POOR PERFORMANCE WORKUP

This is a case of a 10 year old thoroughbred gelding which presented to Towcester Equine Vets for poor performance issues (lack of impulsion, unwillingness to work in an outline, poor jumping technique).

The lameness/poor performance examination consists of the following steps:

Step 1: Physical examination.

The horses conformation is assessed for abnormalities and asymmetry.

This horse had a poorly muscled topline with a dipped back. The horse was very sensitive to palpation of his back and pelvis.

Step 2: Trot up in hand.

The horse is assessed at walk and trot in a straight line.

A mild right hindlimb lameness was seen on a firm surface in a straight line.

Step 3: Flexion tests.

Flexion tests are performed on all four limbs. They are tools that help us further localise site(s) of pain. This horse was positive to both hindlimb flexion tests.

Step 3: Evaluate on lunge on soft and firm surfaces.

The horse is assessed on the lunge on a firm and soft surface. Certain conditions are more obvious depending on the surface.

This horse was bilaterally lame behind. The lameness was worse on a firm surface. In canter on a soft surface there was poor separation of the hindlimbs. The canter lacked forward impulsion.

Step 4: Ridden evaluation.

In poor performance cases we usually request to see the horse ridden. Under tack this horse lacked impulsion and was reluctant to accept the contact and work in an outline. In canter the horse appeared uncomfortable and tended to come above the bit and resist contact.

Step 5: Diagnostic analgesia/Blocking.

Local anaesthetic was infiltrated into the lower hock joints (tarsometarsal joints). The horse was evaluated again in hand and on the lunge and under tack. This improved the lameness by about 70%. The trot and canter still lacked impulsion. The sacroiliac joints were then blocked. The horse was evaluated 45 minutes post blocking. This resolved the lameness. The quality of the trot and canter significantly improved. We can therefore say that the cause of the lameness is hock and sacroiliac joint pain. Often sacroiliac joint pain is seen in horses with hock pain and is usually secondary. In order to ascertain the cause of the pain we need to perform diagnostic imaging (radiology and ultrasonography).

Step 6: Diagnostic imaging.

Radiographs were taken of the horses dorsal spinous processes due to sensitivity. The dorsal spinous processes (DSP’’s) are the bony part of the horses back where ligaments and muscles attach and allow for movement of the back. Radiographs revealed one area of very close DSP’s. The closeness of the spinous processes are responsible for the sensitivity in his back. Radiographs were also taken of both hocks. This revealed some very mild bony changes consistent with early onset degenerative changes in the hocks joints. Sometimes a horse can have hock pain and show no radiographic abnormalities. The aim of medical treatment with corticosteroid in these cases is to slow/halt the degenerative process.

Step 7: Treatment

The following areas were medicated/infiltrated with corticosteroid.

1: DSP’s

2: Hocks

3. Sacroiliac joints

The aim of medical treatment is to reduce inflammation and therefore pain. This facilitates the horse to exercise correctly during his rehabilitation program. This horse underwent an intensive physiotherapy and rehabilitation program. He was evaluated regularly prior to increasing his workload. He is now back in full work and competing successfully.

This is a good case showing how multiple areas of pain are often responsible for hindlimb lamenesses and poor performance issues as the horse compensates for pain in one area resulting in dysfunction in other areas. Performance examinations can be very helpful in picking up potential problem areas allowing intervention before other areas also become affected.