Assessment of stability during gait in patients with spinal deformity—A preliminary analysis using the dynamic stability margin

Anne Laure Simon, Vipul Lugade, Kathie Bernhardt, A. Noelle Larson, Kenton R Kaufman

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Daily living activities are dynamic, requiring spinal motion through space. Current assessment of spinal deformities is based on static measurements from full-spine standing radiographs. Tools to assess dynamic stability during gait might be useful to enhance the standard evaluation. The aim of this study was to evaluate gait dynamic imbalance in patients with spinal deformity using the dynamic stability margin (DSM). Twelve normal subjects and 17 patients with spinal deformity were prospectively recruited. A kinematic 3D gait analysis was performed for the control group (CG) and the spinal deformity group (SDG). The DSM (distance between the extrapolated center of mass and the base of support) and time-distance parameters were calculated for the right and left side during gait. The relationship between DSM and step length was assessed using three variables: gait stability, symmetry, and consistency. Variables’ accuracy was validated by a discriminant analysis. Patients with spinal deformity exhibited gait instability according to the DSM (0.25 m versus 0.31 m) with decreased velocity (1.1 m s−1 versus 1.3 m s−1) and decreased step length (0.32 m versus 0.38 m). According to the discriminant analysis, gait stability was the more accurate variable (area under the curve AUC = 0.98) followed by gait symmetry and consistency. However, gait consistency showed 100% of specificity, sensitivity, and accuracy of precision. The DSM showed that patients with spinal malalignment exhibit decreased gait stability, symmetry, and consistency besides gait time-distance parameter changes. Additional work is required to determine how to apply the DSM for preoperative and postoperative spinal deformity management.

Original languageEnglish (US)
Pages (from-to)37-42
Number of pages6
JournalGait and Posture
Volume55
DOIs
StatePublished - Jun 1 2017

Fingerprint

Gait
Discriminant Analysis
Area Under Curve
Activities of Daily Living
Biomechanical Phenomena
Spine
Sensitivity and Specificity
Control Groups

Keywords

  • Base of support
  • Dynamic stability margin
  • Extrapolated center of mass
  • Gait stability
  • Spinal deformity

ASJC Scopus subject areas

  • Biophysics
  • Orthopedics and Sports Medicine
  • Rehabilitation

Cite this

Assessment of stability during gait in patients with spinal deformity—A preliminary analysis using the dynamic stability margin. / Simon, Anne Laure; Lugade, Vipul; Bernhardt, Kathie; Larson, A. Noelle; Kaufman, Kenton R.

In: Gait and Posture, Vol. 55, 01.06.2017, p. 37-42.

Research output: Contribution to journalArticle

Simon, Anne Laure ; Lugade, Vipul ; Bernhardt, Kathie ; Larson, A. Noelle ; Kaufman, Kenton R. / Assessment of stability during gait in patients with spinal deformity—A preliminary analysis using the dynamic stability margin. In: Gait and Posture. 2017 ; Vol. 55. pp. 37-42.
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