The surgical correction of adult spinal deformity (ASD) often involves modifying lumbar lordosis (LL) to restore ideal sagittal alignment. However, corrections that include large changes in LL increase the risk for development of proximal junctional kyphosis (PJK). Little is known about the impact of cranial versus caudal correction in the lumbar spine on the occurrence of PJK. The goal of this study was to investigate the impact of the location of the correction on acute PJK development.
This study was a retrospective review of a prospective multicenter database. Surgically treated ASD patients with early follow-up evaluations (6 weeks) and fusions of the full lumbosacral spine were included. Radiographic parameters analyzed included the classic spinopelvic parameters (pelvic incidence [PI], pelvic tilt [PT], PI−LL, and sagittal vertical axis [SVA]) and segmental correction. Using Glattes’ criteria, patients were stratified into PJK and noPJK groups and propensity matched by age and regional lumbar correction (ΔPI−LL). Radiographic parameters and segmental correction were compared between PJK and noPJK patients using independent t-tests.
After propensity matching, 312 of 483 patients were included in the analysis (mean age 64 years, 76% women, 40% with PJK). There were no significant differences between PJK and noPJK patients at baseline or postoperatively, or between changes in alignment, with the exception of thoracic kyphosis (TK) and ΔTK. PJK patients had a decrease in segmental lordosis at L4-L5-S1 (−0.6° vs 1.6°, p = 0.025), and larger increases in segmental correction at cranial levels L1-L2-L3 (9.9° vs 7.1°), T12-L1-L2 (7.3° vs 5.4°), and T11-T12-L1 (2.9° vs 0.7°) (all p < 0.05).
Although achievement of an 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 while restoring LL at more cranial levels (T12–L3). These findings suggest that restoring lordosis at lower lumbar levels may result in a decreased risk of developing PJK.
Correspondence Virginie Lafage: Hospital for Special Surgery, New York, NY. firstname.lastname@example.org.
INCLUDE WHEN CITING Published online October 26, 2018; DOI: 10.3171/2018.6.SPINE161468.
Disclosures The International Spine Study Group (ISSG) is funded through research grants from DePuy Synthes (current), NuVasive (current), K2M (current), Innovasis (past), Biomet (past), and individual donations. Dr. Obeid reports being a consultant for DePuy Synthes and Medtronic; receiving clinical or research support for the study from DePuy Synthes; and receiving royalties from Alphatec Spine, Spineart, and Clariance. Dr. Bess reports being a consultant for K2 and Allosource; receiving clinical or research support for the study from Biomet, DePuy Spine, and Innovasis; being a patent holder for K2; and receiving support of non–study-related clinical or research effort from Medtronic, Stryker, and NuVasive. Dr. Burton reports receiving royalties and research support of non–study-related clinical or research effort from DePuy. Dr. Smith reports being a consultant for Zimmer Biomet, NuVasive, and Cerapedics; receiving royalties from Zimmer Biomet; receiving support of non–study-related clinical or research effort from DePuy Synthes/ISSG; receiving clinical or research support for the study from DePuy Synthes/ISSG; receiving fellowship support from NREF and AO Spine; and receiving an honorarium for teaching from K2M. Dr. Hostin reports being a consultant for DePuy; and receiving support of non–study-related clinical or research effort from NuVasive, Seeger, DJO, DePuy, and K2M. Dr. Shaffrey reports being a consultant for Medtronic, NuVasive, Zimmer-Biomet, K2M, and Stryker; direct stock ownership of NuVasive; and being a patent holder and receiving royalties from Medtronic, NuVasive, and Zimmer-Biomet. Dr. Ames reports being a consultant for DePuy, Medtronic, and Stryker; being a patent holder for Fish & Richardson, P.C.; and receiving royalties from Stryker and Biomet Spine. Dr. Klineberg reports direct stock ownership in Nemaris, Inc.; being a consultant for NuVasive; receiving speaking/teaching arrangements from DePuy Spine, K2M, and MSD; and receiving support of non–study-related clinical or research effort from DePuy Spine, Stryker, NuVasive, and K2M (paid through ISSGF). Dr. Schwab reports direct stock ownership in Nemaris, Inc.; support of non–study-related clinical or research effort from DePuy Spine, NuVasive, Stryker, and K2M; and being a consultant for and receiving speaking/teaching arrangements from Zimmer-Biomet, Medicrea, MSD, K2M, and NuVasive. Dr. V. Lafage reports direct stock ownership in Nemaris, Inc.; being a consultant for NuVasive; receiving support of non–study-related clinical or research effort from DePuy Spine, K2M, Stryker, and NuVasive (paid through ISSGF); and speaking/teaching arrangements from DePuy Spine, NuVasive, MSD, and K2M.
