Changes in Spino-pelvic Sagittal Parameters after Oblique Lateral Lumbar Interbody Fusion and Their Correlation with Clinical Outcome. Alternative therapies in health and medicine Objective:The study aimed to evaluate the impact of OLIF on spinal-pelvic sagittal parameters and its correlation with clinical outcomes in patients with degenerative lumbar spondylolisthesis. Methods:A retrospective analysis of 43 patients (23 males, 20 females) with lumbar 4/5 degenerative spondylolisthesis who underwent OLIF from January 2018 to January 2023 was conducted. Key parameters studied included SP, DH, FH, AS, LL, SS, PT, PI, and LASD. Results:All surgeries were successfully completed according to the original plan, and the minimum follow-up time was greater than 6 months, with a mean operation time of 198.21±51.32 min; the mean intraoperative bleeding volume was 121.00±56.88 ml. The VAS score of lumbar pain and ODI index decreased from the preoperative VAS score, and the ODI index of lower lumbar pain from the preoperative VAS score of 6.50±1.36 and 74.36±6.27 to the postoperative Lumbar pain of 3.20±1.28 and 32.41±8.21, respectively, and the differences were statistically significant (P < .05). 6.27 to 3.20±1.28 and 32.41±8.21 at the final follow-up visit. The differences were statistically significant (P < .05). The results of Pearson correlation analysis showed positive correlation between postoperative LL and FH, SP and AS, VAS (P < .05), and service correlation between SP and SS, LASD (P < .05), and correlation between pre- and post-surgery difference of LL, FH, SP and the improvement rate of ODI and VAS scores (P < .05), with the difference of pre- and post-surgery difference of LL, FH and the ODI, VAS score improvement rate were the strongest correlation. Postoperatively, significant improvements were observed in LL and FH. Pearson correlation analysis indicated a positive correlation between changes in sagittal parameters and clinical outcomes, measured by VAS and ODI scores. Conclusion:The postoperative spine-pelvis sagittal parameters were significantly improved compared with the preoperative ones, and the changes of the spine-pelvis sagittal parameters before and after the operation were correlated with the clinical outcomes, among which the differences of LL and FH had the strongest correlation with the improvement rates of ODI and VAS scores. OLIF effectively improved spinal-pelvic sagittal parameters and clinical outcomes in degenerative lumbar spondylolisthesis, with changes in LL and FH showing the strongest correlation with patient-reported outcome improvements. An oblique lateral interbody fusion can effectively reconstruct spine-pelvis sagittal parameters in patients with degenerative lumbar spondylolisthesis.

Distal Lumbar Lordosis is Associated With Reoperation for Adjacent Segment Disease After Lumbar Fusion for Degenerative Conditions. Global spine journal STUDY DESIGN:A single centre retrospective review. OBJECTIVE:Recent studies have suggested that distal lordosis (L4-S1, DL) remains constant across all pelvic incidence (PI) subgroups, whilst proximal lordosis (L1-L4, PL) varies. We sought to investigate the impact of post-operative DL on adjacent segment disease (ASD) requiring reoperation in patients undergoing lumbar fusion for degenerative conditions. METHODS:Patients undergoing 1-3 level lumbar fusion with the two senior authors between 2007-16 were included. Demographic and radiographic data were recorded. Univariate, multivariate binary logistic regression, and Kaplan Meier survivorship analyses were performed. RESULTS:335 patients were included in the final analysis. Most had single (67%) or two (31%) level fusions. The mean follow-up was 64-month. Fifty-seven patients (17%) underwent reoperation for ASD at an average of 78-month post-operatively (R group). The R group had a significantly lower mean post-operative DL (27.3 vs 31.1 deg, < .001) and mean PI (55.5 vs 59.2 deg, < .05). On univariate analysis, patients with a post-operative DL of <35 deg had higher odds of reoperation for ASD than those with a post-operative DL of ≥35 deg (OR 2.7, = .016). In the multivariate model, post-operative DL, low/average PI, and spondylolisthesis were all significantly associated with reoperation for ASD. CONCLUSION:This study provides preliminary support to an association between post-operative distal lumbar lordosis and risk of reoperation for ASD in patients undergoing fusions for degenerative conditions. Further multicentre prospective study is needed to independently confirm this association and identify the impact of restoration of physiological distal lumbar lordosis on long term patient outcomes. 10.1177/21925682241262704

