Epicritic Sensation in Cervical Spinal Cord Injury: Diagnostic Gains Beyond Testing Light Touch

Abstract

Applied as a bedside test of gross dorsal column function, the testing of light touch (LT) sensation is of high clinical value in the diagnosis of human spinal cord injury (SCI). However, the assessment of overall dorsal column deficit by testing only LT may be limited, because the dorsal column pathway conveys several large diameter afferent modalities (e.g., sensation of touch, two-point discrimination, and proprioception). Therefore, the objective of this study was to compare the epicritic sensation assessed by LT, Semmes-Weinstein monofilament (SWM), and electrical perception threshold (EPT) across cervical dermatomes (C3-C8) in individuals with cervical SCI. A multicenter cross-sectional study was performed at 6 months after cervical SCI, applying combined measures of LT, SWM, and EPT, bilaterally over predefined key sensory points (C3-C8). A total of 300 left-and right-sided dermatomes were tested for each outcome measure in 25 participants. The percentage agreement between classifications according to LT and SWM/EPT testing for all dermatomes between C3 and C8 ranged from 95.5% to 36.2%. The degree of agreement showed considerably variable coefficients (-0.1kw0.7) for each dermatome between C3 and C8. The additional measurements of epicritic sensation by SWM and EPT increased sensitivity by detecting and quantifying differences in sensory thresholds above, at, and below the LT level of injury. This is relevant for early clinical trials (phase 1/2), in which disclosing any biological activity of an intervention may be revealed by subtle sensory changes that might gain a clinical relevance. AbstractApplied as a bedside test of gross dorsal column function, the testing of light touch (LT) sensation is of high clinical value in the diagnosis of human spinal cord injury (SCI). However, the assessment of overall dorsal column deficit by testing only LT may be limited, because the dorsal column pathway conveys several large diameter afferent modalities (e.g., sensation of touch, two-point discrimination, and proprioception). Therefore, the objective of this study was to compare the epicritic sensation assessed by LT, Semmes-Weinstein monofilament (SWM), and electrical perception threshold (EPT) across cervical dermatomes (C3-C8) in individuals with cervical SCI. A multicenter cross-sectional study was performed at 6 months after cervical SCI, applying combined measures of LT, SWM, and EPT, bilaterally over predefined key sensory points (C3-C8). A total of 300 left-and right-sided dermatomes were tested for each outcome measure in 25 participants. The percentage agreement between classifications according to LT and SWM/EPT testing for all dermatomes between C3 and C8 ranged from 95.5% to 36.2%. The degree of agreement showed considerably variable j coefficients ( -0.1 ‡ k w £ 0.7) for each dermatome between C3 and C8. The additional measurements of epicritic sensation by SWM and EPT increased sensitivity by detecting and quantifying differences in sensory thresholds above, at, and below the LT...

Changes in Strength, Sensation, and Prehension in Acute Cervical Spinal Cord Injury

“…However, SWM was significant and more sensitive to small gains between 1 and 3 months, something not found with LT (C6-C8). The present results suggest that SWM is sensitive to minor impairments, which are less detectable by LT testing; findings also confirmed in cross-sectional studies by Kalsi-Ryan et al 13 and Velstra et al 34 These authors observed greater sensitivity of the SWM in individuals with acute and chronic SCI compared with the values reported when using LT.…”

Technical development of transcutaneous electrical nerve inhibition using medium-frequency alternating current

“…Measurements were made by pressing each monofilament to the skin. Measurements started with the smallest diameter monofilament (an ascending method of threshold testing) [ 19 ]. The monofilament was held in contact with the skin until it bent, and then removed after 1 s. Participants were asked to close their eyes and to indicate whether they could sense the monofilament stimulation [ 20 ].…”

Outcome of the upper limb in cervical spinal cord injury: Profiles of recovery and insights for clinical studies

“…AIS D patients could potentially be studied with interventions as well if the outcome measures used do not have ceiling effects for the AIS D subgroup. For studies including cervical AIS D patients, measures such as electrical perceptual thresholds, 21 and measures of manual dexterity 22 could be employed to avoid the challenges of a ceiling effect that are inherent in the more conventional measurement techniques used. The AIS CD group that converted was entirely made up of AIS C patients that converted to D. This group generally started at a lower point than the AIS D patients; showed significant recovery in the first 3 months and then followed a similar recovery profile as the AIS D group.…”