Diagnosing Lameness in the Horse Flashcards
Why perform a lameness exam?
Pre-purchase exam, neurologic disorder, etc
What is lameness? What are some common causes?
An abnormality due to pain
- Caused by neurologic, metabolic, or mechanical problems
What are the 7 classic steps of a lameness exam?
- History
- PE
- Palpation of weight bearing/ non-weight bearing limbs
- Exercise observations
- Flexion tests
- Diagnostic Nerve blocks
- Diagnostics imaging
What is the primary goal of a lameness exam?
To localize and diagnose the lameness
What are you feeling for on a PH/ palpation?
- Weight bearing vs. non-weight bearing
- Symmetry
- Hoof testers
What is the importance of trotting during an exercise observation?
- It is where the gait lameness is graded from
What is the best surface for a lameness exam?
Blacktop/ tarmac
What is a “ down sound” in a forelimb lameness exam?
- Head rises when the LAME limb is weight bearing and drops when SOUND limb is weight bearing
What abnormal motions do you see with a hindlimb lameness exam?
- Head goes down when lame limb is weight bearing
- Gluteal excursion increases in lame limb –> Hip hikes and hip drops
When can a hindlimb lameness be confused with a forelimb lameness?
- When a head and neck nod is present
What parts of the hoof are you testing with hoof testers?
Wall, sole, frog, heels, coronary band
What is a Grade 1 Lameness?
• Difficult to observe, inconsistent
What is a Grade 2 Lameness?
• Difficult to observe in a straight line but consistently apparent under certain circumstances (circling, hard surface, incline)
What is a Grade 3 Lameness?
• Consistently observable at a trot under all circumstances
What is a Grade 4 Lameness?
• Obvious lameness with marked head nod, hitching, shortened stride
What is a Grade 5 Lameness?
• Minimal weight bearing/non weight bearing and inability to move
What are 5 pathognomonic lamensses that can be diagnosed at the walk?
- Peroneus tertius rupture
- Upward fixation of patella (Locking patella)
- Stringhalt
- Fibrotic myopathy
- Sweeney
What is fibrotic myopathy?
Damage to the semimembranosus and semitendinosus resulting in fibrosis of these muscles and inability to contract those muscles
What is stringhalt?
Overexagerrated gait
What sign do you see in a positive flexion test?
Exacerbated lameness
How do you perform a forelimb flexion test?
DISTAL: hold for 30 sec
can give false positives in normal young horses
PROXIMAL LIMB FLEXION: flex carpus for 60 secs
How do you perform a hindlimb flexion test?
DISTAL LIMB: same as forelimb
PROXIMAL LIMB: Spavin test –> 90 sec (not hock specific)
In what direction should you give local anesthesia?
Begin distally and work proximally –> direct needle distally
What diagnostic tool allows you to look soft tissue and some bone real time?
Ultrasound
When is nuclear scintigraphy/ bone scan indicated?
- Can’t determine site of lameness
- Lameness not detected with US or radiographs
- Multiple limb lameness
- Intermittent lameness
- Upper limb/ pelvic lameness
- Possible fracture not seen on rads
– Gives poor anatomic detail
don’t use in young horses –> active physis
What is a side-effect of nuclear scintigraphy?
- Horse will be radioactive
What diagnostic tool is great for soft tissue unable to be seen with US?
MRI
- Better for soft tissue and fluid contrast
- Used for lameness diagnosis that can’t be made with other diagnostics
What is an Equinosis Q/ Lameness Locator
- Uses wireless, body-mounted sensors to detect lameness
