FAI Hip Impingement (Femoro-acetabular Impingement)

FAI Hip Impingement Awareness facts - It is estimated that approximately 15% of the young, adult population have hip impingement, so who do you know that might have it?
Hip impingement causes painful labral tears within the hip socket.
Hip FAI symptoms are misleading to the average medical professional, as FAI hip impingement pain frequently presents as low back pain and interesting only 10% of back pain is ever clinically diagnosed and cured... Which begs the question what percentage is actually caused by hip FAI or hip impingement, as its otherwise known.
The more active you are, the more likely you are to trigger hip impingement symptoms, so busy mums and gym bunnies beware... but at least you're in good company as many premiere league football players have also suffered FAI hip pain.
Hip impingement is diagnosed through x-ray and labral tears are diagnosed through MRI arthograms - but both need to be read by hip consultants specifically trained in FAI hip impingement.
There are 60,000 hip replacements every year in the UK and it now appears that FAI hip impingement, over the years, could be the leading cause of hip osteoarthritis. A silent epidemic.
Hip arthroscopy can reduce the hip impingement and reattach the torn labrum to the hip socket. This surgery can eliminate the pain and disability caused by FAI hip impingement and divert the need for hip replacement in later life.

Also please feel welcome to join in our help and advice forum for support. We have 3 advising FAI expert hip surgeons, 3 PT/physios and a sports medicine doctor as well as the largest international FAI hip impingement forum on the net:

Saturday, 17 April 2010

Answers from FAI expert

 I have pretty much copied in my latest correspondence between my Surgeon and myself, via his secretary..
I can't say I am too clear about where I am at, other than I'll probably be having another MRI soon.

Hi Louisa,

I have had a response to your questions from surgeon, as follows:

Q: What dose of anaesthetic and steroid was given and was this a “stronger” dose? - The two injections in the past have not affected the pain experienced when she sits down and this one did. Why? Also, why did the pain she gets when she sits down never go away after her hip arthroscopy?
A: 2ml Depo-medrol 80mg and 8ml of Marcaine. I wouldn’t call that a strong dose but a normal dose for a hip injection. I am not sure if Louisa is referring to the two previous hip injections that she has had in the past or to the hamstring injections. If she is referring to the hamstring injections then I would conclude that the hamstrings are not causing the problem. If I knew exactly why the original pain had never completely disappeared I would be able to treat it, but unfortunately her response is not a typical response that is seen in the majority of the hip arthroscopy patients with this type of pathology and therefore more difficult to pin down.

Q: Louisa’s range of motion is quite good. Would this be expected if she has developed scar tissue?

A: The number of patients that I have treated so far with adhesions post hip arthroscopy is very small. But in the group with this problem I didn’t feel that a reduction in ROM was the problem. Because we are talking about 1-2% of the hip arthroscopies as a group it is too small to see patterns and be able to identify possible causes for residual problems.

Q: The effect of the recent injection lasted no more than 4 hours. You said it would possibly last for 5-6 hours. Is this because Louisa’s pain is now so chronic and nothing will have a longer-lasting effect?
A: Each patient’s reaction to an anesthetic is individual. If I specify 5-6 hours then this means that this can be expected in the majority of patients, but it can last a shorter or longer amount of time as well and we have no way of knowing this with each patient. Chronic pain is unfortunately much more difficult to resolve because the permanent stimulus to the nerve roots telling the brain that there is pain might still continue even though the original problem has been solved.

Q: Louisa said that the injection took away the pain she feels when she sits down and was replaced by a sensation of deep-seated “itching” within her hip. Does this tell you anything?

A: It tells me that there could be an intra-articular cause which is at least partially responsible for her pain.

Q: Do you feel that Louisa has some residual impingement, or has she likely developed scar tissue?

A: That I can’t answer at this moment. As I discussed with her, if we felt that the injection gave her a positive response (i.e. blocked the pain), which I think she has had, at least partially, it would probably be a good idea to re-scan her hip.

I would say that the diary of symptoms over the past week is what could be expected from the effect of the local anesthetic firstly, and then subsequently, when the steroid kicks in, her symptoms start to improve again.

Q: Louisa has noticed that her gluteus on the right side seems to increase and decrease in size and she is able to induce “impingement” symptoms in the right hip herself in some positions. Can you explain this?

A: What Louisa is able to induce is pain, but there is no evidence at present that this is “impingement” and this should not automatically be assumed.

Q: Louisa seems quite convinced that there is some residual impingement remaining. Is this a possibility?

