Background: After stroke, ankle proprioceptive deficits are common and do not typically correlate with ankle weakness. Some studies report that these deficits correlate with gait function, supporting the importance of somatosensory input for gait control. Others have not found a relationship, possibly due to use of coarse proprioception measures. Robotic assessments of proprioception offer improved consistency and sensitivity. Objective: To establish relationships between ankle proprioception, gait function, and ankle motor in stroke survivors. Methods: We studied 39 individuals in the chronic phase of stroke using 2 robotic tests, Crisscross and Joint Position Reproduction (JPR), to quantify ankle proprioception. We examined associations of these measures with gait speed (10-meter walk test) and gait endurance (6-minute walk test). We also analyzed correlations with lower extremity motor impairment, including robotic measures of ankle strength (MVC) and active range of motion (AROM), and the lower extremity Fugl-Meyer exam (LEFM). Results: Impaired ankle proprioception was present in 87% of participants. Crisscross error weakly correlated with the 10mWT gait speed (ρ = −0.20, P = 0.23) and 6MWT distance (ρ = −0.28, P = .089). JPR error weakly correlated with 10mWT gait speed (ρ = −0.29, P = .092) and significantly correlated with 6MWT distance (ρ = −0.34, P = .04). No significant correlations were observed between ankle proprioceptive error and MVC, AROM, or LEFM ( P > 0.2). Conclusion: These results confirm the presence of a weak relationship between ankle proprioception and gait after stroke that is independent of several common measures of motor impairment.
In rehabilitation research, coarse clinical outcome measures may limit the sensitivity of trials by failing to detect meaningful intervention-induced changes. Sensorized robotic platforms can potentially improve the evaluation of motor function, yet their reliability compared to skilled therapists remains unclear. This study utilized a robotic device to measure two fundamental impairments that are critical to ankle function: range of motion (ROM, active and passive) and dorsiflexion maximum voluntary contraction (MVC). In 34 chronic hemiparetic post-stroke individuals, we assessed test–retest reliability over two days for the robot and experienced therapists, who used a goniometer and manual muscle testing (MMT). We also evaluated robotic test–retest reliability in 36 young and 26 older unimpaired adults. Reliability for robotic and therapist-based AROM and MVC measures was high (ICC > 0.86), consistent across all groups. Robotic AROM and PROM measurements correlated strongly with therapist assessments (r > 0.60, p < 0.001) but were 120% and 37% larger than therapist assessments (p < 0.001), respectively. For the MVC measurement, the therapist assigned 85% of participants a score of 1 on the MMT, but their MVC torque was distributed from 0 to ~20 Nm. Measurement differences between methods likely arose from the robot’s constrained setup, allowing for compensatory muscle activation. The increased granularity provided by robotic MVC measurements could enable more precise tracking of motor recovery and facilitate tailored rehabilitation strategies. These results support the clinical utility of robotic platforms for ankle assessment, offering detailed, objective measurements that can augment traditional evaluations, and provide a benchmark dataset for other researchers.
In rehabilitation research, coarse clinical outcome measures may limit the sensitivity of trials by failing to detect meaningful intervention-induced changes. Sensorized robotic platforms can potentially improve the evaluation of motor function, yet their reliability compared to skilled therapists remains unclear. This study utilized a robotic device to measure two fundamental impairments that are critical to ankle function: range of motion (ROM, active and passive) and dorsiflexion maximum voluntary contraction (MVC). In 34 chronic hemiparetic post-stroke individuals, we assessed test-retest reliability over two days for the robot and experienced therapists, who used a goniometer and manual muscle testing (MMT). We also evaluated robotic test-retest reliability in 36 young and 26 older unimpaired adults. Reliability for robotic and therapist-based AROM and MVC measures was high (ICC > 0.86), consistent across all groups. Robotic AROM and PROM measure-ments correlated strongly with therapist assessments (r > 0.60, p < 0.001) but were 120% and 37% larger than therapist assessments (p < 0.001), respectively. For the MVC measurement, the therapist assigned 85% of participants a score of 1 on the MMT, but their MVC torque was distributed from 0 to ~20 Nm. Measurement differences between methods likely arose from the robot's constrained setup, allowing compensatory muscle activation. The increased granularity provided by robotic MVC measurements could enable more precise tracking of motor recovery and facilitate tailored rehabilitation strategies. These results support the clinical utility of robotic platforms for ankle assessment, offering detailed, objective measurements that can augment traditional evaluations. A supplementary dataset for benchmarking future research is provided.