Lameness Flashcards
Indicators of lameness that owners or vets might look for:
-feel unbalanced
-change in behavior
-hip hike
-head bob
-reluctance to move
What occurs during a physical exam?
-palpations
-flexing
What gaits are horses observed at for lameness?
walk and trot (they are symmetrical)
What characteristics should be observed during movement?
-phase of stride
-foot arc
-how the foot lands
-cranial phase of the stride
-movement of head
-good suspension
-hips are symmetrical
-tracks up well
When the lame leg hits the ground the head will…
raise
When the sound leg hits the ground the head will…
lower
How is the AAEP Lameness Scale used
as a recording system by vets
-records lameness severity before and after nerve blocks evaluation
-records how recovery is going and if the treatment is working the grade should improve
When the lame hind leg hits the ground the hip…
raises
Why is it important for the horse to be led on a somewhat loose lead during lameness evaluations?
the horses head needs to be able to move naturally. If the lead is too tight, the horse may not be able to bob its head when the lame leg hits the ground as it would naturally, hiding the lameness. Also it could cause the head to move unnaturally up and down which could make a sound horse appear lame.
What is the length of time to keep a joint flexed?
30 seconds, then immediately trot off
What would a positive flexion test mean?
that the horse appears to be lame or more lame when jogging after flexing a specific joint
How does a flexion test help identify which part of the lame limb is affected?
the horse will appear more sore after a specific joint is flexed.
-they may be fine after flexing the fetlock but could appear more lame or sore after flexing the knee
-always flex bottom to top
What type of information is generally looked for in the history of a lame horse?
-age
-breed
-sex
-performance history and level
-previous medical history
-previous and current medications
-which leg is lame and for how long
Steps of a general physical exam for lameness:
- look over
- palpate from front to back – check for heat, thickness, reaction/sensitivity, etc.
- check range of motion
- check tail tone
- diagnostics (ultrasounds, xrays, etc.)
A hoof tester is used to identify lameness in what parts of the hoof?
the soft tissue structures withing the hoof capsule
-puts pressure through the sole and along the frog
What hoof problems might taking a digital pulse detect?
-abscesses
-inflammation of the hoof
-laminitis
-traumatic injuries
Where is the digital pulse taken?
from the palmar digital artery at the base of the pastern
Why would it be beneficial to take radiographs after nerve blocking instead of before?
Nerve blocking allows you to better localize the source of the pain so only a limited amount of radiographs need to be taken. It will also make spotting the original pain in the radiographs easier for vets in a smaller more localized area.
What does nerve blocking do?
guides the diagnostic imaging paln which makes the process easier and usually more cost-effective
How does nuclear scintigraphy differ from a radiograph?
it uses an injection of radioactive isotopes and shows more detail
What is the common name for a nuclear scintigraphy
bone scan
What types of tissues does an MRI help image?
soft tissues, joints, spinal disks
What advantages does an MRI have over radiographs?
-MRI’s show small changes and lesions in soft tissue structures
-image quality isn’t degraded by bone or air
-multiplanar imaging
-it is safe (no radiation)
-best soft tissue differentiation
What advantage does a lameness locator have over the visual observations of horses in motion?
-it gives an objective view of lameness rather than subjective
-will detect multiple lamenesses, subtle lamenesses, and determine which lameness (if multiple) is worse
-more direct data
Before doing advanced diagnostics, what are two things a vet might do to determine whether a horse has a lameness in its hoof?
- use a hoof tester to identify a general area of where the horse is sore or painful
- check the digital pulse (and compare to the non-lame limbs) and check for heat
The process of nuclear scintigraphy
(bone scan) An IV radioisotope is injected into the horse’s bloodstream. A gamma camera is then used to look for active radioisotope uptake in bones, that are remodeling (or have increased in cellular activity)
What are the advantages of nuclear scintigraphy of radiographs?
-it can capture areas of the horse that would otherwise be difficult to scan (ie: back)
-it can detect hot spots and lesions at their earliest stages, that would otherwise not yet show up on a radiograph
0 on the lameness scale
lameness not perceptible under any circumstances
1 on the lameness scale
lameness is difficult to observe and is not consistently apparent, regardless of circumstances (e.g. under saddle, circling, inclines, hard surface, etc.)
2 on the lameness scale
Lameness is difficult to observe at a walk or when trotting in a straight line but consistently apparent under certain circumstances (e.g. weight-carrying, circling, inclines, hard surface, etc.)
3 on the lameness scale
lameness is consistently observable at a trot under all circumstances
4 on the lameness scale
lameness is obvious at the walk
5 on the lameness scale
lameness produces minimal weight bearing in motion and/or at rest or a complete inability to move
Essential features of a thorough vet exam include:
-medical history of the horse
-visual appraisal of the horse at rest
-thorough hands-on exam
-application of hoof testers to the feet
-evaluation of the horse in motion
-joint flexion tests
Diagnostic tests include:
-nerve and joint blocks
-radiographs (xrays)
-scintigraphy
-ultrasound
-arthroscopy
-blood, synovial (joint) fluid, and tissue samples
