Core decompression of the equine navicular bone: an in vitro biomechanical study.

This study investigates the impact of core decompression surgery and bone mineral density (BMD) on the strength of horse navicular bones. It discoversthat the surgical procedure significantly decreases the bone’s breaking strength, irrespective of the diameter or quantity of decompression channels.

Objective and Methodology

• The research aim was to understand the effects of core decompression surgery and bone mineral density on the mechanical traits of horse navicular bones. This study is experimental and conducted in vitro.
• The researchers used forelimb navicular bones from healthy 2-5-year-old horses with no observable radiographic irregularities of the lower end of the forelimbs.
• They utilized dual energy X-ray absorptiometry (DEXA) to measure the navicular Bone Mineral Density (BMD). This technique uses two X-ray beams with different energy levels to calculate bone density.
• One navicular bone from every pair was selected as control, and the contralateral test specimen was allocated to one of six treatment groups based on drill bit diameter (3.2 mm or 2.5 mm) and the count of drill channels (1, 2, or 3) produced in the upper edge of the bone.
• These bones were then subjected to a three-point bending test until failure to measure their mechanical strength. This test is used to analyze a rigid material’s ability to absorb force in flexure.

Results and Conclusion

• The statistical analysis demonstrated significant positive connections between BMD and biomechanical data, meaning higher bone mineral density positively influenced the bone’s mechanical strength.
• There was a significant reduction in breaking strength between undrilled and drilled bone pairs, indicating that the core decompression surgery significantly decreased the bone’s breaking strength.
• However, the diameter and quantity of decompression channels did not significantly influence the extent of the reduction in mechanical strength. This suggests that the weakening effect of the core decompression surgery is consistent, regardless of the surgery’s extent (i.e., the size and number of channels drilled).
• The observation concludes that in vitro core decompression surgery significantly weakens the breaking strength of horse navicular bones. This implies that the clinical application of such a procedure should consider the potential reduction in bone strength post-surgery.