Spondylitis, Dorsal Spinous Process (DSP) impingement or “Kissing Spines” is
an equine condition effecting the horses back. The vertebrae of the horse’s
spine are normally regularly spaced with a gap between them, Kissing Spine
occurs when the dorsal spinous processes and, to a lesser extent, the
transverse spinous processes of the horse’s vertebrae start to rub together,
causing pain and swelling, especially when the horse is moving, exercising or
carrying weight such as a saddle and rider. The longstanding inflammation
leads to new bone formation of the vertebrae eventually causing touching and
grating of the dorsal spines. The extra bone formation known as ‘bone spurs’
can form on the underside of the vertebrae eventually causing touching and
sometimes even fusion, this is known as Ankylosing Spondylitis.
Kissing spine lesions are most commonly located in the thoracic vertebral
region where the largest dorsal spinous processes are found, but are also seen
in the lumbar area. This condition is very painful when forming but becomes
less so once formed.
There are no scientific facts to prove a specific cause for kissing spine due to
the disease being so difficult to investigate objectively and scientifically. There
are a number of things that are thought to be the cause or contributing factors
of Kissing Spines.
Thought to be included in some of the contributing factors are incorrectly fitting
saddles, back pain due to tight muscles for long periods of time, the horse
slipping or twisting to cause back pain that is not treated, a rider that is too
heavy for the horse or moves around a lot in their seat, poor conformation or
riding with a hollow frame making the horse imbalanced when working, high
intensity disciplines such as dressage and it has even been said that the
disease may be hereditary.
The symptoms of Kissing Spines can often go unnoticed or mistaken for other
problems until the pain becomes so server that the horse reacts intensively.
Objection to being tacked up, either with having the saddle placed on its back
or the girth being fastened is a good indicator. If the horse reacts badly
(bucking or rearing etc.) when being mounted or ridden this could also be a
good indication that something is wrong. Although these are clear symptoms of
kissing spines they could also be down to back pain and therefore it is
important to keep in mind that if the horse has been treated for back pain by the
physiotherapist and the problems continue that further investigation by the vet
would be needed.
Thermography, Ultrasound and radiography are very useful methods for
detecting kissing spines. Different grades of severity can be identified from
radiographs of the abnormal vertebral processes. Grade 1 show lesions involve
only a narrowing of the space between adjacent processes. Grade 2 lesions
show an increase in bone density at the margins of the processes. In contrast,
Grade 3 lesions show loss of bone adjacent to the margins, and Grade 4
lesions involve severe remodelling of the processes, due to chronic and
profound irritation of the structures.
Vets will usually use surgical techniques on Kissing Spine and the procedures
are vastly becoming less invasive as they learn more about the condition. In
most cases vets will require a strict rehabilitation program post-surgery
including a number of weeks box rest, followed by approximately nine weeks of
low intensity movements for the horse.
When treating Kissing Spines post-surgery, Physiotherapy can be used as a
first line treatment as well as in a more supportive role. Massage can be done
to release any tension, muscle spasm or pain.
Different physiotherapy techniques can be used to assist in the treatment either
pre or post-surgery. Massage and stretching will decrease muscle tension,
however care must be taken when using techniques like palpation due to the
nature of the condition. Using Ultrasound is a great way to treat a pinpointed
area that is particularly sore from muscle pain because the Ultrasound will
increase the blood supply to the area, assist with pain killing affects and help to
soften fibrous tissues, preventing scar tissue forming. Care must be taken to
not use the Ultrasound directly over the spine or bony areas as this can cause
discomfort to the horse.
When a horse is on box rest post-surgery it is very susceptible to other
problems occurring. For example fluid can fill the lower limbs due to the lack of
horse’s movement causing inflammation, usually in the fetlock area. As a
physiotherapist you could limit the swelling using massage, stretching and
static magnets. Magnetic boots are a great way to limit the inflammation in the
horse’s legs and can easily be used by the owner. I would only do the forward
stretching of the hind limbs in the case of kissing spine because the other
stretches may cause pain or add further strain to the effected vertebrae.
Consulting with the vet at different points of the horse’s recovery to discuss the
animals progress should be done.
The horse is very likely to have changed its stance/ posture to cope with the
pain. These compensating techniques can be addressed and rectified with the
use of massage and stretches. There will be certain areas of the body where
the horse will have compensated for the pain and put extra weight. Extra
attention may be needed on the Longissimus dorsi, Latissimus dorsi,
Trapezius, Deltoids and Triceps brachii due to this compensation. The
stretching will promote increased circulation, bringing more oxygen and
nutrients to the fibrous tissue, improve the elasticity of the muscles, tendons,
ligaments and joint capsules and will relax and reduce tension in the horse.
As the horse’s exercise increases it is important to keep up to the massage and
stretching with regular visits to assess and resolve any muscle soreness. It is
likely that the horse will only be walked for a number of weeks, however it is
important to organise regular visits at this point, there is a good chance that the
horse might buck or rear once walked. This can lead to muscle damage or
strain. Keeping the horse relaxed and the muscles and joints flexible with
physiotherapy techniques could reduce the risks of any further injuries.
As the exercise intensity increases physiotherapy will play a big part. The horse
will use muscles more intensively and this can cause stiffness, soreness and in
some cases muscle spasm. Regular physiotherapy visits will maintain the
comfort of the horse and assist in the ROM and elasticity of the muscles,
ligaments, tendons and joints. Depending on the severity of muscle atrophy (if
you are called to a horse that has not received treatment throughout its
surgery) other techniques can be used to assist with muscle strength.
Application of Macro-current Electrostimulation can be used to tens different
elements of the sensory nervous system and by doing so increases muscle
strength, re-educates muscle action, increases speed of muscle contraction, as
well as activating natural pain relief mechanisms such as the Pain Gate
Mechanism and the Endogenous Opioid System.
Exercises such as carrot stretches can be left with the owner so they can
continue to keep the horse supple on a day to day basis.