Q: What are kissing spines?

A: Kissing spines are a relatively common cause of back pain in horses.

Individual vertebrae in the horse’s spine are connected by ligaments and surrounded by muscles. Each vertebra has a bony projection that points up towards the skin’s surface, called the spinous process. Usually, these spinous processes are evenly spaced, allowing the horse to move and bend easily through his spine. However, in the case of kissing spines, these spinous processes are too close together and can even begin to touch. This, as you would expect, causes pain and reduces mobility.

Signs of kissing spines are pretty similar to those seen with any kind of back problem in a horse. For instance, the horse is likely to show pain when being saddled up or mounted and may well show changes under saddle, like a reluctance to go forwards, struggling to canter or bucking.

Kissing spines are diagnosed through a full history and physical examination, a lameness investigation including local anaesthetic injection and then imaging of the back, usually with X-Rays and ultrasounds.

There are various treatments available for kissing spines. Working in hand with a physio can be helpful to build the topline and core to give more stability to the spine. Muscle relaxants administered by mouth can help the horse develop a nice rounded outline in this in-hand work. Anti-inflammatories can also be used, either orally or through injection between the spinous processes or along the muscles of the back. These more conservative treatments can often yield very impressive results. However, surgery remains a useful option in some cases and is designed to widen the spaces between the spinous processes. This is now commonly done in the sedated but standing horse, which removes the need for general anaesthetic.