A: We have discussed in clinic how I treat a pincer abnormality and I have confirmed that she doesn’t have a coxa profunda, which is the more global-type of over-coverage.
I assessed the zone where Louisa had a wave sign and then decompressed the acetabulum in the area of unstable cartilage followed by a labral repair. Assessment of the impingement is done dynamically during the operation.

Can there still be residual impingement? - nothing is impossible; however her outcome scores and assessment do show that she is deviating from the pattern that the standard group of patients with this type of pathology follow (call it disproportionate symptoms) and we therefore have to start to look realistically at would could be achieved with further surgery if permanent stimulus to the nerve roots continues.


I hope the above information is of some help. If you are amenable to a re-scan I can ask the MRI department to arrange an appointment with you. I know you said that you were not keen on another arthrogram, but your surgeon would not consider a second arthroscopy without a scan, as the results of the scan will be important in deciding further appropriate treatment options if something does show up. I understand it is difficult and frustrating for you not to have a definitive answer, but I think he has been as informative as he can at this stage. If you have a think about things over the weekend and let us know if you would like an MRI scan arranging.


  1. Hey Louisa, at least he got back to you, its a good start, though not the clearest of answers. MRA would give you answers on any joint pathology (labrum, scar tissue etc) and you would be able to see any residual impingement as well. Plus if you are not happy at that point with the prof's views, you could the take the images to see villars or another surgeon for a second opinion.

    How is your pain at the moment? Hope everything is well on track for the house move.
    Sam xx

  2. Hi Sam,
    Yes my thinking exactly, even if I end up back at Schilders, Trouble is all these appointments are pricey.. I have Bupa, but for incare, day case and post surgery, so doesn't really cover extra appointments and moving will have us short of cash, everything tied up.
    Pains weird. I have new catching as of last month, in the groin and whilst prior to surgery I had clicking there, I didn't have catching like this, not all the time.. makes me think scar tissue.
    Yesterday I managed to take my little boy to the movies, something that required diazapam to stop spasms prior to surgery.. and I was fine,then had to sit waiting at the docs for half an hr (only to be told I have shingles! I think its not, I think its a small patch of chicken pox as its not painful and never had c pox!)
    And after all that sitting I was surprisingly fine, surgery? steroid? fate? But today a very diff story muscle spasms galore! WWWWHHHHHYYYYY????
    Anyway I'm at risk of moaning on, how are you feeling, you sound to be going thru the mill, still somewhat??

  3. Hmmm, maybe you have torn labrum with the cathcing sensation, I know people say that that's what it feels like. Sounds like the pain is very unpredicable, which is highly irritating i'm sure. At least you were able to have fun with your son without in hideous pain. I suspect the steroid has kicked in fully and is giving you relief from the sitting pain, so it does sound jointy related.

    Surely you can have the MRA on the NHS, although you may have a wait a while longer, the prof can refer you normally to save you paying. And perhaps he can give you results by phone or email to save actually paying to go see him?

    I'm doing ok thanks, my wound popped open last night about 1cm, and has been draining clear but blood stained fluid since. I rang the duchy who said to see out of hours GP. I spoke to a GP (embarrassingly one I was a medical student for back in november) who has given me antibiotics and some steri strips to close it, but didn't actually look at it... so keeping fingers crossed I don't get an infection and it stops oozing soon! I don't do things by half do I?? bloody hips.

    Sam xx

  4. Good job you're a doc! I thought I'd got over my blood phobia until frid when my one yr old cut her head open on a door stop.. I held it together till my hubby got home then wanted to puke and passed out! What a wuss, there was me thinking I can get my head around all this medical stuff, maybe I should have a career change! Err no!
    Bupa cover the tests, but actually I'm too busy for at least the next month.. gotta keep hip stable this wk as hubby goes to Hong Kong on work Thurs and I have the 2 children, my mum helps but its not the same, then a week before we move, then the move, then 2 weeks of house jobs, plus an ad I have to film in about 3 weeks, so I can't for about 5 wks... and a naive bit of me hopes that's all I need to improve enough to be better, after 9 months I think that's called denial!

    Do you know if I have an MRA now will it wash out the steroid or is that just in my system now?

    ps Glad you made it back to work, you deserve an award!

