TY - JOUR
T1 - Paraspinal muscle size as an independent risk factor for proximal junctional kyphosis in patients undergoing thoracolumbar fusion
AU - Pennington, Zach
AU - Cottrill, Ethan
AU - Ahmed, A. Karim
AU - Passias, Peter
AU - Protopsaltis, Themistocles
AU - Neuman, Brian
AU - Kebaish, Khaled M.
AU - Ehresman, Jeff
AU - Westbroek, Erick M.
AU - Goodwin, Matthew L.
AU - Sciubba, Daniel M.
N1 - Funding Information:
Dr. Passias: consultant for Medicrea and SpineWave; teaching and speaking honoraria from Zimmer Biomet; scientific advisory board for Allosource; funding from Medicrea, SpineWave, Allosource, Zimmer Biomet, Globus, Cervical Spine Research Society, and Aesculap; and clinical or research support for this study from Aesculap. Dr. Protopsaltis: consultant for Medicrea, NuVasive, Globus, K2M, and Innovasis; direct stock ownership in Torus Medical; and research support from Zimmer Spine and the Cervical Spine Research Society. Dr. Neuman: research grant from DePuy-Synthes for this study and lecture speaker for Medtronic. Dr. Kebaish: consultant for DePuy-Synthes and K2M, royalties from DePuy-Synthes and Orthofix, and honoraria from K2M. Dr. Goodwin: consultant for ROM3 Rehab and Augmedics, and royalties from Kendall Hunt Publishing. Dr. Sciubba: consultant for Baxter, DePuy-Synthes, Globus, K2M, Medtronic, NuVasive, Stryker.
Funding Information:
Dr. Passias: consultant for Medicrea and SpineWave; teaching and speaking honoraria from Zimmer Biomet; scientific advisory board for Allosource; funding from Medicrea, SpineWave, Allo-source, Zimmer Biomet, Globus, Cervical Spine Research Society, and Aesculap; and clinical or research support for this study from Aesculap. Dr. Protopsaltis: consultant for Medicrea, NuVasive, Globus, K2M, and Innovasis; direct stock ownership in Torus Medical; and research support from Zimmer Spine and the Cer- vical Spine Research Society. Dr. Neuman: research grant from DePuy-Synthes for this study and lecture speaker for Medtronic. Dr. Kebaish: consultant for DePuy-Synthes and K2M, royalties from DePuy-Synthes and Orthofix, and honoraria from K2M. Dr. Goodwin: consultant for ROM3 Rehab and Augmedics, and royalties from Kendall Hunt Publishing. Dr. Sciubba: consultant for Baxter, DePuy-Synthes, Globus, K2M, Medtronic, NuVasive, Stryker.
Publisher Copyright:
© 2019 AANS.
PY - 2019
Y1 - 2019
N2 - Objective: Proximal junctional kyphosis (PJK) is a structural complication of spinal fusion in 5%.61% of patients treated for adult spinal deformity. In nearly one-third of these cases, PJK is progressive and requires costly surgical revision. Previous studies have suggested that patient body habitus may predict risk for PJK. Here, the authors sought to investigate abdominal girth and paraspinal muscle size as risk factors for PJK. Methods: All patients undergoing thoracolumbosacral fusion greater than 2 levels at a single institution over a 5-year period with ≥ 6 months of radiographic follow-up were considered for inclusion. PJK was defined as kyphosis ≥ 20° between the upper instrumented vertebra (UIV) and two supra-adjacent vertebrae. Operative and radiographic parameters were recorded, including pre- and postoperative sagittal vertical axis (SVA), sacral slope (SS), lumbar lordosis (LL), pelvic tilt, pelvic incidence (PI), and absolute value of the pelvic incidence.lumbar lordosis mismatch (|PI-LL|), as well as changes in LL, |PI-LL|, and SVA. The authors also considered relative abdominal girth and the size of the paraspinal muscles at the UIV. Results: One hundred sixty-nine patients met inclusion criteria. On univariate analysis, PJK was associated with a larger preoperative SVA (p < 0.001) and |PI-LL| (p = 0.01), and smaller SS (p = 0.004) and LL (p = 0.001). PJK was also associated with more positive postoperative SVA (p = 0.01), ΔSVA (p = 0.01), Δ|PI-LL| (p < 0.001), and ΔLL (p < 0.001); longer construct length (p = 0.005); larger abdominal girth.to-muscle ratio (p = 0.007); and smaller paraspinal muscles at the UIV (p < 0.001). Higher postoperative SVA (OR 1.1 per cm), smaller paraspinal muscles at the UIV (OR 2.11), and more aggressive reduction in |PI-LL| (OR 1.03) were independent predictors of radiographic PJK on multivariate logistic regression. Conclusions: A more positive postoperative global sagittal alignment and smaller paraspinal musculature at the UIV most strongly predicted PJK following thoracolumbosacral fusion.
AB - Objective: Proximal junctional kyphosis (PJK) is a structural complication of spinal fusion in 5%.61% of patients treated for adult spinal deformity. In nearly one-third of these cases, PJK is progressive and requires costly surgical revision. Previous studies have suggested that patient body habitus may predict risk for PJK. Here, the authors sought to investigate abdominal girth and paraspinal muscle size as risk factors for PJK. Methods: All patients undergoing thoracolumbosacral fusion greater than 2 levels at a single institution over a 5-year period with ≥ 6 months of radiographic follow-up were considered for inclusion. PJK was defined as kyphosis ≥ 20° between the upper instrumented vertebra (UIV) and two supra-adjacent vertebrae. Operative and radiographic parameters were recorded, including pre- and postoperative sagittal vertical axis (SVA), sacral slope (SS), lumbar lordosis (LL), pelvic tilt, pelvic incidence (PI), and absolute value of the pelvic incidence.lumbar lordosis mismatch (|PI-LL|), as well as changes in LL, |PI-LL|, and SVA. The authors also considered relative abdominal girth and the size of the paraspinal muscles at the UIV. Results: One hundred sixty-nine patients met inclusion criteria. On univariate analysis, PJK was associated with a larger preoperative SVA (p < 0.001) and |PI-LL| (p = 0.01), and smaller SS (p = 0.004) and LL (p = 0.001). PJK was also associated with more positive postoperative SVA (p = 0.01), ΔSVA (p = 0.01), Δ|PI-LL| (p < 0.001), and ΔLL (p < 0.001); longer construct length (p = 0.005); larger abdominal girth.to-muscle ratio (p = 0.007); and smaller paraspinal muscles at the UIV (p < 0.001). Higher postoperative SVA (OR 1.1 per cm), smaller paraspinal muscles at the UIV (OR 2.11), and more aggressive reduction in |PI-LL| (OR 1.03) were independent predictors of radiographic PJK on multivariate logistic regression. Conclusions: A more positive postoperative global sagittal alignment and smaller paraspinal musculature at the UIV most strongly predicted PJK following thoracolumbosacral fusion.
KW - Adjacent-segment disease
KW - Adult spinal deformity
KW - Body morphometry
KW - Obesity
KW - Proximal junctional kyphosis
KW - Sagittal balance
UR - http://www.scopus.com/inward/record.url?scp=85072011640&partnerID=8YFLogxK
U2 - 10.3171/2019.3.SPINE19108
DO - 10.3171/2019.3.SPINE19108
M3 - Article
C2 - 31151107
AN - SCOPUS:85072011640
SN - 1547-5654
VL - 31
SP - 380
EP - 388
JO - Journal of Neurosurgery: Spine
JF - Journal of Neurosurgery: Spine
IS - 3
ER -