Biomechanical Analysis of Accessory Tendon Graft Augmentation for Primary Gastrocnemius Tendon Reconstruction in Dogs

Introduction: Gastrocnemius tendon (GT) injury is the most common surgical tendinous disease in the dog. Within the human literature, use of surrounding autologous musculotendinous grafts has been reported. The objective of this study was to evaluate the effect of accessory tendon graft (ATG) augmentation as an adjunct to a core locking-loop (LL) and epitendinous suture (ES) repair in a canine GT model.

Materials and Methods: Twenty-two GT musculotendinous specimens were randomly divided into two groups. Following transection, paired GT were repaired with LL+ES alone or with concurrent ATG augmentation. Yield, peak, and failure loads, tensile loads required to create 1- and 3-mm gapping, and failure modes were evaluated.

Results: Yield (p < 0.0001), peak (p = 0.0001), and failure loads (p = 0.0003) were greater when ATG was used for repair. Greater force was required to cause 1 mm (p = 0.0001) and 3 mm (p = 0.0002) gap formation in the ATG group; however, the frequency of gap formation did not differ between groups. All repaired constructs failed exclusively by suture pull-through.

Discussion/Conclusion: Autologous ATG augmentation as an adjunct to primary GT repair increased yield, peak and failure forces by approximately 1.6x, 1.9x, 1.8x, respectively and required 2.1x greater force to cause 1- and 3-mm formation compared with LL+ES repairs alone. Study limitations include those inherent to its ex-vivo design, such as the inability to assess normal processes of tendinous healing. ATG augmentation should be considered as an autologous method to support and strengthen the primary GT repair. These Results justify further studies to determine the effect of ATG on clinical function following graft harvest in dogs.

Acknowledgements: There was no proprietary interest or funding provided for this project.

Publication History

Article published online:
26 October 2022