Are the sagittal cervical radiographic modifiers of the Ames-ISSG classification specific to adult cervical deformity?

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OBJECTIVE

The Ames–International Spine Study Group (ISSG) classification has recently been proposed as a tool for adult cervical deformity evaluation. This classification includes three radiographic cervical sagittal modifiers that have not been evaluated in asymptomatic adults. The aim of this study was to determine whether the sagittal radiographic modifiers described in the Ames-ISSG cervical classification are encountered in asymptomatic adults without alteration of health-related quality of life (HRQOL).

METHODS

The authors conducted a cross-sectional study of subjects with an age ≥ 18 years and no cervical or back-related complaints or history of orthopedic surgery. All subjects underwent full-body biplanar radiographs with the measurement of cervical, segmental, and global alignment and completed the SF-36 HRQOL questionnaire. Subjects were classified according to the sagittal radiographic modifiers (chin-brow vertical angle [CBVA], mismatch between T1 slope and cervical lordosis [TS-CL], and C2–7 sagittal vertical axis [cSVA]) of the Ames–ISSG classification for cervical deformity, which also includes a qualitative descriptor of cervical deformity, the modified Japanese Orthopaedic Association (mJOA) myelopathy score, and the Scoliosis Research Society (SRS)–Schwab classification for spinal deformity assessment. Characteristics of the subjects classified by the different modifier grades were compared.

RESULTS

One hundred forty-one asymptomatic subjects (ages 18–59 years, 71 females) were enrolled in the study. Twenty-seven (19.1%) and 61 (43.3%) subjects were classified as grade 1 in terms of the TS-CL and CBVA modifiers, respectively. Ninety-eight (69.5%) and 4 (2.8%) were grade 2 for these same respective modifiers. One hundred thirty-six (96.5%) subjects had at least one modifier at grade 1 or 2. There was a significant relationship between patient age and grades of TS-CL (p < 0.001, Cramer’s V [CV] = 0.32) and CBVA (p = 0.04, CV = 0.22) modifiers. The HRQOL, global alignment, and segmental alignment parameters were similar among the subjects with different modifier grades (p > 0.05).

CONCLUSIONS

The CBVA and TS-CL radiographic modifiers of the Ames-ISSG classification do not seem to be specific to subjects with cervical deformities and can occur in asymptomatic subjects without alteration in HRQOL.

ABBREVIATIONS ASD = adult spinal deformity; BMI = body mass index; CBVA = chin-brow vertical angle; CL = cervical lordosis; cSVA = C2–7 SVA; HRQOL = health-related quality of life; ISSG = International Spine Study Group; mJOA = modified Japanese Orthopaedic Association; PI-LL = pelvic incidence–lumbar lordosis; SRS = Scoliosis Research Society; SVA = sagittal vertical axis; TS-CL = mismatch between T1 slope and cervical lordosis.

Article Information

Correspondence Ayman Assi: University of Saint-Joseph, Beirut, Lebanon. ayman.assi@gmail.com; ayman.assi@usj.edu.lb.

INCLUDE WHEN CITING Published online July 27, 2018; DOI: 10.3171/2018.2.SPINE171285.

Disclosures This study was supported by the research council of the University of Saint-Joseph (grant no. FM189). The funding institution did not interfere in the study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the article for publication.

© AANS, except where prohibited by US copyright law.

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Figures

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    Representation of the parameters of sagittal cervical (A), segmental (B), and global alignment (C). CBVA = chin-brow vertical angle; CL = cervical lordosis angle; cSVA = C2–7 sagittal vertical axis; C7/S1 SVA = C7–S1 SVA; L1/L5 = L1–5 lordosis; PI = pelvic incidence; PT = pelvic tilt; SS = sacral slope; TS = T1 slope; T1/T12 = T1–12 kyphosis. Figure is available in color online only.

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    Distribution by age groups for the TS-CL (A), CBVA (B), and cSVA (C) modifiers of the Ames-ISSG classification. CV = Cramer’s V. Figure is available in color online only.

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    Global sagittal alignment parameters of subjects divided by the TS-CL modifier (upper) and CBVA modifier (lower) of the Ames-ISSG. Figure is available in color online only.

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    Distribution of SRS-Schwab sagittal modifier grades by the Ames-ISSG grades for CBVA modifier (upper) and TS-CL modifier (lower). Figure is available in color online only.

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    The HRQOL for subjects divided by the TS-CL (upper) and CBVA (lower) modifiers of the Ames-ISSG classification. Figure is available in color online only.

References

  • 1

    Akbar MTerran JAmes CPLafage VSchwab F: Use of Surgimap Spine in sagittal plane analysis, osteotomy planning, and correction calculation. Neurosurg Clin N Am 24:1631722013

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 2

    Ames CPSmith JSEastlack RBlaskiewicz DJShaffrey CISchwab F: Reliability assessment of a novel cervical spine deformity classification system. J Neurosurg Spine 23:6736832015

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 3

    Horton WCBrown CWBridwell KHGlassman SDSuk SICha CW: Is there an optimal patient stance for obtaining a lateral 36” radiograph? A critical comparison of three techniques. Spine (Phila Pa 1976) 30:4274332005

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 4

    Janssen MMDrevelle XHumbert LSkalli WCastelein RM: Differences in male and female spino-pelvic alignment in asymptomatic young adults: a three-dimensional analysis using upright low-dose digital biplanar X-rays. Spine (Phila Pa 1976) 34:E826E8322009

    • Search Google Scholar
    • Export Citation
  • 5

    Lafage RFerrero EHenry JKChallier VDiebo BLiabaud B: Validation of a new computer-assisted tool to measure spino-pelvic parameters. Spine J 15:249325022015

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 6

    Lafage RSchwab FChallier VHenry JKGum JSmith J: Defining spino-pelvic alignment thresholds: should operative goals in adult spinal deformity surgery account for age? Spine (Phila Pa 1976) 41:62682016

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 7

    Lee SHKim KTSeo EMSuk KSKwack YHSon ES: The influence of thoracic inlet alignment on the craniocervical sagittal balance in asymptomatic adults. J Spinal Disord Tech 25:E41E472012

    • Search Google Scholar
    • Export Citation
  • 8

    Moal BLafage VSmith JSAmes CPMundis GTerran JS: Clinical improvement through surgery for adult spinal deformity: what can be expected and who is likely to benefit most? Spine Deform 3:5665742015

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 9

    Sabbah IDrouby NSabbah SRetel-Rude NMercier M: Quality of life in rural and urban populations in Lebanon using SF-36 health survey. Health Qual Life Outcomes 1:302003

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 10

    Scheer JKTang JASmith JSAcosta FL JrProtopsaltis TSBlondel B: Cervical spine alignment, sagittal deformity, and clinical implications: a review. J Neurosurg Spine 19:1411592013

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 11

    Schwab FUngar BBlondel BBuchowski JCoe JDeinlein D: Scoliosis Research Society-Schwab adult spinal deformity classification: a validation study. Spine (Phila Pa 1976) 37:107710822012

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 12

    Smith JSKlineberg ESchwab FShaffrey CIMoal BAmes CP: 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) 38:166316712013

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 13

    Smith JSShaffrey CIFu KMGScheer JKBess SLafage V: Clinical and radiographic evaluation of the adult spinal deformity patient. Neurosurg Clin N Am 24:1431562013

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation

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