General Session: Thoraco-Lumbar Degenerative
Presented by: C. Hill - View Audio/Video Presentation (Members Only)
K. Kim(1), R. Denhaese(2), C. Hill(3), K.B. Strenge(3), A. de Moura(4), P. Passias(4), R. Panchal(1), P. Arnold(5), A. Kranenburg(6), M. Dennis(7), A. Cappuccino(8), T. Thaiyananthan(9), C. Ferry(10), B. Ventimiglia(10), T. Glorioso((1)(1)), S. Martineck((1)(2)), K. Martin(10)
(1) UC Davis, Sacramento, CA, United States
(2) AXIS Neurosurgery and Spine, Williamsville, NY, United States
(3) Orthopaedic Institute, Paducah, KY, United States
(4) New York Spine Institute, New York, NY, United States
(5) University of Kansas, Kansas City, KS, United States
(6) Southern Oregon Orthopedics, Medford, OR, United States
(7) South Texas Spinal Clinic, San Antonio, TX, United States
(8) Buffalo Spine Surgery, Buffalo, NY, United States
(9) Brain And Spine Institute of California, Newport Beach, CA, United States
(10) Zimmer Biomet Spine, Broomfield, CO, United States
((1) (1) ) University of Colorado - Denver, Denver, CO, United States
((1) (2) ) Clinical Trials Consultant, Buffalo, NY, United States
Introduction: Anterior (ALIF) and lateral (LLIF) interbody fusion techniques continue to receive much favor as effective interventions when treating pain secondary to segmental degeneration and/or instability. The ability to achieve good disc visualization with each respective approach allows for the placement of a large interbody graft and subsequent sagittal reduction and neural decompression. However, given the distinctly unique access approaches associated with each technique, it is valuable to understand whether differences may exist in complication profiles and patient outcomes. The objective of this study was to provide prospective evidence, out to 2-years, comparing circumferential LLIF and ALIF with either interspinous process fixation (ISPF) or pedicle screw fixation (PSF).
Materials and Methods: Data was collected as part of a prospective, controlled, multi-center (11 investigators) study with 24-months follow-up. A total of 103 subjects were enrolled. All subjects underwent single-level circumferential LLIF (n=57) or ALIF (n=46) for the treatment of degenerative disc disease and/or spondylolisthesis (≤ Grade 2). Interbody technique (ALIF or LLIF) was selected at the discretion of the surgeon in accordance with their institutional standard-of-care. Subjects were randomized to ISPF or PSF in the posterior aspect. Intraoperative, patient reported, complication/revision, and radiographic outcomes were reported. Statistical analysis was performed using a linear mixed model.
Results: Specific to the interbody approach, LLIF subjects required significantly less intraoperative blood loss, operative time, and incisions lengths; however, ALIF subjects required significantly less fluoroscopy.
All cohorts demonstrated significant ODI score improvement from baseline out to 24mos. At 24mos, mean ODI improvement stratified by interbody approach and posterior fixation was: ALIF+ISPF: 19.2; ALIF+PSF: 26.7; LLIF+ISPF: 26.0; LLIF+PSF: 19.8pts. The only significant difference in ODI improvement was observed at 6mos, with LLIF+ISPF subjects exceeding all other cohorts (p < 0.05). Collective ALIF and LLIF cohorts demonstrated ODI score improvements of 22.2 and 24.0, respectively, at 24mos. Trends in SF-36 (mental and physical) and ZCQ (physical, symptom, and satisfaction) were consistent with those observed for ODI. Postoperative complication profiles were comparable between groups and with the literature. No revision procedures were performed between 12 and 24mos due to interbody approach related complications (< 12mos revisions previously reported). 24mo. interbody fusion (BSF-3) rates were: ALIF+ISPF: 100%; LLIF+ISPF: 91.7%; ALIF+PSF: 80%; LLIF+PSF: 86.7%.
Conclusions: At 24mos, both ALIF and LLIF demonstrated clinically advantageous trends in patient reported outcomes, radiographic outcomes, and complication profiles. Type of posterior fixation did not appear to be differentiating amongst or across interbody cohorts with respect to 24mo. follow-up, however, LLIF and ISPF appeared most advantageous intraoperatively and early in the post-operative period (≤ 6mos).
Fig 1. ODI Improvement vs Time
Fig 2. LLIF+ISPF; 12mo Fusion (BSF-3