Flexion test of the metacarpophalangeal and interphalangeal joints and flexion angle of the metacarpophalangeal joint in sound horses.

The research paper primarily investigates the use of a device called ‘Flextest’ to assess the effects of different traction forces and traction times on flexion tests conducted on distal limb joints of horse’s forelimbs. The tests revealed that an optimal traction force of 100 N for 1 minute does not harm the horse and a slight positive response to this does not necessarily indicate a clinical issue in a horse without any other symptoms or radiographic anomalies.

Flextest Device and its Use

• The study utilises a measuring instrument called ‘Flextest’ to monitor the influence of different amounts of traction force and duration applied during flexion tests. These tests are carried out on the distal limb (forelimbs) joints of horses.
• The device’s purpose is to generate reproducible measurements that could be used in vetting or diagnosis of conditions affecting the equine distal limb joints.

Optimal Force and Time for Flexion Test

• After careful testing, the research concludes that the ideal force for a flexion test is 100 Newton (N) applied over a single minute. This exertion and timeframe are declared to be safe and not cause harm to the horse.
• Applying even a higher force (150 N) was found not to be damaging. This indicates that such a diagnostic method can be used without the risk of injury to the horse.

Significance of Flexion Responses

• The research showed that a slight positive flexion response (using 100 N/1 min) in a horse does not have clinical relevance if the horse does not demonstrate any other clinical symptoms or any radiographic abnormalities. This finding could help in eliminating false positives during diagnosis.
• The study suggests that veterinarians might want to consider other symptoms or conduct further tests before making a diagnosis when a marginally positive flexion response is observed.

Dependence on Other Factors

• The research also concluded that individual left and right flexion and extension angles are almost the same and the age of the horse does not affect them. This information can help in the standardization of flexion tests across different horses.
• The study discovered that horses which are stabled and have had a rest period or horses at pasture were less likely to exhibit a positive flexion test than horses that are working. This could introduce another variable that vets may consider when testing.