When multiple graded stakes-winning gelding Green Mask shattered both sesamoid bones in his left front fetlock during a workout in 2017, owner Abdullah Saeed Alamaddah and trainer Brad Cox knew that immediate care was needed for the fracture. The gelding was sent to the University of Pennsylvania's New Bolton Center for surgical fusion to stabilize the joint. The surgery, performed by Dr. Dean Richardson, was a success. For many racing fans, that's where the story ended – with a large amount of hardware holding everything together. By July 2018, however, Green Mask underwent a second surgery, this time to remove the plate and screws used to heal the fracture.
Though many of us watching from afar may not realize it, it's not uncommon for surgeons to go back in and remove the metal that was so crucial at the start of healing.
Depending on the type of fracture and the location, fractures are most commonly stabilized with stainless steel screws or plates and screws. Casts or splints, wires, cables, and other items are often used in combination. For Green Mask, Dr. Richardson used a locking plate that was placed down the front of the joint and a tension band cable that measured 1.7 millimeters in diameter placed behind the fetlock. Screws were inserted across the joint in the sesamoids to encourage fusion of the joint.
Surgeries requiring the use of plates and screws are carefully planned, with the first goal being preserving as much of the soft tissue around the area of the fracture as possible to keep the maintenance of the blood supply and to allow for faster healing. Plates are applied to the surface of the bone.
Dr. Richardson uses a combination of top-of-the-line technology and skills to repair every fracture. The use of computed tomography (CT) scans during orthopedic surgery allows surgeons to see the bone, blood vessels and soft tissues to accurately place screws and plates with minimum issues. The use of CT scans lets the surgeon plan and complete accurate reconstruction of fractures and proper alignment of joint surfaces to reduce the chance of arthritis developing and increase the chance of a return to full athletic function. In an injury like that of Green Mask, the goal is comfortable retirement.
With major surgeries such as this, the risk of infection is always a concern. Green Mask's injury was significant and involved soft tissue trauma at the same time as the sesamoid fractures. The time and surgical exposure required for the surgery and, most of all, the need for so much metal in the limb to provide stability all increase the risk that bacteria will get into the leg. Any foreign material such as stainless steel provides a surface for bacteria to survive in what is termed a biofilm. Infection associated with a biofilm on plates and bone screws will be difficult to control and can lead to delayed or failed fracture healing.
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Support our journalism while accessing bonus behind-the-scenes content, Q&As, and more. Subscribe to our Patreon stream.There are two reasons why surgeons would perform surgery to first insert stainless steel plates and screws into a fracture and then to remove said plates and screws.
“It depends entirely on the nature of the original injury and the purpose of the horse at the time you're making the decision,” Richardson said.
In simpler cases than Green Mask's, such as a medial condylar of a cannon bone fracture, surgeons use a combination of screws and one steel plate, with the plan to remove the plate after three months.
“The reason you're removing the plate in this case is because the expectation is for that horse to go back and race,” Richardson said. “A horse isn't likely to race well with a large metal plate still on the cannon bone.”
Richardson explained that this is the same case in human athletes—if a plate is used in an area of the human that does a lot of bending, surgeons will remove that plate once the fracture is healed, and the athlete trains to continue activities.
Another case of inserting and removing hardware to repair an injury can be seen in the extended career of 2011 Kentucky Derby winner Animal Kingdom. After Animal Kingdom stumbled in the Belmont Stakes, fracturing his hock, Richardson performed surgery to repair the hock, by using screws to repair the fracture in the right place. The surgery was a success, with Animal Kingdom going on to win the $10 million Dubai World Cup in 2012.
However, there are times when a plate is a permanent fixture on a horse, and that's when the plate is located in an area that doesn't bend a lot. For example, plates involved with repairing a fracture in the ulna (elbow) can be kept in and the horse can return to the track.
“Most of the time, a plate in that location isn't going to cause a problem to a racehorse,” said Dr. Richardson. “However, in other places they will cause issues.
“Clearly that one set of circumstances where the plate is being removed is the planned goal, so you're keeping that in mind from the time you fix the fracture. You would virtually never do that in a horse unless they're going back to being an athlete. If you're putting a plate in and the horse is going to retire to be a broodmare, breeding stallion or pasture horse, we never remove the plates… with one exception.”
That one exception is when there is an infection that is localized to the inserted plate, which is what happened to Green Mask. Once bacteria have formed the biofilm on the steel, and infection occurs at the site of the plate. Systemic antibiotics don't often help, and infections such as these are rarely cured unless the metal is fully removed. In the case of Green Mask, his fracture had fully healed by the time the infection appeared, so it was safe to remove the plate.
“More than 90 percent of the time, if you have a fully healed fracture, or healed joint fusion (arthrodesis), and an infection is present, you go ahead and remove the metal,” says Dr. Richardson. “In nearly all cases, removing the infected metal will result in elimination of the horse's infection and that horse can go the remainder of his lifespan with any further related problems. Just as is true in human fracture repair and joint replacements, infection is the most single most important complication. Fortunately, the rates for this complication continue to decrease.”
The removal of the plate was a success for Green Mask, who later returned to his retirement home at Old Friends in Georgetown, Ky. The only sign of the initial fracture is the mechanical lameness present at the walk and trot. His fetlock is fused, which means it doesn't bend the way a normal joint would, resulting in a hitch in his step, but the joint is free of any signs of infection.
“He's seen as 'lame' because his movement is asymmetrical, but lameness and pain are not the same thing,” Richardson said.
Four years later, Green Mask is enjoying life in a paddock along the regular tour route at Old Friends. He will soon gain a new neighbor with the anticipated arrival of fan favorite Lava Man.
The post A Tale Of The Two Surgeries That Brought Green Mask From Catastrophe To Happy Retirement appeared first on Horse Racing News | Paulick Report.
