Relationship between Soft Tissue Damages and Spinal Cord Injury in Lower Cervical Spine Trauma

Song, Kyung Jin; Lee, Kwang Bok; Hwang, Byung Yun; Lim, Young Jin; Yoon, Jin Ho

Abstract

PURPOSE
To determine the implications of soft tissue damage and to evaluate the correlations between the extent of soft tissue damages and spinal cord injury after a lower cervical spine trauma. MATERIALS AND METHODS: This study analyzed the medical records, plain radiograms, and MRI of the consecutive 89 patients who underwent operative treatment in the lower cervical trauma. The radiological parameters of soft tissue damage including anterior longitudinal ligament (ALL), intervertebral disc (Disc), posterior longitudinal ligament (PLL), ligamentum flavum (LF), interspinous ligament (ISL), supraspinous ligament (SSL), posterior muscle group (PM), cord compression (CC), and cord signal changes (CS) were evaluated using plain radiograms and magnetic resonance imaging. The relationship between the level of cord injury and the type of soft tissue damage, injury type and severity was determined. RESULTS: There was a significant correlation between the extent of cord injury and the injury type. Cord injury frequently occurred as a result of compressive extension (3 of 4 cases), combined injury (4 of 7 cases) and distractive extension (14 of 23 cases). On the other hand, only 11 of the 16 cases with compressive flexion had a cord injury. In the distractive-extension cord injury cases (2 out of 10 cases in stage I, 12 out of 13 cases in stage II) the frequency of cord injury increased with increasing degree of the soft tissue damage. The incidence of cord injury was higher in the distractive-flexion cases (stage I, 0 out of 6 cases, stage II, 8 out of 35 cases, stage III, 3 out of 5 cases), (p=0.082). Multiple logistic analysis revealed a significant correlation between the cord injury and soft tissue damage including parameters such as the injury type, PLL injury, CC and CS. There was more frequent cord injury encountered in patients with more extensive injuries to the posterior neck muscles (p=0.063). CONCLUSION: There was a significant correlation between the injury type and the incidence of cord injury. In distractive extension and distractive flexion, there was more increasing incidence of cord injury with increasing severity of the injury. In addition, there was a high incidence of cord injury associated with not only the injury type but also a PLL and posterior neck muscle injury.