Defining Spino-Pelvic Alignment Thresholds: Should Operative Goals in Adult Spinal Deformity Surgery Account for Age?

STUDY DESIGN.Retrospective review of prospective, multicenter database. OBJECTIVE.The aim of the study was to determine age-specific spino-pelvic parameters, to extrapolate age-specific Oswestry Disability Index (ODI) values from published Short Form (SF)-36 Physical Component Score (PCS) data, and...

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Published in:Spine (Philadelphia, Pa. 1976) Pa. 1976), 2016-01, Vol.41 (1), p.62-68
Main Authors: Lafage, Renaud, Schwab, Frank, Challier, Vincent, Henry, Jensen K, Gum, Jeffrey, Smith, Justin, Hostin, Richard, Shaffrey, Christopher, Kim, Han J, Ames, Christopher, Scheer, Justin, Klineberg, Eric, Bess, Shay, Burton, Douglas, Lafage, Virginie
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Language:English
Subjects:
Adult
Age Factors
Aged
Female
Humans
Male
Middle Aged
Pelvis - physiopathology
Pelvis - surgery
Quality of Life
Retrospective Studies
Severity of Illness Index
Spinal Curvatures - epidemiology
Spinal Curvatures - physiopathology
Spinal Curvatures - surgery
Spine - physiopathology
Spine - surgery
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cited_by cdi_FETCH-LOGICAL-c3522-52c76c6f51f826fa09ec12e4388a3b77b986bd5c76b9ee79c72673cb40f8a03b3
cites cdi_FETCH-LOGICAL-c3522-52c76c6f51f826fa09ec12e4388a3b77b986bd5c76b9ee79c72673cb40f8a03b3
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container_issue 1
container_start_page 62
container_title Spine (Philadelphia, Pa. 1976)
container_volume 41
creator Lafage, Renaud
Schwab, Frank
Challier, Vincent
Henry, Jensen K
Gum, Jeffrey
Smith, Justin
Hostin, Richard
Shaffrey, Christopher
Kim, Han J
Ames, Christopher
Scheer, Justin
Klineberg, Eric
Bess, Shay
Burton, Douglas
Lafage, Virginie
description STUDY DESIGN.Retrospective review of prospective, multicenter database. OBJECTIVE.The aim of the study was to determine age-specific spino-pelvic parameters, to extrapolate age-specific Oswestry Disability Index (ODI) values from published Short Form (SF)-36 Physical Component Score (PCS) data, and to propose age-specific realignment thresholds for adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA.The Scoliosis Research Society-Schwab classification offers a framework for defining alignment in patients with ASD. Although age-specific changes in spinal alignment and patient-reported outcomes have been established in the literature, their relationship in the setting of ASD operative realignment has not been reported. METHODS.ASD patients who received operative or nonoperative treatment were consecutively enrolled. Patients were stratified by age, consistent with published US-normative values (Norms) of the SF-36 PCS (75  y old). At baseline, relationships between between radiographic spino-pelvic parameters (lumbar-pelvic mismatch [PI-LL], pelvic tilt [PT], sagittal vertical axis [SVA], and T1 pelvic angle [TPA]), age, and PCS were established using linear regression analysis; normative PCS values were then used to establish age-specific targets. Correlation analysis with ODI and PCS was used to determine age-specific ideal alignment. RESULTS.Baseline analysis included 773 patients (53.7 y old, 54% operative, 83% female). There was a strong correlation between ODI and PCS (r = 0.814, P  0.510, P 
doi_str_mv 10.1097/BRS.0000000000001171
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OBJECTIVE.The aim of the study was to determine age-specific spino-pelvic parameters, to extrapolate age-specific Oswestry Disability Index (ODI) values from published Short Form (SF)-36 Physical Component Score (PCS) data, and to propose age-specific realignment thresholds for adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA.The Scoliosis Research Society-Schwab classification offers a framework for defining alignment in patients with ASD. Although age-specific changes in spinal alignment and patient-reported outcomes have been established in the literature, their relationship in the setting of ASD operative realignment has not been reported. METHODS.ASD patients who received operative or nonoperative treatment were consecutively enrolled. Patients were stratified by age, consistent with published US-normative values (Norms) of the SF-36 PCS (&lt;35, 35–44, 45–54, 55–64, 65–74, &gt;75  y old). At