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Fast treadmill walking combined with functional electrical stimulation to ankle muscles (FastFES) is a well-studied gait intervention that improves post-stroke walking function. Although individualized verbal feedback is commonly incorporated during clinical gait training, and a variable practice structure is posited to enhance learning, the influence of these two factors on motor learning during locomotor interventions such as FastFES is poorly understood. To determine if the addition of individualized verbal feedback or variable practice to a FastFES training session enhances motor learning of targeted gait patterns. Nine individuals with post-stroke hemiparesis completed a crossover study comprising exposure to 3 dose-matched types of gait training: (1) FastFES (FF), comprising five 6-minute bouts of training with intermittent FES, (2) FF with addition of individualized verbal instructions and faded feedback delivered by a physical therapist (FF+PT), (3) FF with variable gait speed and FES timing (FF+Var). Gait biomechanics data were collected before (Pre), immediately after (Post), and 24-h following (Retention) each training type. Within-session and retention change scores of 3 targeted gait variables were calculated to assess locomotor learning. FF+PT resulted in larger improvements within-session and at retention in trailing limb angle, and a trend for larger improvements in paretic pushoff compared to FF. FF+Var failed to show greater learning of biomechanical variables compared to FF. Addition of individualized verbal feedback (FF+PT) to a single session of gait training may enhance within- and across-session learning of targeted gait variables in people post-stroke, and merits more investigation. [ABSTRACT FROM AUTHOR]

The search for sensitive outcome measures that discriminate among subtypes of multiple sclerosis (MS) is important for targeting appropriate treatment and assessing the efficacy of intervention. Even more elusive are measures that can identify and track disease progression. Longitudinal studies targeted at assessing functional and neuromotor measures over time may enable us to characterize the natural history of the transition from non-progressive to progressive forms. In this multiple case study, we examined functional and neuromotor measures from three individuals who were part of a large-scale longitudinal study (N=93), and for whom we captured the transition to progressive MS. All participants were tested at 3 timepoints (approximately every 12 months) across 5 domains: patient-reported (Fatigue Severity Score, Visual Analog Fatigue Scale, Activities Balance Confidence Scale, Godin Leisure Time Questionnaire), mobility function (Timed 25 Foot Walk, Timed Up and Go), sensation (vibration sensitivity thresholds of foot and hand), proprioception (ankle- and elbow- position matching, and a multi-joint finger matching task) and motor (rapid foot and hand tapping). Only descriptive data will be reported. One participant transitioned between the first and second visits, while two transitioned between the second and third. Across most outcome measures there was rarely a linear change identified. Particularly for the participants for which transition occurred between visits 2 and 3, the second visit (just prior to their diagnosis of progressive MS) often demonstrated an inflection point of either worsening or improvement of neuromotor measures followed by a reversal towards their baseline levels. Foot vibration sensitivity demonstrated worsening that appeared to mirror means of the larger cohort, although there was a ceiling effect. These data underscore the need for robust longitudinal studies with frequent assessments to characterize how neuromotor and functional measures change prior to, during and following the transition from non-progressive to progressive MS. [ABSTRACT FROM AUTHOR]

• Foot-tapping and plantar cutaneous sensitivity but not ankle proprioception differed between MS subtypes. • Ambulation is associated with sensorimotor function in relapsing-remitting MS. • No association between ambulation and sensorimotor function in progressive MS. Disease progression of multiple sclerosis (MS) is often monitored by ambulatory measures, but how non-ambulatory sensorimotor measures differentially associate to walking measures in MS subtypes is unknown. We determined whether there are characteristic differences between relapsing-remitting MS (RRMS), progressive MS (PMS), and non-MS controls in lower extremity sensorimotor function and clinical walking tasks and the sensorimotor associations with walking function in each group. 18 RRMS, 13 PMS and 28 non-MS control participants were evaluated in their plantar cutaneous sensitivity (vibration perception threshold, Volts), proprioception during ankle joint position-matching (|∆°| in dorsiflexion), motor coordination (rapid foot-tap count/10 s), and walking function with three tests: Timed 25-foot walk (T25FW) at preferred and fast speeds (s), and timed-up-and-go (TUG, s). Foot-tapping (p = 0.039, Mean difference (MD)= 5.65 taps) and plantar cutaneous sensation (p = 0.026, MD= -10.30 V) differed between the MS subtypes. For the RRMS group faster walking was related to better proprioceptive function (preferred T25FW: p = 0.019, Root mean square error (RMSE)=1.94; fast T25FW: p = 0.004, RMSE=1.65; TUG: p = 0.001, RMSE=2.12) and foot-tap performance (preferred T25FW: p = 0.033, RMSE = 2.74; fast T25FW: p = 0.010, RMSE=2.02). These associations were not observed in the PMS group. Foot-tap performance and plantar cutaneous sensitivity but not ankle proprioception differed between MS subtypes. Lower walking performance was associated with lower foot-tapping and plantar cutaneous sensitivity in the RRMS but not the PMS group. This result suggests a change in the relationship of lower extremity sensorimotor function to walking performance in the PMS subtype. [ABSTRACT FROM AUTHOR]

