Muscular Forces and Joint Angles in Small-Handed Pianists: A Pilot Study on the 7/8 Size Keyboard versus the Full Size Keyboard

This pilot study examined whether the use of a 7/8 keyboard contributed to the physical ease of small-handed pianists in comparison with the conventional piano keyboard. A secondary research question focused on the transition from one keyboard to the other. For the purposes of this study, we adopted David Steinbuhler’s postulated hand span of 8 inches or less as defining a “small-handed” pianist. The goal was to measure muscle loading and hand span during performance of the excerpt. Data collection included each participant being monitored using electromyography via surface electrodes, which were attached to the upper back/shoulder, parts of the hand and arm, and the masseter muscle of the jaw. Subjects were also fitted with electrogoniometers to capture how the span from the first metacarpophalangeal (MCP) joint to the fifth MCP joint moved according to performance demands, as well as recording wrist flexion and extension, radial and ulnar deviation. The findings were that small-handed pianists preferred the smaller keyboard and were able to transition smoothly between it and the conventional keyboard. The maximal angle of hand span while playing a difficult piece averaged about 5º smaller on the radial side and 10º smaller on the ulnar side for the 7/8 keyboard, leading to perceived comfort (ease) and better performance as rated by the subjects

Task analysis method for procedural training curriculum development

A central venous catheter (CVC) is an important medical tool used in critical care and emergent situations. Integral to proper care in many circumstances, insertion of a CVC introduces the risk of central line-associated blood stream infections and mechanical adverse events; proper training is important for safe CVC insertion. Cognitive task analysis (CTA) methods have been successfully implemented in the medical field to improve the training of postgraduate medical trainees, but can be very time-consuming to complete and require a significant time commitment from many subject matter experts (SMEs). Many medical procedures such as CVC insertion are linear processes with well-documented procedural steps. These linear procedures may not require a traditional CTA to gather the information necessary to create a training curriculum. Accordingly, a novel, streamlined CTA method designed primarily to collect cognitive cues for linear procedures was developed to be used by medical professionals with minimal CTA training. This new CTA methodology required fewer trained personnel, fewer interview sessions, and less time commitment from SMEs than a traditional CTA. Based on this study, a streamlined CTA methodology can be used to efficiently gather cognitive information on linear medical procedures for the creation of resident training curricula and procedural skills assessments

Accepted and presented at The Design of Medical Devices Conference (DMD2015)

Sociometers are wearable devices that record speech patterns, body movements, user proximities, and face-to-face interactions [1], see The potential of these devices has not been tested in unstructured and more complex environments. Research is needed to compare sociometers data against gold standards to understand their limitations and potential. The objective of this paper is to understand the limitations and potential of sociometer devices in a live in situ field disaster preparedness simulation (1) with field observation notes to see if sociometers can capture macrolevel interactions; and (2) to video recorded (ground truth) interactions to test the granularity and accuracy of sociometer data. These results may facilitate use of sociometers in similar chaotic environments with complexity and uncertainty such as the emergency department. Methods The study was conducted in a dynamic disaster preparedness simulation environment involving over 150 actors and community participants for a total of 3.4 hr Five participants from the aid station and two observers wore sociometers around the neck Each sociometer device contained a WT12 Bluetooth module Comparison of interaction data was conducted using two methods. First, observer-O1 recorded major activities real-time using an electronic tablet application. Second method compared sociometer data with a 15 min video recording of a debrief session where the group primarily remained stationary in a circle with occasionally movement observed for LD, MM, and O

Bar Clamp Having Ergonomic Handle

The present invention generally relates to a handle assembly for a hand operable bar clamp having a fixed jaw, a movable jaw and a drive for translating the movable jaw towards the fixed jaw. The assembly includes a handgrip and a trigger handle. The handgrip having an elongated rear portion has a generally rounded surface and being contoured to complement the natural transverse curve pf a human palm. The trigger handle is pivotal with respect to the handgrip. The trigger handle included an elongated front portion having a rounded front surface and being contoured to complement the natural palmer curve of a set of fingers flexed toward the palm. The shape and contour of the handle assembly cause pressure to be safely distributed across the user\u27s hand when the handgrip and the trigger handle are grasped and the trigger handle is depressed toward said handgrip

Supracutaneous vibrotactile perception threshold at various non-glabrous body loci

