The SK ESF Advantage
by IMEX Veterinary
Isolated connecting rod testing does not tell the entire story. Actual testing of ESF frame models confirms that frame simplification can be accomplished by incorporating strong connecting rods. Typical ESF frames were constructed of large SK components with medium pins as well as medium KE components with medium pins. By comparing frames with equivalent geometries and identical pins, the actual impact of the connecting rod on mechanical performance can be seen (Bronson, D.G., Ross, J.D., Welch, R.D., Proceedings of Veterinary Orthopaedic Society Annual Meeting, 1999). Recently published mechanical testing of currently available veterinary ESF devices confirms the ability of larger diameter connecting rods to allow clinical use of simpler frame geometries (White, D.T., Bronson, D.G., Welch, R.D.: A Mechanical Comparison of Veterinary External Skeletal Fixation Systems. Veterinary Surgery 32:507-514, 2003).
The goal of the SK ESF System is not to generate ever-increasing frame stiffness, but to achieve clinically appropriate strength while using simple, patient friendly frames.
FIGURE A | The large SK Type l-a frame exceeds the strength of the KE Type l-a, KE Type l-b and the modified Type II KE (one full-pin per fragment and the balance half-pins). The large SK Type I-b provides 60% of the axial strength and stiffness of the most complex KE frame (Type lll)
FIGURE B | The large SK Type l-a frame exceeds all KE frames except the Type lll.
FIGURE C | Comparable Type l-a and l-b frames have an approximate fourfold increase in strength when constructed utilizing the large SK rods.