Kissing Spine- what is it?

Kissing spines (known as overlapping or impinging dorsal spinous processes) involves the bones along the spine from the withers to the point of the hip. With Kissing spine these bones have a smaller gap between them or are touching causing pain. It is often diagnosed after back pain is noticed either when the saddle is placed on the back, under ridden work or when the back is palpated.

Kissing Spines with some overlapping DSP’s (dorsal spinous processs)

How do I know my horse has kissing spine?

Clinical signs for kissing spine include several different symptoms including:

  • Back pain when pressure is applied along the spine and muscles adjacent
  • Discomfort, tail swishing and ears back when the saddle is placed on the back
  • Changes in ridden work such as unwillingness to go forward, stopping when jumping, bucking or general poor performance
  • Poor musculature along the back and hindquarters
  • Subtle hindlimb lameness or sacroiliac pain can also develop as compensatory secondary issues

How do you diagnose it?

Red arrows indicating areas of bone reaction

Diagnosis of kissing spine is by radiography or x-ray of the back focusing on the dorsal spinous processes. This definitively shows us if there are any areas of bone reaction (which shows up as whiter areas of bone) or bone that may be touching which could be causing pain. If there is any doubt that the back pain is being caused by kissing spines we can block the back using local anaesthetic to assess for the presence of pain, or refer the horse for a bone scan to identify any areas of reactive bone over the back.

Are all horses with Kissing spine painful?

Not always- some horses can have no sign of back pain or poor performance but can have reduced mobility in that area which can cause other issues.

What else causes back pain?

The most common cause of back pain is kissing spine, however musculature pain over the back can be caused by an ill fitting saddle or compensatory soreness when a hindlimb lameness is present. Arthritis of the facet joints along the spine between the withers and pelvis have also been reported but are much less commonly diagnosed.

How do we treat Kissing spine?

The treatment is split into two categories- Medical management and Surgery. Medical treatment is based on making the horse comfortable using steroid injections into the gaps between the spinous processes and adjacent musculature then building up the muscles over the back and hindquarters, lifting the back and reducing the ‘crowding’ of vertebrae. We create an exercise plan tending to use a pessoa or similar system to encourage rounding and raising of the back then introducing lunging with poles and ridden work.

Changes in the dorsal spinous processes when the back is hollow vs when it is raised

If there is minimal improvement with medical management or severe changes on x-rays or pain surgery is then often recommended. Generally surgery is performed standing and involves one of two procedures available. The first is called an interspinous ligament desmotomy- this involves breaking down or decompressing the interpinous ligament which runs between the areas of compression- the theory being if the ligament is no longer being pinched then the pain will stop. If there is significant overlapping of vertebrae then removal of either the front of the affected vertebrae or a significant portion of it may be recommended- this is significantly more invasive and carries an increased recovery time.

Interspinous ligament highlighted in orange

What should I do if I think my horse has kissing spines?

All of our vets are happy to examine your horse if you are suspicious of kissing spines, we may ask for them to be trotted up or ridden at the examination and we are able to x-ray the back at your yard or field if required. Please call us on 07747 771182 if you would like to book in or if you have any questions and one of our vets will be able to help you.

Alex x