Low back pain is one of the most common–and most costly–conditions in the U.S. Every year, about 2% of all workers suffer low back injuries on the job. Yet low back pain is one of the hardest conditions for doctors to measure and understand. Common tests, such as X-rays and MRI scans, can’t always pinpoint the underlying problem. They also don’t tell much about a patient’s level of disability.
To make matters worse, patients often don’t give a good idea of their symptoms in the doctor’s office. Consciously or unconsciously, they exaggerate their symptoms. This can happen when patients want disability status, or when they are nervous, scared of causing themselves pain, or depressed. But this makes it even harder for doctors to determine if the back condition is just painful, or if it is actually causing disability.
These researchers were looking for a way to measure spine function that isn’t consciously influenced by the patient. They studied test results of 91 patients with low back pain. Patients answered questions about their pain and their ability to do certain tasks. Patients then underwent standard tests of spine range of motion and strength. In addition, they also had a spinoscopic exam. A spinoscope measures coordination of the spine through movements of the individual vertebrae. Unlike range of motion or strength, it is nearly impossible for patients to influence these movements consciously.
Researchers then compared the results of the different kinds of tests. They found a weak relationship between disability, functional status showed by the tests, and patients’ reports of pain. Patients who rated their pain and disability highly tended to do somewhat worse on the standard range-of-motion and strength tests. However, there was a much smaller link between patients’ reports and the results of the spinoscopic examination.
The authors conclude that the weak link between the questionnaires and the functional tests means that doctors need to be careful in using patients’ self-reports to determine disability levels. They suggest that more complex measurements of spinal coordination, such as those from the spinoscope, could prove helpful in getting a better idea of patients’ disability levels.