The Arm Movement Detection (AMD) test: a fast robotic test of proprioceptive acuity in the arm

I would expect this to be written into a protocol and rolled out to all stroke doctors and hospitals. Objective diagnosis of stroke deficits is something sorely lacking in stroke. With no objective diagnosis nothing can be mapped from protocols used to recovery accomplished. The key word here is objective not crap like the Rankin scale.Unless you really want the only objective point in Rankin is #6 - death.
https://jneuroengrehab.biomedcentral.com/articles/10.1186/s12984-017-0269-3

• Leigh Ann MrotekEmail authorView ORCID ID profile,
• Maria Bengtson,
• Tina Stoeckmann,
• Lior Botzer,
• Claude P. Ghez,
• John McGuire and
• Robert A. Scheidt

Journal of NeuroEngineering and Rehabilitation201714:64

DOI: 10.1186/s12984-017-0269-3

©  The Author(s). 2017

Received: 13 June 2016

Accepted: 5 June 2017

Published: 28 June 2017

Abstract

Background

We examined the validity and reliability of a short robotic test of upper limb proprioception, the Arm Movement Detection (AMD) test, which yields a ratio-scaled, objective outcome measure to be used for evaluating the impact of sensory deficits on impairments of motor control, motor adaptation and functional recovery in stroke survivors.

Methods

Subjects grasped the handle of a horizontal planar robot, with their arm and the robot hidden from view. The robot applied graded force perturbations, which produced small displacements of the handle. The AMD test required subjects to respond verbally to queries regarding whether or not they detected arm motions. Each participant completed ten, 60s trials; in five of the trials, force perturbations were increased in small increments until the participant detected motion while in the others, perturbations were decreased until the participant could no longer detect motion. The mean and standard deviation of the 10 movement detection thresholds were used to compute a Proprioceptive Acuity Score (PAS). Based on the sensitivity and consistency of the estimated thresholds, the PAS quantifies the likelihood that proprioception is intact. Lower PAS scores correspond to higher proprioceptive acuity. Thirty-nine participants completed the AMD test, consisting of 25 neurologically intact control participants (NIC), seven survivors of stroke with intact proprioception in the more affected limb (HSS+P), and seven survivors of stroke with impaired or absent proprioception in the more affected limb (HSS-P).

Results

Significant group differences were found, with the NIC and HSS+P groups having lower (i.e., better) PAS scores than the HSS-P group. A subset of the participants completed the AMD test multiple times and the AMD test was found to be reliable across repetitions.

Conclusions

The AMD test required less than 15 min to complete and provided an objective, ratio-scaled measure of proprioceptive acuity in the upper limb. In the future, this test could be utilized to evaluate the contributions of sensory deficits to motor recovery following stroke.