At first, a femoral head and neck excision sounds like something straight out of a Mediaeval executioner’s book. But the procedure known as an FHNE is actually a well-recognised surgical treatment for certain conditions affecting the pelvis and hind legs of dogs and cats. Although not a common operation, if you’ve been told that your dog may require one, it can help to understand what is being done and why.
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Some basic anatomy
The bones in the hind legs of a dog are the same as the bones in our legs, just different sizes and proportions. The bone in the top of the leg is the femur. The very top of the femur is a ball-shape, known as the femoral head. And it is this that fits into the socket of the pelvic bone to form the hip joint. Just like in people, this ball-and-socket hip joint can rotate in different directions to allow for a wide range of motion of the hind legs. Just below the head of the femur, the bone narrows slightly – known as the ‘neck’ – before widening again into the long shaft of the femur.
What is a femoral head and neck excision?
At first glance, a femoral head and neck excision appears to be a fairly unsophisticated operation; simply cutting off (excising) the head and neck of the femur. However, the procedure actually requires a lot of planning and measuring to ensure the cut is made in just the right place and at just the right angle; without compromising any of the vital soft tissues, nerves and blood vessels in and around that area.
But why??
So why would we need to go to such seemingly brutal lengths as cutting off part of the biggest and strongest bone in the body? The main aim of a FHNE is to relieve pain for the animal. For conditions such as arthritis of the hip joint, hip dysplasia, hip dislocations, hip fractures and Legg Perthe’s disease (where there is a loss of blood supply to the femoral head meaning the bone starts to disintegrate), a femoral head and neck excision can be a hugely beneficial option for treatment, and also relatively cheap when compared to surgery like a total hip replacement. For some of these conditions, like hip dislocations and hip fractures, a femoral head and neck excision is usually a last resort when other treatment options are not possible for whatever reason.
But can my dog live without a hip?
Yes, absolutely. As the area heals, the surrounding muscles and fibrous tissues form a ‘false joint’ meaning that actually, very little function is lost. In order to achieve this, it is vital that post-operatively, the patient undergoes fairly rigorous physiotherapy or hydrotherapy. And is encouraged to build up the strength in the muscles. The pain from the above conditions tends to come from the movement of bone on bone when the protective cartilage has been worn away; so by removing that bony connection, the pain is eliminated.
Because the function of the new hip ‘joint’ relies on soft tissue rather than bone, this operation is more successful when carried out on cats and small dogs. And is not often recommended for larger dogs, though good results can still be achieved. It also helps if the patient leads an active rather than sedentary life; as they will have more muscle mass present to stabilise the joint after surgery.
What about complications?
As with any surgery, complications can occur, but thankfully these are not common. Pain is obviously expected but can be carefully managed with various forms of pain-relief given pre-surgery, during surgery and afterwards, both in the hospital and at home. Infection is rare as the whole surgery is carried out in a surgically sterile manner but should be monitored for; with signs including redness, pain and swelling at the surgical site. Your pet will likely have external sutures that will need to be removed around 10-14 days after the procedure.
Long term, your dog may always have a slightly decreased range of motion in the treated leg. And it may even be shorter than the other one. But it’s unlikely to affect them day-to-day and they should be able to lead a relatively normal life.
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