An average horse weighs about 1,200 pounds. Rose Hardy is a mini horse who tips the scales at just 253 pounds. Her tiny size not only makes her cute, it may have saved her life.
Just like dogs and humans, horses have hip joints that consist of a ball (at the end of the femur bone) and socket, held together by strong ligaments and muscles. When those ligaments and muscles are injured or diseased, the ball can fall out of the socket and the joint becomes dislocated. It is very painful.
In a dislocated joint, the ruptured ligaments make it difficult to adjust the femur back into the correct position and keep it there (see illustration below). Often, surgical treatment is necessary. In a prodedure called a femoral head and neck ostectomy (FHO), the ball (or head) is removed from the end of the femur. Then scar tissue forms to create a new, false hip joint. This usually relieves pain and improves quality of life dramatically.
FHO surgery is most successful in small dogs, but has also proven worthwhile in larger breeds. Unfortunately, when a horse’s hip joint dislocates, FHO is not often successful because the altered joint cannot support the weight of a horse. Many times, the horse is euthanized.
In June, Roberta Hardy noticed that her mini horse, Rose, was lame and in obvious pain. She took Rose to Dr. Kirsten Mason, of Redwood Equine Veterinary Services, who took radiographs that revealed a dislocated right hip joint. Dr. Mason referred Rose to the OSU Veterinary Teaching Hospital for further evaluation. At the hospital, the equine team sedated Rose and tried to manually relocate her hip joint. As is often the case, the joint would not go back into the proper position. That was very sad news for the Hardy family, who have several mini horses that they love like pets.
The OSU Veterinary Teaching Hospital does dozens of FHO surgeries on dogs every year, but never on a horse. Because Rose is so tiny, the surgical team felt she was a good candidate for a successful FHO. Dr. Cate Hackett explained the surgery, prognosis, and long rehabilitation process to Roberta Hardy, who decided to give it a try.
The surgery went well and Reese Douglas, a fourth year veterinary student, was assigned to Rose’s case. “I was in charge of her daily care, which included preparation and giving of medications, daily physicals, walks, pain assessment, and feed preparation.” Pain management was a huge factor in Rose’s recovery so Douglas, under the supervision of surgical resident Dr. Elizabeth Collar, learned how to prepare IVs and place epidural catheters for pain medication.
Four days after surgery, Douglas was able to walk Rose out of her stall and back, several times a day. Five days after surgery, she walked Rose out the back door, and over to the north lawn so she could graze for five minutes. “She was a difficult patient to get to eat,” says Douglas. Rose turned her nose up at beet pulp and Equine Senior, so Douglas picked a pound of fresh grass every day to feed her.
One week post-surgery, Hardy took Rose home with extensive instructions for her rehabilitation, including a weight reduction diet to minimize stress on her new joint. Rose now walks for fifteen minutes, three times a day, and has been moved to a larger paddock. Her appetite has definitely improved. “Food is a good motivator to keep her moving. I walk her when the barn manager is feeding from the back of the Gator. She will eat a bit, then the gator moves forward and Rose follows it.”