Pain type and intensity in long-term spinal cord injury

Abstract

Background. Pain is one of the most common secondary symptoms seen in patients with spinal cord injury (SCI). Approximately 65 to 85 % of all SCI patients complaining of pain, with a third having severe/excruciating pain. Despite a large number of studies, some aspects that are fundamental for the choice of pain therapy remain practically unexplored. The purpose of our study was to determine the types, subtypes, and intensity of pain in subaxial cervical spine SCI patients. Materials and methods. We performed a retrospective analysis of the patients’ database admitted in Romodanov Neurosurgery Institute of National Academy of Medical Sciences of Ukraine from 2010 to 2020 with subaxial cervical spine traumatic injury. The patients’ state was assessed within 12–18 months after the injury. We determined the functional class of neurological disorders using the ASIA scale. Pain sensation was characterized using International Spinal Cord Injury Pain Classification. The Numeric Rating Scale was the instrument for pain intensity assessment. Results. Persistent pain sensations in 12–18 months after subaxial cervical SCI are recorded in 86.42 % of 81 analyzed victims, whereas one subtype of pain is noted in 38.57 % of all patients with pain, two subtypes — in 40 % and three — in 21.43 % subjects. Elements of nociceptive pain were registered in 54.32 % of all patients, and neuropathic pain was recorded in 71.6 % of cases. When assessing pain subtypes, musculoskeletal pain was observed in 54.32 % (95% CI: 44.44–66.16) of all subjects, neuropathic pain at the trauma level in 51.85 % (95% CI: 41.98–63.77), and neuropathic pain below the trauma level was noted in 43.21 % patients (95% CI: 33.33–54.91). Nociceptive visceral and other neuropa-thic types of pain were reported sporadically — in 4.94 % (95% CI: 1.23–9.09) and 3.7 % (95% CI: 1.23–7.94) patients, respectively. When comparing the nature of pain and the ASIA functional class, we determined that the frequency pattern of the pain distribution statistically significantly correlates with the level of neurological disorders. The greatest intensity of pain was observed in patients with the ASIA functional class C of neurological disorders. Conclusions. The obtained results allowed us to reveal the regularities of the clinical picture in patients with different levels of neurological disorders, which is of practical importance for the development of optimal pharmacological treatment schemes.