The use of patient symptoms to screen for serious back problems

Even when a patient is referred by a physician, the physical therapist must remain alert to the possibility that the patient may require medical care outside the realm of physical therapy. Physical therapists must be able to screen low back pain patients to identify those who have serious low back problems which require additional diagnostic evaluation and treatment by a physician. It is important for physical therapists to know which symptoms and signs or combination of symptoms and signs best indicate the likelihood of a serious problem. The purpose of this study was to test the sensitivity and specificity of low back pain symptoms in distinguishing individuals with a benign low back problem from those requiring surgical or medical intervention. Demographic and clinical data were collected retrospectively from a standardized low back pain questionnaire located in the medical records of 174 low back pain patients. Patients were classified as having a benign low back problem (N = 41) or a serious low back problem (N = 133) based on surgical findings or long term follow-up. Some individual symptoms had high specificity, but none had high sensitivity. To improve sensitivity while attempting to maintain moderate specificity, a number of symptoms were considered in parallel. The highest combination of sensitivity (.87) and specificity (.50) was obtained by combining in parallel the symptoms of unable to sleep, awakened and unable to fall back to sleep, medication required to sleep, and pain worsened by walking.