Bilateral pedicle screw instrumented extreme lateral interbody fusion for the treatment of lumbar spondylolisthesis

English Keywords:Lateral interbody fusion  Minimally invasive  Spondylolisthesis  Indirect decompression

English Abstract:

  【Abstract】 Objectives: To investigate the clinical outcomes and radiographic evaluation of bilateral pedicle screw instrumented (XLIF)extreme lateral interbody fusion for the treatment of lumbar spondylolisthesis. Methods: Clinical data of patients with lumbar spondylolisthesis treated with bilateral pedicle screw instrumented XLIF in Guangzhou General Hospital of Guangzhou Military Command from September 2014 to August 2016 were analyzed retrospectively. The study cohort consisted of 18 females and 3 males with an average age of 57.0±13.3(45-77) years. The mean follow-up was 18.0±5.0(12-29) months. Clinical outcomes were evaluated by using ODI(Oswestry disability index) and VAS(visual analogue scale) scores before surgery and at final follow-up. Anterior-posterior diameter of canal was assessed by MRI before surgery and 3 days after surgery. Foraminal height, disc height and slipping percentage were evaluated with plain lateral radiographs before surgery and at final follow-up. Fusion rate and cage subsidence were assessed on CT scans at final follow-up. Results: VAS scores for back pain before surgery and at final follow-up were 5.9±1.7 and 1.7±0.7 respectively. VAS scores for leg pain before surgery and at final follow-up were 6.1±2.1 and 1.4±0.7 respectively. ODI scores before surgery and at final follow-up were (42.6±24.8)% and (12.1±4.2)% respectively. VAS and ODI scores showed statistically significant improvements(P<0.05). Disc height was 7.2±1.2mm before surgery and 10.2±1.4mm at final follow-up. Foraminal height was 17.3±2.9mm before surgery and 20.0±1.7mm at final follow-up. Anterior-posterior diameter of canal was 11.2±3.8mm before surgery and 12.7±4.0mm at final follow-up. Slipping percentage was (16.4±7.0)% before surgery, and (6.1±6.6)% at final follow-up. These radiographic parameters showed statistically significant improvements(P<0.05). No severe complications associated with great vessel, abdominal visceras or genitofemoral nerve were observed. 5 patients presented with transient anterior thigh numbness, and the symptoms were resolved within 3 months. 2 patients showed cage subsidence, without obvious discomfort. Solid fusion was observed in all patients, and no fixation failure was found. Conclusions: The bilateral pedicle screw instrumented XLIF for the treatment of lumbar spondylolisthesis results in effective restoration of spondylolisthesis vertebra and an increase of the spinal canal at the operated levels via indirect decompression. XLIF is a treatment option available for lumbar spondylolisthesis, which is safe and efficienct.