baseline, relationships between between radiographic spino-pelvic parameters (lumbar-pelvic mismatch [PI-LL], pelvic tilt [PT], sagittal vertical axis [SVA], and T1 pelvic angle [TPA]), age, and PCS were established using linear regression analysis; normative PCS values were then used to establish age-specific targets. Correlation analysis with ODI and PCS was used to determine age-specific ideal alignment. RESULTS.Baseline analysis included 773 patients (53.7 y old, 54% operative, 83% female). There was a strong correlation between ODI and PCS (r = 0.814, P &lt; 0.001), allowing for the extrapolation of US-normative ODI by age group. Linear regression analysis (all with r &gt; 0.510, P &lt; 0.001) combined with US-normative PCS values demonstrated that ideal spino-pelvic values increased with age, ranging from PT = 10.9 degrees, PI−LL = −10.5 degrees, and SVA = 4.1 mm for patients under 35 years to PT = 28.5 degrees, PI−LL = 16.7 degrees, and SVA = 78.1 mm for patients over 75 years. Clinically, older patients had greater compensation, more degenerative loss of lordosis, and were more pitched forward. CONCLUSION.This study demonstrated that sagittal spino-pelvic alignment varies with age. Thus, operative realignment targets should account for age, with younger patients requiring more rigorous alignment objectives.Level of Evidence3</description><identifier>ISSN: 0362-2436</identifier><identifier>EISSN: 1528-1159</identifier><identifier>DOI: 10.1097/BRS.0000000000001171</identifier><identifier>PMID: 26689395</identifier><language>eng</language><publisher>United States: Copyright Wolters Kluwer Health, Inc. All rights reserved</publisher><subject>Adult ; Age Factors ; Aged ; Female ; Humans ; Male ; Middle Aged ; Pelvis - physiopathology ; Pelvis - surgery ; Quality of Life ; Retrospective Studies ; Severity of Illness Index ; Spinal Curvatures - epidemiology ; Spinal Curvatures - physiopathology ; Spinal Curvatures - surgery ; Spine - physiopathology ; Spine - surgery</subject><ispartof>Spine (Philadelphia, Pa. 1976), 2016-01, Vol.41 (1), p.62-68</ispartof><rights>Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c3522-52c76c6f51f826fa09ec12e4388a3b77b986bd5c76b9ee79c72673cb40f8a03b3</citedby><cites>FETCH-LOGICAL-c3522-52c76c6f51f826fa09ec12e4388a3b77b986bd5c76b9ee79c72673cb40f8a03b3</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><link.rule.ids>314,780,784,27924,27925</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/26689395$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Lafage, Renaud</creatorcontrib><creatorcontrib>Schwab, Frank</creatorcontrib><creatorcontrib>Challier, Vincent</creatorcontrib><creatorcontrib>Henry, Jensen K</creatorcontrib><creatorcontrib>Gum, Jeffrey</creatorcontrib><creatorcontrib>Smith, Justin</creatorcontrib><creatorcontrib>Hostin, Richard</creatorcontrib><creatorcontrib>Shaffrey, Christopher</creatorcontrib><creatorcontrib>Kim, Han J</creatorcontrib><creatorcontrib>Ames, Christopher</creatorcontrib><creatorcontrib>Scheer, Justin</creatorcontrib><creatorcontrib>Klineberg, Eric</creatorcontrib><creatorcontrib>Bess, Shay</creatorcontrib><creatorcontrib>Burton, Douglas</creatorcontrib><creatorcontrib>Lafage, Virginie</creatorcontrib><creatorcontrib>International Spine Study Group</creatorcontrib><title>Defining Spino-Pelvic Alignment Thresholds: Should Operative Goals in Adult Spinal Deformity Surgery Account for Age?</title><title>Spine (Philadelphia, Pa. 1976)</title><addtitle>Spine (Phila Pa 1976)</addtitle><description>STUDY DESIGN.Retrospective review of prospective, multicenter database. OBJECTIVE.The aim of the study was to determine age-specific spino-pelvic parameters, to extrapolate age-specific Oswestry Disability Index (ODI) values from published Short Form (SF)-36 Physical Component Score (PCS) data, and to propose age-specific realignment thresholds for adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA.The Scoliosis Research Society-Schwab classification offers a framework for defining alignment in patients with ASD. Although age-specific changes in spinal alignment and patient-reported outcomes have been established in the literature, their relationship in the setting of ASD operative realignment has not been reported. METHODS.ASD patients who received operative or nonoperative treatment were consecutively enrolled. Patients were stratified by