Fig. 2

Lumbar endoscopic unilateral laminotomy bilateral decompression performed on a 51-year-old female patient diagnosed with L4-L5 lumbar spinal stenosis without degenerative spondylolisthesis or deformity. a and b preoperative anteroposterior and lateral plain radiographs; c and d preoperative flexion and extension radiographs; e and f preoperative magnetic resonance imaging scans; g preoperative computed tomography (CT) scans; h undercutting of the ipsilateral and contralateral cranial lamina was performed; i the ipsilateral and contralateral ligamentum flavum (LF) was identified and removed piecemeal with endoscopic punches and forceps; j the bipolar radiofrequency electrocoagulator was used for hemostasis; k adequate decompression of the ipsilateral and contralateral traversing nerve root (NR) and the dural sac (DS); l CT scans one week after the surgery