Impact of cephalad versus caudal lumbar lordosis correction on spinal shape and outcomes of complex deformity spine surgery.
Academic Article
Overview
abstract
PURPOSE: To compare the impact of lumbar lordosis correction achieved by cephalad versus caudal distribution on radiographic alignment and surgical outcomes among adult spinal deformity (ASD) patients. METHODS: Patients who underwent ASD surgery with uppermost instrumented vertebrae (UIV) at or above L1, had preoperative pelvic incidence-lumbar lordosis (PI-LL) > 10°, and had full-body radiographs available were included. Eligible patients were categorized by the focus of lordosis correction: caudal (L4-S1 lordosis between 35 and 45°) and cephalad lordosis-based correction. Patient demographics, preoperative and 2 years spinopelvic alignment and PROMs, and 2 years postoperative surgical complications were compared. RESULTS: In total, 187 (111 caudal and 76 cephalad) patients were included, with mean age of 66.2 years, 78.6% female, and mean frailty score of 3.6. Caudally-restored patients often had an upper thoracic UIV, sacrum/ilium LIV, longer length of fusion, and no lateral lumbar interbody fusion (LLIF) while cephaladly-restored patients had two or more LLIFs above L4 (p < 0.001). Preoperatively, there were no significant differences in radiographic alignment and PROMs between the two groups (p > 0.02). Two years postoperatively, caudally-restored patients had higher L1-S1 LL (p = 0.015) and L4-S1 LL (p < 0.001), and lower PI-LL (p = 0.039) and SVA (p = 0.001). In addition, they had higher SRS-22 activity (p = 0.045), pain (p = 0.047), appearance (p = 0.046), and total (p = 0.016) scores. Finally, they had lower rates of sensory deficits (p < 0.001), motor deficits (p = 0.003), implant failure (p = 0.092), and reoperation (p = 0.020). CONCLUSION: Caudal lordosis-based correction of spinal deformity patients was associated with higher PROMs and lower rates of neurologic deficits, implant failure, and revisions at 2 years. These findings, while subject to unmeasured confounding, indicate that great caution should be taken when considering cephalad-based correction of ASD.
