A femoral head and neck ostectomy (FHO) is a surgical procedure that is performed in pets to eliminate hip joint pain that may be caused by any number of diseases. This pain is often the result of the loss of cartilage in the joint, which causes bone to rub against bone during movement.
In order to understand this procedure, it’s important to know a little about the anatomy of your pet’s leg. The femur is the longer bone in the leg and is equivalent to the same bone in the human thigh. Like the human leg, the top end of the femur has a ball, referred to as the head, which extends out on what is called the neck and fits into the hip socket. This ball and socket joint allows the leg to move in a circular motion instead of bending like a hinge, as in the human elbow joint.
The FHO procedure removes the femoral head. This results in the formation of a pain-free, functional "false joint.” Because the part of the femur rubbing on bone at the hip joint is removed, no bone-on-bone interaction is taking place. The removed bone is not replaced, forming a false joint because there is no longer a connection between the femur and the hip bones.
Whenever your pet is showing signs of a health issue your first step is to contact your primary care veterinarian. If it is indicated that your pet may suffer from hip pain or another serious condition, a veterinary specialist is available at an ExpertVet certified hospital.
A femoral head and neck ostectomy is a relatively inexpensive way to relieve hip pain. It is commonly performed in dogs and cats for severe degenerative joint disease or fractures involving the hip joint. The FHO is relatively quick and involves significantly less risk and expense than a hip replacement procedure because it does not involve the placement of implants. Because there is no longer a ball-and-socket joint connecting the femur to the hip socket, physical rehabilitation to develop the musculature around the hip is an important part of the procedure.
This generally means that your veterinarian will prescribe physical rehabilitation to help build up your pet’s strength before and after surgery. Muscle strength will help your pet maintain good walking form in the absence of a leg to hip joint.
The success of FHO surgery depends on your pet’s ability to develop this "false joint." This is directly related to several factors, including the weight of the patient, the existing muscle mass around the hip prior to surgery, the patient’s activity level, and physical rehabilitation. As your pet’s greatest advocate, it is to his advantage for you to gain the most information about how to help your pet strengthen key muscles to allow your pet to have the best outcome possible following this surgery.
Small dogs and cats routinely experience no gait abnormality (lameness) or pain following a FHO. This is because it is easier for the body to support and maintain a false joint when the leg affected weighs less and in turn, is less of a burden on the body. Larger dogs – those greater than 50 pounds – also experience pain relief but require more aggressive rehabilitation and more time to develop their "false joint.” This doesn’t mean that large dogs cannot do very well with this surgery. In any size patient, the reduction in pain should improve the quality of life. Patients of all sizes can achieve excellent results with rehabilitation, specifically in a water treadmill under the supervision of a trained veterinarian.