Objective To investigate the effectiveness of posterior intrasegmental fixation with pedicle screw-lamina hook system and bone grafting for lumbar spondylolysis. Methods Between January 2005 and October 2009, 22 patients with lumbar spondylolysis underwent posterior intrasegmental fixation with pedicle screw-lamina hook system and bone grafting. There were 19 males and 3 females with an average age of 18.4 years (range, 12-26 years). The main symptom was low back pain with an average disease duration of 16 months (range, 8-56 months). The visual analogue scale (VAS) was 6.0 ± 1.2 and Oswestry disability index (ODI) was 72.0% ± 10.0% preoperatively. The X-ray films showed bilateral spondylolysis at L4 in 9 cases and at L5 in 13 cases. The range of motion (ROM) at upper and lower intervertebral spaces was (11.8 ± 2.8)°and (14.1 ± 1.9)°, respectively. ResultsAll incisions healed by first intention. All patients were followed up 12-45 months (mean, 25 months). Low back pain was significantly alleviated after operation. The VAS score (0.3 ± 0.5) and ODI (17.6% ± 3.4%) were significantly decreased at last follow-up when compared with preoperative scores (P lt; 0.05). CT showed bone graft fusion in the area of isthmus defects, with no loosening or breaking of internal fixator. At last follow-up, the lateral flexion-extension X-ray films of the lumbar spine showed that the ROM at upper and lower intervertebral spaces was (12.3 ± 2.1)°and (13.5 ± 1.7)°, respectively; showing significant differences when compared with preoperative values (P lt; 0.05). Pain at donor site of iliac bone occurred in 1 case, and was cured after pain release treatment. ConclusionThe posterior intrasegmental fixation with pedicle screw-lamina hook system and bone grafting is a reliable treatment for lumbar spondylolysis, having a high fusion rate, low complication rate, and maximum retention of lumbar ROM.