E460
Lameness

1. The last bone in the foot is called the coffin bone, the distal phalanx, or P3.
2. The last joint in the foot is called the coffin joint or the distal interphalangeal joint.

To simplify, the descriptions used from this point on will use the more commonly used terms.

Diagnosing Lameness: There are many different reasons for a horse to become lame. Because of this, even the professionals struggle at times with a diagnosis. However, there are a few basic tips, that if understood, can help even the most casual horse owner become fairly adept at detecting a lameness problem.

Tip #1 - Studies show that most lameness problems are associated with the foot. Therefore, the foot should be the first area of focus. Realize that 60-65% of the horse’s body weight is carried on the front legs, resulting in more problems occurring in the front legs and feet.

Tip #2 - Conformation (how the horse is put together) plays a major role in lameness problems. Initially, the following observations should be made:

1. Is the horse base-narrow, base-wide, toed-in, toed-out, or a combination of the above?
2. Does the horse have calf, bucked, knock, or bench knees?
3. Are the horse’s pastern angles upright or sloping? (see page E544 under "causes.")
4. Is the horse sickle or cow hocked?

(See figures 8-13)

Tip #3 - Observe the horse at rest. Look and feel for heat/swelling or the way the horse is holding a suspect limb. (See figures 1-2.) These little hints will help narrow the possibilities.

Tip #4 - Observe the horse at exercise. Initially, this can be done first at walking speeds, then at a trot or gallop, if necessary. Choose a hard surface to maneuver the horse in straight lines and then in circles.

Tip #5 - Observe the horse from behind, side, and front. As each foot hits the ground, listen for differences in sound on impact. Look for interfering, overreaching, and scalping. (See figure 3.)

Figure 3

The injury on the hind fetlock of this horse indicates interfering.

1. Drop its head when the sound leg hits the ground, and raise its head when the lame leg hits the ground.
2. While working the horse in a circle, the animal will generally carry its head to the outside of the circle if the lame leg is on the inside, and carry its head to the inside of the circle if the lame leg is on the outside.

1. Drop its head when the lame leg hits the ground, and raise its head when the sound leg hits the ground. Again, this allows the horse to shift more of its body weight to the front and off the lame limb during weight bearing.
2. When observing the horse from behind, watch the gluteal muscle region (see figure 4) of the suspect limb. This area will often show a "hip hike" since the animal tries to spend as little time as possible on the lame limb, and will throw its weight quickly off the lame limb.

Figure 4

The circle indicates the gluteal muscle region.

2. Flexing the suspect joint.
3. Placing pressure on the suspect area or tendon.
4. Performing local nerve blocks (should be reserved for a veterinarian).
5. Radiographs (X-rays), nuclear scintigraphy and/or ultrasound (see figures 6 and 7).
6. Joint taps.

* Realize that experience and training are essential to identify animals that are only slightly lame.

Figure 6

Radiograph or X-Ray The arrow indicates a chip fracture.

Figure 7

Ultrasound

1. Rest - This may mean stall confinement.
2. NSAIDS - bute, Ketoprofen, Banamine. See the specific pages in this manual for additional information on each drug.
3. Cold water therapy on the affected area for 15-20 minutes, 3-4 times a day, for swelling and inflammation. This can be done using a hose or a bucket with very cold water.
4. Topical Absorbine or DMSO.
5. Oral glycosaminoglycans (Power-Flex, Flex-free, Cosequin).
6. Corticosteroids injected in the joint. (A veterinarian must perform this.)
7. Surgery