The Effect of Changes in Segmental Lordosis on Global Lumbar and Adjacent Segment Lordosis After L5-S1 Anterior Lumbar Interbody Fusion. Global spine journal STUDY DESIGN:Retrospective Cohort Study. OBJECTIVE:Restoration of lordosis in lumbar fusion reduces low back pain, decreases adjacent segment degeneration, and improves postoperative outcomes. However, the potential effects of changes in segmental lordosis on adjacent-level and global lordosis remain less understood. This study aims to examine the relationships between segmental (SL), adjacent-level, and global lumbar lordosis following L5-S1 Anterior Lumbar Interbody Fusion (ALIF). METHODS:80 consecutive patients who underwent single-level L5-S1 ALIF were divided into 3 groups based on the degree of change (∆) in index-level segmental lordosis: <5° (n = 23), 5°-10° (n = 29), >10° (n = 28). Radiographic parameters measured included global lumbar, segmental, and adjacent level lordosis, sacral slope, pelvic tilt, pelvic incidence, and PI-LL mismatch. RESULTS:Patients with ∆SL 5°-10° or ∆SL >10° both showed significant increases in global lumbar lordosis from preoperative to final follow-up. However, patients with ∆SL >10° showed statistically significant losses in adjacent level lordosis at both immediate postoperative and final follow-up compared to preoperative. When comparing patients with ∆SL >10° to those with ∆SL 5-10°, there were no significant differences in global lumbar lordosis at final follow-up, due to significantly greater losses of adjacent level lordosis in these patients. CONCLUSION:The degree of compensatory loss of lordosis at the adjacent level L4-L5 correlated with the extent of segmental lordosis creation at the index L5-S1 level. This may suggest that the L4 to S1 segment acts as a "harmonious unit," able to accommodate only a certain amount of lordosis and further increases in segmental lordosis may be mitigated by loss of adjacent-level lordosis. 10.1177/21925682231195777

The change in lumbar lordosis from the standing to the lateral position: implications for lateral interbody fusion. European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society PURPOSE:The purpose of this cross-sectional, observational study was to establish the relationship between standing lumbar lordosis (LL) and lateral decubitus LL. METHODS:Forty-nine subjects, 24 male and 25 female, were prospectively enrolled. Patients with pre-existing spinopelvic pathology were excluded. Standing, relaxed-seated, and lateral decubitus lateral radiographs were obtained. Radiographic variables measured included LL and lordosis change at each lumbar level (e.g. L1-L2). The change in LL when going from a standing to a lateral decubitus position (ΔLL), the correlation between standing and sitting LL compared to lateral decubitus LL, and the correlation between ΔLL and standing pelvic incidence (PI), pelvic tilt (PT), PI-LL mismatch, pelvic femoral angle (PFA), and sacral slope (SS) were calculated. RESULTS:Subjects had an average age of 25.7 ± 2.3 years and body mass index of 24.1 ± 3.0 kg/m. On average, 11.9°±8.2° (range - 7° to 29°) of LL was lost when transitioning from a standing to the lateral decubitus position. Lateral decubitus LL had a higher correlation with standing LL (R = 0.725, p < 0.001) than with relaxed-seated LL (R = 0.434, p < 0.001). Standing PT and PI-LL mismatch had moderately negative correlations with ΔLL (R=-0.58 and R=-0.59, respectively, both p < 0.05). Standing PI and standing PFA had a low negative correlation with ΔLL (R=-0.31 and R=-0.44, respectively, both p < 0.05) Standing SS and LL had no correlation with ΔLL. CONCLUSIONS:Standing LL was strongly correlated to lateral decubitus LL, although subjects lost an average of 11.9° from the standing to the lateral decubitus position. This has important implications for fusion in the lateral position. 10.1007/s00586-024-08493-2