Laurie's Blogs.


Dec 2012

The FHO - The Good, the Bad, & the Ugly

I may have mentioned this before, but I believe that the universe sends you series ‘messages’ that are intended to help with your learning.  In clinical practice, I find that we will be referred a number of similar cases, that in the end, help me to identify a commonality / common thread for that particular type of case.

So recently, my clinic has had a run on femoral head ostectomies (FHO)… that were all not progressing.  So, that’s what I want to talk about today.

A dog with an FHO surgery should be walking on that leg (or at least using it for balance) by 2-weeks following surgery.  When they aren’t I tend to think that something is wrong.  And what can go wrong?

1)   Not enough of the femoral neck is removed.  This is the most likely cause of a post-op non-use FHO.  The only remedy is to go back in surgically to remove the ‘spur’.

2)   In a young, growing dog, the femoral neck might actually ‘grow back’ – creating a bone spur or a profuse amount of boney exostosis.   This doesn’t tend to end well.  When the veterinarian goes back in to smooth things out, the bone spurs may just comes back again in time.

3)   The lesser trochanter may have been inadvertently removed.  In this scenario, iliopsoas no longer has an attachment.  Thus the only thing enabling flexion of the hip, is the Sartorius, and to a less extent the Rectus Femoris.  These dogs can function, but they are never as good as they could be – and these muscles become very tight and contracted.

4)   The iliopsoas could have been ‘nicked’ during surgery.  I have only heard of this from one surgeon who reported, “It didn’t turn out well.”

5)   The animal had significant pain (and atrophy) prior to the surgery, that you are also dealing with pain management and ‘psychological’ factors to get the animal to ‘buy in to’ using the leg.

How do you assess for ‘things gone wrong’?

Firstly, I do ROM (flexion, extension, and often both rotations, plus abduction), and I am looking for either crepitus or an empty endfeel (this is when the examiner stops the test because the patient is expressing pain, but there is not an appreciable tissue resistance in the examiners hands).  The degree of pain is also something to take note of… in a normal post-operative recovery; the animal may experience soft tissue tension with the different ranges of motion, however extreme pain is not typical.

Secondly, I perform joint glides.  Moving the femur dorsal & ventral, cranial & caudal, feel for an obvious clunk or again, and empty endfeel.

As for soft tissue problems, specifically palpate sartorius, rectus femoris, and iliopsoas.  Feel for any abnormalities or changes in muscle tone, that are substantially painful on palpation. 

The last category (extreme deconditioning) is deduced simply by a compilation of assessment findings.

But what do you do?  Firstly, if there is pain, crepitus, or an empty endfeel and the dog is not using its leg at the 1-month post-op stage, then refer it back for a radiograph.  I tell the owner that ‘sometimes a bone spur can grow back and that I’d feel more comfortable checking on that before pushing the dog to use the leg’.   This way the owner does not go back to the veterinarian mad.

Now… what to do with the FHO is another blog or video… but the point I wanted to make was that as the rehab therapist, it is up to you to advocate for the dog, and to be aware that bone spurs left behind can be a real problem in these not progressing FHO cases. 

Until next time…