Muscular and Neurological Problems

Last year my husband began having tingling sensations in his right arm and leg. Numbness, muscle spasms and tingling sensations became more frequent over time. Then his neck began hurting him. The first Neurologist thought he had early signs of MS (his mother has MS.) Not satisfied he visit a second Neurologist who told him she was not sure but thought he had some form of neuropathy. I encouraged him to get a 3rd opinion in the last few months. After additional tests and MRI's they recognized he has significant atrophy on his right side. We discovered ourselves he has inflamation (inflammation) in his lower right leg. In the last six months he has lost 10 pounds. They just conducted a muscle biopsy and the initial results are inconclusive. In the last month his neck and back discomfort has gotten significantly worse. For an incredibly fit man he is now easily exhausted with his neck and back getting really stiff with any sort of physical work. The next available appt. with the Neurologist is three months out. Everything I have read on ALS matchs the inital signs. Should I request that further tests rules ALS out? Are there other conditions that have similar symtoms (symptoms)? I don't want to lose three months on my husband's life.