Ultrasonographic Measures of the Acromiohumeral Distance and Supraspinatus Tendon Thickness in Manual Wheelchair Users With Spinal Cord Injury.

OBJECTIVES: (1) To evaluate the reliability of ultrasonographic measures of the acromiohumeral distance (AHD) in shoulder positions linked to wheelchair propulsion in manual wheelchair users (MWUs) with spinal cord injury (SCI) and able-bodied individuals; (2) to compare ultrasonographic measures of AHD, supraspinatus tendon thickness, and occupation ratio between MWUs with SCI with and without shoulder pain (rotator cuff [RC] tendinopathy); and (3) to compare these ultrasonographic measures between MWUs with SCI and able-bodied individuals. DESIGN: Cross-sectional study. SETTING: Rehabilitation centers. PARTICIPANTS: Three groups of participants (N=95; aged between 18 and 60y) were recruited within a convenience sample: objective 1: 16 MWUs with SCI (mean age, 43±9y; height, 172±13 cm, weight, 84±10 kg) and 16 able-bodied individuals (mean age, 28±9y; height, 176±11 cm, weight, 72±12 kg); objectives 2 and 3: 37 MWUs with SCI (17 with [mean age, 47±11y; height, 172±14 cm, weight, 68±11 kg] and 20 without [mean age, 45±10y; height, 172±15 cm, weight, 84±30 kg] RC tendinopathy) and 26 able-bodied individuals (mean age, 31±5y; height, 175±12 cm; weight, 89±14 kg). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: AHD, supraspinatus tendon thickness, and occupation ratio of the supraspinatus tendon measured using ultrasound imaging systems. RESULTS: (1) Excellent intra- and interrater reliability of AHD was obtained in each arm position (intraclass correlation coefficient>.85); (2) MWUs without shoulder pain have thicker tendon than do MWUs with RC tendinopathy; and (3) a significant Group × Position interaction was found for AHD measures when comparing MWUs with SCI with able-bodied individuals (greater AHD at the end of the push phase for MWUs with SCI). A thicker tendon and a higher occupation ratio were also found in MWUs with SCI than in able-bodied individuals. CONCLUSIONS: Ultrasonography is a reliable technology to evaluate AHD in MWUs in shoulder positions linked to wheelchair propulsion. Supraspinatus tendon thickness and occupation ratio of AHD adequately discriminate between MWUs with SCI and able-bodied individuals. This shows that these ultrasonographic measures can be used in future studies of populations with SCI to better understand the changes at the shoulder joint in MWUs.

Development and reliability of a measure evaluating dynamic proprioception during walking with a robotized ankle-foot orthosis, and its relation to dynamic postural control.

BACKGROUND: Proprioception is important for proper motor control. As the central nervous system modulates how sensory information is processed during movement (sensory gating), proprioceptive tests performed at rest do not correlate well with performance during dynamic tasks such as walking. Proprioception therefore needs to be assessed during movement execution. OBJECTIVES: 1) To develop a test evaluating the ability to detect movement errors during walking, and its test-retest reliability; 2) to quantify the relationship between proprioceptive threshold (obtained with this new test) and performance in a standardized dynamic balance task. METHOD: Thirty healthy subjects walked on a treadmill while wearing a robotized ankle-foot orthosis (rAFO) for 2 bouts of 6min on 2 evaluation sessions (test-retest reliability). Force perturbations resisting ankle dorsiflexion during swing were applied to the ankle via the rAFO (150ms duration, variable amplitude). Participants pushed a button when they detected the perturbations. The Star Excursion Balance Test (SEBT) was used to evaluate dynamic balance. ANALYSIS: Angular differences between perturbed and non-perturbed gait cycles were used to quantify movement error. Detection threshold was defined as the minimal movement error at which 50% of the perturbations were perceived. Intraclass correlation coefficients (ICCs) estimated test-retest reliability, and Pearson coefficients were used to determine the correlation between detection threshold and SEBT. RESULTS: Detection threshold was 5.31±2.12°. Good reliability (ICC=0.70) and a moderate to strong correlation to SEBT (r=-0.57 to -0.76) were found. CONCLUSION: Force perturbations produced by the robotized AFO provides a reliable way of evaluating proprioception during walking.