Performance adaptive training control strategy for recovering wrist movements in stroke patients: a preliminary, feasibility study

<p>Abstract</p> <p>Background</p> <p>In the last two decades robot training in neuromotor rehabilitation was mainly focused on shoulder-elbow movements. Few devices were designed and clinically tested for training coordinated movements of the wrist, which are crucial for achieving even the basic level of motor competence that is necessary for carrying out ADLs (activities of daily life). Moreover, most systems of robot therapy use point-to-point reaching movements which tend to emphasize the pathological tendency of stroke patients to break down goal-directed movements into a number of jerky sub-movements. For this reason we designed a wrist robot with a range of motion comparable to that of normal subjects and implemented a self-adapting training protocol for tracking smoothly moving targets in order to facilitate the emergence of smoothness in the motor control patterns and maximize the recovery of the normal RoM (range of motion) of the different DoFs (degrees of Freedom).</p> <p>Methods</p> <p>The IIT-wrist robot is a 3 DoFs light exoskeleton device, with direct-drive of each DoF and a human-like range of motion for Flexion/Extension (FE), Abduction/Adduction (AA) and Pronation/Supination (PS). Subjects were asked to track a variable-frequency oscillating target using only one wrist DoF at time, in such a way to carry out a progressive splinting therapy. The RoM of each DoF was angularly scanned in a staircase-like fashion, from the "easier" to the "more difficult" angular position. An Adaptive Controller evaluated online performance parameters and modulated both the assistance and the difficulty of the task in order to facilitate smoother and more precise motor command patterns.</p> <p>Results</p> <p>Three stroke subjects volunteered to participate in a preliminary test session aimed at verify the acceptability of the device and the feasibility of the designed protocol. All of them were able to perform the required task. The wrist active RoM of motion was evaluated for each patient at the beginning and at the end of the test therapy session and the results suggest a positive trend.</p> <p>Conclusion</p> <p>The positive outcomes of the preliminary tests motivate the planning of a clinical trial and provide experimental evidence for defining appropriate inclusion/exclusion criteria.</p

Treatment of post-traumatic degenerative changes of the radio-carpal and distal radio-ulnar joints by combining radius, scaphoid, and lunate (RSL) fusion with ulnar head replacement

Distal radial fractures are a common type of fracture. In the case of intra-articular fractures, they often result in post-traumatic arthrosis. The objective of this study is to describe a novel alternative to the established salvage techniques for the treatment of post-traumatic arthrosis of the radio-carpal and distal radio-ulnar joints (DRUJ). Six patients with radio-carpal and DRUJ arthrosis were treated with a combined radius, scaphoid, and lunate (RSL) arthrodesis and as a Herbert ulnar head prosthesis. Follow-up consisted of both radiographic and functional assessments. Functional measurements were noted both pre- and postoperatively. No non-union or pseudoarthrosis was seen; neither did any of the ulnar head prostheses show loosening. Clinical examination showed an improvement in strength, pain, and range of movement, as well as a decrease in disability. Combining RSL arthrodesis with a Herbert ulnar head prosthesis, which deals with pain while retaining partial wrist movement, can be an alternative to established salvage procedures