Head bob in canine lameness: which forelimb is lame
4-year-old Labrador Retriever with a one-week forelimb lameness. At the trot in a straight line on a hard surface, the head rises every time the right forelimb lands and drops when the left forelimb lands.
Which limb is most likely affected?
chevron_right Show answer and explanation
A. The left forelimb, because it coincides with the head dropping
This is the classic mistake. The head drops when the sound limb lands, as it takes the weight the dog removes from the painful one.
B. The right forelimb
Correct. When the painful limb lands the dog lifts its head to shift weight caudally and offload it; when the sound limb lands the head drops ("down on sound").
C. A hindlimb, because a head bob is typical of hindlimb lameness
The head bob is the main sign of forelimb lameness. In hindlimb lameness the characteristic sign is the hip hike on the affected side during weight bearing.
D. It cannot be determined without radiographs of both limbs
Gait observation localises the limb before any imaging; radiographing without first localising the problem leads to irrelevant findings.
lightbulb Key takeaway
Observe at the trot, in a straight line, on a hard surface and from the front, behind and the side: the walk may hide mild lameness. In hindlimb lameness, the tuber coxae on the affected side rises during weight bearing. A severe hindlimb lameness can cause a misleading head bob, so always assess all four limbs.
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Updated: October 31, 2026 · Educational content for veterinary professionals. It does not replace current clinical guidelines or the judgement of the attending veterinarian.