Lameness Locator

I would like to introduce this exciting new technology to you as Burlington Equine is the only practice in this area of New England that has this equipment. The Lameness Locator is a gait analysis system that enables a veterinarian to objectively identify lameness issues in horses. The system provides information that indicates whether or not the horse is lame, an amplitude of the severity of the lameness, the limb or limbs involved, and the part of the motion cycle at which peak pain is occurring (impact, mid-stance, or push off).

The technology has been developed by Dr. Kevin Keegan at the University of Missouri Veterinary School. According to Dr. Keegan the goal was to develop an objective way to evaluate lamenesses in real time, that is instead of using static information and a limited ability for a Veterinarian to see all that is happening during a moving evaluation. “There are two reasons why the Lameness Locator® is better than the naked eye,” Keegan said. “It samples motion at a higher frequency (200x) beyond the capability of the human eye (10x to 20x) and it removes the bias that frequently accompanies subjective evaluation.” -

The components are rather simple: 2 accelerometers that attach to the poll area and the pelvis and a gyroscope that attaches to the RF pastern. The information from these sensors is wirelessly transmitted to a tablet with the software and the information is graphically depicted. The sensors sample the data at 200 times per second.

Currently Lameness Locator systems are being utilized in many referral lameness centers in the U.S. including Veterinary Schools as well as in multiple clinics throughout Europe.

Attached accelerometer sensor
Attached accelerometer sensor
Attached gyroscope sensor

The patient is then observed trotting and this can be done in a straight line or on the lunge. The data is transmitted to the tablet and graphically displayed.

Below is an example of the displayed graphs and the interpretations starting with the initial lameness then going through the process of blocking the lameness to determine what was primary and what became more of a secondary concern.

This pattern indicates a strong lameness evident in the RF and LH. They differ in how they show up, that is the RF lameness is evident when the foot hits the ground while the LH is more evident at push off from the ground. This tends to suggest the push off lameness is more secondary to the RF.

At this point due to the obvious RF lameness that was most apparent to the investigator he blocked the RF lameness. This means the Veterinarian numbed the RF foot to try and block or abolish the lameness from this foot.

Following this the horse was re-evaluated.

In this image the RF lameness is no longer apparent; instead, the LF shows an impact lameness. The previous push off lameness from the LH resolved following blocking of the RF which is consistent with it being a compensatory lameness. Notice now that the RH is exhibiting a push off lameness.

Now that the horse became more lame with the LF, and the LH lameness resolved after the RF was blocked, the Veterinarian proceeded with a block and did the same one on the LF as he had done on the RF then re-evaluated the horse.

In the left graph of the front feet the pattern is essentially symmetrical indicating that the RF and LF are landing and pushing off equally. The right graph demonstrates the slight differeences between the RH and the LH. Again due to the low grade nature of the RH pattern it is more consistent with it being a secondary or compensatory issue.

Now the horse is sound in front and the mild RH lameness would be considered more of a secondary or compensatory issue. At this time radiographs and an ultrasound exam would be done followed by some type of treatment.

There are a number of situations where this new technology could be utilized:

  1. When a horse may show some unsoundness, but it's difficult to determine which leg or legs are involved.
  2. In those instances when the rider feels an unsoundness, but it cannot be appreciated through observation.
  3. As an objective method to evaluate the horse's response to nerve or joint blocks while trying to determine the source of the lameness. (see the example above)
  4. During pre-purchase exams to evaluate overall soundness.
  5. Ruling out the presence of a sub-clinical lameness. If we can identify a problem early, locate the source and institute some type of management or treatment plan before it becomes a real issue the potential for resolution is improved.
  6. Prior to an important competition or sale.

In many situations this may not be necessary, but in cases where we really want more information to determine how various components of the lameness are interrelated this will allow us to do just that. Our powers of observation will always be the most important asset in unraveling an unsoundness, the Lameness Locator simply enhances that ability and objectively provides data that we can use to further analyze what we are and are not seeing with just our eyes.