Diagnosing degenerative joint disease

Degenerative joint disease (DJD) is the most common cause of lameness in horses, and recent estimates indicate up to 60% of lameness-related problems in horses are related to DJD.1 Physical and lameness examination along with diagnostic tests are most commonly used to diagnose DJD. Each veterinarian has a specific system for performing lameness exams, depending on the specific patient and reasons for the evaluation.

Adequan Equine veterinarian examining horse img

A grading system to support communication and health records

Evaluating lameness can be very challenging because each horse has unique characteristics and lameness can appear in such a wide variety of ways – from a subtle change in gait or to complete inability to bear weight on an affected limb. This is why the American Association of Equine Practitioners (AAEP) developed the following scale.

AAEP Lameness Scale2


Lameness not perceptible under any circumstances.


Lameness is difficult to observe and is not consistently apparent, regardless of circumstances (e.g. under saddle, circling, inclines, hard surface, etc.).


Lameness is difficult to observe at a walk or when trotting in a straight line but consistently apparent under certain circumstances (e.g. weight-carrying, circling, inclines, hard surface, etc.).


Lameness is consistently observable at a trot under all circumstances.


Lameness is obvious at a walk.


Lameness produces minimal weight bearing in motion and/or at rest or a complete inability to move

A treatment option for DJD

If your horse is diagnosed with degenerative joint disease, your veterinarian will recommend a therapeutic approach that may include treatment with Adequan® I.M. (polysulfated glycosaminoglycan), the only PSGAG available that’s proven to proactively treat the disease and not just the signs of DJD.3

Adequan Bottles

How is canine osteoarthritis diagnosed?

Adequan® I.M. brand of polysulfated glycosaminoglycan (PSGAG)
Adequan® I.M. is recommended for the treatment of non-infectious degenerative and/or traumatic joint dysfunction and associated lameness in horses.
Adequan® I.M. is for veterinary use only. The prescribing information contains complete use information which includes dosing, contraindications, warnings and cautions. Always read, understand and follow label and use directions. PLEASE CONSULT the Full Prescribing Information.
1. McIlwraith CW, Frisbie DD, Kawcak CE, van Weeren PR. Joint Disease in the Horse. St. Louis, MO: Elsevier, 2016; 33-48.
2. Lameness Exams: Evaluating the Lame Horse, American Association of Equine Practitioners, https://aaep.org/horsehealth/lameness-exams-evaluating-lame-horse. Accessed October 21, 2019.
3. Adequan® I.M. Prescribing Information, Rev 03/2021C.
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