Metrx quadrant system in the surgery of lumbar spondylolisthesis: preliminary clinical application

To evaluate the clinical efficacy and minimal invasiveness of quadrant posterior distraction system in the posterior lumbar spondylolisthesis (LS) surgery. Sixty-one LS patients were randomly divided into two groups: quadrant posterior minimally invasive surgery system as invasive group (n = 30) and traditional open surgery as open group (n = 31). The clinical outcome of pain relief was assessed by the scoring systems of visual analogue scale (VAS) and Oswestry disability index (ODI) for low back pain. Radiographic assessment: preoperative and 1-day, 3-month and last follow-up (12 months) radiographs were analyzed including the index of relative posterior disc height. The scores of VAS and ODI of invasive group were less than open group at Months 3 and 12 post-operation (P < 0.01). Relative posterior disc height of intra-operation and Month 3 was not significantly different (P > 0.05). And there was only statistical significance difference within 12 months (P < 0.05). At Month 12 post-operation, the fluctuating rate was slight. The minimally invasive operation with Quadrant is less traumatic to the patients than traditional open operation in the protection of spinal stability, postoperative rehabilitation and radiographs. This new minimally invasive spine technique should be popularized.