Abstract
BACKGROUND: Microscopically assisted posterior lumbar fenestration plays a critical role in spinal surgery, yet no animal model currently replicates this procedure. OBJECTIVE: This study aimed to rigorously simulate clinically relevant microscopically assisted posterior lumbar fenestration in New Zealand white rabbits, establishing a stable animal model for investigating postoperative recurrence and pathophysiological mechanisms, while evaluating its feasibility. MATERIALS AND METHODS: Forty-eight 4-month-old male New Zealand white rabbits (weight: 2.0-2.5 kg) were randomly assigned using a number table. Preoperative assessments included general nutritional status and response to stimuli. Intravenous anesthesia was administered, followed by localization of the L5-6 interlaminar space, skin preparation, and disinfection. Under microscopic guidance, partial laminectomy and ligamentum flavum resection were performed using 2.0-mm rongeurs, with successful exposure of the dura mater and nerve roots defined as procedural success. Anesthetic depth was evaluated using the Definition of the Anesthetic States and Attributed Numerical Scale. Vital signs (Peripheral Oxygen Saturation, respiratory rate, temperature, heart rate), intraoperative blood loss, surgical duration, and anesthesia time were monitored. Micro-CT scans were conducted preoperatively and on postoperative day 1, with laminotomy area measured coronally to confirm success. Data were analyzed using SPSS and R software (statistical significance: p < 0.05). RESULTS: Anesthesia success rate: 93.75%;Surgical success rate: 95.56%༛Model success rate: 89.58%. Micro-CT demonstrated significant laminotomy area enlargement (preoperative: 10.01 ± 1.10mm2, postoperative: 31.86 ± 2.05mm2 (p<0.001). Vital signs (heart rate, respiratory rate, temperature; p < 0.05) correlated closely with anesthesia. The learning curve analysis revealed average slopes of - 0.84 (EG-1 to EG-20) and - 0.23 (EG-21 to EG-48), indicating improved surgical efficiency with experience. CONCLUSION: This study successfully established a highly reproducible rabbit model of microscopically assisted posterior lumbar fenestration, characterized by a gentle learning curve. The model provides a robust platform for investigating pathological mechanisms of spinal disorders treated via this approach.