  5. Great answers Louisa, stink that nothing is definitive though eh. The MRA may be the way to go so that nothing is missed. What about a CT scan to assess the joint in 3D? Lots of radiation, I know, but it is the ONLY thing that diagnosed me with CAM impingement which I noticed hasn't been mentioned with you?
    Valium is your friend when you have scan nerves ;-)

  6. Thanks Jess, yes I've been after a scan for some time to asses extent of retroversion, but I'm told its not necessary esp as retroversion is mild, though I struggle to marry that with the statement my pincer's in the worst 5% he's seen - unless I'm missing a step, which is VERY possible! I must remember to ask that!!
    But yes I think it was 'goodnight nobody' who finally had a CT scan diagnose her failed 2 arthroscopies with a fragment of osefied?? scar tissue caught in the socket, so I'd say valuable on that level if nothing else.
    Myself and valium have become quite well acquainted thru our mutual MRI friend! Hehe.. makes the day of MRI way more pleasant, for a start I stop been like a snappy jack russel with a sore paw!

  7. I wouldn't have thought the contrast from MRA would effect the steroid much because it will have dampened down the inflammation by now and I'm not sure if it hangs around or is absorbed and just has a lasting effect... will see if I can find out.

    Yeah, unless something magic happens in the next 5 weeks, it doesn't sound like you will just wake up pain free. There is obviously something still going on in there, its just pinning it down. I would get the MRA asap, as at least then you know what you are facing.

    Perhaps its worth asking the prof more about the retroversion and your angles. Even explaining you know of a hip chick who needed a PAO because she had severe retroversion (though I have only found 1 other weirdo like me and he is in the US, so its really not very common, but open debridement for pincer and cam is much more common).

    Jess's suggestion of a CT is good too, but the radiation is pretty high. Though, I had a second CT 12 months after my PAO (but before my open debridement) to assess if I still had residual impingement causing groin pain - and I did and interestingly, it was based on this that he did the open, not on the fact my first and only MRA showed significant labral damage and rugby ball shaped femoral head... so perhaps its worth pursuing?

  8. My consultant acknowledges that i have retroversion, but that its mild.. but then my pincer is supposed to be in the worst 5%, have I missed something, isn't that a contradiction? ..I wish I could remember to ask all the right Q's, is its not as if he doesn't allow the time in appointments!

    I'm after a CT but he says he finds them of no real use, he also says that my retro is ok/mild and he took a peak at the back of the socket for labral damage in op and all was ok, though I'm not sure if it would be otherwise. I think I may as well push for all the tests, if I don't improve (still in denial!) as I need to do something to make things clear.
    CTs are 3d right?
    I don't know how you can deal with so much surgery, your inner strength is amazing - I just want to raise my children without all this, but hey who gets just what they want??! :)

  9. Would BUPA cover you to see another surgeon, pref one who does all the diff surgeries? Perhaps its time to at least get a second opinion, just to see if they agree. Do you have your own copies of the scans/xrays to take with you? If the prof only does scopes, you have to worry that he only sees the problems he can fix with that technique. it does seem a bit odd that he says your in the worst 5%, but then its only mild - and what is "mild" in terms of numbers.

    The CT scan itself is 2d, but all the orthopods ahve some funky computer thing that makes it a 3d image, they can spin and play with to look at the whole joint - its pretty cool.

    Not sure quite how I have done it, 10 surgeries now (well 9 anaesthetics), just desperate to be at the end of it all. Right hip still not completely right, but decided that perhaps this is it for me, as good as it gets and I can live with it - though I am still on painkillers regularly so we shall see if it gets worse when I am off everything, then I might have to see about further MRA, poss scope. I think as long as when I start work properly in august as a doctor, if I can't function and it affects work, then something will have to be done. fingers crossed its fine. Have noticed it pops audibly everytime I go from sitting to standing for last month or so.. getting more frequent... who knows?!

  10. Hey Louisa:

    I had the hip arthroscopy surgery in March for labral tear and hip impingement (both cam and pincer).

    I want to thank you for doing this blog. It really helped me to read about your experience with the surgery and the recovery.

    I am four weeks post-op and am weaning off the crutches, which is making my hip sorer than it has been the past two weeks or so. I am also on an anti-inflammatory until end of April.

    I am very afraid of getting off crutches and the meds, while my physical therapist continues to ramp up my exercises!

  11. Thank you and don't be afraid, just do it at a pace that you're comfortable with.. if you feel your physio pushes you too hard either ask them to slow it down or find one with a gentler approach (that's what I did in the end) and make sure they're familiar with your proceedure and have treated patients like you before too.
    There are no hard and fasts with this surgery as its new and each consultant has their own way. So if it feels to soon to come off crutches, really don't.. I was told sic weeks and I struggled till I think 8 wks. SO if it feels wrong it probably is wrong for you.
    If it flares take whatever you're doing down a peg and feel free to ask for help..
    I have only just discovered the faceback FAI page, if you don't know it, have a look its a great source of fellow patient info.
    Take it easy X