sutures down both sides, and one double-loop suture at each tendon free end; for PT repairs, FDS was woven through three incisions in FDP, joined with a double-loop suture at both ends of the overlap, and four evenly spaced mattress sutures between the ends. Tendon repairs were placed in a tensile testing machine, pre-conditioned and tested to failure.Results-There were no statistically significant differences in cross-sectional area (p=0.99) or initial length (p=0.93) between SS and PT repairs. Therefore, all comparisons between methods were made using measures of loads and deformations, rather than stresses and strains.. All failures occurred in the repair region, rather than at the clamps. However, failure mechanisms were different between the two techniques-PT repairs failed by the suture knots either slipping or pulling through the tendon material, followed by the FDS tendon pulling through the FDP tendon; SS repairs failed by shearing of fibers within the FDS. Load at first failure (p < 0.01), ultimate load (p < 0.001), and repair stiffness (p < 0.05) were all significantly different between SS and PT techniques; in all cases the mean value for SS was higher than for PT.Discussion-The SS repair, using a cross-stitch suture technique, was significantly stronger and stiffer compared to the PT repair using a mattress suture technique. This suggests that using SS repairs could enable patients to load the repair soon after surgery. Ultimately, this should reduce the risk of developing adhesions and result in improved functional outcome and fewer complications in the acute post-operative period. Future work will address the specific mechanisms (for example, suture-

Biomechanical and Dimensional Measurements of the Pulvertaft Weave Versus the Cow-Hitch Technique

“…There was no difference, however, in cross-sectional area between both techniques. 2 The double-loop technique also had a significant difference when compared with the PW regarding ultimate strength. Regrettably, it too is at a disadvantage in that the repair looks like a knot making it bulky, and thus creating greater friction with surrounding tissues.…”

“…A commonly described failure is instability of the sutures leading to elongation of the junction. 2 Also, the weave is bulky, which creates a greater amount of friction on the surrounding tissue. 8 It is thought that reducing this bulkiness improves the ability of the repaired tendons to glide through the surrounding tissue, resulting in less friction and thus fewer adhesions.…”

Simultaneous powering of forearm pronation and key pinch in tetraplegia using a single muscle-tendon unit

“…In order to insure stability and permit immediate mobilization, which is critical when performing transfers through IOM, the overlap between the donor and recipient tendon was 5 cm (Fig. 2, inset) (Brown et al, 2010). For the traditional group (palmar transfer), all procedures were the same with the exception that BR was passed palmar to the radius and secured to FPL.…”

The rare injury of a closed digital extensor tendon avulsion of the third finger at its musculotendinous junction: Case presentation and brief overview of literature with regard to general, specific and practicable aspects to extensor tendon surgery involving tendon transfer procedures

“…A biomechanical study revealed that both the Pulvertaft 3-and 4-weave repair could allow early and safe active mobilization [85]. The main problem with the Pulvertaft weaving is failure by the suture knots either slipping or pulling through the tendon, and a step-cut side-to-side tendon suture is an alternative to reduce bulkiness that is mostly observed with the use of the Pulvertaft weaving [86,87].…”