Abstract: 【Abstract】Objective: To observe the clinical results of a pedicle screw- lamina hook system applied to treat the lumbar spondylolysis without spondylolisthesis.Method: Since august, 2005, 10 cases of lumbar spondylolysis without spondylolisthesis have been treated with a pedicle screw- lamina hook system.Eight cases is male,tow cases is female.The mean age of the group was 22, from 18to 26.Tow cases of spondylolysis located at L2,one case at L3,three cases at L4,four cases at L5.All the patients suffered from severe back pain for more than six months.The average VAS before the operation was 7.2.During the operation, the presence of the pars interarticularis defect was confirmed.The defects were cleared of any fibrous and cartilaginous tissues.The sclerotic bone margins were curetted until bleeding was noted.Autograft havested from posterior ilium was done.The pedicle screw- lamina hook system was placed onto the index vertebra.Result: All the patients were followed- up for more than 18 months ( 12～36months) .The significant back pain relief was found in all the cases.The postoperative VAS was 2.2. The bony healing was comfirmed in 10 cases.Conclusion: The simple spondylolysis in youth can be treated by the pedicle screw- lamina hook system without spinal fusion.The pedicle screw- laminahook system is proved to be safe and effective.

Key words: Lumbar spine, Spondylolysis, Repair of lumbar spondylolysis