In this paper,based on the latest domestic and foreign literatures,segmental stability in degenera-tive spondylolisthesis,therapeutic principles,indications and new progress of many minimally invasive surgery of this disease are described in detail.Minimally invasive surgical procedures for degenerative lumbar spondylolisthesis is diversity,so we should choose the best treatment for every patient according to the age,basic diseases,the degree of slipped levels,segmental stability of slipped vertebraes,ecnomic factors in patients,combined with operation skills of surgeons.

Objective To assess the clinical effect of Percutaneous transforaminal endoscopic spinal surgery for central lumbar spinal stenosis.Methods Total 92 patients (44 males and 48 females with average age of 68.6± 12.4 years) with central lumbar spinal stenosis were enrolled in our study during February 2012 and July 2016.All patients were treated with Percutaneous transforaminal endoscopic spinal surgery.Clinical and Radiographic evaluation were investigated on 1 week,3 months,6 months,12 months postoperatively and final follow-up.Visual analogue scale (VAS) for low back pain and leg pain,Oswestry disability index(ODI) for low back pain were used to evaluate the clinical efficacy of surgery.Pre and postoperative Dural sac cross sectional area(DSCA) was measured.And the correlation between changes of DSCA and clinical efficacy was analyzed.Results The operation time was 45-1 15 min.The mean operation time was 75±15 min.the mean blood loss was 15±5 ml (range 8-50 ml).All patients were followed for 12-46 months (24.5±5.3 months).VAS for low back pain,VAS for leg pain,and OD1 were significantly improved from 6.75± 1.28,7.79± 1.15 and 39.82％ ±5.06％ preoperatively to 2.21± 1.08,2.16± 1.14 and 9.82％ ±3.69％ at the latest follow-up.Dural sac cross sectional area significantly increased from 55.35±12.18 mm2 preoperatively to (102.36±15.38) mm2 at the latest follow-up.Correlation coefficient with DSCA change was-0.480 for ODI change,-0.612 for VAS(low back pain) change,-0.637 for VAS (leg pain)(P ＜ 0.05);obvious positive correlation existed between the change of DSCA and patient's clinical efficacy.It showed that the change of DSCA was positively correlated with the patient's clinical efficacy.The clinical results were excellent in 56 cases.good in 29,fair in 4,and poor in 3 based on the MacNab criteria.92.39％ demonstrated a good-to-excellent outcome.One case occurred cauterizing syndrome,3 cases of recurrence,and 2 cases of Dural tear.There was no severe vascular or nerve injury.Conclusion Percutaneous transforaminal endoscopic spinal surgery provides a new minimally invasive treatment for central lumbar spinal stenosis.It is safe and effective.It is found that the change of DSCA is positively correlated with the clinical efficacy of surgery.

INTRODUCTIONMinimally invasive surgery (MIS) is increasingly used in the treatment of lumbar stenosis. However, it is still not clear if the employment of minimally invasive surgical techniques can achieve superior clinical outcomes compared to standard open laminectomy.

MATERIALS AND METHODSAn extensive literature review regarding the clinical outcome, safety, and efficiency of MIS and standard open surgery (OS) in the treatment of lumbar stenosis was conducted on Medline, Cochrane, EMBASE, and Google Scholar databases up to 19 August 2016.

RESULTSSixteen studies that enrolled a total of 1580 patients with surgically-indicated lumbar stenosis were identified; 793 patients underwent MIS and 787 patients underwent conventional OS. No significant difference was found in the improvement of Oswestry Disability Index (ODI) (P = 0.718) and operation time (P = 0.322) between patients from different treatment groups. MIS was associated with better visual analogue scale (VAS) for back pain (P = 0.01), shorter length of hospital stay (P <0.001), and lower blood loss (P <0.001).

CONCLUSIONOur findings indicate that both MIS and standard OS can effectively manage patients with lumbar stenosis and lead to comparable clinical outcomes. Further studies are necessary to evaluate MIS with different types of conventional surgery for lumbar stenosis.