Approach to the Lame Horse

Question 1

What methods would you use to approach lameness in a horse?

Answer 1

History (Anamnesis - info from owners) - Breed, age, Sex, Use
Observation from distance - Symmetry, posture, conformation
Observation of gait/movement -baseline, additional tests)
Palpation (inclu hoof testers)
Selected examination (manipulation of joints (RoM), flexion tests)
Diagnostic analgesia
Diagnostic Imaging
Treatment
(Nerve and joint blocks)

Question 2

What questions would you ask about the current episode of lameness?

Answer 2

History of trauma
Duration 
Deterioration or improvement
Effects of exercise
Any management changes - shoeing, flooring, bedding, health/diet, training, medication
(Past lameness issues?)

Question 3

What is a common lameness condition in older horses?

Answer 3

Chronic progressive osteoarthritis seen in many places:

• proximal interphalangeal joint (pastern - between P1 and P2)
• distal interphalangeal joint (coffin - between P2 and P3)
• Metacarpophalangeal joint (Fetlock - between cannon and P1)
• Carpometacarpal joint (between distal carpal bones and the proximal metacarpals)
• Coxofemoral joint (hip joint)
• Femorotibial joint (stifle joint)
• Tarsus
• Previous injury (retired racehorses)

Question 4

What factors do you look at when observing from a distance?

Answer 4

Symmetry - in muscle
Posture
Conformation

Question 5

What can you palpate to help your diagnosis of lameness?

Answer 5

Hoof testers- abscesses
Insertions (SDFT) + origins (suspensory ligament)
Joints - distension, temp, pain, R of motion, swelling, heat
Distal sesamoidean ligments
Digital pulses
Tendons - loaded and unloaded

Question 6

What can you palpate to test hindlimb lameness?

Answer 6

Back
Pelvis
-Tuber coxae (wings lateral side)
-Tuber ischii (caudal - just below tail base)

Question 7

What is limb movement composed of?

Answer 7

Horse’s TRAVEL and ACTION

Question 8

What is the definition of travel?

Answer 8

Flight of a single foot in comparison to the other limbs

• Arc of hoof flight
• view from the side/behind

Question 9

What is the definition of action?

Answer 9

Overall description of gait characteristics

• joint flexion, stride length, suspension and others
• varies between breeds

Question 10

What are the different phases of stride?

Answer 10

Landing
Stance - Loading phase
Breakover (Heel lift, toe pivot)
Swing

Question 11

What are the 4 different gaits?

Answer 11

Walk
Trot
Pace
Gallop

Question 12

What are the characteristics for ‘Walk’?

a) Suitable to see lameness?

Answer 12

Even rhythm - 4 beat gait
(each foot comes down by itself)
a) Not suitable to see subtle lameness

Question 13

What are the characteristics for ‘Pace’?

a) Suitable to see lameness?

Answer 13

2 beat lateral gait
Ipsilateral fore- and hindlimbs elevate together + and then alternate to contralateral side
a) Impure gait in most breeds - seen mainly in STB racehorses

Question 14

What are the characteristics for ‘Canter’?

a) Suitable to see lameness?

Answer 14

3 beat gait with lead preference
(Left leading - (RH—> then LH and RF —> LF ))

a) Difficult to see subtle lameness but useful to see back,rider, saddle associated problems

Question 15

What are the characteristics for ‘Trot’?

a) Suitable to see lameness?

Answer 15

2 beat diagonal gait
(Opposite fore and hind limbs land together and swing
a)Steadiest + most rhythmic gait in most horses
PREFERRED FOR LAMENESS EXAMINATION

Question 16

What questions would you ask to assess a case of lameness?

Answer 16

1. Which leg is lame?
2. How lame?
   -appreciate difference with diagnostic imaging
   Trot the horse

Goal: localise lesion for targeted diagnostic imaging/tx

Question 17

What 2 things can you see when recognizing lameness?

Answer 17

-Fetlock drop
usually more on opposite (sound) fore- or hind-limb
EXCEPTION: Tendon or Suspensory Ligament damage

-Changes in Limb flight
cranial and caudal phase of stride

Question 18

What is the subjective quantification of lameness?

Answer 18

Grade 0: Sound
Grade 2/10: Lameness hard to detect at walk or trot - not apparent
Grade 4/10: Lameness barely detectable at walk, easy to see at trot - consistently seen
Grade 6/10: Easily detectable lameness at walk
Grade 8/10: Hobbling at walk. Unable/unwilling to trot
Grade 10/10: Non weight-bearing

Question 19

What do you recognise mostly in Forelimb lameness?

Answer 19

-Head nod/ Head elevation
When the lame forelimb hits ground - reduce load
(head down opposite forelimb)

-Asymmetrical contraction pectoral mm

-Sound/Concussion
Harder landing on sound limb (louder)

Question 20

What do you recognise in Hindlimb lameness?

Answer 20

-Pelvic hike
Pelvis hiked up when lame limb on around
Pelvis hiked down when sound limb hits the ground

-Elevation tuber calcis

-Drifting
Horse move away from lame limb (hindlimb does not follow forelimb)
Lame limb goes under body, in between space of forelimbs

-Sound harsher when sound limb lands

Question 21

What other methods can you use to access lameness?

Answer 21

• Acceleration sensors
• Different surfaces - soft/hard
• Circle
• Different gaits - severe lameness/suspected facture = WALK
• Under saddle - owner and separate rider
• High-speed Treadmill - STB pacers, trotters