Visual analog scales for interpretation of back and leg pain intensity in patients operated for degenerative lumbar spine disorders.

Abstract

A prospective observational study of visual analog scale (VAS) scores for pain in patients operated at one institution within the framework of a national registry. To describe the use of recording VAS for pain intensity in patients operated on for lumbar spine problems. There is no consensus regarding pain outcomes assessment in spine patients. Pain intensity, recorded on a VAS, is one of the most used measures. Still, many aspects of its interpretation are still debated or unclear. A total of 755 consecutive patients, mean age 50 years (range, 15-86 years), operated from 1993 to 1998 were included in the study; there were 420 males and 335 females. Diagnoses included herniated nucleus pulposus (45%), central stenosis (19%), lateral stenosis (14%), isthmic spondylolisthesis (9%), and degenerative disc disease (9%). Local pain, radiating pain, analgesic intake, and walking ability were recorded before surgery and at 4 and 12 months after surgery. The patients' opinions regarding the change in pain and satisfaction with the result were assessed separately. Correlation among variables reflecting perceived pain was sought. Preoperative VAS mean values for local and radiating pain were significantly different in the five diagnostic groups. Significant but moderate correlation between different types of pain outcomes and with patient satisfaction was present in all cases. Measuring pain intensity with VAS is a useful tool in describing spine patients. In the search for a standard in the evaluation of pain as an outcome, the differences between the various methods should be taken into account.