We developed a new method of posterior lumbar interbody fusion (PLIF) using an en-bloc resected lamina with or without a hydroxyapatite block as an interbody spacer instead of auto-iliac bone, in combination with rigid-type spinal instrumentation. The purpose of this study was to evaluate the effectiveness of our method. There were 23 patients (13 males, 10 females, age at the time of operation: 21–71 years, mean 50.5 years; follow-up: 1–4 years, mean 2 years and 3 months). In 10 patients with spondylolitic spondylolisthesis and 3 patients with spondylolysis, the floating lamina was resected enbloc by mid-line splitting. In 7 patients with degenerative spondylolisthesis and 3 patients with unstable spine, a cleavage was made at the isthmus and then the complex of lamina and inferior spinous process was resected en-bloc. Seventeen patients with olisthesis underwent reduction. PLIF was performed at the L4/L5 level in 10 patients and the L5/S1 level in 13 patients. Sixteen patients with preoperative low back pain recovered, except for one patient with instability at the adjacent vertebra. All of the seven patients with preoperative gait disturbance recovered. The ratio of olisthesis changed from preoperative 30% to postoperative 18% on average. Good bony union was obtained in both the patients with and those without a hydroxyapatite spacer. Posterior lumbar interbody fusion using an en-bloc resected lamina as an interbody spacer in combination with rigid-type spinal instrumentation was useful.
Unilateral Minimally Invasive Posterior Lumbar Interbody Fusion (Unilateral Micro-PLIF) for Degenerative Spondylolisthesis: Surgical Technique
