BACKGROUND: Percutaneous laser disc decompression (PLDD) and automated peroutaneous lumbar discectomy (APLD) have been widely used in the treatment of lumbar intervertebral disc prolapse.OBJECTIVE: To compare the symptoms and improvements of patients after receiving PLDD and APLD and analyze the characteristics of the two operations.DESIGN: A non-randomized concurrent controlled observation.SETTING: The 474 Hospital of Chinese PLA.PARTICIPANTS: Totally 106 inpatients with lumbar and leg diseases of different extent were selected from the 474 Hospital of Chinese PLA as the subjects. The patients were divided into APLD group( n =46) and PLDD group( n = 60) according to different intervention measures.INTERVENTIONS: APLD group: The dilating tube was probed at different levels, and working cannula of 4.8 mm was retained at last. The fenestration was made at the fibrous rings with the trepan, then nucleus pulposus of about 1 - 5 g was clipped by the pliers for nucleus pulposus. Electric discectomy apparatus was used to aspirate the nucleus pulposus of about 0.5 - 1.5 g at 600 - 300 rounds per minute. The electric discectomy apparatus and working cannula were pulled out after operation. PLDD group: The stylet was removed and optical fibers were inserted with the naked front segment (5 mm) com pletely going beyond the needle end. Cautery was made with 15 W laser for 1 s once a time at the interval of 4 s. The total output power of laser was adjusted between 1 200 - 1 700 joules. The patients lay at supine position to be examined for pain relief and functional recovery, and then they were sent back to the ward with flatbed cart for bed rest of 3 days. Therapeutic effects were evaluated according to modified Macnab' s criteria. The curative effect was presented as percentage.operations.excellent(47.8% ), 18 good(39. 1% ), 5 passable (10.9%), and 1 poor APLD group, there were 29 cases of excellent(48.4% ), 20 good (33.3%), 9 passable (15.0%), and 2 poor(3.3% ), with 81.7% excellent the two groups. Pain in the lumbar part usually sustained for several days,then was relieved and disappeared gradually. One patient in APLD group had infection of intervertebral disc. No complications occurred in PLDD group.CONCLUSION: PLDD and APLD do not differ significantly in excellent and good rate of treating prolapse of lumbar intervertebral disc. Compared with APLD, PLDD is a more convenient and minimally invasive technique causing fewer complications.