#AskTheVet with Dr. Jonny Furlong

Question: What are the differences between all the various things you use for joint injections? 

Answer:

We have lots of choices for intra-articular therapy, which is great for our patients, but can be confusing for clients. 

Intra-articular corticosteroids, meaning steroids injected directly into a joint, have long been a mainstay for managing arthritis. These are potent ant-inflammatories, which provide immediate and relatively long lasting symptomatic relief. Typically we use these in combination with hyaluronate, which provides further anti-inflammatory effects. Chronic inflammation promotes the arthritic process, so reducing inflammation is an important aspect of managing joint disease.

Corticosteroids are very useful when used appropriately, but they’re not always the best choice. They effectively reduce inflammation, but take a bit of a shotgun approach to do so, which can also limit the healing response.

PRP (platelet rich plasma), IRAP (interleukin receptor antagonist protein), and Prostride are all somewhat similar products, where we draw the patient’s blood and harvest various components which can reduce inflammation and/or promote healing. These different treatments take different approaches to managing joint disease. 

IRAP takes a very targeted approach, amplifying an endogenous anti-inflammatory mediator, thereby reducing inflammation without any compromise to healing capacity. PRP takes a broader approach, where we concentrate platelets and inject those straight into the joint. Platelets are the first responders to injury throughout the body, capable of recruiting cells and releasing growth factors to facilitate healing. When we put them into joints, we trust them to direct the healing and anti-inflammatory responses appropriately. Prostride is essentially a combined approach, with a mix of platelets and some amplification of target mediators.

A relatively newer class of drugs is polyacrylamide gel, which you may have heard of by their brand names, such as Arthramid or Noltrex. These treat joint disease in yet another manner, binding with the synovium (the lining of the joint), and thereby altering the function of that tissue. Research is pretty limited on these, but the early results have been promising.

When choosing which product to use for your horse, we take many factors into consideration, including: clinical exam, diagnostic imaging findings, patient’s age and metabolic status, treatment history, intended use, upcoming competitions and associated drug rules, costs, and risk of side effects.