Strange knee

[Celina1989]

My right knee is always warmer than my left knee. But especially when I rest my knee warms up even more, to over 38 C. With some walking the temperature often decreases. What can cause a knee to get more irritated in rest and improve with light activity?

If I do sports my knee will react, but mostly afterwards. My knee feels irritated all the time and is painful every day. I ice (3x a day and ice machine at night) and elevate a lot, use my brace, use supplements but nothing seems to improve. It started in January 2023 and got worse over time. I had a clean x-ray, and ultrasound (at PT). CT showed that the opposite spot of the implant, the tibia cartilage might be thinner (starting osteoarthritis?) but I don't think my symptoms would be that severe just from thinner cartilage.

I've had five surgeries in this right knee, 4 in the last 5 years due to a cartilage and bone lesion (OCD). During the last surgery I got a focal implant and after the recovery I had 4 painfree months with. Then all of a sudden at an evening I had sharp pain going upstairs. No ROM restriction, no painful flexing or extending (just a bit tight at end flexion), minimal swelling, I had a painful spot but now a small harder lump seems to be over it and I can not touch it anymore.

I did so much research, have had numerous appointments with my OS, saw a sport specialist but still unsure what is going on. If anybody can put me in the right direction it is so much appreciated!

[The_KNEEguru]

One can have a hypersensitivity to metal implants - just a thought...

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5336431/ - Metal Hypersensitivity Reactions to Orthopedic Implants

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7394811/ - Nickel allergy to orthopaedic implants: A review and case series

This can be tested with patch testing on your skin.

[The_KNEEguru]

NICE [The National Institute for Health and Care Excellence] clearly have concerns about focal implants -
https://www.nice.org.uk/guidance/ipg734 ... 6394889157 - Focal resurfacing implants to treat articular cartilage damage in the knee

[The_KNEEguru]

Here, by the way, is the link to your earlier posts - /forum/viewtopic.php?t=80191 and /forum/viewtopic.php?p=736781#p736781
So sorry that all the urls have changed since we moved to this new venue.

[Celina1989]

Thanks for your thoughts @the_KNEEguru. I've thought about metal sensitivy / allergy but I would expect that my knee would always be inflammed. It is becoming more like that (always irritated) but earlier on it only was intermittent.

I have read mostly positive news about this focal implant, especially since it is specifically made for my knee. I contacted Episurf (company behind the Episealer) and they don't recognize my complains as being implant related. I think the biggest worry is to place the focal implant with a bad indication. My knee was pretty perfect for it as my other cartilage look(ed) great.

I've now developed some harder itchy lumps on my knee. It also feels more and more tight with bending but no restriction (yet).I'm still searching for the diagnosis and got an appointment at my specialised PT tomorrow and another call with the hospital on Thursday.

[The_KNEEguru]

I'm banging on a bit here, but this is interesting - https://medbroadcast.com/condition/getc ... ensitivity - and clearly hypersensitivity to metals can be a slow process. Perhaps your family doctor could refer you to a dermatologist/rheumatologist for some tests?

[Celina1989]

I've thought about metal allergy. I've read into it before and read some experiences from other patients. It is nearly impossible to make the diagnosis without excluding everything else. I've also read that a positive test result for the skin patch test doesn't always mean that you are allergic to the implant. It is good to know that it develops very slowly, it's definetly still a differential diagnosis for me. I do notice some cognitive impairment (worsened memory) and tiredness but that might also be as a result from inactivity, stress, bad sleep, irritation/pain.

https://hipknee.aahks.org/allergic-or-s ... -to-metal/

I did some research to the few lumps on my knee and I think these are just hives. I read that hives are caused by hot / cold / large temperature differences which is very common for my knee as I am icing 3x a day and intermittent all night and in between my knee warms up to feverish temperatures. What is the normal temperature for the skin of the knee (infrared thermometer)? I think my left knee is lightly irritated as well from all compensating.

I still think it has something to do with synovitis / Hoffa's fat pad. I am thinking about Hoffa posterior fat pad impingement. May I ask you to share your thoughts on this please? It would be the only diagnosis that would explain the extreme heat.

[The_KNEEguru]

You are right that you need to keep in mind the (albeit unlikely) possibility that the hot knee is resulting from quite different pathology to the initial articular cartilage damage and subsequent implant. But according to your earlier post (/forum/viewtopic.php?t=80191) this current set of symptoms apparently came on suddenly while walking on stairs, but you had also been active with wall climbing. Is that right? You have considered something inside becoming nipped and of course there might be some aseptic loosening of the implant...

An MRI scan might be able to tease out the focus of the inflammation...

[Celina1989]

I tried to keep my post a bit shorter here. But yes I started wall climbing, with the consent of my PT and orthopedic surgeon, a few months before my symptoms started. The evening of the sharp pain I did have group PT before but I didn't have any pain during the activity. My knee never reacted to group PT (which I started after finishing regular PT) or the wall climbing other than some fatigue. My first thought was some overuse so I haven't been wall climbing since the start of the symptoms.

I had a MRI but due to the metal in my implant it had too much scattering so you couldn't see anything on the medial side. Since then I've had a clear CT scan and a clear Ultrasound (at PT). My OS can't say 100% sure that the implant hasn't slightly moved as there was no measurement done before so there is nothing to compare. But he didn't see any indication for it.

