Abstract: Objective To explore the casual relationship and the significance of identification among the injury, disease and damage consequence in the disability evaluation of lumbar spondylolysis by the standard for identifying grading of disability caused by work-related injuries. Methods The general data, injury manner, clinical treatment and the imaging examination of 32 lumbar spondylolysis cases were collected and retrospectively analyzed. According to the degree of participation in the injury and damage consequence, the identification and assessment of casual relationship was made, and the grading of disability was assessed. Results For 32 cases, injury had no effect on damage consequence in 7 cases, slight effect in 5 cases, secondary effect in 13 cases, equivalent effect in 4 cases, and complete effect in 3 cases. According to the related items in the standard for identifying grading of disability caused by work-related injuries, 3 cases were rated level 7, 5 cases were level 8, 6 cases were level 9, 11 cases were level 11 among the cases which existed causal relationship. Conclusion The formation of lumbar spondylolysis is connected to the factors of age, anatomy, occupation and injury manner etc. The degree of disability should be accessed comprehensively after the analysis of the casual relationship among the injury, disease and damage consequence.

Key words: forensic medicine, spinal fractures, lumbar spondylolysis, cases analysis