Funding was provided by the Western College of Veterinary Medicine-Equine Health Research Fund.
Arthrodesis of the Proximal Interphalangeal Joint in the Horse: A Cyclic Biomechanical Comparison of Two and Three Parallel Cortical Screws Inserted in Lag Fashion
Article first published online: 6 JAN 2010
© Copyright 2010 by The American College of Veterinary Surgeons
Volume 39, Issue 1, pages 91–94, January 2010
How to Cite
CARMALT, J. L., DELANEY, L. and WILSON, D. G. (2010), Arthrodesis of the Proximal Interphalangeal Joint in the Horse: A Cyclic Biomechanical Comparison of Two and Three Parallel Cortical Screws Inserted in Lag Fashion. Veterinary Surgery, 39: 91–94. doi: 10.1111/j.1532-950X.2009.00614.x
Dr. Delaney's current address is Edmonton Equine Veterinary Services (1998) Inc., 12215 William Short Road NW, Edmonton, AB, Canada T5B 2B7.
- Issue published online: 6 JAN 2010
- Article first published online: 6 JAN 2010
- Submitted December 2007; Accepted March 2009
Objective— To compare the biomechanical cyclic fatigue properties of 2 and 3 parallel transarticular 5.5 mm cortical screws used in arthrodesis of the proximal interphalangeal (PIP) joint.
Study Design— Randomized block design, for horse, fixation method (2 versus three 5.5 mm cortical screws), side (right, left) and end (front, hind) in cadaveric equine limbs.
Sample Population— Cadaveric adult equine fore- and hindlimbs (n=5 pairs each).
Methods— Two parallel 5.5 mm cortical screws were inserted in lag fashion, transarticularly through the PIP joint in 1 limb of a pair, and in the contralateral limb, three 5.5 mm cortical screws were inserted in similar fashion. Constructs were then tested in 3-point bending in a dorsal-to-palmar (plantar) direction using a materials testing machine using a cyclic load of −500 to −3500 N at a rate of 6 Hz.
Results— There was no significant difference in displacement at failure, force at failure or number of cycles between limbs. Forelimb constructs tended to fail at a greater mean displacement than hindlimb constructs but this difference was not significant (P=.06). There was no statistical difference in any tested biomechanical variable between left- and right-sided limbs.
Conclusions— There was no significant difference in the number of cycles to failure for the 2 methods tested.
Clinical Relevance— Two 5.5 mm cortical screws inserted in parallel for PIP joint arthrodesis is surgically simpler, results in comparable biomechanical performance in the current model and should perform as well as three 5.5 mm screws under cyclic fatigue conditions.