age, consistent with published US-normative values (Norms) of the SF-36 PCS (&lt;35, 35–44, 45–54, 55–64, 65–74, &gt;75  y old). At baseline, relationships between between radiographic spino-pelvic parameters (lumbar-pelvic mismatch [PI-LL], pelvic tilt [PT], sagittal vertical axis [SVA], and T1 pelvic angle [TPA]), age, and PCS were established using linear regression analysis; normative PCS values were then used to establish age-specific targets. Correlation analysis with ODI and PCS was used to determine age-specific ideal alignment. RESULTS.Baseline analysis included 773 patients (53.7 y old, 54% operative, 83% female). There was a strong correlation between ODI and PCS (r = 0.814, P &lt; 0.001), allowing for the extrapolation of US-normative ODI by age group. Linear regression analysis (all with r &gt; 0.510, P &lt; 0.001) combined with US-normative PCS values demonstrated that ideal spino-pelvic values increased with age, ranging from PT = 10.9 degrees, PI−LL = −10.5 degrees, and SVA = 4.1 mm for patients under 35 years to PT = 28.5 degrees, PI−LL = 16.7 degrees, and SVA = 78.1 mm for patients over 75 years. Clinically, older patients had greater compensation, more degenerative loss of lordosis, and were more pitched forward. CONCLUSION.This study demonstrated that sagittal spino-pelvic alignment varies with age. 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OBJECTIVE.The aim of the study was to determine age-specific spino-pelvic parameters, to extrapolate age-specific Oswestry Disability Index (ODI) values from published Short Form (SF)-36 Physical Component Score (PCS) data, and to propose age-specific realignment thresholds for adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA.The Scoliosis Research Society-Schwab classification offers a framework for defining alignment in patients with ASD. Although age-specific changes in spinal alignment and patient-reported outcomes have been established in the literature, their relationship in the setting of ASD operative realignment has not been reported. METHODS.ASD patients who received operative or nonoperative treatment were consecutively enrolled. Patients were stratified by age, consistent with published US-normative values (Norms) of the SF-36 PCS (&lt;35, 35–44, 45–54, 55–64, 65–74, &gt;75  y old). At baseline, relationships between between radiographic spino-pelvic parameters (lumbar-pelvic mismatch [PI-LL], pelvic tilt [PT], sagittal vertical axis [SVA], and T1 pelvic angle [TPA]), age, and PCS were established using linear regression analysis; normative PCS values were then used to establish age-specific targets. Correlation analysis with ODI and PCS was used to determine age-specific ideal alignment. RESULTS.Baseline analysis included 773 patients (53.7 y old, 54% operative, 83% female). There was a strong correlation between ODI and PCS (r = 0.814, P &lt; 0.001), allowing for the extrapolation of US-normative ODI by age group. Linear regression analysis (all with r &gt; 0.510, P &lt; 0.001) combined with US-normative PCS values demonstrated that ideal spino-pelvic values increased with age, ranging from PT = 10.9 degrees, PI−LL = −10.5 degrees, and SVA = 4.1 mm for patients under 35 years to PT = 28.5 degrees, PI−LL = 16.7 degrees, and SVA = 78.1 mm for patients over 75 years. Clinically, older patients had greater compensation, more degenerative loss of lordosis, and were more pitched forward. CONCLUSION.This study demonstrated that sagittal spino-pelvic alignment varies with age. Thus, operative realignment targets should account for age, with younger patients requiring more rigorous alignment objectives.Level of Evidence3</abstract><cop>United States</cop><pub>Copyright Wolters Kluwer Health, Inc. All rights reserved</pub><pmid>26689395</pmid><doi>10.1097/BRS.0000000000001171</doi><tpages>7</tpages></addata></record>
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subjects Adult
Age Factors
Aged
Female
Humans
Male
Middle Aged
Pelvis - physiopathology
Pelvis - surgery
Quality of Life
Retrospective Studies
Severity of Illness Index
Spinal Curvatures - epidemiology
Spinal Curvatures - physiopathology
Spinal Curvatures - surgery
Spine - physiopathology
Spine - surgery
title Defining Spino-Pelvic Alignment Thresholds: Should Operative Goals in Adult Spinal Deformity Surgery Account for Age?
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