Brief Answer:
Radiating pain can be from a variety of causes

Detailed Answer:
Good evening. My name is Dr. Saghafi and I am a neurologist from XXXXXXX Ohio, USA. Thank you for your question. Although you are correct in stating that a radiating pain traveling down the buttock to the knee could be similar to sciatica but in reality pains that terminate at the knee are usually NOT sciatica and termed LUMBAGO. Having said that, it is absolutely NOT NECESSARY for a pain radiating down the buttock to go into the foot for it to be actually sciatica.

In sciatica it is typical for there to be weakness in the foot along with numbness and tingling along the way as well.

Other possibility given the fact you are referring pain into the groin would also to be that of an arthritic right hip which could easily give you exactly the symptoms you have without the sensory or motor changes typically seen with sciatica.

I believe the most likely cause of your buttock to knee pain would be found in the hip and is not an entrapped spinal nerve or nerve root. Definitive diagnosis, however, can only be made by doing a careful neurological evaluation of your areas of pain followed by necessary tests or diagnostic studies.

Nerves that supply the colon or rectum cannot become entrapped and cause the symptoms you have since there's no relationship to any trajectory of pain radiation that would initiate in the buttock and terminate in the knee.

The query has required a total of 12 minutes of physician specific time to read, research, and compile a return envoy to the patient.

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Brief Answer:
Rethinking the question

Detailed Answer:
Good afternoon dear lady from across the Pond......the very LARGE Pond.....

So upon further reflection and study of your symptoms I must admit I did not take into very much consideration what turns out to be a rather important piece of information which you provided but which I failed to give its due until you mentioned it again....and that is the fact, that pain is relieved upon moving your bowel.

Therefore, when looking again at the nerve supply of the rectum and colon....it actually does make some sense that pains that you're describing relieve upon moving the bowel which would take pressure off of the hypogastric plexus nerves. This conglomerate of nerves processes from the sympathetic and parasympathetic chains of nerves which form a superior and inferior set of nerves. Now, we're talking about nerves that supply not only the rectum but also the bladder, and uterus.

Do any of your pains alleviate when you relieve your bladder without emptying the rectal vault? Do these pains reproduce while having sexual relations? Are there are any other situations under which you can bring on or reproduce these pains.

Explaining why your pain is, however, in your buttock and radiates to the knee is slightly more difficult to explain UNLESS there is some type of pressure from between the rectal vault region and the muscles through which the sciatic nerve may travel. In other words, if there was enough distention of the rectum with fecal material that it were to cause a displacement against muscles and tissues that carried elements of the sciatic nerve then, I could envision the pains you're talking about otherwise, those pains are difficult to ascribe to the hypogastric plexus which feeds the rectum and other pelvic organs.

And so in putting this together, and in order to avoid missing anything that could be going on, and also for the fact, that this pain is of recent onset I would ask that an MRI with and without gadolinium contrast be obtained of the lower back and of the colorectal region to rule out the possibility of some type of entity that could be space occupying between the rectum and the piriformis muscles and/or paraspinal muscles in the lower lumbar/sacral regions.

I know that in England you are somewhat at the mercy of someone to write orders for these types of tests and perhaps this seems a bit high flying but based upon your history of precise and localized pain which is radiating and persistent until you have a bowel movement I believe this imaging study is well worth the trouble to get. If it comes out clean then, so be it.

I do believe this to be a more spot on answer given your symptoms and hope you follow my suggestion through of the imaging study. If you agree that this is a much improved effort over last evening then, may I ask your favor of a HIGH STAR RATING with some written feedback?

Also, if there are no other questions or comments, I'd appreciate it greatly if you would CLOSE THE QUERY on your end so this question can be transacted and archived for further reference by colleagues as necessary.

But please keep me informed as to any developments in your condition. I'm interested in staying in contact with you. Please direct more comments and questions to me in the future at:

bit.ly/drdariushsaghafi and I would be honored to answer you and continue this discussion.

All the best.


The query has required a total of 48 minutes of physician specific time to read, research, and compile a return envoy to the patient.

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