Study Design: Cohort. Objectives: To examine patterns of pain intensity and variability during acute spinal cord injury (SCI) rehabilitation. Setting: Large medical university in the Midwestern United States. Methods: Data were collected from the medical records of consecutively admitted patients with new (p2 months after onset), traumatic (that is, injury resulting from external forces) or non-traumatic (that is, injury resulting from disease processes) SCI. A total of 11 001 hourly pain ratings on 1709 inpatient days were collected from 56 inpatients. Multi-leveling modeling was used to test models of pain intensity, pain variability, diurnal variability and pain medication administration. Results: Pain intensity and variability decreased during the inpatient stay. Compared with those with non-traumatic injuries, those with traumatic injuries had significantly higher pain; those with American Spinal Injury Association Impairment Score (AIS) A scores had a slower decline of pain, while those with AIS D scores had a sharper decline. Pain increased from morning to evening during the latter days of the inpatient stay whereas pain was relatively stable during the early days in the inpatient stay. Those not using a ventilator at admission were significantly less likely to receive a pain medication than those who were, despite no significant differences in pain levels. Conclusion: Pain changes during acute rehabilitation, however, the moderating effect of time suggests that change is not consistent across all injury characteristics. Findings suggest that not only should pain management be individualized but it should also reflect a greater understanding of change over time.
INTRODUCTIONPain after spinal cord injury (SCI) is one of the most prevalent secondary conditions, with estimates ranging from 26 to 95% 1 with substantial impact on quality of life. [2][3][4] Unfortunately, success in treating pain after SCI remains elusive. 5,6 Prospective studies suggest that pain is relatively stable over time and does not necessarily diminish 7 and in some cases can increase in the early years postinjury. 8 Few studies address pain in the acute period following injury. 9 Some work suggests that pain emerges early in the course of recovery and that types of pain vary over time, but that prevalence does not vary by injury level or severity, 10 and is sustained into the chronic phase of injury. 11 A major criticism of pain research is the common use of retrospective methods and associated problems of recall bias. 12,13 Although recommended as a solution to minimizing bias in pain research, 14 few studies in SCI utilize momentary assessments or 'real time capture' of pain. Prospective studies often have long lags and use only a handful of assessments to extrapolate pain trajectories. Thus, the purpose of this study was to investigate hourly pain ratings from inpatients with new SCI over the course of acute rehabilitation to examine (1) the pattern of pain intensity (Q1) and variability (Q2); (2) shifts in diurnal patterns of pai...