A longitudinal study of the prevalence and characteristics of pain in the first 5 years following spinal cord injury

Abstract

A longitudinal cohort study of 100 people with traumatic spinal cord injury (SCI) was performed to determine the prevalence and severity of different types of pain (musculoskeletal, visceral, neuropathic at-level, neuropathic below-level) at 5 years following SCI. Prospective data on the characteristics of pain up to 6 months following injury had been collected previously and allowed comparisons between the presence of pain at different time points. In addition, we sought to determine the relationship between the presence of pain and physical factors related to the injury such as level of lesion, completeness and clinical SCI syndrome. We also obtained information regarding mood, global self-rated health and the impact of pain on function. Of the 100 subjects in the original cohort, 73 were available for follow up. When all types of pain were included, 59 of the 73 subjects (81%) reported the presence of pain. Musculoskeletal pain was the most common type of pain experienced and was present in 43 subjects (59%), at-level neuropathic pain was present in 30 subjects (41%), below-level neuropathic pain was present in 25 subjects (34%) and visceral pain was present in four subjects (5%). Overall, 58% reported their pain as severe or excruciating and those with visceral pain were most likely to rate their pain in these categories. There was no relationship between the presence of pain overall and level or completeness of lesion, or type of injury. However, tetraplegics were more likely to report below-level neuropathic pain. This study prospectively demonstrates the differing time courses of different types of pain over the first 5 years following SCI. There was a strong correlation between the presence of both types of neuropathic pain at 5 years and earlier time points but both visceral pain and musculoskeletal pain demonstrated a poor correlation between time points. Chronic visceral pain occurs in a small percentage of patients and does not correlate with the presence of visceral pain early following injury. Those with neuropathic pain early following their injury are likely to continue to experience ongoing pain and the pain is likely to be severe. In contrast, chronic musculoskeletal pain is more common but less likely to be severe and cannot be predicted by the presence of pain in the first 6 months following injury.