9Hatvigsen J,Bakketeig LS,Leboeurf-Yde C,et al. The association between physical workload and low back pain clouded by the"heahhy worker"effect[J]. Spine,2001,26: 1788-1793.
10Yong-Jun Wang,Qi Shi,WW Lu,et al. Cervical Intervertebral Disc Degeneration Induced By Unbalanced Dynamic and Static Forces: A Novel in Vivo Rat Model[J]. Spine,2006,31(14): 1532-1538.
