Meet Maloo a lovely Standardbred yearling gelding who sustained an injury to his right knee in May 2016.                   Maloo was seen for a non-weight bearing lameness that presented with a large swelling and evidence of an old injury over his knee joint (carpus). He had not been obviously lame previously because the joint was draining and open and once the joint capsule closed (around 3 weeks later!) the infection was locked in the joint. This resulted in excessive fluid and cellular production within the joint, which became severely swollen and painful. Due to the worry of a possible joint infection, Maloo was immediately transported to the clinic for further investigation.

At the clinic we “tapped” the joint. This is where we insert a needle into the joint to obtain a sample of the fluid inside. This involves placing a needle into the suspected structure and taking a sample of the fluid. The samples were found to be consistent with an infection within the joint. X-rays revealed a small chip of bone fragment within the joint, suspected to have been caused by a sharp hard penetrating object such as wire or possibly a nail. Due to the length of time that there had been an infection in the joint, and due to the bone damage also we were very worried about Maloo and his prognosis was only around 50% of making it through without a life-threatening lameness.

In surgery, Darren removed the bone fragment visualising the joint by a camera under keyhole surgery and large volumes of sterile fluid were flushed through the joint to remove the infection and debris. Because the synovial structure (inside the joint) could actually be seen, debris could be physically removed, along with infected and damaged synovial lining. The joint was very angry with lots of debris and damaged synovial lining due to the chronic (3 week) infection, which all had to be cleaned up as could harbour any infection and re-infect the joint after surgery was completed.

We were all nervous over the next few days as we monitored Maloo for return of infection via repeat joint taps to check that the levels of infection cells were reducing. His lameness improved significantly over the next two weeks and we were pleased to see his joint taps showed his joint fluid cell numbers and protein were returning to normal levels. The team here at AHEC wish him all the best for his future!

We thank Maloo’s owner for letting us post this story as this is an example of how dangerous a wound over a joint can be. Many of you will have noticed wounds over synovial structures (joints/tendon sheaths/bursae) previously but as the horse has not been lame you have just monitored. This may be fine the majority of the time but you could be very unlucky here like Maloo and there can be serious consequences.


It cannot be reiterated too many times how serious synovial infection in a horse is. The chances of successful treatment though can be improved by undertaking the following advice:

Call the vet sooner rather than later
If your horse has a small wound but is very lame, CALL THE VET!
If the wound is over a tendon sheath or joint, CALL THE VET!
If your horse has stood on a nail and there is a foot penetration, CALL THE VET!
Early recognition and prompt treatment of synovial infection will dramatically improve the chances of a successful outcome.

2. Be aggressive in your treatment choice

Aggressive treatment early on in the disease process results in much higher success rates.