In vitro evaluation of allogeneic bone screws for use in internal fixation of transverse fractures created in proximal sesamoid bones obtained from equine cadavers.

The study looks into the effectiveness of using bone screws and pins made from allogeneic (donor) bone in the treatment of fractures in horse’s sesamoid bones, comparing their performance to traditional metal fixtures. The findings suggest these allogeneic screws may lead to better healing and fewer complications.

Methodology

• For this study, 14 forelimbs were used from the cadavers of 3-year-old Thoroughbreds.
• Allogeneic cortical bone fragments were obtained from a male Thoroughbred’s limbs and used to prepare bone screws via a precision desktop microlathe.
• A transverse break was made in the midpoint of each sesamoid bone using a bone-shaping oscillating saw.
• The fractures were then repaired using one of three methods: one allogeneic screw and one allogeneic pin (Type I), two allogeneic screws (Type II), or one stainless steel screw (the control).
• A commercially available materials testing system was used to measure mechanical tension, or tensile strength (TS), of the repaired fractures.

Results

• Average TS measurements for the repair types were: 668.3 N (with a standard deviation SD of 216.6) for Type I, 854.4 N (SD 253.2) for Type II, and 1,150.0 N (SD 451.7) for the control fixture.
• The results indicate that using allogeneic bone screws and pins can successfully fix sesamoid bone fractures.
• While the mean TS of the stainless steel control repairs was higher than that of both allogeneic repair types, the difference between the Type II repairs and the control was not statistically significant.

Conclusions

• The study concludes that allogeneic bone screws may have potential in advancing bone healing and reducing complications in a clinical setting when compared to traditional metal fixtures.
• While the use of stainless steel screws demonstrated the most tensile strength, the difference when compared to two allogeneic screws was not significantly larger.