Spinal movements in horses with back pain

Back pain may decrease performance in sport horses. Essential information collected by frequently used diagnostics, such as anamnesis, regional anesthesia, radiography or ultrasound are sometimes insufficient to diagnose the origin of the back problem. Knowing the relationship between the location of back pain and a change in back movements may support understanding and diagnosis of back dysfunctions and gait insufficiencies in horses.

To evaluate if back pain results in a consistent change in back movements, this study measured eight asymptomatic warmblood riding horses. They were measured before and after inducing back pain in the left longissimus dorsi muscle with an injection of lactic acid. To determine the vertebral movements the horses were measured during trot and walk on a treadmill.

Movement of the thoracic back was significantly more extended at both gaits. The back was more bent to the symptomatic left side and additionally, the pelvis rotated more to the left. The tension of the muscle pulls the thoracic spine to a lateral, extended curve. Compensation in both arthrogenic and muscular structures was observed.

This study shows a possible clinical relevance in localizing problems in back kinematics that are difficult to detect for the human eye, by gait analysis systems.

> J. Wennerstrand et al, spinal kinematica in horses with induced back pain, veterinary and comparatice orthopaedics and traumatology (VCOT), 2009: issue 6, 448-454. All rights reserverd to: Vet Comp Orthop Traumatol. Click here for the Pubmed summary