The design and clinical application of MED-TLIF with mobile microendoscopic discectomy technique / 天津医药

ABSTRACT

Objective To evaluate the feasibility and clinical efficacy of microendoscopic discectomy-transforaminal lumbar interbody fusion (MED-TLIF) with mobile microendoscopic discectomy (MMED) technique. Methods The MMED includes outer working canal and inner operating canal. Large working canals and endoscopic chisel were fabricated for MMED-TLIF,which was designed as followthe pedicles and index level were located with fluoroscopy, and a 2.5 cm incision was made between pedicle punctures sites on the symptomatic side. Working canal was inserted, and the facet was exposed,the inferior articular process and medial part of superior articular process were resected. The disc and cartilage endplates were curettage, and the intervertebral space was released and tested. The inner operating canal was removed and the interbody space was grafted and supported with suitable cage. Percutaneous pedicles screws were inserted and the residual displacement was evaluated under fluoroscopy, followed by the install of connecting rods for reduction and fixation. Fifty-six patients with lumbar stenosis including 32 cases of instability and spondylolisthesis (1 degree in 15 cases and 2 degree in 9 cases) were treated with this technique. The ODI index and VAS score were compared in patients before and after surgery. The efficacy was evaluated by Macnab standard. Results Surgery was successful in all patients, with no nerve injury or conversion to open surgery. The mean operative time was (120±30) min (range, 90–180 min),with a mean blood loss of (120±50) mL (range,50–200 mL). The post-operative X-ray and CT scans showed improvement of spinal alignment with mean reduction ratio of 72%. Patients were followed up for 6 to 36 months. The ODI score decreased from 50.1±11.2 to 5.8±5.6. The VAS score of lumbar decreased from 7.1±4.2 to 1.2±1.0 and VAS score of leg decreased from 4.1±2.5 to 1.1±0.9 at final follow-up. The clinical results were excellent in 36 cases,good in 20 according to the Macnab scale. Conclusion MED-TLIF can easily perform with MMED technique,with sufficient decompression and reduction, and providing satisfactory results with less invasive procedure.