General Session: Adult Spinal Deformity
Presented by: R. Lafage - View Audio/Video Presentation (Members Only)
R. Lafage(1), I. Obeid(2), B. Liabaud(1), S. Bess(3), B. Line(4), D. Burton(5), J. Smith(6), C. Jalai(3), R. Hostin(7), C. Shaffrey(6), C. Ames(8), H.J. Kim(1), E. Klineberg(9), F. Schwab(1), V. Lafage(1), International Spine Study Group (ISSG)
(1) Hospital for Special Surgery, Spine Service, New York, NY, United States
(2) Centre Hospitalier, Universitaire de Bordeaux, Bordeaux, France
(3) NYU Langone Medical Center, Spine Division, Department of Orthopaedics, New York, NY, United States
(4) Rocky Mountain Hospital for Children Denver, Denver, CO, United States
(5) University of Kansas Medical Center, Department of Orthopaedic Surgery, Kansas City, KS, United States
(6) University of Virginia Medical Center, Department of Neurosurgery, Charlottesville, VA, United States
(7) Baylor Scoliosis Center, Plano, TX, United States
(8) San Francisco Medical Center, University of California, Department of Neurosurgery, San Francisco, NY, United States
(9) University of California, Davis, Department of Orthopedic Surgery, Sacramento, CA, United States
Introduction and Purpose: Surgical correction of adult spinal deformity (ASD) often includes the modification of lumbar lordosis (LL) to restore ideal sagittal alignment. However, corrections that include large changes in LL pose an increased risk for developing PJK. Little is known about the impact of cranial vs caudal (i.e. upper lumbar vs lower lumbar segments) correction in the lumbar spine on the occurrence of PJK. The purpose of this study was to investigate the impact of the location of lumbar correction on the development of PJK.
Methods: This study is a retrospective review of prospective, multicenter database. Surgically treated ASD patients with early follow-up (6 wks) and fusion of the full lumbo-sacral spine were included. Radiographic parameters included classic spino-pelvic parameters (PI, PT, PI-LL, and SVA) and the segmental correction spanning two adjacent intervertebral discs (Positive change meant a lordotic change). Using Glattes criteria, patients were stratified into PJK and noPJK, and propensity matched by age and regional lumbar correction (ΔPI-LL). Radiographic parameters and the segmental corrections were compared between PJK and noPJK patients using independent t-tests.
Results: 348 out of 483 patients were included in the analysis after propensity matching (64yo, 76% F, 50% with PJK). There were no significant differences between PJK and noPJK patients in baseline, post-op, or the change in alignment, with the exception of post-operative thoracic kyphosis [TK] and ΔTK (due to the influence of PJK). PJK pts had a decrease in segmental lordosis at L4-L5-S1 (-0.4 vs. 1.6°, p=0.027), and larger increase in segmental correction at cranial levels L1-L2-L3 (9.6 vs. 7.4°), T12-L1-L2 (7.3 vs. 5.3°), and T11-T12-L1 (2.8 vs. 0.6°), all p< 0.05.
Conclusions: Though the achievement of optimal sagittal alignment is the goal of realignment surgery, dramatic lumbar corrections appear to increase the risk of PJK. This study was the first to demonstrate that patients who developed PJK underwent kyphotic changes in the L4-S1 segments, as well as a restoration of lumbar lordosis at the more cranial levels (T12-L3). These findings suggest that restoring lordosis at the lower lumbar levels may lower the risk of PJK. Further studies may expand upon this work by investigating rod contouring in the uppermost fused segments.