Signalment

As well as taking the history, carefully considering the patient’s signalment is another fundamental that contributes to the ‘most likely’ diagnoses and the likelihood of OA changes being present, indeed often in specific locations, in our patients.

Assumptive diagnoses, such as the Labrador with forelimb lameness being lame due to sore elbows or older spaniels with thickened toes being lame only due to their toes is the wrong approach. It is still wise however to hone skills for developing an understanding of common ‘signalment’ OA. This ability will grow as your confidence and ability of diagnosing OA develops, through a standardised diagnostic approach.

Taking History

When suspecting OA, or investigating other lameness there are some text-book questions to ask. 

What is important is not to be drawn to the ‘obvious’. This along with over-interpreting signalment is that you miss the concurrent lameness or co-morbidities, which can both also impact on successful management.

Key Point:  do not over-focus on the ‘obvious’. Take a full history and spend time observing patients. Many OA patients will have co-morbidities, medical issues and multiple causes of lameness: all important for successful management

Common questions when taking history include:

• Are there any pre-existing conditions they are on medications for?
• If so what medications and when were they last given?
• Have they been on any previous medications that ‘disagreed with them’?
• If so, what did they cause and can you remember their name?
• How long has the owner had the dog?
• Are they fully vaccinated?
• Have they ever left the UK or were they adopted from/imported from outside the UK? Are owners uncertain?

Key Point: with the increasing concerns of Brucella Canis many practices will already have standardised approaches for every new pet registration. These will ask about import status and testing for B. Canis. 

One symptom of B. Canis can be lameness/joint pain and the author would strongly advise that if any history of importation/travel, B. canis SAT and iELISA serological tests should be performed at APHA itself. Not in practice tests.

Further info and BVA, BSAVA, SPVS, and BVNA policy position on Brucella canis is here.

• How long ago did the lameness seem to start, and what age was the dog at that time?
• Which limb(s) do they feel their pet is lame on? 
• Does the owner feel it is a particular leg and what signs does the owner see?
• Was the onset of lameness sudden (acute) or gradual in onset?
• If the lameness was acute in onset, does the owner remember a potentially inciting event/cause?
• Does the severity or appearance of the lameness vary?
• If so, does the severity vary in response to rest, exercise or administration of drugs such as NSAIDs or any other factor?
• Has the dog previously had any treatment for the lameness? If so, what? Did it work?

Although signalment and a thorough history will not identify the specific cause of a patient’s lameness, both help to frame the clinical decision and diagnostic decision making following the general and orthopaedic examination.