Equine Lameness

Lameness exam interpretation

LAMENESS EXAMINATIONS CHEAT SHEET

Lameness grades (AAEP)

  • Grade 5: non-weight bearing
  • Grade 4: lame at a walk
  • Grade 3: lame at a trot
  • Grade 2: lame consistently under special circumstances (eg lunging)
  • Grade 1: lameness difficult to observe and inconsistent, irregardless of circumstances

Straight line lameness exam

Foreleg lameness : HEAD NOD

  • “Down” on the “sound”
    • The horse throws his weight to his hind limbs when he has to step on the sore leg
    • This is the equivalent of “up” on the “lame” leg.
    • Forelimb lameness is more challenging when the problem is bilateral, such as with navicular syndrome. The horse can’t decide which leg to bear more weight on and instead shows a short choppy gait.
    • Sometimes it is easier to hear the lameness better than to see it (change in force of landing)

Hind limb lameness : HIP “HIKE”

  • More hip motion, either up or down, on the lame leg
    • not necessarily a hike
    • occasionally will lead to a mild head nod ( the horse usually keeps his/her head higher overall – no deep nod)

Lunging

  • Used to exacerbate lameness (jog in a tight circle)
  • In most instances, the lame leg will be worse when on the inside of the circle
  • If it is more lame when the leg is on the outside of the circle, think soft tissue (pulled more)

Flexion tests

  • Used to exacerbate lameness; generally signifies joint pain; can be soft tissue if pulled when limb flexed
  • Distal limb flexion : flexes fetlock, pastern and coffin joint
  • Carpal flexion : flexes carpus only
  • Spavin test : flexes hock, stifle and hip
  • Upper limb flexion, forelimb : flexes elbow or shoulder; extends other joint

Passive Lameness Exam

Palpation

  • Check for asymmetry, swellings, and pain in response to palpation.
  • Horses with forelimb lameness will often be sore in the shoulder region even if foot pain due to abnormal carriage of the limb
  • Similarly, horses with hindlimb lameness will often have back pain

Hoof testers : around white line ; from frog to walls and across bulbs of heel

Check hoof -pastern axis and hoof balance (coronary band parallel to the ground)

Churchill hock test : tests for pain in the lower hock joints (bone spavin)

Done by trying to pull the medial splint bone around to the lateral side of the leg. If painful, horse will react by abducting the leg (not positive if he pulls back or forward; has to pull away from the source of pain on the medial aspect of the leg)

Range of motion (ROM) : amount of flexibility in joint. E.g. should be able to flex carpus so that heel touches elbow; if can’t, this is restricted ROM

Local anesthesia

Used to numb an area to determine if pain is coming from that region. Generally start low and work up

Common causes

In the forelimb, the source of the majority of the lameness is in the foot. In the hindlimb, the source of the majority of the lameness is in the hock. This does vary by age and performance.

Foot pain will often cause the horse to overstress the shoulder due to changes in how the limb is advanced. Hock pain will often lead to secondary back pain as the horse tries to protect the limb.

License

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Large Animal Surgery - Supplemental Notes by Erin Malone, DVM, PhD; Elaine Norton, DVM PhD; Erica Dobbs, DVM; and Ashley Ezzo, DVM is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License, except where otherwise noted.