What does it mean that I have 2 branches involved?Posted by SKULL on 11/06/04 at 21:38 (163123)
My neurologist said it was very intresting that I had 2 branches of my tibial nerve involved. My dx is osteochondral defect. I have a cyst but the cartildge seems to be intact. (the MRI said it was hard to visualize.)
When I had a tinel's test the other day with my foot dependant I felt it spread down to my arch to my big toe and 2 little toes, then it went to the other side of my foot and my little toe.
My podiatrist said I had referred pain.
I am not sure what the 2 branches mean and what referred pain is. (I just know it hurts.) Where does the tibial nerve branch?
ALso, I've heard the term high tarsal tunnel. I am an RN, but I can't find a decent illustration to really explain the nerve path to me other than it goes through the tarsal tunnel. Can you help explain that?
Re: What does it mean that I have 2 branches involved?Dr. David S. Wander on 11/07/04 at 15:20 (163167)
The tibial nerve branches at the bottom of the foot and two of these branches are the medial and lateral plantar nerves. These are normally occuring branches and there can be an entrapment of the nerves at different levels. This would explain the results of the Tinel's sign/test. The tibial nerve also sends branches higher up and these branches can vary in location and number. There is an amazing foot/ankle anatomy book written by Saraffian that describes dozens of variances in the anatomy. An osteochondral defect in the foot usually involves the top surface of the talus. Therefore, it depends on where your sypmptoms are, and then it must be determined which level of the nerve is causing the pain. If the nerve is blocked with local anesthesia distally (where it branches into the bottom of the foot) and the pain disappears, it would indicate a more distal level of entrapment. If there is still pain following the distal injection, it would indicate that if it is a nerve problem, the problem is occurring at a higher level. This sounds a little confusing, but I hope it helps.
Re: Dr. WanderDarlene on 11/07/04 at 16:00 (163169)
If the posterior tibial nerve is numbed would that eliminate all pain in the bottom of the foot? I have pain in the tarsal tunnel area, heel, arch and bottom of the great toe. Some doctors just release at the tarsal tunnel. Some follow the nerve surgically to the calcaneal nerve and I think the medial and lateral nerves. So my questions is how would you know before going in where the release(s) should be?
Thank you for your thoughts.
Re: tarsal tunnel painDr. David S. Wander on 11/09/04 at 07:40 (163313)
This is an excellent question. In my original response to 'SKULL', I was addressing his issue of pain that the doctors thought may be referred pain. He gave a diagnosis of an osteochondral defect, which is in the ankle. In that case, if the nerve was blocked distally where it divides in the foot and the pain persists, it would indicate a higher level of nerve entrapment/pathology. In your case it is very difficult to determine where the problem exists. If the very distal aspect of the nerve is blocked and the pain resolves it may indicate that the entrapment is lower and not at the level of the ankle. When I perform tarsal tunnel surgery I inspect the area and release the 'envelope' containing the nerve at the level of the ankle and I do believe in also releasing the more distal aspect of the nerve as it divides. At the distal aspect of the nerve where it branches it travels through a fibrous ring of tissue (porta pedis) and this is often where the problem exists. I hope this helps.
Re: Dr. WanderDarlene on 11/09/04 at 09:00 (163324)
Thank you for your very educational response.
So, ankle pain per se doesn't mean that the nerve is entrapped in the tarsal tunnel? It could be trapped in the porta pedis area and still send pain and tenderness back to the tarsal tunnel area?
Is there any diagnostic tool out there that would tell me exactly where the problem is? MRI? Neurography?
I prefer the least amount of cutting as possible.
It's interesting and unfortunate that more advances have not been made in research in this area.
Re: Dr. WanderDr. David S. Wander on 11/10/04 at 18:19 (163485)
I think you may have misunderstood my answer. I stated that if the nerve is blocked distally and the pain disappears, it would indicate that the problem is distal. It would be very unusual for a distal nerve block to eliminate pain at a higher level (ankle). However, blocking the nerve at a higher level will 'knock out' the nerve distally and it will be difficult to assess where the entrapment or problem exists. A doctor can start distally and keep blocking higher up to see when the symptoms disappear. If you start at the top, you'll be blocking the nerve from that point forward and the problem can exist anywhere in between. I hope that clears it up a little for you.