In Vitro Biomechanical Comparison of Equine Proximal Interphalangeal Joint Arthrodesis Techniques: Prototype Equine Spoon Plate Versus Axially Positioned Dynamic Compression Plate and Two Abaxial Transarticular Cortical Screws Inserted in Lag Fashion

• Published in: Veterinary surgery 2007-12, Vol.36 (8), p.792-799
• Main Authors: SOD, GARY A., MITCHELL, COLIN F., HUBERT, JEREMY D., MARTIN, GEORGE S., GILL, MARJORIE S.
• Format: Article
• Language: English
• Subjects: Animals; Arthrodesis - instrumentation; Arthrodesis - methods; Arthrodesis - veterinary; Biomechanical Phenomena; Bone Nails - veterinary; Bone Plates - veterinary; Bone Screws - veterinary; Cadaver; Comparative analysis; Compressive Strength; Forelimb; Fracture Fixation, Internal - instrumentation; Fracture Fixation, Internal - methods; Fracture Fixation, Internal - veterinary; Fractures, Bone - surgery; Fractures, Bone - veterinary; Horses; Horses - injuries; Horses - surgery; Joint surgery; Movement; Stress, Mechanical; Toe Joint - surgery; Transplants & implants; Veterinary services
• ISSN: 0161-3499; 1532-950X
• DOI: 10.1111/j.1532-950X.2007.00338.x

Objectives— To compare in vitro monotonic biomechanical properties of an equine spoon plate (ESP) with an axial 3‐hole, 4.5 mm narrow dynamic compression plate (DCP) using 5.5 mm cortical screws in conjunction with 2 abaxial transarticular 5.5 mm cortical screws (DCP‐TLS) inserted in lag fashion for equine proximal interphalangeal (PIP) joint arthrodesis. Study Design— Paired in vitro biomechanical testing of 2 methods of stabilizing cadaveric adult equine forelimb PIP joints. Animal Population— Cadaveric adult equine forelimbs (n=18 pairs). Methods— For each forelimb pair, 1 PIP joint was stabilized with an ESP (8 hole, 4.5 mm) and 1 with an axial 3‐hole narrow DCP (4.5 mm) using 5.5 mm cortical screws in conjunction with 2 abaxial transarticular 5.5 mm cortical screws inserted in lag fashion. Six matching pairs of constructs were tested in single cycle to failure under axial compression with load applied under displacement control at a constant rate of 5 cm/s. Six construct pairs were tested for cyclic fatigue under axial compression with cyclic load (0–7.5 kN) applied at 6 Hz; cycles to failure were recorded. Six construct pairs were tested in single cycle to failure under torsional loading applied at a constant displacement rate (0.17 radians/s) until rotation of 0.87 radians occurred. Mean values for each fixation method were compared using a paired t‐test within each group with statistical significance set at P