The injury mechanism of traumatic cervical spine injury varies, and Allen et al. divide cervical spine injuries into 6 types based on the direction of external force at the time of injury. In this report, we present 2 cases as Lateral Flexion Stage 2. A 51-year-old male (Case 1) was injured in a traffic accident. His conscious level was JCS III-200, and he was found to have a Frankel Grade of B. X-ray revealed a C5/6 fracture dislocation injury of Lateral Flexion Stage 2. We were unable to obtain good reduction. We planned to perform posterior fusion using a cervical spine pedicle screw but could not perform the procedure due to the patient’s poor general condition. A 32-year-old male (Case 2) was injured as a result of being hit by a steel sheet. He had Frankel Grade D paralysis. X-ray revealed a C5/6 fracture dislocation injury of Lateral Flexion Stage 2. We did not perform manual reduction. We performed posterior fixation, anterior decompression and anterior fixation. Bone union was confirmed, and the patient was able to return to work. In cases of this type of fracture dislocation of the cervical spine, the supporting structures of the spinal column circumferentially rupture and induce high instability. Since closed reduction is sometimes difficult and involves risk, strong internal fixation might be recommended.

The injury mechanism of traumatic cervical spine injury varies, and Allen et al. divide cervical spine injuries into 6 types based on the direction of external force at the time of injury. In this report, we present 2 cases as Lateral Flexion Stage 2. A 51-year-old male (Case 1) was injured in a traffic accident. His conscious level was JCS III-200, and he was found to have a Frankel Grade of B. X-ray revealed a C5/6 fracture dislocation injury of Lateral Flexion Stage 2. We were unable to obtain good reduction. We planned to perform posterior fusion using a cervical spine pedicle screw but could not perform the procedure due to the patient’s poor general condition. A 32-year-old male (Case 2) was injured as a result of being hit by a steel sheet. He had Frankel Grade D paralysis. X-ray revealed a C5/6 fracture dislocation injury of Lateral Flexion Stage 2. We did not perform manual reduction. We performed posterior fixation, anterior decompression and anterior fixation. Bone union was confirmed, and the patient was able to return to work. In cases of this type of fracture dislocation of the cervical spine, the supporting structures of the spinal column circumferentially rupture and induce high instability. Since closed reduction is sometimes difficult and involves risk, strong internal fixation might be recommended.