Sagittal distal limb kinematics inside the hoof capsule captured using high-speed fluoroscopy in walking and trotting horses.

The research uses a high-speed fluoroscopy system to study the movement of the distal limb inside the hoof of horses when they walk and trot. The study aims to provide a deeper understanding of ‘internal’ distal limb kinematics, as previous studies have been constrained due to visibility issues with the hoof capsule.

Objective and Methodology

• The primary objective of the research was to explore the distal limb kinematics within the hoof capsule of horses using high-speed fluoroscopy (HSF), overriding the challenges with the standard methods incapable of visualizing within the hoof capsule.
• With a sample size of six non-lame horses, at both walk and trot, detailed kinematic data of the distal limb was gathered with the help of HSF placed over a force plate.
• The angles of the dorsal proximal interphalangeal joint (PIPJ) and the dorsal distal interphalangeal joint (DIPJ) were recorded at a few specified intervals namely toe-on, 25%, 50%, and 75% of stance.

Findings

• The results showed an overall extension of the PIPJ and DIPJ during the stance.
• The range of motion (ROM) during the stance of the PIPJ and DIPJ showed significant differences between walks and trots and also notable variations in inter- and intra- horse angles.
• The observed ROM of the PIPJ was found to be consistent with earlier studies in the literature, while the ROM for the DIPJ was lesser than previously reported values.

Implications and Future Work

• The findings and data from the HSF system provided a new approach for assessing the kinematics of the distal limb within the confined hoof capsule.
• This groundbreaking approach has opened doors for future research to estimate the strain on tendons and ligaments within the hoof capsule, attempting to uncover the common causes of lameness in horses.