Relationship between postoperative lordosis distribution index and adjacent segment disease following L4-S1 posterior lumbar interbody fusion

• Published in: Journal of orthopaedic surgery and research 2020-04, Vol.15 (1), p.129-129, Article 129
• Main Authors: Zheng, Guoquan, Wang, Chunguo, Wang, Tianhao, Hu, Wenhao, Ji, Quanbo, Hu, Fanqi, Li, Jianrui, Chaudhary, Surendra K, Song, Kai, Song, Diyu, Zhang, Zhifa, Hao, Yongyu, Wang, Yao, Li, Jing, Zheng, Qingyuan, Zhang, Xuesong, Wang, Yan
• Format: Article
• Language: English
• Subjects: Adjacent segment disease; Age; Aged; Analysis; Arthritis; Back surgery; Biomechanics; Body mass index; Clinical outcomes; Comorbidity; Data collection; Degenerative disc disease; Disease susceptibility; Female; Follow-Up Studies; Fractures; Gender; Hospitals; Humans; Lordosis; Lordosis - diagnostic imaging; Lordosis - etiology; Lordosis distribution index; Lower lumbar lordosis; Lumbar lordosis; Lumbar Vertebrae - diagnostic imaging; Lumbar Vertebrae - surgery; Male; Middle Aged; Orthopedics; Patients; Posterior lumbar interbody fusion; Postoperative Complications - diagnostic imaging; Postoperative Complications - etiology; Postoperative period; Retrospective Studies; Sacrum - diagnostic imaging; Sacrum - surgery; Scoliosis; Spinal Diseases - diagnostic imaging; Spinal Diseases - surgery; Spinal Fusion - adverse effects; Spinal Fusion - trends; Spine (lumbar); Statistical analysis; Surgeons; Surgery; Survival
• ISSN: 1749-799X; 1749-799X
• DOI: 10.1186/s13018-020-01630-9

Adjacent segment disease (ASD) is an acknowledged problem of posterior lumbar interbody fusion (PLIF). Many studies have been reported concerning the role of lordosis distribution index (LDI) in spinal biomechanics. However, few reports have been published about the impact of LDI on ASD following L4-S1 PLIF. The study enrolled 200 subjects who underwent L4-S1 PLIF for degenerative spine disease from 2009 to 2014. The average follow-up term was 84 months. Several lower lumbar parameters were measured, including lower lumbar lordosis (LLL), lumbar lordosis (LL), pelvic incidence (PI), and LDI on the pre and postoperative radiograph. Perioperative information, comorbidities, and operative data were documented. Kaplan-Meier curves were plotted for the comparisons of ASD-free survival of 3 different types of postoperative LDI subgroups. The incidence of ASD was found to be 8.5%. LL and LLL increased by 3.96° (38.71° vs 42.67°; P < 0.001) and 3.60° (26.22° vs 28.82°; P < 0.001) after lower lumbar fusion surgery, respectively. Lordosis distribution index (LDI) increased by 0.03 (0.66 vs 0.69, P = 0.004) postoperatively. A significant difference (P = 0.001) was observed when comparing the incidence of ASD among postoperative LDI subgroups. The Kaplan-Meier curves showed a marked difference in ASD-free survival between low and moderate LDI subgroup (log-rank test, P = 0.0012) and high and moderate LDI subgroup (log-rank test, P = 0.0005). Patients with abnormal postoperative LDI were statistically more likely to develop ASD than those who had normal postoperative LDI. Moreover, patients with low postoperative LDI were at greater risk for developing ASD than those with high postoperative LDI over time.