• Both foot- and hand-tapping ability are lower in MS compared to controls. • Foot- but not hand-tapping ability differs between MS subtypes. • Antigravity movements during foot-tapping are impacted to a greater degree in MS. • Foot-tapping but not hand-tapping variability was higher in MS than controls. Rapid tapping tests have been shown to be reliable measures of upper motor neuron disease, and effectively examine motor function differences between multiple sclerosis (MS) and non-MS controls (CON), and between relapsing-remitting and progressive MS subtypes. To successfully perform rapid repetitive movements such as tapping, a person must be able to consistently turn on and off motor units to switch between the up and down movement phases. However, it is not clear which specific movement phase that occurs during tapping is different between MS subtypes. The objective of this study was to quantify and characterize performance differences during rapid hand- and foot-tapping tests between relapsing-remitting (RRMS) and progressive (PMS) forms of MS, as well as how both subtypes differ from non-MS controls. Participants in this study included 30 non-MS controls, 32 RRMS, and 31 PMS. Participants wore inertial sensors on all hands and feet and were instructed to tap as fast as possible for 10 s. Angular velocity from the gyroscope was used to quantify inter-tap interval (ms), coefficient of variation of inter-tap interval (COV), and up- and down-movement characteristics (duration (ms), COV, peak angular velocity (rad/s)). Differences between groups were examined with ANOVA and independent t-tests. Inter-tap interval was examined for its ability to distinguish between RRMS and PMS by a binary logistic regression analysis. Up-down movement characteristics were further evaluated for within-group directional differences (up- vs. down-phase movement components) with paired-sample t-tests. Inter-tap interval for both hand- and foot-tapping differed between controls and MS, but only foot tapping was different between RRMS and PMS (RRMS = 286.7 ± 83.0 ms; PMS = 379.5 ± 170.9 ms; mean difference (d) = -92.8 ms). Logistic regression analysis showed foot-tap interval but not hand-tap interval has the potential to distinguish between RRMS and PMS (Area under the ROC = 0.71). Both up- and down-movement duration differences were consistent with the results for inter-tap interval, but up-movement duration showed larger mean group differences than down-movement differences. No significant group differences in overall inter-tap interval COV were detected for either hand- or foot-tapping; however, up-movement foot-tapping variation (CON = 18.7 ± 6.1; RRMS = 25.5 ± 11.2; PMS = 23.3 ± 8.6; CON vs RRMS d = -6.8; CON vs PMS d = -4.7), but not down-movement variation was different between controls and MS. Up- and down-peak angular velocity during foot-tapping were different between controls and PMS (CON Up = 1.4 ± 0.5 rad/s; PMS Up = 1.0 ± 0.4 rad/s; Up d = 0.4 rad/s; CON Down= 1.5 ± 0.6 rad/s; PMS Down = 1.2 ± 0.5 rad/s; Down d = 0.3 rad/s), and up-movement peak angular velocity differences showed larger mean group differences than the down-movement peak angular velocity between controls and PMS. Foot-tapping differs between MS disease subtypes and has greater potential than hand-tapping to distinguish between subtypes. Performance in the up-movement showed larger group differences than the down-movement, suggesting that the anti-gravity up-movement during tapping may be more important diagnostically. Future studies should be conducted on the nature of the physiological mechanisms underlying impairments in anti-gravity movements in people with MS. [ABSTRACT FROM AUTHOR]