[Effects of oblique lateral interbody fusion and transforaminal lumbar interbody fusion for lordosis correction in degenerative lumbar diseases]

Objective: To compare the operation time, estimated blood loss, clinical outcome and correction of lumbar lordosis between oblique lateral interbody fusion (OLIF) and transforaminal lumbar interbody fusion (TLIF) in patients with degenerative lumbar diseases. Methods: Seventy-three patients who underwent OLIF or TLIF surgery from January 2016 to December 2017 in Sir Run Run Shaw Hospital Zhejiang University were analyzed in this retrospective case-control study. The patients included 31 males and 42 females, with a mean age of 65.8 years (range, 36-88 years). Of the patients, there were 9 cases of calcified disc herniation, 34 cases of spinal stenosis, 17 cases of degenerative spondylolithesis, 12 cases of degenerative scoliosis and 1 case of isthmic spondylolithesis. According to the type of surgery, patients were divided into OLIF group (34 cases) and TLIF group (39 cases). The operation time, estimated blood loss and transfusion were recorded, pre-and post-operative visual analogue scale (VAS) for back pain and Oswestry Disability Index (ODI) were evaluated, and pre- and post-operative lumbar lordosis (LL) and fused segment lordosis (FSL) were measured. Student t test were used in comparison between groups. Results: Ten (29.4%) patients in OLIF group and all 39 (100%) patients in TLIF group were supplemented with posterior instrumentation (χ(2)=41.013, P<0.05). The average operation time and estimated blood loss was significantly lower in OLIF group than in those in TLIF group[(163±68) vs (233±79) min, (116±148) vs (434±201) ml, t=4.019, 6.964, both P<0.05]. There was no significant differences in decreases value in VAS and ODI after surgery between the two groups (t=1.716, 0.522, both P>0.05). The correction of LL was 4.0°±10.0° in the OLIF group and 4.2°±6.1° in the TLIF group; the correction of FSL was 4.1°±7.0° in the OLIF group and 5.2°±4.6° in the TLIF group, with no significant differences between the two groups too (t=0.139, 0.805, both P>0.05). The correction of LL was significantly higher in OLIF group with posterior instrumentation than that in TLIF group (9.9°±11.1° vs 4.2°±6.1°, t=2.180, P<0.05). Conclusions: Both OLIF and TLIF can restore LL to some extent, but OLIF has obvious advantages in the operation time and blood loss during surgery. When supplemented with posterior instrumentation, OLIF can achieve better correction of LL than TLIF.