To compare the clinical outcomes of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and open TLIF in treating recurrent degenerative lumbar diseases.

Fifty-two patients with single-segment degenerative lumbar disorders were divided into two groups. Twenty-four (17 males, 7 females with average age of 51.1 years) underwent MIS-TLIF surgery. Thirteen cases had the surgery at L_{4, 5} and eleven at L₅S₁. The primary surgeries were discectomy in 6 cases, discectomy with laminoplasty in 4 cases, laminectomy in 5 patients, and laminectomy and decompression in 9 cases. The reasons of revision surgeries were recurrent of lumber disc herniation in 10 cases and recurrent of lumbar spinal canal stenosis in 14 cases. Twenty-eight patients (20 males, 8 females with the mean age of 50.8 years) underwent open TLIF. Among them, one was at L_{2, 3}, 2 at L_{3, 4}, 17 at L_{4, 5} and 8 at L₅S₁ level. The reasons of revision surgeries were misdiagnosis in 1 case (no symptom relief after surgery), recurrent of lumber disc herniation in 23 cases and recurrent of lumbar spinal canal stenosis in 4 case. The primary surgeries were discectomy in 18 cases, microendoscopic discectomy (MED) in 2 cases, discectomy with laminoplasty in 4 cases, and laminectomy and decompression in 4 cases. The Japanese Orthopaedic Association (JOA) score, the visual analogue scale (VAS) of low back pain and leg pain were assessed during the postoperative follow-up. The lumbar interbody fusion rate and accuracy of pedicle screws were evaluated by CT scanning.

The mean operative duration was not significantly different (P>0.05) between two groups. The mean incision length, the average amount of blood loss, incision VAS at 1 and 3 days after the surgery were better in MIS-TLIF group than that in open TLIF group (P<0.05). The seconds of intraoperative X-ray fluoroscopy were 80±9 in MIS-TLIF group and 10±2 in open TLIF group (P<0.05). No neurological deficit was observed in both groups. Two cases had dura tear, two occurred surgical site infection in open TLIF group. There was no significant difference in the accuracy rates of pedicle screws between MIS-TLIF group (93.8%) and open TLIF group (88.4%). There was significantly different in the safe rates of pedicle screws between MIS-TLIF group (99.0%) and open TLIF group (94.7%). The mean follow-up duration was 27.8 months in MIS-TLIF group and 28.6 months in open TLIF group. The JOA scores and VAS of low back pain were significantly improved at the latest follow-up in both groups (P<0.05). No difference was observed between two groups in JOA scores, leg pain VAS and lumbar interbody fusion rate during follow-up. However, leg pain in MIS-TLIF group was better than that in open TLIF group. No implant-related complication was observed in both groups.

MIS-TLIF can effectively decrease the surgical trauma and rate of complications, improve the safety of pedicle screws implantation, and reduce surgical-related low back pain.

Lumbar vertebrae; Intervertebral disc degeneration; Spinal fusion; Recurrence; Surgical procedures, minimally invasive