Little is known about the pathogenetic etiology of central pain in patients with traumatic brain injury (TBI). We investigated the relation between injury of the spinothalamocortical tract (STT) and chronic central pain in patients with mild TBI.
We recruited 40 consecutive chronic patients with mild TBI and 21 normal control subjects: 8 patients were excluded by the inclusion criteria and the remaining 32 patients were finally recruited. The patients were classified according to 2 groups based on the presence of central pain: the pain group (22 patients) and the nonpain group (10 patients).
Diffusion tensor tractography for the STT was performed using the Functional Magnetic Resonance Imaging of the Brain Software Library. Values of fractional anisotropy (FA), mean diffusivity (MD), and tract volume of each STT were measured.
Lower FA value and tract volume were observed in the pain group than in the nonpain group and the control group (P < .05). By contrast, higher MD value was observed in the pain group than in the nonpain group and the control group (P < .05). However, no significant differences in all diffusion tensor imaging parameters were observed between the nonpain group and the control group (P > .05).
Decreased FA and tract volume and increased MD of the STTs in the pain group appeared to indicate injury of the STT. As a result, we found that injury of the STT is related to the occurrence of central pain in patients with mild TBI. We believe that injury of the STT is a pathogenetic etiology of central pain following mild TBI.
Department of Physical Medicine and Rehabilitation (Drs Kim, Ahn, Cho, and Jang) and Department of Neurosurgery (Dr Kim), College of Medicine, Yeungnam University, Taegu, Republic of Korea.
Corresponding Author: Sung Ho Jang, MD, Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University 317-1, Daemyungdong, Namku, Taegu, 705-717, Republic of Korea (firstname.lastname@example.org).
This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2012R1A1A4A01001873).
The authors declare no conflicts of interest.