probably not. the area you're describing the back of the thigh consists of a trio of muscles we call "the hamstring. " what you're describing sounds like a common spasm or cramp of the hamstring. this can happen for various reasons -- or no reason at all. the hamstring would be an uncommon place for a deep vein thrombosis to arise particularly in the absence of any other contributing factors (such as recent joint replacement surgery). muscle cramps in general can signal dehydration or even a mild potassium deficiency so you could try drinking more water or eating a banana (assuming your not allergic) to see if that helps the situation. if the cramping doesn't clear up on its own you certainly can put a call in to your primary health care provider for an appointment to have this evaluated. hope this helps!
i am having a sharp spasm like pain in the back of my left leg about 5 inches above the knee. should i be concerned.