Microscope-assisted minimally invasive anterior lumbar discectomy and zero-profile fusion for lumbar degenerative diseases / 中华骨科杂志

ABSTRACT

Objective:To evaluate the value and efficacy of microscope-assisted minimally invasive anterior lumbar discectomy and zero-profile fusion (ALDF) for lumbar degenerative diseases.Methods:Anterior lumbar distractors were designed to maintain the distraction of intervertebral space and expose the posterior edge of the intervertebral space. From June 2018 to December 2020, 41 cases of lumbar degenerative diseases were treated with this operation, including 19 men and 22 women, aged 29-71 years old (average 42.1 years old). All patients had intractable low back pain. Imaging examination showed lumbar disc degeneration with narrow intervertebral space, including disc herniation with Modic changes in 7 cases, spinal stenosis with instability in 16 cases and spondylolisthesis in 18 cases. The involved levels included L 2,3 in 1 case, L 3,4 in 3 cases, L 2-L 4 in 1 case, L 4,5 in 17 cases and L 5S 1 in 19 cases. An incision was taken that was pararectus for L 2-L 4 and transverse for L 4-S 1, with the intervertebral disc exposed via extraperitoneal approach. The intervertebral space was released and distracted after discectomy in intervertebral space, and self-made distractors were used to maintain the space. Under microscope, the herniation, posterior annulus and osteophyte were removed for sufficient decompression, with a suitable self-anchoring cage implanted into the intervertebral space. The visual analogue score (VAS), Oswestry dysfunction index (ODI), intervertebral space height, lordosis angle and spondylolisthesis rate were evaluated. Results:Operations were performed successfully in all the patients. The operation time was 70-120 min with an average of 90 min, and the intraoperative blood loss was 15-70 ml with an average of 30 ml. No severe complication such as nerve or blood vessel injury occurred. The patients were followed up for 12 to 36 months, with an average of 18 months. At the last follow-up, VAS decreased from 6.4±2.3 to 1.1±0.9, and ODI decreased from 44.9%±16.9% to 5.8%±4.7%. Intervertebral space height recovered from 7.2±2.8 mm to 12.1±2.1 mm and lordosis angle recovered from 6.9°±4.8° to 10.1°±4.6°. X-ray showed significant recovery of intervertebral space height, lordosis angle and spondylolisthesis rate, with obvious interbody fusion and no displacement of cage. For 18 patients of spondylolisthesis, the slippage recovered from 16.6%±9.3% to 7.6%±5.3%, with an average improvement of 54.2%.Conclusion:Microscope-assisted minimally invasive ALDF can provide sufficient decompression and zero-profile fusion for lumbar degenerative diseases with satisfactory results during short-term follow-up.