Abstract: Objective To study the effects of surgical decompression,posterior lumbar interbody fusion and pedicle screw fixation for the treatment of lumbar degenerative diseases.Methods There were 44 patients who were treated with laminectomy,discectomy,nerve root loosening,posterior lumbar interbody fusion and pedicle screw fixation between the years 2000 and 2005.Of these were 18 males and 26 females,aging from 33 to 72(with a mean age of 49.2).The patients included 36 disk hernation,8 spondylolisthesis and 17 combined lumbar stenosis.For the treatment,35 patients were carried on operation of single interbody fusion and 9 with two interbody fusion and the follow-up investigation lasted for 1～5 years.Clinical status was evaluated by the Japanese Orthopaedic Association(JOA) score preoperation and at 3,6,12,24,36,48,60 months postoperation.The fusion rate was evaluated by lumbar X-ray.Results Fusion rate was 95.5% on the first year postoperatively.JOAscore of follow-up investigations increased significantly than that of preoperation,the average space between disks postoperation decreased significantly than that of preoperation,but it has lost when compared the height of disk postoperation with follow-up after surgery.Conclusion Surgical decompression,postural lumbar interbody fusion and pedicle screw fixation is an effective method for the treatment of lumbar degenerative diseases.

Key words: lumbar degenerative diseases, pedicle screw fixation, PEEK cage, posteral lumbar interbody fusion