Evaluation of neck pain by using a visual analog scale before and after laminoplasty in patients with cervical myelopathy: relationship with clinical results

OBJECT: In this study the authors investigated the neck pain of patients with cervical myelopathy by using a visual analog scale (VAS) before and after laminoplasty, and they analyzed the association of amount of neck pain with the clinical results. METHODS: A retrospective review was conducted in 41 patients with cervical myelopathy who underwent cervical laminoplasty. The patients were assessed using questionnaires to evaluate the neck pain intensity before surgery, and 2 years after surgery, the outcome was assessed using a VAS. The degree of cervical lordosis and range of motion (ROM) of the cervical spine were evaluated before and after laminoplasty. The neurological status was also evaluated before and after surgery. RESULTS: The patients were classified into 2 groups according to their preoperative neck pain: 1) the pain (PA) group, which included patients whose preoperative VAS score was more than 1 mm; and 2) the no pain (NP) group, which included patients whose preoperative VAS score was 0 mm. Inclusion in the PA group indicated a restriction of the cervical ROM before laminoplasty; however, the improvement of neck pain in this group and the deterioration of pain status in the NP group eliminated this difference after laminoplasty. Thereafter, the PA group was classified into 2 subgroups according to the improvement of the preoperative neck pain: 1) the improved group, which included patients whose postoperative VAS score decreased; and 2) the no improvement group, which included patients who were not in the improved group. No significant differences were observed in the average recovery and radiographic results between these 2 subgroups. CONCLUSIONS: Neck pain before surgery in the PA group indicated a restriction of the cervical ROM; however, the improvement of neck pain in this group and the deterioration of pain status in the NP group indicated the disappearance of this difference postoperatively. Moreover, improvement of preoperative neck pain was not associated with the radiographic results and the neurological recovery rate.