Study design: This was a retrospective case series.
Objective: To retrospectively evaluate the clinical outcome of microendoscopic decompression for lumbar spinal stenosis (LSS) including an evaluation of the extent of decompression using computed tomography.
Summary of background data: Microendoscopic decompression has been a widely applied procedure to treat LSS with satisfactory outcomes and comparatively fewer complications and revision. However, few reports showed computed tomography (CT) measurements of the lumbar spine to assess the postoperative decompression.
Methods: This study included 103 patients (55 males and 48 females; mean age, 69 y) who underwent microendoscopic decompression for treatment of LSS between January 2009 and January 2011. All patients underwent preoperative CT and postoperative CT at 6 months and 2 years of follow-up to measure the vertebral canal area and the sagittal diameter of the lateral recess at the outer rim. The Japanese Orthopedic Association (JOA) scale, Oswestry Disability Index, and Visual Analogue Scale were used to evaluate clinical efficacy.
Results: The mean vertebral canal area and sagittal diameter of the lateral recess were significantly larger at 6 months and 2 years after surgery compared with 1 day before surgery (P<0.001). The mean JOA scale scores were significantly higher at 6 and 24 months following surgery compared with before surgery (P<0.001). The mean Oswestry Disability Index scores and Visual Analogue Scale scores at 6 months and 2 years after surgery were significantly lower compared with before surgery (both P<0.001). The mean JOA recovery rates at 6 months and 2 years of follow-up were 61% and 64.3%, respectively.
Conclusions: The results confirm that microendoscopic decompression for LSS is safe and effective. This study is one of the first to obtain CT measurements of the lumbar spine to assess the postoperative decompression of this procedure.