I do get sharp pain when bending around 90 degree while weight bearing and shifting to the inner side. Non-weight bearing I got full ROM although deep bending gives some tight feeling.

I've read that scar tissue issues often develop months after surgery as the scar tissue is developing to the next stage and is becoming harder. This might cause some impingement but unless it will calcify it is (nearly) impossible to see it on the CT scan. It is also an excluding everything diagnosis I believe.

[The_KNEEguru]

You seem to have covered most of the bases for now other in terms of investigation than the possible metal sensitivity. Clearly it is a big issue for you, though. I am not sure what else to suggest...

[The_KNEEguru]

I wrote to Dr Kayley Usher for her ideas and she responded -

"The increasing warmth suggests increasing levels of inflammation. This can come from a number of causes, including exercise (as you observed), but can also come from a lack of movement if there is a level of hypoxia and/or contraction and adhesion of the tissues during periods of immobility. These issues are caused by fibrosis, and it would be expected that you have some degree of fibrosis after all of your operations.

The sharp pain while walking upstairs is typical of pinching of the Hoffa's fat pad (IFP) between the bones of the joint when the joint is under load. When a leg is taking the weight to move up a stair, 7 times your body weight of stress going through it, so it's different to walking. This could well be what set off your increasing inflammation while sitting.

I suggest that you stop using that leg to move up steps, use the other leg and follow with the painful one. You'll likely need to keep doing this for a number of months. If you're lucky you have caught this in time for the swelling to subside, but if the Hoffas keeps on getting pinched it will set up a nasty feedback cycle.

If I'm correct about the cause of the increasing heat while sitting, then CPM will help to overcome this, at least while you're using it. So, I suggest that you hire a CPM and use it as often as you can, for as long as you can, in the pain-free zone. Be careful not to tear tissues, as this can be very detrimental. There are more detailed instructions on CPM use on the International Arthrofibrosis Association. "

[I do apologise that Kayley wrote this back to me two weeks ago and it slipped though my mailbox! The_KNEEguru]

[Celina1989]

Thank you very much for taking the time and effort to ask another specialist and thank you Dr Kayley Usher. There has been a positive development by quit using any ice. Apparently, my knee didn't like the icing and reacted by heating my knee up even further. Now I quit using any ice I have a "normal" knee temperature for most of the day. My knee will still get warmer after activity but "just" up to 1 degree warmer than my left knee. The downside is my knee feels weird, pressure, irritated, tingling nearly all the time. I guess I didn't really feel that anymore due to the heat overruling everything. Nights are a different story. I do miss my ice machine at night and often wake up multiple times a night with a (very) hot and painful knee. Either the pressure of the blanket or the warmth it gives is aggravating my knee pain at night. I've now borrowed a blanket lifter and it does help to sleep better. It also helps that nights are getting colder so I can just move my knee above the blanket to "cool it down".

With adjusted gait, my brace and a lot of attention I manage to limit the sharp pain to a few times a day. I really do think something gets caught inside my knee some times and IFP pinching makes sense. Sometimes, mostly after sports, I have constant pain walking upstairs. From now on I will then only go up with my left leg.

After my visit with PT in which all way good (strength, mobility, calm knee) I am now thinking more about nerve damage. It might have happened earlier than last surgery, previous RFA treatment in which the nerve is temporary disabled might have prevented pain. I had one 10 and 13 months before my pain started, and they work around 10- 14 months. I got an appointment with the same pain specialist as who gave me the RFA treatment prior to my implant surgery. It is on the 2nd of Novembre. I will ask for a injection into that nerve to temporary disable it to know if it is the cause of my pain. If it is not the nerve I am still debating if I still want a new RFA treatment as the reason the pain started in January might be that the earlier RFA worn off. I think a new RFA treatment will solve the pain but it doesn't solve the cause which could lead to (further) knee damage.

After reading all the very much appreciated advice I think it is smart to do another ultrasound in about 6 months. Even if the pain will be blocked by the RFA there might still be something going wrong in my knee, for example the pinched hoffa fat pad. It is good to keep an eye on it. I am still wondering if the inflammation caused the heat, as you would expect. Or that the heat caused the inflammation.

[Celina1989]

Last thursday I had my (pretty short) appointment with the pain specialist. The orthopedic surgeon already requested a nerve block and the pain specialist quickly agreed with it. He said that it is possible that it is saphenous nerve damage. He wants to do the treatment, either RFA or just an injection, in a sterile environment. Understablable, especially with the implant, but unfortunatly that means I need to wait another month (13th of Decembre for the appointment).

I must say that last month was better than the previous month likely to the lower temperature. I even had a few nights without waking up. I've waited so long already I can manage this month as well!

I might be totally pain free around Christmas ^^

[The_KNEEguru]

Let's hope you are turning a corner. Please keep us all informed with your progress. And let's hope the weather stays cool for you in the next few months.

[The_KNEEguru]

Also, if you have the time, perhaps you could edit your 'Signature' to list the various surgeries you have had and rough dates, so that we get an idea of how/when a nerve might have been damaged...