An assessment of the tensile properties and technical difficulties of two- and four-strand flexor tendon repairs

This study compares the mechanical properties of locking Kessler and four-strand flexor tendon repairs and examines for difficulties related to technical ability. Two trainee surgeons each carried out 10 locking Kessler and 10 four-strand single-cross flexor tendon repairs on an in vitro porcine model. Outcome measures included gap formation and ultimate forces, operative time and repair bulk. Ultimate force was 81% greater for the four-strand repair compared to the Kessler (52 N, SD 5, versus 29 N, SD 6). Operating times were similar between the two techniques (Kessler 10.0 minutes, four strand 10.1 minutes). Rupture force and operating times improved slightly during the study for the Kessler repairs, but in the four strand repairs results remained stable throughout the study. We conclude that the single-cross four-strand repair tolerates superior loads yet is no more technically demanding than the modified Kessler, and can be reliably performed without additional operating time.