Abstract：
BACKGROUND: Degenerative spondylolisthesis causes translational and angular malalignment, resulting in a loss of segmental lordosis. This leads to compensatory adjustments in adjacent levels to maintain balance. Lateral lumbar interbody fusion (LLIF) and transforaminal lumbar interbody fusion (TLIF) are common techniques at L4-5. This study compares compensatory changes at adjacent L3-4 and L5-S1 levels six months post LLIF versus TLIF for grade 1 degenerative spondylolisthesis at L4-5.
METHODS: A retrospective study included patients undergoing L4-5 LLIF or TLIF with posterior pedicle screw instrumentation (no posterior osteotomy) for grade 1 spondylolisthesis. Pre-op and 6-month post-op radiographs measured segmental lordosis (L3-L4, L4-L5, L5-S1), lumbar lordosis (LL), and pelvic incidence (PI), along with PI-LL mismatch. Multiple regressions were used for hypothesis testing.
RESULTS: 113 patients (61 LLIF, 52 TLIF) were studied. TLIF showed less change in L4-5 lordosis (mean = 1.04°, SD = 4.34) compared to LLIF (mean = 4.99°, SD = 5.53) (p = 0.003). L4-5 angle changes didn\'t correlate with L3-4 changes, and no disparity between LLIF and TLIF was found (all p > 0.16). In LLIF, greater L4-5 lordosis change predicted reduced compensatory L5-S1 lordosis (p = 0.04), while no significant relationship was observed in TLIF patients (p = 0.12).
CONCLUSIONS: LLIF at L4-5 increases lordosis at the operated level, with compensatory decrease at L5-S1 but not L3-4. This reciprocal loss at adjacent L5-S1 may explain inconsistent improvement in lumbar lordosis (PI-LL) post L4-5 fusion.
METHODS: A retrospective study included patients undergoing L4-5 LLIF or TLIF with posterior pedicle screw instrumentation (no posterior osteotomy) for grade 1 spondylolisthesis. Pre-op and 6-month post-op radiographs measured segmental lordosis (L3-L4, L4-L5, L5-S1), lumbar lordosis (LL), and pelvic incidence (PI), along with PI-LL mismatch. Multiple regressions were used for hypothesis testing.
RESULTS: 113 patients (61 LLIF, 52 TLIF) were studied. TLIF showed less change in L4-5 lordosis (mean = 1.04°, SD = 4.34) compared to LLIF (mean = 4.99°, SD = 5.53) (p = 0.003). L4-5 angle changes didn\'t correlate with L3-4 changes, and no disparity between LLIF and TLIF was found (all p > 0.16). In LLIF, greater L4-5 lordosis change predicted reduced compensatory L5-S1 lordosis (p = 0.04), while no significant relationship was observed in TLIF patients (p = 0.12).
CONCLUSIONS: LLIF at L4-5 increases lordosis at the operated level, with compensatory decrease at L5-S1 but not L3-4. This reciprocal loss at adjacent L5-S1 may explain inconsistent improvement in lumbar lordosis (PI-LL) post L4-5 fusion.
摘要：
背景：退行性腰椎滑脱导致平移和角度错位，导致节段前凸丧失。这导致相邻级别的补偿性调整以保持平衡。外侧腰椎椎间融合术（LLIF）和经椎间孔腰椎椎间融合术（TLIF）是L4-5的常见技术。这项研究比较了LLIF和TLIF后六个月相邻L3-4和L5-S1水平在L4-5的1级退行性腰椎滑脱的代偿变化。
方法：一项回顾性研究包括接受L4-5LLIF或TLIF并使用后路椎弓根螺钉（无后路截骨术）治疗1级腰椎滑脱的患者。术前和术后6个月X线片测量节段前凸(L3-L4,L4-L5,L5-S1),腰椎前凸(LL),和骨盆发病率（PI），随着PI-LL不匹配。多元回归用于假设检验。
结果：113例患者（61例LLIF，52TLIF)进行了研究。TLIF显示L4-5脊柱前凸的变化较小（平均值=1.04°，SD=4.34)与LLIF(平均值=4.99°，SD=5.53)(p=0.003)。L4-5角度变化与L3-4变化不相关，LLIF和TLIF之间没有差异(所有p>0.16)。在LLIF中，L4-5脊柱前凸变化较大，可预测代偿性L5-S1脊柱前凸降低（p=0.04），而在TLIF患者中没有观察到显著的相关性(p=0.12)。
结论：L4-5的LLIF在手术水平上增加脊柱前凸，在L5-S1而不是L3-4代偿性降低。相邻L5-S1处的这种相互损失可能解释了L4-5融合后腰椎前凸（PI-LL）的不一致改善。
方法：一项回顾性研究包括接受L4-5LLIF或TLIF并使用后路椎弓根螺钉（无后路截骨术）治疗1级腰椎滑脱的患者。术前和术后6个月X线片测量节段前凸(L3-L4,L4-L5,L5-S1),腰椎前凸(LL),和骨盆发病率（PI），随着PI-LL不匹配。多元回归用于假设检验。
结果：113例患者（61例LLIF，52TLIF)进行了研究。TLIF显示L4-5脊柱前凸的变化较小（平均值=1.04°，SD=4.34)与LLIF(平均值=4.99°，SD=5.53)(p=0.003)。L4-5角度变化与L3-4变化不相关，LLIF和TLIF之间没有差异(所有p>0.16)。在LLIF中，L4-5脊柱前凸变化较大，可预测代偿性L5-S1脊柱前凸降低（p=0.04），而在TLIF患者中没有观察到显著的相关性(p=0.12)。
结论：L4-5的LLIF在手术水平上增加脊柱前凸，在L5-S1而不是L3-4代偿性降低。相邻L5-S1处的这种相互损失可能解释了L4-5融合后腰椎前凸（PI-LL）的不一致改善。
