Avascular Necrosis
 

My son (now 11yo) and I were banged-up in a motorcycle accident in 1/09. The proximal neck of his femur was broken, and a recent visit with his ortho (ChOA) indicated signs that the ball of his femur is beginning to break down (avascular necrosis). The discrepency in his leg length is 1.5 inches now, and the Dr. is beginning to mention a few procedures as time moves on.

First... perhaps sooner than later, they would like to "turn-off" the growth plate in his good leg to allow the injured one to "catch up." Can any of you expound on this? I don't know the questions to ask really.

He's also going to explore a procedure that involves moving a graft of fibula to the neck of his femur to control the AVN. Any thoughts on this? Success rates, etc?

Please him in your prayers, and say one for me as I try to find some peace in all of this. :(

I'm sorry to hear about your son's AVN. We see a lot of AVN in our leukemia patients due to the chronic use of steroids - some of our patients end up needing surgical procedures due to its severity. AVN of the femoral neck/head is not that uncommon in pediatrics, but is typically seen in obese children in this age group (called Legg-Calve-Perthes disease) - trauma-induced AVN is less commonly seen.

I'm glad yopu are at CHoA. Make sure he is seeing pediatric-trained orthopedic surgeon who sees a fair number of growing boys with this condition. It will be important for the radiologist and surgeon to see how things have progressed over time to help with the treatment plan. If he is having progressive collapse of the femoral head there is more reason for concern than if it has been unchanged since the motorcycle accident. As outcomes tend to be different from hospital to hospital you will want to ask the surgeon his experience with the proposed procedures and what kind of long-term outcomes he sees. Then ask him how this compares with the national average and if he would recommend another surgeon if he seems less than experienced. If someone gets offended by this question it's their problem - not yours.

The growth and leg-length discrpancy is a big concern - there are several ways that this can be dealt with depending on your son's growth plate status which range from shutting down growth on the longer leg to exploring leg-lengthening surgeries on the shorter. This will need to be discussed with the surgeon.

As far as the fibula graft - typically this is done in tandem with taking out cores of the necrotic bone (dead bone out, healthy fibula in). The thought is that health bone with good blood supply can help promote growth and healing in the necrotic area.

Is your son having any limited range of motion, pain or other problems in the affected hip?

You will want to discuss the use of anti-inflammatory medications and other pain meds if he is hacving discomfort and discuss physical activity limitations (low-impact such as swimming and biking tend to be preferred).

All of these recommendations are generalizations without knowing or seeing your son's specifics - and I am NOT a pediatric orthopedic surgeon.

Feel free to PM with any further details or questions. I had fairly significant AVN myself - 80% necrosis of the femoral condyles (the knobs of the thigh- bone that are behind the kneecap).

HTH

Chris,
He is in our thoughts and prayers,
Take Care
AO

Thanks!
 

And thanks Arnold. I've had a lot of time to reflect over the past year and half. That boy means everything in the world to me.

FWIW, I'm thinkin about heading up that way before summer's out. I'll shoot you a message when.

AVN
 

I thought you were out of the woods on this one. Sorry to hear about your son. I deal mostly with adult reconstructive surgery, hips and knees but we do see a lot of AVN in that realm. For the skeletally mature there are a few options, core decompression, free fibular grafting where they take a piece of bone from the fibula and graft it into the hip. The idea is to structually support the head and get blood flow into the area with the attached vascular bundle. If you're goning to have that done, Duke is the place to go. I'm not sure if they are doing it in kids. Another option is the tantelum rod , made by Zimmer goes by the trade name "Hedrocel". The idea here is to provide a strut similar to the fibula but using tantelum which has a similar matrix as bone. There is no active blood flow enhancement with this rod. It is the least invasive of the above options. Then there is hip replacement which should not be considered at his very young age. I would hope the lesion is small and does not involve much of the articular (weaght bearing) portion of the head. The good news is that kids his age have highly vascular bones and heal well. I will pm you with the name of a really good ortho man in your area if ever you need a 2nd opinion. I hope all goes well for him, you guys have been through it.
Boomer

Let me know!

Thanks Boomer. Duke *is* where they propose sending him for the free fibular graft. His ortho is preparing a packet to send to them for consideration. Evidently the candidate has to be ideal in order to proceed. In the mean time, there is a medicine that I can't recall the name of that they would like to put him on. Evidently it's similiar to what is prescribed to patients with osteoporosis. It has shown some promise in the area of controlling the breakdown.

Thanks for everyone's thoughts and prayers.

Best of luck on the surgical assessment at Duke - they do a lot of good/novel things there.

I believe medication they are recommending is a bisphosphonate - these medications were designed to combat osteoporosis but have been found to have benefit for patients with decreased bone mineral density - we tend to use these medications in some of the children we treat who are expected to have long-term steroid medication use.

There are several different medications in this class on the market, all have a drug name ending in "dronate" or "dronic acid". You may have seen advertisements for Boniva, Zometa, Fosamax or Aredia - all members of this class of drugs - on television.

There are a few studies that discuss bisphosphonate treatment for AVN in pediatrics that I could find while reveiwing the scientific/medical lioterature. There are a few out of the UK and Australia that I focused on. It looks like there is less progression of femoral head collapse (breadkdown of the ball of the thigh bone), improvement of pain and function for most patients (up to 77%). There have not been any large-scale randomized controlled trials (considered the best way of evaluating the efficacy of a treatment when compared to current standard of care) that I could find, but the few studies reported are definitely promising.

HTH.

That's it!, and appreciate the PM followup on the potential side effects. I'll have to discuss them thoroughly, because he *will* need braces, and probably some tooth extractions.

Keep the prayers coming.

Quick update...
 

Word came back from Duke that my son is not a candidate for the free fibular graft. Apparently his necrosis "is not bad enough." Whatever that means. (that's what the ex said the Dr. told her). Anyhow his next visit is to get a second opinion with a top guy in the field of pediatric orthopedics at Emory. Then the bisphosphonate treatments commence in July, with a follow-on surgery to slow the growth plate in his good leg in order for the injured one to "catch up," as he grows.

I know it can be frustrating to hear that your child is not a candidate for a procedure/treatment for which you had high hopes -we have to have that discussion all too often in my specialty and we don't like to give that news from our end, either, especially if we feel a child would benefit but does not meet hard and fast research criteria. The fact that the docs do not feel his AVN is "bad enough" to warrant a relatively new (read:experimental) procedure is somewhat encouraging. I hope you get the information you need at your trip to Emory. Keep strong and optimistic!

The Hospital for Special Surgery in NYC is arguably the best in the world. This link is for their orthopedic dept; it may be worth your time to contact them.
http://www.hss.edu

Since you posted that braces will be required in the future....
 

KPOW-
Depending on which bisphosphonate meds he will be taking, you might want to go ahead and get an orthodontic consult now. IV bisphosphonates are considerably more potent concerning the long term side effects that I have seen and manage in dental extraction healing, etc. I would discuss whether there is a need for future extractions due to ortho related spacing issues. If there is a need, then get the orthodontist's opinion on performing the necessary orthodontic extractions before one of the stronger bisphosphonate meds is to be administered.