BiancoKNortonRSchwabFSmithJSKlinebergEObeidI: Complications and intercenter variability of three-column osteotomies for spinal deformity surgery: a retrospective review of 423 patients. Neurosurg Focus36(5):E182014
DieboBGLafageRAmesCPBessSObeidIKlinebergE: Ratio of lumbar 3-column osteotomy closure: patient-specific deformity characteristics and level of resection impact correction of truncal versus pelvic compensation. Eur Spine J25:2480–24872016
GlattesRCBridwellKHLenkeLGKimYJRinellaAEdwardsCII: Proximal junctional kyphosis in adult spinal deformity following long instrumented posterior spinal fusion: incidence, outcomes, and risk factor analysis. Spine (Phila Pa 1976)30:1643–16492005
HamiltonDKKanterASBolingerBDMundisGMJrNguyenSMummaneniPV: Reoperation rates in minimally invasive, hybrid and open surgical treatment for adult spinal deformity with minimum 2-year follow-up. Eur Spine J25:2605–26112016
HostinRMcCarthyIOʼBrienMBessSLineBBoachie-AdjeiO: Incidence, mode, and location of acute proximal junctional failures after surgical treatment of adult spinal deformity. Spine (Phila Pa 1976)38:1008–10152013
KimHJBridwellKHLenkeLGParkMSSongKSPiyaskulkaewC: Patients with proximal junctional kyphosis requiring revision surgery have higher postoperative lumbar lordosis and larger sagittal balance corrections. Spine (Phila Pa 1976)39:E576–E5802014
KimHJYagiMNyugenJCunninghamMEBoachie-AdjeiO: Combined anterior-posterior surgery is the most important risk factor for developing proximal junctional kyphosis in idiopathic scoliosis. Clin Orthop Relat Res470:1633–16392012
LafageRBessSGlassmanSAmesCBurtonDHartR: Virtual modeling of postoperative alignment after adult spinal deformity surgery helps predict associations between compensatory spinopelvic alignment changes, overcorrection, and proximal junctional kyphosis. Spine (Phila Pa 1976)42:E1119–E11252017
LoweTGKastenMD: An analysis of sagittal curves and balance after Cotrel-Dubousset instrumentation for kyphosis secondary to Scheuermann’s disease. A review of 32 patients. Spine (Phila Pa 1976)19:1680–16851994
MoalBSchwabFAmesCPSmithJSRyanDMummaneniPV: Radiographic outcomes of adult spinal deformity correction: a critical analysis of variability and failures across deformity patterns. Spine Deform2:219–2252014
ParkSJLeeCSChungSSLeeJYKangSSParkSH: Different risk factors of proximal junctional kyphosis and proximal junctional failure following long instrumented fusion to the sacrum for adult spinal deformity: survivorship analysis of 160 patients. Neurosurgery80:279–2862017
ProtopsaltisTSchwabFBronsardNSmithJSKlinebergEMundisG: The T1 pelvic angle, a novel radiographic measure of global sagittal deformity, accounts for both spinal inclination and pelvic tilt and correlates with health-related quality of life. J Bone Joint Surg Am96:1631–16402014
RoussoulyPGolloglySBerthonnaudEDimnetJ: Classification of the normal variation in the sagittal alignment of the human lumbar spine and pelvis in the standing position. Spine (Phila Pa 1976)30:346–3532005
SchwabFPatelAUngarBFarcyJPLafageV: Adult spinal deformity-postoperative standing imbalance: how much can you tolerate? An overview of key parameters in assessing alignment and planning corrective surgery. Spine (Phila Pa 1976)35:2224–22312010
SchwabFJDieboBGSmithJSHostinRShaffreyCICunninghamME: Fine-tuned surgical planning in adult spinal deformity: determining the lumbar lordosis necessary by accounting for both thoracic kyphosis and pelvic incidence. Spine J14 (11 Suppl):S732014(Abstract)
SmithJSKlinebergESchwabFShaffreyCIMoalBAmesCP: Change in classification grade by the SRS-Schwab Adult Spinal Deformity Classification predicts impact on health-related quality of life measures: prospective analysis of operative and nonoperative treatment. Spine (Phila Pa 1976)38:1663–16712013
YagiMKingABBoachie-AdjeiO: Incidence, risk factors, and natural course of proximal junctional kyphosis: surgical outcomes review of adult idiopathic scoliosis. Minimum 5 years of follow-up. Spine (Phila Pa 1976)37:1479–14892012