Splints A splint is usually associated with injury to the ligament between the second and third, or third and fourth, metacarpal or metatarsal bones, that is, between the cannon bone and either the inside or outside splint bones respectively. When tearing of this ligament occurs due to injury, faulty conformation or faulty nutrition, an inflammation of the outside lining of the splint bone and/or cannon bone occurs. Growth of the splint depends on the amount of original damage and whether the cause has been removed or is continuing to irritate the affected area.

Splints are more commonly found on the inside of the front and the outside of the hind cannons because of the anatomical make-up of the knee and hock respectively. Consequently, any change in conformation that places more weight on the medial aspect (inside) of the knee joint or the lateral aspect (outside) of the hock joint will have a tendency to produce splints.

Other factors influencing the occurrence of splints include inherited smallness of the cannon bone, lateral displacement of the cannon bone (bench knees) and occasionally it is seen in bow-legged horses with closer than normal feet. Splints also occur by injury through carrying too much weight at too young an age, and by any other cause of excessive strain on the splint ligaments. The one coming most readily to mind being excessive body weight due to overfeeding and mineral imbalances in show hacks.

Splints may appear when calcium: phosphorus ratios in the feed are not correctly balanced. Treatment relies on removal of the cause followed by surgical shoeing and/or a long rest period. Occasionally, surgery on the splint itself may be necessary. Obviously, where the condition is due to faulty conformation such as bench knees, there is a much slighter possibility that either rest or surgery will effect a permanent cure. All horses treated surgically should be given complete rest for 6 months following surgery and, if applicable, should have their body weight reduced.