• Body Condition Score (BCS) and Muscle Condition Score (MCS)
• Pain Score
• Clinical Metrology Instruments (CMIs) 

 

Body Condition Score and Muscle Condition Score

Body Condition Score (BCS) and Muscle Condition Score (MCS) are two subjective assessments which add value both to the initial assessment of lame and osteoarthritic patients, but also to owner education and ongoing management.

BCS is a method used to assess a dog’s overall health and body fat levels, while the MCS is a method used to evaluate a dog’s muscle mass, which is crucial for assessing their overall health. MCS focuses on muscle condition rather than just body fat, as muscle loss can occur even in dogs with normal body weight.

The WSAVA and other groups have produced visuals which can be used for team education, but also for the owner education important to make meaningful impact and improve the likelihood of successful dietary management in particular.

These resources are freely available for download via links below:

Body Condition Score:

• Dog Body Condition Score
• Cat Body Condition Score

 

Muscle Condition Score:

• Dog Muscle Condition Score
• Cat Muscle Condition Score

 

Recognise pain and its expression in different species

As has been mentioned at the start of this section, dogs and cats can often show pain in different ways, this underpinned by their differing normal behaviours, fears and motivations.

Another important factor is the differing age of patients and how this may affect the symptoms of pain.  Young animals may not demonstrate the classical signs of pain as readily as the older animal who has lost many of the compensatory mechanisms which can act to disguise pain. However, older animals suffering from pain showing clinical signs may be dismissed as ‘just getting old’.  Pain assessment is subjective as the pain experience is unique to each individual, and the signs may be very difficult to judge as it is often manifested as changes in normal behaviour.  These are most obvious to the pet owner.

The development of various pain scales and clinical metrology instruments help greatly in not only measuring the response to treatment but also in identifying animals who are in pain as a result of the disease and need help.

 

Screening and Assessment Tools (Clinical Metrology Instruments) for OA diagnosis

Dogs

Several clinical metrology instruments (CMI) have been developed to evaluate musculoskeletal pain and assess the response and outcome to management. 

These include the Canine Brief Pain Inventory (CBPI), Liverpool Osteoarthritis in Dogs (LOAD), Canine Orthopaedic Index (COI) and Hudson Visual Analogue Scale (HVAS). These questionnaires aim to produce a reliable and repeatable means of assessing the status of patients.

Studies have been performed to validate these CMIs as being a reliable and repeatable means of assessing pain and outcome, and also to assess their accuracy relative to means of objectively assessing lameness, as well as their validity relative to each other (Alves, et al., 2022) (Innes JF, et al. 2023).

Cats:

Similar CMIs are available for the assessment and ongoing review of feline degenerative joint disease (DJD)-associated pain. One being the feline musculoskeletal pain index (FMPI) Benito J, et al. 2013) and the Montreal Instrument for Cat Arthritis Testing (Klinck MP, et al., 2017).

Osteoarthritic Screening Questionnaires:

While the CMIs detailed above can be used for assessment and status review of osteoarthritic patients, there are also simple screening questionnaires that can be of significant benefit to assess patients presenting in your clinic, either prior to standard consultations or as part of senior pet clinics.

These, often single-sided questionnaires, are quick, easy to use and have been validated to prove their value in picking up osteoarthritic change and musculoskeletal pain, prompting further assessment and specific assessment.  

Dog Screening Questionnaire:

One such dog screening questionnaire, in which ≥1 positive response (ticking a box titled “Yes”) was used to prompt further examination and assessment of patients with previously undiagnosed osteoarthritis, later confirmed by a vet as occurring in 38% of dogs (188 of 500) is available here and below:

Table 3: Dog Health Questionnaire, from Wright, A. et al., 2022. Note – removing questions 7-9 (in red above), which are historical, doubled specificity to 71%.

