Horse Thoraco-Lumbar

Thoraco-Lumbar

Another highly stressed region of the spine is the T-L junction which joins the 18 thoracic vertebrae to the 5 lumbar vertebrae. The region includes many ligaments, fascia, nerves, blood vessels, lymphatics and of course the dorsal and ventral muscles, such as the longissimus, psoas, iliocostal, and deeper spinal muscles. The region plays an important role in transferring propulsion and power form the hindquarters as well as being able to reserve the ability to be flexible which allows the horse’s movement to be smooth and efficient.

 

As with most regions of the spine in performance horse, the thoraco-lumbar is subject to states of secondary hypertonicity caused by pain from lower limb soreness. In the thoraco-lumbar region this secondary guarding results from hind limb pain, such as the:

 

• Mid thoracic region from hock pain.
• Thoraco-lumbar region from hind fetlock, stifle or sacro-iliac pain.

 

Other injuries which can initiate thoraco-lumber hypertonicity are:

 

• Longissimus strains on the transverse lumbar vertebrae.
• Strains and tears in the posterior gluteal seam.
• Strains and tears in the hamstrings.

 

Injuries can directly develop on the dorsal thoracic and lumber spines, ligaments, muscles and nerves. Injuries range from bruising of the spinal processes, supraspinous ligament and longissimus form rolling on a hard object such as a rock in the paddock. On palpation there is an intense guarding/hypertonicity which is designed to protect the injured region, this is also known as back splinting, however the disadvantage to this function is that the tightened muscles restrict the rate of blood flow through the region which predisposes the spine to spondylosis and the soft tissues to scar tissue build up.

 

Degenerative disorders of the thoraco-lumbar region include spondylosis, scar tissue build up, muscle atrophy and degenerative disorders of the vertebral joints are all issues which effect older horses that have had ‘wear and tear’ of the region through their performance career.

 

This region with the wither is a common area stressed by the placement of saddles and in particular improper fitting saddles and saddle tack. Localised hypertonicity, white hairs, swelling, oedema, hard spots, scar tissue build up and regional atrophy are all symptoms that are stressed from improper saddle placement. The horse may dip down when the saddle is first placed on the back or to palpation when the hands are first placed on the back. Many of these painful issues of the thoraco-lumber region and the back in general can cause the horse to manifest many behavioural issues in dealing with this soreness, genuine horses may suddenly change their behaviour such as a sudden refusal of a jump, uncommon shying or bucking and a change their action which can all have roots from pain in the thoraco-lumbar region.

 

The acupuncture work-up can be very valuable in localizing the cause of the pain and hypertonicity in the thoraco-lumbar region before any of the known clinical signs manifest and before the problem manifests as bad as a lameness. It is also important in determining weather the hind limbs are the cause of the thoraco-lumbar spinal stiffness and allow for further treatment of the cause which can be looked into by the vet.

 

Benefits of acupuncture include:

 

• Pain reduction.
• Increased spinal joint range of movement, through muscle relaxation and increased joint capsule elasticity, this helps to maintain the flexibility and rigidity balance needed for proper spinal function.
• Reduction in secondary jarring stress on the lower hind limb limbs.
• Increased blood flow through the region which is needed to resolve scar tissue and bone build up which restricts spinal mobility.
• Raised levels of circulating cortisol.

Latest Blog