Pain drawings in the evaluation of lumbar disc-related pain

Abstract

Pain drawings have been used in a variety of settings to investigate pain, including low back pain. The drawings allow a rapidly completed assessment that have several potential applications including psychological screening tool, documenting pain location, and evaluating pain quality.

The purpose of this work was to investigate the use of pain drawings in low back pain populations with particular focus on patients suspected of having lumbar disc-related pain. More specifically, the primary objectives were to: determine the repeatability of low back pain patients in completing pain drawings, determine if the overall pain pattern indicated in the drawings was related to the pain provocation component of discography, determine if there was a relationship between the pattern of pain and/or the quality of sensation indicated by patients in pain drawings to symptomatic lumbar disc pathology identified by CT/discography, investigate the potential relationship between distal pain location and/or pain quality with respect to the severity of symptomatic lumbar disc disruption, and to determine if there was a relationship between the pattern of pain indicated in pain drawings and the specific disc level(s) identified by CT/discography to be symptomatic and disrupted.

The populations studied were being evaluated and treated by spine specialists for suspected lumbar disc-related pain. All had failed to gain adequate pain relief from conservative care and were chronic pain patients. The primary population in the repeatability study included 45 males and 21 females with a mean age of 40.6 years. In the other studies the primary population included 187 patients (118 males and 69 females) with a mean age of 37.2 years, ranging from 18 to 62 years. All the pain drawings were scored by a single evaluator. In studies involving CT/discography, all the images were scored by a different single evaluator. Low back pain patients demonstrated an acceptable level of repeatability in completing the drawings, even over a period of several months. Patients whose drawings were classified as possibly being related to psychological disturbances did report pain more often during discographic injection; although such patients did not tend to have more discs that were classified as disrupted based on imaging methods.

There was a significant relationship between the pattern of pain indicated in the drawings and the presence of symptomatic disc disruption. Also, it was found that the severity of disc disruption was not related to the distal extend of the pain indicated in the drawings. That is, patients with nonbulging or nonherniated discs were just as likely to indicate pain in the thigh and leg as were patients with more severe disc pathology resulting in deformation of the outer annular wall. However, patients with the less severe disc disruption reported more burning and aching sensations than did patients with more severe disruption. There was a significant relationship between the specific intervertebral disc level demonstrating symptomatic disc pathology and the location of the patient's pain.

This work indicates that patients are repeatable in completing pain drawings, even over a period of several months and thus it appears to be a stable evaluation instrument in this population of chronic back pain patients. The drawings also provide an easily administered evaluation, which may help identify patients with symptomatic disc pathology in the lumbar spine. They also appear to be a useful instrument in studying various aspects of low back pain.