Does anyone know of treatment/s for sciatic pain/cramp caused by bowel problems (NOT related to the spine?

Severe immobilising cramp and numbness in left leg (from hip to ankle) always associated with constipation and/or trapped gas. GP's response is that the only known cause must be related to spinal /back problems - but online research suggests that infection of muscles surrounding the sciatic nerve can cause sciatic pain.

I'm slightly confused by your question. You say you're sciatic pain is from an infection, yet you link the pain to constipation. I'm going to answer this question from the standpoint of constipation. Start taking Metamucil powder, 1tsp. first thing in the morning with a large glass of water And last thing at night. Acidophilis capsules should be taken twice daily with the Metamucil. This is going to start relieving the constipation and the trapped gas.

If you really want a deep cleaning of your intestinal system, have a colonic done by a professional. This will really get trapped waste out of the intestinal system and help it start functioning better.

Due to malfunctioing of sciatic nerve your legs are asleep. Thus, it is very vital that the sciatic nerve works properly. For this reason sitting erect is necessary and the following daily exercise will be found very useful.

In the morning stand erect keeping the legs 12/15 inches apart. Raise the hands and try to go backward from the waist as much as possible inhaling at the same time. Then come forward and bend from the waist with extended hands while exhaling at the same time. It will be observed that due to improper sitting and sleeping practice, the sciatic nerve is contracted and it may not be possible to touch the ground.

However, when this exercise is repeated, you will be surprised to observe that not only are you able to touch the ground but even go further touching behind the legs. Thus, the spinal cord gets fully streched and flow of energy is ensured all over the organs.

It is observed that due to the unexpected jerks and lifting of heavy things, cold, wearing of high heeled shoes, etc. the sciatic nerve gets damaged, causing pain in the legs from waist to toes, knees, etc. There is no damage to vertebrae and so the root cause is not detected even in X-rays. However, when pressed on the points of sciatic nerve (from the ankle ball to culf muscle i.e. 5 inches) pain will be felt. After the treatment on the points of sciatic nerve in both the legs, all pain in the legs including knee pain will subside.

If you have an infection, it needs to be treated. However, you say your pain is associated with constipation and/or trapped gas which is not an infection at all. If it is caused by constipation then you need to treat the constipation. Get enough fiber in your diet everyday or supplement with a fiber tablet or powder like Metamucil or Citrucel. If gas is the problem then you need to take something for gas, like GasX, or Maalox, or some other over the counter product that helps gas. You could also try taking Advil or Tylenol for the pain.

You may be experiencing pain related to intestinal inflammation. The intestines lie atop the muscles of the back (e.g., psoas) and inflammation can spread beyond the gut into the muscle and nerves. Is the cramp/numbness relieved by defecating/passing gas? If so, it is probably just pressure on the nerve transmitted through the surrounding muscle, or some minor inflammation.

If this is a chronic problem, you should see a GI doctor about the constipation and gas. Strive for a diagnosis to rule out inflammatory bowel disease or irritable bowel disease.

Another possibility is that you have piriformis syndrome or other entrapment of the sciatic nerve by surrounding muscle. An electrophysiologist can help determine this; if this is the case, some physical therapy can alleviate the symptoms.