Ex vivo comparison of standing and recumbent repair of incomplete parasagittal fractures of the first phalanx in horses.
Authors: Labens Raphael, Jermyn Kieri
Journal: Veterinary surgery : VS
Summary
# Editorial Summary Incomplete parasagittal fractures of the first phalanx are common high-motion injuries in horses, yet optimal repair protocols—particularly regarding weight-bearing during recovery—remain unclear. Labens and Jermyn conducted an ex vivo biomechanical study using 20 cadaver forelimbs to compare fracture gap reduction and soft tissue positioning when lag screws were placed under two conditions: with the limb fully unloaded (simulating recumbent repair) and loaded to 38% of body weight (simulating standing repair), with computed tomography and force-sensitive resistor technology used to quantify outcomes. Fracture gap widths showed no significant difference between standing and recumbent repair simulations when controlling for loading weight, implant position and animal age, nor did force distribution patterns differ meaningfully between groups; however, weight-bearing did shift the extensor branch of the suspensory ligament palmarly by approximately 1.5 mm, expanding the safe palmar approach corridor for implant placement. These findings suggest that enforcing strict stall confinement and unloading protocols immediately post-operatively may not be biomechanically necessary for achieving comparable fracture reduction in incomplete parasagittal P1 fractures, potentially allowing earlier controlled mobilisation—though the clinical significance of the subtle extensor branch shift warrants consideration during surgical planning and implant positioning.
Read the full abstract on PubMed
Practical Takeaways
- •Horses can bear weight immediately after standing repair of incomplete parasagittal P1 fractures without compromising fracture gap reduction—stall rest may not be necessary for mechanical stability.
- •Standing repair provides a wider surgical window for implant placement relative to the extensor branch, potentially reducing operative difficulty and soft tissue trauma.
- •These findings support standing repair as a viable alternative to recumbent repair, which may improve practicality and reduce complications associated with general anesthesia and recovery.
Key Findings
- •Standing repair simulation did not produce wider fracture gaps than recumbent repair (P > 0.7), suggesting limb loading during standing does not compromise fracture reduction.
- •Voltage ratio measurements showed no significant difference between standing and recumbent repair simulations (P = 0.27), indicating comparable load distribution across the fracture site.
- •Loading increased the palmar approach window relative to extensor branches (0.804 ± 0.314 cm loaded vs 0.651 ± 0.31 cm unloaded; P < 0.001), improving surgical accessibility.
- •Limb loading altered extensor branch location, which is clinically relevant for safe implant positioning during surgical repair.