Immediate Effects of a Spinal Lumbar Manipulation

Non-specific low back pain is defined as a pain with no specific vertebral-related cause, such as infectious disease, tumor, osteoporosis, fracture, structural abnormality, inflammatory disease, radicular compressive syndrome or cauda equine syndrome. Non-specific low back pain is a common disease in many countries. This musculoskeletal disorder is costly to public health systems. Therefore, the use of manual therapies is important in the treatment of this disease and studies show the effectiveness of this type of therapy. Spinal manipulation is applied in manual therapies such as Osteopathy, Chiropractic and Physical Therapy and is widely used for acute and chronic non-specific low-back pain. There is moderate evidence that spinal manipulation is superior to sham spinal manipulation for improving short-term pain and function in chronic and acute non-specific low back pain. However the therapeutic mechanisms involved in this procedure are not well understood. Furthermore, while the high velocity and low amplitude spinal therapy has been shown to be effective in reducing pain and improving functional capacity in subjects with non-specific low back pain, the effect on postural variables have not been investigated. Therefore, the aim of this study is to evaluate the acute effect of lumbar manipulation on pain and postural variables. Twenty-four individuals with non-specific low back pain will be randomly allocated to two groups. The intervention group will receive high velocity and low amplitude spinal therapy, while the control group will receive sham manipulation. Immediately before and after the respective manipulation protocol, both groups will be evaluated regarding pain level, using a visual-analogue scale and algometer, and postural variables, using center of pressure displacement measured with the aid of a force plate. While the patient and therapist manipulator will be aware of the protocol applied in each case, the evaluator will be blind. A statistical tre