People who suffer back pain can gain some relief by manipulating the spine a studies say. Paul G. Shekelle, M.D., Ph.D., of the West Los Angeles Veterans Affairs Medical Center, Los Angeles conducted test to find out just how effecting spinal manipulation was at this task. Of 25 trials, 15 of them showed moderate improvement. None of the trials reported any particularly adverse effects. Some reported ailments such as muscle stiffness, head ache, or pain increase. Those who conducted the study say the effect of spinal manipulation is the same as the effect for drugs.