PEOPLE vary in their appetite for risk, their acceptance of hazards and how they deal with them when they inevitably happen. There are known risks associated with injecting equine joints and I’ve had my fair share occur over the years. To my mind the important factors can be grouped under headings such as: what is injected, how it is injected, by whom, where it is injected and into what kind of horse.

Most commonly the substance is a pain-relieving/anti-inflammatory agent such as a local anaesthetic or cortico-steroid, or alternately a joint-nourishing agent such as hyaluronic acid (changing the engine oil so to speak!):

  • ‘Local’ is mostly used in the diagnosis of the source of pain in a lame horse viz. ‘joint blocks’.
  • ‘Cortisone’ in the dampening down of inflammation – perfectly legitimate in the older arthritic equine. The most significant risk, to my mind, comes with repeated doses into the same joint in young horses when exercise is loaded on top. Some corticosteroids are more to blame than others but this practice potentially weakens joint cartilage increasing the risk of further damage. I can still vividly remember the veterinarian at Suffolk Downs racetrack (where I once worked as a ‘hot-walker’) coming round the morning before racing to ‘medicate joints’. I hope we have moved on, in the interests of young athletes’ future careers.
  • Joint-nourishing agents come in many shapes and forms, often expensive. These can only do good of themselves, but a key issue (as with all injections) is not to introduce infection.

    • Which brings us to the ‘how’ – a sterile technique is vital as is the ability to perform the procedure safely. Some of these come with ‘basic’ veterinary training, some with experience gained over time. Infection is a constant concern and some vets sometimes include small doses of antibiotic into the cocktail being infused. This however is no substitute for asepsis (a condition in which no living disease-causing microorganisms are present), effective restraint and good technique. But risks, hopefully seldom, do come to pass. I’ve had to return to a horse and flush a joint free of infection post injection; I once had to anaesthetise a pony to retrieve the shaft of a needle broken off at the hub and now embedded under the coronary band. Ouch!

    It shouldn’t need saying but here goes – these are veterinary procedures so leave them to vets!

    A thorough knowledge of the location and characteristics of relevant structures (anatomy) is the basis for all good surgery and I include joint injections here. The vet often has limited points of access to a particular joint so choosing the correct spot and equipment (e.g. needle size) are key to success. Nearby hazards can include other joints and tendon sheaths in a complicated area like the carpus (knee), blood vessels (almost everywhere!) and impenetrably dense ligaments, perhaps the pelvis or neck region. The drug won’t work in the joint unless its properly deposited there!

    Under ‘what kind of horse’ I would consider issues such as the animal’s use or job:

  • Is he competing under rules (racing or FEI)? In which case the substance injected, the amount and timing in relation to competition are critical items to consider. The authorities publish ‘clearance times’ for some commonly used substances; vets have to then calculate ‘withdrawal times’; this is not an exact science.
  • Is he being asked to land at speed on tender coffin joints or perform intricate dressage movements on dodgy hocks?
  • Consider also his future use – are you doing harm to a future career by having joints injected for short-term gain; would a period of rest and rehab plus supportive joint therapy be better in the long run?

    • Joint injections certainly have their place in the diagnosis and management of disease but like many veterinary procedures they are not without real as well as potential hazard to the patient. The former should be minimised by careful consideration of the factors outlined here; the latter shouldn’t but inevitably sometimes come to pass.