Page 120 - WSAVA2018
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 25-28 September, 2018 | Singapore
Signs of an orthopedic problem may include some or all of the following:
· stiffness on rising after rest
· change in exercise capacity or exercise behaviour
· change in stance (altered distribution of weight)
· lameness / change in gait
· pain – pain is the most common cause of lameness. Lameness can also result less commonly from me- chanical causes (such as patella luxation), neurologic disease, vascular disease, and systemic disease.
· change in normal shape
· asymmetry – for example joint enlargement or mus- cle wasting. Reduction in muscle mass is typically seen in chronic lameness.
· change in normal alignment
· change in stability or range of motion
It is important to recognise that quadrupeds are very good at “masking” lameness or not showing obvious limping until their pain is quite marked. This has both evolutionary and practical benefits. Close observation
of how an animal stands, moves, and gets up and down from a recumbent position will often indicate lameness in earlier or less severe cases.
What is lameness? Lameness is an abnormal gait or stance resulting from some abnormality in the locomotor system.
What are you trying to achieve in an orthopedic examination?
1. localize the limb(s) affectedis the animal lame and if so in which limb(s)?
2. localize the site(s) of the lameness where is the source of the lameness?
3. identify the cause(s) of the lamenessthis usually involves radiography, advanced imaging or other diagnostics
4. determine the appropriate treatment and prognosis
Some definitions that are useful when talking about
lameness:
· Stride - the full cycle of limb advancement
· Contact phase - the part of the stride when the foot is in contact with the ground
· Swing phase - the part of the stride when the foot is in the air and not in contact with the ground
There are 4 steps in an orthopedic examination
1. History
2. Observation of stance and observation of gait
3. Standing symmetrical examination followed by recumbent examination
4. Further diagnostics – as indicated
1. History
The history should be taken from the owner while the dog is allowed to stand or walk around in the consulting room or outside rather than placing the dog on the examination table. Having the dog walk or stand lets them become familiar and “more trusting” in unusual surroundings and allows you to observe them during this time.
In many cases simply by the way they stand or in some cases sit you will be able to identify the lame limb(s).
2. Observation of stance and observation of gait Observation of stance: simpler than gait observation Observing an animal stand often is sufficient to identify lameness and, in many instances, gives more useful information than gait exam.
Quadrupeds have the ability to shift their centre of mass both to one side, as with humans, and also cranially or caudally. This re-distribution of their mass reduces the load going through the lame / sore limb(s) thereby reducing the pain and very often minimises the observable lameness.
Visual observation of canine lameness is relatively insensitive. In one study 75% of dogs with no observable lameness were actually lame when measured objectively on a force plate1. In other words, even in dogs with significant unilateral lameness (and remember that bilateral lameness is even more difficult to detect
than unilateral lameness) only 25% showed apparent lameness on visual examination of their gait.
However even though quadrupeds shift their centre
of mass to minimise observable lameness, this shift is usually readily apparent provided that you are familiar with normal stance of dogs – and that you actively look for this change.
To expend the least amount of energy when standing a normal dog will stand with the foot directly beneath the dependent joint – the shoulder or hip joint. When dogs have a unilateral limb lameness they bend their spine laterally towards the lame side and bring their sound leg closer to the midline. The lame leg is laterally abducted. This creates a “tripod” stance where the lame limb is used for balance but is not taking full weight.
In some cases when you look at their feet you will see that in the sound limb that is taking most of the load the metacarpal / metatarsal pad is fully compressed and the nail tips consequently sit up off the ground. On the contralateral lame limb the pad is not fully compressed and so the nails are usually in contact with the ground.
When dogs have a bilateral forelimb lameness they often
43RD WORLD SMALL ANIMAL VETERINARY ASSOCIATION CONGRESS AND 9TH FASAVA CONGRESS
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