Table 1. Characteristics of the study population (n=281).

CSM, cervical spondylotic myelopathy; LP, laminoplasty; PDF, posterior spinal decompression and fusion surgery; ADF, anterior spinal decomression and fusion surgery; OPLL, ossification of the posterior longitudinal ligament; CDH, Cervical disc herniation; CSA, cervical spondylotic, cervical spondylotic amyotrophy; VF, vertebral fracture; VP, vertebroplasty; OYL, ossification of the yellow ligament; PD, Posterior decompression surgery; LSS, lumbar spinal stenosis; DS, degenerative lumbar spondylolisthesis; LDH, lumbar disc herniation.