Mid-term efficacy of midline lumbar interbody fusion in the treatment of lumbar degenerative diseases

English Keywords:Lumbar degenerative disease  Midline lumbar interbody fusion  Cortical bone trajectory  Outcomes  Indications

English Abstract:

  【Abstract】 Objectives: To compare and analyze the medium outcomes of midline lumbar interbody fusion(MIDLIF) with cortical bone trajectory(CBT) screw and posterior lumbar interbody fusion(PLIF) with pedicle screw(PS) in treating patients with lumbar degenerative diseases. Methods: 93 patients with lumbar degenerative diseases who underwent posterior lumbar decompression fusion surgery between February 2017 and April 2018 and finished time-point follow-up were reviewed. There were 45 cases in CBT group and 48 cases in PS group. The clinical outcomes were evaluated by visual analogue scale(VAS), Oswestry disability index(ODI), and Japanese Orthopaedic Association(JOA) Scores at 1 month after surgery and final follow-up. Antero-posterior and lateral X-rays and CT scans were performed to estimate the interbody fusion conditions, and the disc height, foraminal height, foraminal area and segmental lordosis of operated segments were measured before operation and at final follow-up. The modified MacNab scale was used for evaluating the ultimate outcomes, and the patient satisfaction was assessed through subjective feelings. Results: CBT group and PS group were followed up for 52.56±4.52 months and 52.08±3.92 months respectively. There were no statistically significant differences in age, sex, surgical level, preoperative VAS score of low back pain and leg pain, the ODI and JOA score between the two groups(P>0.05). The disc height, foraminal height, foraminal area and segmental lordosis of operated segement before surgery of the two groups were not significantly different from each other(P>0.05). Compared with pre-operation, the postoperative 1 month and final follow-up VAS scores of low back and leg pain, ODI, and JOA scores of both groups were statistically different(P<0.05); the postoperative 1 month and final follow-up disc height, foraminal height, foraminal area, and segmental lordosis of operated segments all increased(P<0.05); there was no statistical difference in corresponding indicators at postoperative 1 month and final follow-up between the two groups(P>0.05). All patients achieved bony fusion. 9 cases out of 93 occurred complications, including: 3 cases(6.7%) in CBT group, with 1 case of screw loosening and fusion cage dislocation, 1 case of isthmus fracture of the inferior pedicle, and 1 case of adjacent segement degeneration, none underwent re-operation; 6 cases in PS group, with 1 case of wound infection, 2 cases of screw loosening, 3 cases of adjacent segement degeneration, and 1 case of symptomatic ASD underwent re-operation. The overall complication rates between groups were not statistically different(P>0.05). The excellent-good rate of MacNab was 82.22%, and the satisfaction rate was 95.6% in CBT group at final follow-up; the excellent-good rate and satisfaction rate were 79.17% and 93.8% in PS group, and no statistically different between two groups(P>0.05). Conclusions: Comparing with PLIF with PS, MIDLIF can obtain consistently clinical outcomes in the treatment of lumbar degenerative diseases, with satisfactory medium results.