Canine Femoral Head Osteotomy: Great (Or Not So Great) Expectations with (FHO)

Femoral head osteotomy (FHO) is the surgical removal of the ball and neck of the femur, in the hip joint.

It is used in cases of

  • advanced hip dysplasia where the hip joint has also become arthritic
  • in complex fractures
  • cases of avascular necrosis (lack of blood supply to the bone–a genetic condition called Legg Calve-Perthes, seen mostly in toy breeds is an example of avascular necrosis)
Canine Femoral Head Osteotomy: Great (Or Not So Great) Expectations with (FHO)

Physical therapy post-FHO

When I get a new referral to see a canine patient post-FHO, two immediate questions come to mind: 

  1. How long ago was the surgery and
  2. Are the dog parents realistic in their expectations of the outcome?

From experience, I know that if the parents have waited a month or 2 (or longer) after the procedure to call me and/or are expecting their dog to walk as well or better than before the surgery, I am about to face some heat!

FHO is not the only option for these conditions, but it is probably the most commonly chosen.

Is FHO a good option?

If you think I don’t sound like a fan of the FHO, you are right. Nobody, even the surgeon, is a fan of FHO. 

This is because it is a non-reversible “salvage” procedure and not a truly corrective one. Given the other options available, however, it is usually a very practical choice!

Alternative options to FHO

Triple pelvic osteotomy (TPO)

TPO is available for young dogs up to 1 year of age. It nvolves cutting and re-positioning the bone and re- angulation of the joint

Total hip replacement (THR)

Total hip replacement (THR) inserts an artificial hip (endoprosthesis), and is used in dogs over 1 year of age.

Both options have a high success rate, but involve longer recovery and are much higher in terms of cost.

Indications for FHO

The FHO becomes, if not the optimal treatment of choice, an economical solution with a shorter recovery period.  

It is performed more on smaller dogs, less than 40 pounds. It is not highly recommended for large dogs.

Managing expectations

The key is to understand why it is being done and what to expect afterward. 

When the hip joint is damaged by one of the conditions described above and conservative measures have not been effective, the hip will continue to worsen without surgery.  By “worsen”, I refer to:

  • degenerative changes as arthritis
  • fragmentations and bone spurs which will become painful and debilitating for your dog

What does FHO accomplish

When the FHO is performed, it allows a false joint to form in place of the normal ball and socket. 

From that point on the “hip” is biomechanically altered and the leg becomes shortened. Even with physical therapy and rehab, there can be some recurring deviations and lameness in gait with less weight borne on the leg than before the surgery.

What will FHO do for your dog?

Many times I have heard a dog owner state “My dog seemed to walk just like this or better before. Why did I have this done? My response is “Your dog is now free from pain and secured from future crippling” arthritis and degeneration”.  

Though with FHO, the return to full function is guarded, the quality of life is enhanced. And the owner still has his/her retirement savings intact.

You may be wondering how the dog can sit or walk after their femoral head osteotomy (FHO) without the firm contact of the femoral head in the socket. 

Photo OrthoVet Super Site
Image: enpevet Ltd

Facilitating the process with physical therapy

Initially, they will redistribute their position to bear weight more on the front limbs and other hind limbs.

This can lead to overcompensation. Therefore it is essential that physical therapy is started very soon after surgery to help the formation of a “false” fibrous joint. This is facilitated through an early range of motion and weight-bearing exercises.

The “empty” space fills in with soft connective scar tissue to form a new “pseudo” joint. The pseudo joint forms according to stimulation and stresses put onto it (Wolf’s Law). Range of motion and weight-shifting activities provide the needed stimulation.

The veterinarian and physical therapist can show the dog owner how to do some home exercises, along with scheduled rehab sessions.  

When to start physical therapy?

This can start immediately after surgery or 10-14 days after surgery when the sutures are removed, depending upon the surgeon’s protocol.

If you choose to wait 2-3 months after surgery to “see how it goes” before deciding whether to try PT, it will be too late to maximize the formation of the fibrous tissue.

Other ways to help your dog’s recovery

Along with early physical therapy exercises, you can apply moist warm heat packs to the hip to help bring blood flow into the region. 

Be sure to place a thin towel over the shaved area first, then the heat pack on top, to avoid burns. The temperature should be warm, not hot.

Plan for a quiet homecoming after surgery, especially if there are other pets in the house.  

Place carpets or non-skid runners over tile or wood floors to avoid your dog slipping.

Pillows can be placed in several locations on the floor where your dog normally likes to sit, to help them ease to and from the sitting position.

Avoid the use of stairs initially and use a leash with a collar or harness for the stairs when the vet tells you to resume.  

Contact your vet for adequate medication for pain and inflammation, to allow your dog to handle the early exercises needed to maximize the formation of the “false” joint.

The outcome

This new “pseudo” joint will not have the stability of a normal hip and running, jumping and hard playing may become somewhat limited. 

But you can expect your dog to resume walking with near-to full weight borne on the limb, for fair to good distances, and to enjoy a comfortable high quality of life.

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