Faculty Bibliography

The Modular Prosthetic Limb (MPL) was examined for its feasibility and usability as an advanced, dexterous upper extremity prosthesis with surface electromyography (sEMG) control in with two individuals with below-elbow amputations. Compared to currently marketed prostheses, the MPL has a greater number of sequential and simultaneous degrees of motion, as well as wrist modularity, haptic feedback, and individual digit control. The MPL was successfully fit to a 33-year-old with a trans-radial amputation (TR01) and a 30-year-old with a wrist disarticulation amputation (TR02). To preserve anatomical limb length, we adjusted the powered degrees of freedom of wrist motion between users. Motor training began with practicing sEMG and pattern recognition control within the virtual integration environment (VIE). Prosthetic training sessions then allowed participants to complete a variety of activities of daily living with the MPL. Training and Motion Control Accuracy scores quantified their ability to consistently train and execute unique muscle-to-motion contraction patterns. Each user also completed one prosthetic functional metric-the Southampton Hand Assessment Procedure (SHAP) for TR01 and the Jebsen-Taylor Hand Function Test (JHFT) for TR02. Haptic feedback capabilities were integrated for TR01. TR01 achieved 95% accuracy at 84% of his VIE sessions. He demonstrated improved scores over a year of prosthetic training sessions, ultimately achieving simultaneous control of 13 of the 17 (76%) attempted motions. His performance on the SHAP improved from baseline to final assessment with an increase in number of tasks achieved. TR01 also used vibrotactile sensors to successfully discriminate between hard and soft objects being grasped by the MPL hand. TR02 demonstrated 95% accuracy at 79% of his VIE sessions. He demonstrated improved scores over months of prosthetic training sessions, however there was a significant drop in scores initially following a mid-study pause in testing. He ultimately achieved simultaneous control of all 13 attempted powered motions, and both attempted passive motions. He completed 5 of the 7 (71%) JHFT tasks within the testing time limit. These case studies confirm that it is possible to use non-invasive motor control to increase functional outcomes with individuals with below-elbow amputation and will help to guide future myoelectric prosthetic studies.

Following the administration of brachial plexus anesthesia for right thumb carpometacarpal arthroplasty with ligament reconstruction, a 54-year-old woman with all limbs intact developed phantom limb sensations, including the misperception of the placement of her right arm and frozen limb sensations in her fingers. Immobility of her fingers in a stacked position was experienced for ~3.5 days after surgery, and she described her phantom sensations as the hand experiencing "tingling" and feeling "heavy." While the onset of these phantom sensations occurred almost immediately after administration of brachial plexus anesthesia, they lasted for ~69 h after anesthesia wear off, suggesting that cortical effects from denervation resolves much more slowly than initial remapping, giving insight into the mechanisms behind phantom limb sensations that are often experienced by amputees.

There are over two million individuals living with amputations in the United States. Almost all will experience the feeling of the amputated limb as still present, termed phantom limb sensation (PLS). Over 85% will also experience excruciatingly painful sensations known as phantom limb pain (PLP). Additionally some amputees also experience a sensation of the phantom limb in which the limb is immobile or stuck in a normal or abnormal anatomical position, termed frozen phantom sensations. When an amputee experiences a frozen limb they report that they are unable to move the limb, and sometimes report sensations of cramping and pain along with this immobility, fortunately not all frozen limbs are painful. Such sensations have previously been attributed to proprioceptive memories of the limb prior to amputation or a mismatch between visual feedback and proprioceptive feedback resulting from the initiation of a movement. Unfortunately there has been a dearth of research specifically focused on the frozen PLS. We conducted a survey to better elucidate and understand the characteristics and experiences of frozen PLSs. Results from the survey provided descriptions of a variety of frozen limb experiences, such as position and feelings experienced, combined with other phantom pain sensations, casting doubt on previous theories regarding frozen limbs. Further research needs to be focused on the etiology of phantom sensations and pain, which may not necessarily be maintained by the same processes, in order to understand better ways to treat PLP, increase mobility, and enhance amputees quality of life.

OBJECTIVE:To examine whether blast exposure alone and blast-associated concussion result in similar neurologic and mental health symptoms. METHODS:A 14-item questionnaire was administered to male US Marines on their return from deployment in Iraq and/or Afghanistan. RESULTS:A total of 2,612 Marines (median age 22 years) completed the survey. Of those, 2,320 (88.9%) reported exposure to ≥1 blast during their current and/or prior deployments. In addition, 1,022 (39.1%) reported ≥1 concussion during the current deployment, and 731 (28.0%) had experienced at least 1 prior lifetime concussion. Marines were more likely to have sustained a concussion during the current deployment if they had a history of 1 (odds ratio [OR] 1.5, 95% confidence interval [CI] 1.2-2.0) or ≥1 (OR 2.3, 95% CI 1.7-3.0) prior concussion. The most common symptoms were trouble sleeping (38.4%), irritability (37.9%), tinnitus (33.8%), and headaches (33.3%). Compared to those experiencing blast exposure without injury, Marines either experiencing a concussion during the current deployment or being moved or injured by a blast had an increased risk of postinjury symptoms. CONCLUSIONS:There appears to be a continuum of increasing total symptoms from no exposure to blast exposure plus both current deployment concussion and past concussion. Concussion had a greater influence than blast exposure alone on the presence of postdeployment symptoms. A high blast injury score can be used to triage those exposed to explosive blasts for evaluation.

The emerging field of teleneurology is delivering quality care to neurologic patients in increasingly numerous technologies and configurations. Teleneurology is well-positioned to address many of the logistical issues neurologists and their patients encounter today. However, formalized medical training has not caught up with this developing field, and there is a lack of formal education concentrating on the specific opportunities and challenges of teleneurology. Considering this, the American Academy of Neurology Telemedicine Work Group identified equivalencies with which any practitioner of teleneurology should be familiar. The purpose of this curriculum is not to define teleneurology or mandate where its use is appropriate, but rather to provide guidance on basic equivalencies that students, residents, and practitioners should know while practicing teleneurology. Comprehensive training in clinical bedside neurology is necessary to safely practice teleneurology and the components of this curriculum are an extension of that training. In this article, we offer a detailed discussion on the rationale for the contents of this curriculum and conclude by providing a model curriculum and an outline for evaluating residents in teleneurology.