Objective:

To investigate the early and middle stage efficacy and complications of minimally invasive extraperitoneal oblique lumbar interbody fusion (OLIF) in the treatment of degenerative lumbar diseases.

Methods:

The clinical data of 22 patients with degenerative lumbar diseases underwent OLIF from October 2017 to March 2019 were retrospectively analyzed, including 14 males and 8 females, aged from 51 to 72 years with an average of (63.15±7.22) years. There were 6 cases of lumbar spinal stenosis, 5 cases of lumbar spondylolisthesis, 4 cases of adjacent vertebral disease, 3 cases of degenerative lumbar scoliosis, 3 cases of discogenic low back pain, and 1 case of recurrence after posterior lumbar decompression. Posterior minimally invasive pedicle screw fixation was performed in 13 cases and Stand-alone fixation in 9 cases. Intraoperative blood loss, operation time, postoperative drainage volume, landing time were recorded. The intervertebral disc height(IDH), intervertebral foramen height(IFH), intervertebral foramen area( IFA), canal diameter(CD), canal area(CA) were measured before and after operation. The imaging changes (including location of fusion cage, interbody fusion, and cage subsidence) and complications were observed. Oswestry Disability Index (ODI), numerical rating scales (NRS) and Japanese Orthopaedic Association (JOA) scores were compared before and 3, 6, 12 months after operation.

Results:

All 22 patients successfully completed the operation. The intraoperative blood loss was 25 to 280 ml with an average of (95.45±79.07) ml and that of simple anterior approach was 25 to 70 ml with an average of (45.71±15.42) ml. The operation time was 75 to 210 min with an average of (137.72±37.66) min, and the simple anterior operation time was 75 to 105 min with an average of (91.40±15.96) min. The total drainage volume was 10 to 110 ml with an average of (56.23±31.15) ml, and the time to go down to the ground was 24 to 72 hours (54.48±18.24) hours after operation. Postoperative IDH improved (6.63±2.61)mm(P<0.05), the IFH improved (5.35±2.47)mm (P<0.05), the IFA improved (97.67±33.58)mm²(P<0.05), the CD improved (3.31±1.61) mm(P<0.05), the CA improved (57.52±31.39) mm²(P<0.05). Five patients got interbody fusion at 6 months after operation and all 22 patients got interbody fusion at 12 months after operation. There was 5 cases of fusion cage subsidence, all of which occurred in the cases without posterior fixation(using Stand-alone fixation). There was no serious complication such as big blood vessel injury, ureter injury, dural sac injury and nerve root injury. Peritoneal injury occurred in 1 case, postoperative transient thigh pain, decrease of quadriceps femoris muscle strength in 4 cases and sympathetic nerve injury in 1 case. The symptoms of lumbago and radicular pain of lower extremities were alleviated obviously 3 days after operation. The ODI, NRS and JOA scores at 6, 12 months after operation were significantly improved(P<0.05).

Conclusion:

The treatment of lumbar degenerative diseases with definite indications by OLIF can achieve satisfactory clinical results, and it has advantages of less intraoperative bleeding, fast time to land, less complications, good imaging improvement and indirect decompression. But the operation time and fluoroscopy time are longer in the early stage, and complications such as peritoneal injury and lumbar plexus over traction may occur. The long-term incidence of settlement of fusion cage with Stand-alone technology is higher.