Pathogenesis of Chronic Pain

Abstract

Mr. Thompson, a 46-year-old school custodian, has always enjoyed his work and has an excellent work attendance record. While lifting a large bucket of water, he developed excruciating back pain that radiated down his leg and felt that he “couldn’t stand up straight.” He left work and went home to bed, but noticed numbness in his big toe the next morning, as well as persistent back pain. He was unable to sit up in bed and needed his wife’s assistance to get out of bed. Mr. Thompson saw his doctor, who diagnosed a herniated lumbar disc with an L5 radiculopathy. Mr. Thompson proceeded to have surgery and noticed some decrease in numbness postoperatively. He and his wife were told by the surgeon that the surgery was a success. At a follow-up visit with the surgeon 1 month later, Mr. Thompson reported persistent, disabling pain. Physical examination showed good muscle strength and reflexes, and appropriate sensation in his legs. Forward flexion of the back was moderately decreased, and the muscles next to the spine were increased in bulk and tender to gentle palpation. Repeat magnetic resonance imaging and electromyographic testing were unremarkable. The surgeon provided a book showing back exercises and suggested that Mr. Thompson return to work when he felt ready. Three months after surgery, Mr. Thompson saw his family doctor, who read the surgeon’s notes of good neurological outcome from the procedure. Mr. Thompson, however, continued to report persistent pain. He reported an inability to do the exercises because of pain and had not returned to work. Mr. Thompson spent the day watching television and had discontinued all household chores. Mr. Thompson noted that his wife was “just an angel,” bringing him his meals in bed and helping him dress. He asked the primary care physician (PCP) for a note to continue staying home from work. Mr. Thompson was advised to begin his exercise program and return to work part time. A follow-up appointment was made in 3 months. Six months after surgery, Mr. Thompson continued to report persistent pain, as well as irritability and frustration over continued pain and disability. He remained sedentary throughout the day and had not returned to work. Mr. Thompson came to the appointment with a disability form and a request for handicapped parking. His wife frequently adjusted pillows behind his back and carried a drink for him. Repeat examination and review of testing again revealed no obvious pathology. The PCP became suspicious of symptom magnification and secondary gain and ordered a psychological evaluation.