M. Ghedira

Postural stability in young healthy subjects – Impact of reduced base of support, visual deprivation, dual tasking

OBJECTIVEnTo provide normative postural stability data in young subjects.nnnMETHODSnNinety-six healthy participants (58W, 28±6y) stood on a force plate during 60s. We measured effects of support width (feet apart, FA; feet together, FT), vision (eyes open, EO; closed, EC), and cognitive load (single task, ST; dual tasking, DT) on anteroposterior (AP) and medio-lateral (ML) ranges, area and planar velocity of center of pressure (COP) trajectory.nnnRESULTSnAll variables increased with FT (AP range, +15%; ML, +185%; area, +242%; velocity, +50%, p<0.0002 for all, MANOVA). Visual deprivation increased COP ranges with added constraints (FT or DT, p=0.002) and increased velocity in all conditions (FA/ST, +16%; DT, +18%; FT/ST, +29%; DT, +23%, p<0.0002 for all). Dual tasking reduced COP displacements with FT (AP range, EO, -15%; EC, -11%; ML range, EO, -19%; EC, -13%; area, EO, -40%; EC, -28%, p<0.0002 for all) and increased velocity in most conditions (FA/EO, +15%; FA/EC, +16%; FT/EO, +7%, p<0.0002 for all).nnnCONCLUSIONnIn young healthy adults, base of support reduction increases COP displacements. Vision particularly affects postural stability with feet together or dual tasking. Dual tasking increases velocity but decreases COP displacements in challenging postural tasks, potentially by enhanced lower limb stiffness.

Intra- and inter-rater reliability of the 10-meter ambulation test in hemiparesis is better barefoot at maximal speed

Abstract Objectives Reliability of clinical tests to evaluate ambulation in chronic hemiparesis may vary according to the testing condition. The 10-meter ambulation test (AT10) assesses walking speed and step length over 10 m, starting and ending in seated position. In the present study, we compared the intra- and inter-reliability of AT10 in chronic hemiparesis in four different conditions: with shoes and barefoot, at free and maximal safe speed. Methods Ten patients with hemiparesis, >1 year post-stroke (age 45 ± 12, time since stroke 16 ± 9 months, mean ± SD) participated in the reliability study (registration, ID-RCB-2017-A00090-53). All patients performed the AT10 twice, one week apart, in each of the four conditions. The number of steps and time to complete the task were manually recorded by four independent raters. The main outcome measurements were the intraclass correlation coefficients (ICC), coefficients of variation (CV), and mean raw differences (DIFF) of the three parameters of AT10 (speed, step length, and cadence) in each of the four conditions. Effects of wearing shoes and speed condition were explored using ANOVA. Results Across all conditions, mean intra- and inter-rater ICCs were, respectively, 98.5 ± 0.1 and 99.9 ± 0.1% for speed, 98.3 ± 0.1 and 99.7 ± 0.2% for step length, and 96.5 ± 0.1 and 98.9 ± 0.6% for cadence. Mean intra- and inter-rater CV for speed were 0.051 ± 0.016 and 0.022 ± 0.002, respectively. Intra-rater reliability of speed assessments was higher at maximal than at free speed (ICC, CV, DIFF, p < 0.05). At free speed, intra-rater ICCs were higher barefoot than with shoes (p < 0.05). Discussion Performing the 10-meter ambulation test barefoot at maximal speed optimizes its reliability.

Effect of functional electrical stimulation of the peroneal nerve on antagonist resistances measured during swing phase of gait in spastic paresis. A randomized, controlled study

Introduction/Background In hemiparesis, functional electrical stimulation (FES) of the peroneal nerve aims to compensate for ankle dorsiflexor paresis in swing phase. The present prospective study compared the effects of gait training with FES vs. conventional therapy on plantar flexor overactivity. Material and method Twenty subjects with chronic hemiparesis (6xa0±xa04years post-lesion; meanxa0±xa0SD) were randomized into two groups: FES (45xa0min/day of gait self-training using FES) and Control (CON, 3xa0×xa045xa0min/week of conventional physiotherapy) for 10 weeks. Outcomes at Day 1 and Week 10 included comfortable speed barefoot gait analysis with gastrocnemius medialis (GM) and soleus (SO) electromyography, yielding:, walking speed; and, at the paretic ankle: maximal passive dorsiflexion during stance, maximal active dorsiflexion during swing, velocity of active dorsiflexion over early swing, coefficient of spastic cocontraction in GM and SO over the three thirds of swing (CSC, calculated by the ratio of the RMS of the electromyogram in the period of interest over the RMS of the electromyogram of the same muscle over 100xa0ms around its maximal voluntary contraction). Intra- and inter-group comparison used rank-ANOVAs. Results No difference was observed in walking speed changes (both groups pooled; D1, 0.73xa0±xa00.25xa0m/s, W10, 0.80xa0±xa00.30xa0m/s, ns) and in passive and active dorsiflexion amplitudes (ns). However, the velocity of active dorsiflexion increased in FES while it decreased in Controls (D1 vs. W10, FES, +5xa0±xa02°/s, Pxa0=xa00.02; CON, −4xa0±xa01°/s, Pxa0=xa00.04). In parallel, CSCGM in early swing tended to improve in FES only (FES, −41xa0±xa023%, Pxa0=xa00.09; CON, −24xa0±xa089%, ns; between group difference ns). Conclusion In chronic hemiparesis, FES, which focuses on agonist dorsiflexor stimulation during gait improves active dorsiflexion velocity in swing and may also be associated with reduction of plantar flexor spastic cocontraction. Further studies are required to confirm these findings and evaluate whether reciprocal inhibition toward plantar flexors may be restored by FES.

Wireless, accelerometry-triggered functional electrical stimulation of the peroneal nerve in spastic paresis: A randomized, controlled pilot study

ABSTRACT In hemiparesis, Wireless, Accelerometry-Triggered Functional Electrical Stimulation (WAFES) of the common peroneal nerve may hold intrinsic rehabilitative properties. The present pilot study analyzes WAFES against conventional therapy. Twenty adults with chronic hemiparesis (time since lesion 7(6) years; median (interquartile range)) were randomized into 2 10-week rehabilitation programs: a 45-minute (min) daily walk using WAFES (n = 10) and conventional physical therapy (CPT), 3 × 45 min per week (n = 10). The outcomes were 3D sagittal speed measurements, step length, cadence, maximal amplitude and velocity of hip, knee, and ankle during gait at free and fast speed without WAFES and clinical assessments of plantar flexor angles of shortening, spasticity, and weakness, before (D1) and after the program (W10). Kinematic and spasticity improvements occurred in the WAFES group only: (i) ankle dorsiflexion velocity (D1 versus W10, free speed, WAFES, +4(5)°/sec, p = 0.002; CPT, −3(8)°/sec, p = 0.007; fast, WAFES, +8(6)°/sec, p = 0.03; CPT, −1(4)°/sec, NS); (ii) maximal passive ankle dorsiflexion (WAFES,+26(85)%; CPT,+0(27)%; group-visit, p = 0.007) and knee flexion (WAFES, +13(17)%; CPT, −1(11)%; group-visit, p = 0.006) at fast speed only; (iii) 15% plantar flexor spasticity grade reduction with WAFES. Over 10 weeks, gait training using WAFES improved ankle and knee kinematics and reduced plantar flexor spasticity compared with CPT. Studies with longer WAFES use should explore functional effects.