Howdy Doctor Fierce! A couple of times watching veterinarian shows on TV, I've seen them treat certain femur fractures or dislocations in dogs/cats by removing the femoral head to create a scar tissue joint. They never really take more than a second to explain the procedure, mostly just to say that the result is pain-free. I've always thought that scar tissue in joints is bad (in humans, anyhow), and I can't wrap my head around how a joint can still work without bone articulation. (1/2)
(2/2) Would you mind shedding light on how the bone removal procedure works? Is there an increased risk of arthritis or other complications down the line? Tax: came for the fantasy anatomy, stayed because I think your content has helped me become a better pet owner when it comes to vet visits!
This procedure has a few different names: Femoral Head Osteotomy/Ostectomy (FHO) or Femoral Head and Neck Excision (FHNE) being the most common.
It’s a salvage procedure performed to alleviate pain. It’s commonly performed where the femoral head is broken, malformed or otherwised damaged. Fractures are common in cats and small dogs, but necrosis of the femoral head or severe hip dysplasia are other common reasons. A total hip replacement have have been an option in some cases, but is about three times more expensive.
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Basically the hip is a ball and socket joint. With this procedure we remove the ball from the socket. This will create a false or floating joint, but because there are no fracture fragments to rub against each other, and no friction on the articular surface of the joint, the animal has less pain. All the muscle attachments are kept in place and it’s those muscles which are important in movement.
There will be some boney changes over time, but no arthritic pain because there’s no joint any more. One leg may be a little longer than the other, but dogs and cats typically walk with a slight bend in their knee anyway so they cope well with this procedure.
This works well with smaller, lighter animals with good muscle tone. Larger, obese or already weakened animals don’t do as well.
Briefly, the surgery involves a small incision over the hip joint. Sometimes the femoral head is already fractures, so it’s simply matter or removing the unconnected ‘ball’ of the joint and smoothing out the edges left behind. Sometimes you have to cut the femoral neck first, and then retrieve the ‘ball’ and smooth your edges.
Some animals live with a slight persistent limp because one leg is a different length, but generally they cope quite well.