Brief Answer: Due to neural cause. Detailed Answer: Hello, Thanks for posting your query. I can understand your concern for these symptoms. It is good that all the investigation reports have come out clear but from your symptoms it looks like parasthesia of the lower limbs. Even if the investigations are normal, still the nerve involvement symptoms may be there due to soft tissue swelling or due to inflammation in the nerve itself. These neural pains are a challenging thing to treat as careful examination is needed to ascertain the level of nerve involvement. Anxiety and panic attacks can also cause numbness or burning sensations. The left heel pain is not likely to be related to this. It can happen due to plantar fasciitis. Many other causes of such sensations are there. These include injury to the back or spinal cord, Lack of blood supply to the legs as a result of plaque formation in the blood vessels, diabetes, stroke, multiple sclerosis and underactive thyroid. Abnormal levels of calcium, potassium, or sodium in your body and a lack of vitamin B12 can also cause numbness or burning sensations. Firstly, I’ll request you to get your blood sugar/HbA1c (glycated hemoglobin) tested to rule out Diabetes mellitus. Also get your thyroid hormones levels evaluated. You can take some vit B12 for some days and see if the symptoms improve. I hope this answers your query. In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out. Wishing you good health. Regards, Dr. Praveen Tayal. For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Praveen-Tayal

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