MODIFIED-SENSORY ORGANIZATION TEST (mSOT)
Description
mSOT Report
Functional Implications
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Description
The mSOT protocol provides information about the interaction of the three sensory systems that contribute to postural control: somatosensory, visual and vestibular. During the assessment, inaccurate information is delivered to the patient's feet and joints through controlled, calibrated "sway referencing" of the support surface, which tilts to directly follow the patient's anteroposterior body sway. The mSOT does not provide information on visual-vestibular conflict resolution.
The mSOT measures how well a patient can maintain their postural stability under four sensory conditions:
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mSOT Comprehensive Report
- Equilibrium Score quantifies the Center of Gravity (COG) sway or postural stability under each of the three trials of the four sensory conditions. Effective use of sensory inputs is determined from the overall pattern of scores on the four conditions. The composite equilibrium score, the weighted average of the scores of all sensory conditions, characterizes the overall level of performance and is useful in documenting progress over time.
- Sensory Analysis ratios are used in conjunction with the individual equilibrium scores to determine the contribution of individual sensory systems. The mSOT does not include assessments of the visual system.
- Strategy Analysis quantifies the relative amount of movement about the ankles (ankle strategy) and about the hips (hip strategy) the patient used to maintain balance during each trial. Normal, stable individuals move primarily about the ankle joints when stable and shift to hip movements as they become less stable.
- Cog Alignment reflects the patient's COG position relative to the center of the base of support at the start of each trial of the SOT. Normal individuals maintain their COG near the center of the support base.
- The shaded area on each graphic represents performance outside of the normative data range. Green bars indicate performance within the normal range; red bars indicate performance outside the normal range.
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Functional Implications
Accurate organization of sensory information is critical to maintaining balance within the variety of environments encountered in daily life. An inability to organize sensory information appropriately can result in instability in environments where visual cues are diminished (darkness, lack of contrast/depth cues), or the surface is unstable or compliant (sandy beach, gravel driveway, boat deck, etc.). Inability to appropriately organize sensory information can lead to or be exacerbated by impairments in COG alignment and/or selection of movement strategies.
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