Cross-sectional area and strength differences of fiberwire, prolene, and ticron sutures

Flexor tendons should be repaired with suture material strong enough to permit early motion and small enough for the resulting knot to allow unimpeded tendon glide and healing. This study sought to define differences in cross-sectional area and knotted tensile strength among Fiberwire, Prolene, and Ticron sutures.

Five strands, each of 3-0 and 4-0 Prolene, Ticron, and Fiberwire sutures, were embedded in polymethylmethacrylate and sectioned in a linear precision saw to obtain 10 cross-sections of each material and size. These were examined by scanning electron microscopy and digitally analyzed for cross-sectional areas. Ten strands of each suture material and size had a single throw knot placed, and they were loaded to failure in a micromechanical tester.

Prolene and Ticron cross-sections were circular. Fiberwire was noncircular. The 3-0 Fiberwire sutures had greater cross-sectional area than the 3-0 Ticron sutures (p < .001), which in turn were larger than 3-0 Prolene (p < .05). The 4-0 Fiberwire cross-sectional area was also greater than that of 3-0 Ticron and Prolene (p < .05). After relating knotted tensile strength to cross-sectional area, Fiberwire was 10% stronger than Prolene, and 25% stronger than Ticron.

Fiberwire is not only stronger, but also larger than other sutures in the same or even higher suture size category. Failure to meet the United States Pharmacopeia standards for suture diameter is declared in the product information sheet, although surgeons may not be aware of these size variations. Suture size definitions are currently based on diameter, a consistent measure for circular monofilament sutures, but not for braided or noncircular sutures.