Arthrodesis of the Equine Proximal Interphalangeal Joint: A Biomechanical Comparison of Two Parallel Headless, Tapered, Variable‐Pitched, Titanium Compression Screws and Two Parallel 5.5 mm Stainless‐Steel Cortical Screws

Abstract

Acutrak-Plus screws may provide an alternative means of fixation for proximal interphalangeal joint arthrodesis.

In VitroBiomechanical Comparison of a 4.5 mm Narrow Locking Compression Plate Construct Versus a 4.5 mm Limited Contact Dynamic Compression Plate Construct for Arthrodesis of the Equine Proximal Interphalangeal Joint

“…Thus, the 4‐point testing performed here does not fully reflect the in vivo scenario. The method of mechanical testing reported differs from some previous pastern arthrodesis studies, that used either axial loading of the limb, in an attempt to simulate in vivo loading, or 3‐point bending . Difficulty in attaining pastern failure in axial loading has been reported, so it was not used for this study .…”

“…Similar to other reports, the articular cartilage of the pastern joint was not removed before instrumentation and testing . This is different than the clinical situation but often used in vitro to avoid potential inconsistencies in the debridement to the subchondral bone.…”

“…The method of mechanical testing reported differs from some previous pastern arthrodesis studies, that used either axial loading of the limb, in an attempt to simulate in vivo loading, 16,18 or 3-point bending. 19,20 Difficulty in attaining pastern failure in axial loading has been reported, so it was not used for this study. 20,21 Rather, we elected to remove all of the soft tissue and perform 4-point bending mechanical testing of the paired constructs.…”

“…Similar to other reports, the articular cartilage of the pastern joint was not removed before instrumentation and testing. 11,16,19,20 This is different than the clinical situation but often used in vitro to avoid potential inconsistencies in the debridement to the subchondral bone. The absence or presence of articular cartilage is potentially an important difference between previously reported studies and could be one cause of the variability in results between studies.…”

An In Vitro Biomechanical Comparison of Equine Proximal Interphalangeal Joint Arthrodesis Techniques: Two Parallel Transarticular Headless Tapered Variable Pitch Screws Versus Two Parallel Transarticular AO Cortical Bone Screws Inserted in Lag Fashion

“…18 In a recent in vitro study, 2 parallel transarticular 5.5 mm cortical bone screws inserted in lag fashion (AO-TLS) were compared with 2 parallel transarticular Acutrak Plus (Acumed, Hillsboro, OR) headless, tapered, variable pitch screws (AP-TS) for the arthrodesis of the equine PIP joint. 19 This study was limited to 3-point bending in a dorsopalmar (plantar) direction in single cycle to failure. There was no significant difference between the mean stiffness and mean failure bending moment for the 2 constructs.…”