Objective—To compare the mechanical characteristics of polymerized caprolactam and monofilament nylon loops with those of the cranial cruciate ligament (CCL) in cattle.
Sample—6 femorotibial joints harvested from 3 cows and suture constructs made from No. 8 polymerized caprolactam, 80-lb test monofilament nylon fishing line, and 450-lb test monofilament nylon fishing line.
Procedures—Joints were cleared of soft tissue structures except the CCL, connected to a load frame, and loaded to failure while measuring force and elongation. Synthetic constructs tested in a similar manner included single-stranded and 3-stranded No. 8 polymerized caprolactam, 3- and 6-stranded 80-lb test monofilament nylon fishing line, and 3- and 6-stranded 450-lb test monofilament nylon fishing line.
Results—The CCL ruptured at a mean ± SD force of 4,541 ± 1,417 N with an elongation of 2.0 ± 0.3 cm. The tensile strength of 3-stranded 450-lb test monofilament nylon fishing line was similar to that of the CCL, rupturing at loads of 5,310 ± 369 N (braided strands) and 6,260 ± 239 N (parallel strands). Elongation was greater for braided constructs.
Conclusions and Clinical Relevance—The 3-stranded cords of 450-lb test monofilament nylon fishing line most closely approximated the strength of the CCL. Marked increases in elongation occur when large-sized materials are constructed in braided configurations, and this elongation would likely not provide stability in CCL-deficient stifle joints. Additional studies are needed to determine whether any of these materials are suitable CCL replacements in cattle.