Oral Presentation Sydney Spinal Symposium 2018

Identifying who to treat:  Classification and agreement of sagittal balance and lumbopelvic compensation in the adult spine. (#9)

Larry Cohen 1 , Milena Simic 1 , Sarah Dennis 1 , Kathryn Refshauge 1 , Evangelos Pappas 1
  1. Faculty of Health Sciences, Sydney University, Sydney, NSW, Australia

Background

Spinal sagittal alignment (SSA) is associated with increased pain and reduced quality of life, especially in older people1. Early identification of compensatory responses to sagittal malalignment may allow more effective non-operative intervention.  Various methods to classify SSA and lumbopelvic compensations  are available.  

Aims

To evaluate adult SSA and lumbopelvic compensations, using two SSA classification methods.

Methods

A cross-sectional study of 107 adults (mean age 53±19 yr: 52% female), attending physiotherapy treatment,  who underwent  full-spine posterior-anterior and lateral EOS scans stratified above and below 57 years. We measured coronal and sagittal spinopelvic parameters to classify deformity, lordotic and sagittal lumbopelvic-compensatory classification, using SRS-Schwab1 and GAP2 methods.

We evaluated group and subgroup proportions of SSA, lordotic and pelvic compensatory classification with Fisher’s exact test and agreement between methods with Kappa statistics.

Results

Anterior imbalance and inclination was more prevalent in older adults identified by SRS-Schwab (64% vs 10%, P<0.001) and GAP analysis (75% vs 29%, P<0.001, Kappa=0.56) respectively. Significantly more older adults exhibited pelvic retroversion according to SRS-Schwab (62% vs 19%, P <0.001) and GAP (47% vs 19%, p=0.003, Kappa=0.62). Significantly more older adults exhibited lumbar hypolordosis according to SRS-Schwab (53% vs 21%, P<0.001), GAP (49%vs 19%, p<0.001) models (Kappa=0.62). Hyperlordosis was more prevalent in the younger group evaluated by SRS-Schwab (44% vs 11%, p<0.0001) and GAP (12% vs 2%,p=0.006).  The prevalence of compensated balanced and uncompensated imbalanced classification was 22% and 13% with SRS-Schwab and 4% and 14% when assessed by GAP analysis (Kappa=0.03).  The proportional agreement was highest with balanced (27%), decompensated imbalanced (18%) and least with uncompensated imbalanced (5%) and compensated balanced (4%) SSA classifications.

Conclusions

This study confirms more prevalent anterior sagittal balance, pelvic retroversion and lumbar hypolordosis in older adults and lumbar hyperlordosis in younger adults. The poor agreement in identifying compensated balance and uncompensated imbalance between two commonly used methods is concerning as these populations might be most in need3 and amenable to intervention.    

 

  1. 1. Smith JS, Klineberg E, Schwab F, Shaffrey CI, Moal B, Ames CP, Hostin R, Fu KM, Burton D, Akbarnia B, Gupta M, Hart R, Bess S, Lafage V, International Spine Study G (2013) 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 38 (19):16631671.
  2. 2. Yilgor , Sogunmez N, Boissiere L, Yavuz Y, Obeid I, Kleinstück F, Pérez-Grueso FJS, Acaroglu E, Haddad S, Mannion AF, Pellise F, Alanay A; European Spine Study Group (ESSG). Global Alignment and Proportion (GAP) Score: Development and Validation of a New Method of Analyzing Spinopelvic Alignment to Predict Mechanical Complications After Adult Spinal Deformity Surgery. J Bone Joint Surg Am. 2017 Oct 4;99(19):1661-1672. doi: 10.2106/JBJS.16.01594.
  3. 3. Lafage V1, Schwab F, Patel A, Hawkinson N, Farcy JP. Pelvic tilt and truncal inclination: two key radiographic parameters in the setting of adults with spinal deformity. Spine (Phila Pa 1976). 2009 Aug 1;34(17):E599-606. doi: 10.1097/BRS.0b013e3181aad219.