LA Lameness Exam Flashcards
Lameness
A clinical sign; manifestation of signs of inflammation, including pain, or mechanical defect that results in gait abnormality, characterized by limping
Baseline lameness
Gait abnormality recognized when horse is examined at a walk or trot in hand, before manipulative tests are used
Induced lameness
Lameness observed after manipulative tests
Lameness distribution
Forelimb > hindlimb
Center of gravity closer to forelimbs so 60/40 weight distribution
(but lameness will depend on job)
Lameness in a thoroughbred racehorse
Forelimb > hindlimb
Lameness in a standardbred racehorse
Hindlimb ~ forelimb (weight pulled back by cart)
Most common location of forelimb lameness
95% at the level or distal to carpus
Lameness scale
0 - not perceptible under any circumstances
1 - difficult to see, inconsistent regardless of circumstances
2 - difficult to see, consistent under stressed circumstances
3 - consistently observed at a trot in a straight line in hand with no stress test
4 - obvious at a walk
5 - minimal weight bearing
Components of lameness exam
History
Exam from a distance (conformation, symmetry, posture)
Palpation (weight bearing + no weight bearing)
Movement - baseline + potential manipulative tests
Selective manipulation
Flexion
Lunging
Riding/driving
Different surfaces
Other tests
Diagnostic analgesia
Imaging
Palpation
Palpate every structure
Feel digital pulses
Hoof test
Voluntary neck flex ions
Detect signs of inflammation (swelling, effusion)
Assessment of movement
Evaluate lameness on both hard + soft surface
Evaluate from front, back, side
Evaluate on straight line + in circles
Key observations in lameness exam
- Head /neck nod
- Pelvic hike/drop
- Shorting of cranial phase of stride
- Drifting (away from lame limb)
- Fetlock drop (overweight bearing in sound leg)
Stress test : flexion
Jog horse in straight line to get baseline
Hold limb flexed for a period of time —> have horse job again
Results highly variable by length of time, practictioner, patient cooperation, etc
Full limb vs upper/lower (separate in forelimb, harder in hind due to connectivity)
Localization of cause of lameness
Nerve/joint/tendon sheath blocks - systematically numb the leg
Mechanical lamenesses
Stringhalt (ingestion of a particular weed, idiopathic)
Upward fixation of patella
Fibrotic myopathy (fibrosis/calcification of semis)
Peroneus tertius injury
Neurological disease
Palmar / plantar digital nerve block
Vol - 1-2 cc, 25 g/3/4 in needle
Palpate later/medial palmar/plantar digital neuro vascular bundle
Place needle axial to collateral cartilage as low in foot as possible
Coffin joint block
Dorsal approach is vascular / well innervated —> will bleed
Bandage after injection
Blocked structures: coffin joint, navicular bursa (by diffusion)
