A study of the biomechanical properties of the adult equine linea alba: relationship of tissue bite size and suture material to breaking strength.

This research article focused on identifying the optimum size for needle insertion (otherwise known as tissue bite size) and the strongest suture materials when operating on the adult equine’s linea alba. They found that a tissue bite size of 15mm resulted in the highest breaking strength, and that the closing strength varied depending on the thickness and position of the linea alba. The study used humanely euthanized adult horses as test subjects.

Methodology

• The study used data from 16 adult horses, with soft tissues removed from the abdominal fascia (outer layer of the muscle)
• They divided the entire linea alba (middle line of the abdomen) into test sections and conducted biomechanical tests on each one
• Tissue bite sizes ranged from 3mm to 21mm; the study sought to identify how their size influenced the breaking strength (the amount of tension a material can withstand before breaking)
• They also tested the stiffness of seven different types of suture materials to determine which were most effective

Results

• The study found that tissue bite size significantly altered breaking strength in a direct, logarithmic pattern
• It accounted for 44% of the variability in breaking strength while linea alba thickness accounted for 24%
• The optimum tissue bite size, defined by a lack of significant gain in breaking strength after a certain point, was found to be 15mm
• Results revealed that there were no differences in breaking strength among horses or between left and right test sections
• The study also found that sections near or at the umbilicus had greater breaking strength and thicker linea alba compared to those more cranial (towards the head)
• Thickness alone accounted for 34% of the variability in breaking strength linked to test section position
• There were no differences in linea alba stiffness among different tissue bite sizes.

Conclusion

• The results of this study could be valuable in improving surgical strategies for operations on the abdominal region of adult horses.
• The optimal tissue bite size for such surgeries was found to be 15mm from the edge of the linea alba, meaning that this should be the goal for tissue bite size in such operations.
• Meanwhile, suture material should be selected for its breaking strength rather than its stiffness, and all suture loops should be thoroughly secured, given that a majority of them failed at the knot during the tests.