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,lupus,motor neuron disease and underactive thyroid. Abnormal levels of calcium, potassium, or sodium in your body and a lack of vitamin B12 can also cause tingling in the knee and legs.
You can take multivitamins for some time. Also get your blood sugar tested.
My opinion is to get yourself examined by a neurologist.