Question	Yes/No
1. Does your dog limp or appear stiff after exercise?	Yes □ No: □
2. Do you think your dog shows signs of pain?	Yes □ No: □
3. Is your dog reluctant to climb stairs or jump?	Yes □ No: □
4. Does your dog have difficulty in rising from a resting position?	Yes □ No: □
5. Have you noticed a change in your dog’s behaviour?	Yes □ No: □
6. Does your dog tire easily or lag behind during walks?	Yes □ No: □
7. Has your dog ever been injured?	Yes □ No: □
8. Have you ever given your dog medication for pain?	Yes □ No: □
9. Has your dog gained weight in the last year?	Yes □ No: □

 

Cat Screening:

OA screening questionnaires are also available for cats, developed with the aim of being a rapid means to identify cats likely to have degenerative joint disease (DJD) associated pain.

With potentially as few as 6 questions, the questionnaire below has been shown to be effective at identifying DJD. In non-informed owners (pets not yet diagnosed as having MSK pain) the questionnaire showed sensitivity and specificity as being 55% and 97%, respectively.

Link to the study behind this questionnaire is available here and resulting in materials for use in the consulting room, click here:

“To determine if you pet is showing signs of DJD-associated pain, please complete the following questionnaire.

Please answer all questions:

Question	Yes/No
Climbing up stairs: uses ‘bunny-hop’, with both back legs hopping at same time, and/or stops for a break	Yes □ No: □
Climbing down stairs: angles body to the side, descends one stair at a time, and/or stops for a break	Yes □ No: □
Chasing Moving Objects: slows down or takes breaks during play and/or may have thinner frame near the tail	Yes □ No: □
Jumping Up: hesitates before jumping up, doesn’t clear jumps in one leap, and/or uses arms to pull the legs up	Yes □ No: □
Jumping Down: hesitates before jumping down, makes smaller jumps vs. one big one and/or reaches down towards the group instead of leaping	Yes □ No: □
Running: moves at a slower speed  and alternates between jogging  & walking, and/or back feet  angle together	Yes □ No: □

 

Table 4: Proposed Feline Musculoskeletal Pain Screening Checklist (Feline MiPSC). DJD = degenerative joint disease, from Enomoto M, et al., 2020.

Assessing the OA Measurables

We do have many means of measuring the changes associated with osteoarthritis. These add value at the time of initial assessment, and more importantly should be updated at the time of further review. This enabling us to update status and review patient’s progress – in light of our treatment plan.

It is vital however to understand the advantages and weaknesses of all tools used to assess OA care and in this section we will focus on whether assessments are objective or subjective. 

• Objective: Objective assessments aim to remove personal bias and judgment from the evaluation process. They rely on standardised, measurable criteria to determine the outcome. Think of a multiple-choice test or a blood pressure reading. The result is what it is, regardless of who is conducting the assessment.

 

• Subjective: Subjective assessments, in contrast, involve the evaluator’s (vet or owner) personal judgment and interpretation. These assessments often rely on qualitative data and require the assessor to make nuanced decisions based on their feelings, expertise and experience. Examples include lameness scoring or visually assessing weight bearing.  

 

Key Point: while some ‘measurables’ might seem binary, such as those with a yes or no answer, the test may still be subjective – this applies to the CMIs mentioned below.

Labouring the importance of this understanding is important. If we are going to attribute ‘value’ to our management of OA we need to understand how best to assess the measurables, and be proportionate in attributing validity to their results. 

Summary

Visual and physical (clinical, orthopaedic, neurological) examination along with the tools and techniques outlined in this module can help to screen and identify many osteoarthritic patients who present to us in our consulting room. 

Due to the frequency of OA, there is a great opportunity to further refine our use of tools such as CMIs, as well as our visual and physical diagnostic skills. With practice you will notice milder lameness visually and start to detect more subtle changes in range of motion or joint shape on orthopaedic examination.  

Standardising your assessment, making it purposefully repeatable, will accelerate this learning.  

While radiography may not seem essential for every diagnosis of OA, it is important to maintain an open, indeed inquisitive mind. If you do make a clinical diagnosis of OA and the patient does not respond as anticipated or they develop other symptoms; take a step back, start fresh and make full use of radiographic and other diagnostics to ensure your diagnosis is accurate.