Researchers at the University of Nebraska–Lincoln are currently designing a wearable/portable neutron detector. As an alerting mechanism, the device will transmit vibration to the wearer’s skin in the presence of hazardous levels of neutron radiation. The present study was designed to help in the ergonomically correct body placement of the neutron detection device while providing numerical values for vibratory thresholds at the surface of various non-glabrous body loci. The aim of the study was to investigate the underlying effects of locus stimulated, amount of subcutaneous fat around a specific body site and gender on low frequency vibration thresholds. Thirty-six participants, who were categorized by both dichotomous body fat group (high or low) and gender, were tested at 24 loci orthogonally located around six body sites: head; neck; upper arm; wrist; waist; ankle. The results indicated that frequency threshold depends significantly on the locus stimulated (p = 0.001). The nape of the neck had the greatest sensitivity to low frequency stimulations, while the loci around the waist were least sensitive. Also, body fat significantly affected ability to perceive vibratory stimuli (p = 0.048), with the mean frequency threshold of the low body fat group lower than that of the high body fat group. There was no statistical difference in thresholds with gender

ERGONOMICHANDLE AND ARTICULATING LAPAROSCOPICTOOL

The present invention relates to a laparoscopic apparatus. The apparatus includes a handle having a body portion, a top surface, opposite bottom surface, a proximal and distal end. The top surface of the base is contoured to compliment the natural curve of the palm. The apparatus further includes a shaft projecting from the distal end of the handle. The shaft has a proximal and distal end. A control sphere is located on the handle. The control sphere can be moved by one or more of a user\u27s fingers to indicate direction. An end effector is located at the distal end of the shaft. The end effector is connected to the control sphere such that movements made to the control sphere control cause movement (articulations) of the end effector

Effects of passive exoskeleton support on EMG measures of the neck, shoulder and trunk muscles while holding simulated surgical postures and performing a simulated surgical procedure

Exoskeletons have shown significant impact at reducing the biomechanical demand on muscles during repetitive lifting and overhead tasks in non-healthcare industries. However, the benefits of exoskeletons are yet to be realized in the operating room, particularly as work-related musculoskeletal disorders continue to be a concern for surgeons. This study quantified the effect of using neck, arm, and trunk exoskeletons on muscle activity while assuming typical postures held in the operating room. Fourteen participants were recruited to participate in this study. In this two-part experiment participants were asked to 1) hold a series of neck flexion, arm abduction and trunk flexion postures seen in surgical procedures, and 2) perform a simulated surgical task requiring five different trunk flexion posture levels. Participants were required to complete these tasks with and without passive exoskeleton(s). This study showed that even for postures held short time periods, exoskeletons are beneficial at reducing the demand on muscles; however, the reduction in muscle demand depends on body segment and postural angle, as intended with these passive exoskeletons. Furthermore, for the simulated surgical task with awkward trunk flexion postures (10–65°), the trunk exoskeletons showed a significant reduction in the rate of rise in back muscle sEMG (+1.365%MVC/min vs. +0.769%MVC/min for non-dominant lumbar extensor muscles, p = 0.0108; +1.377%MVC/min vs. +0.770%MVC/min for the dominant lumbar extensor muscles, p = 0.0196) over 25 min, consequently resulting in improved trunk subjective discomfort scores (7.34 vs. 4.30, p < 0.05), with no impact on the neck and shoulder biomechanical demand. The results from this study indicate that exoskeletons may be a potential intervention to reduce biomechanical loading during surgery.This is a manuscript of an article published as Tetteh, Emmanuel, M. Susan Hallbeck, and Gary A. Mirka. "Effects of passive exoskeleton support on EMG measures of the neck, shoulder and trunk muscles while holding simulated surgical postures and performing a simulated surgical procedure." Applied Ergonomics 100 (2022): 103646. DOI: 10.1016/j.apergo.2021.103646. Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0). Copyright 2021 Elsevier Ltd. Posted with permission

Ergonomic redesign and evaluation of a clamping tool handle

Abstract The handle of a commercial bar clamp was redesigned using ergonomic principles and then compared with an original clamp. Ten male and ten female students participated in simulated clamping tasks under various conditions, including different clamping heights, clamping methods, and handle-gripping methods, with respect to the dependent variables of clamping and handle-squeezing forces. The results showed that the redesigned clamp produced larger clamping force with lower handle-squeezing forces than the original clamp. As expected, males exerted more force than females in both clamping and squeezing forces. A pistol grip method was superior to an upside-down handle-gripping method. Two-handed operation was recommended for this type of clamp by simultaneously pulling the trigger and sliding the bar in order to initially tighten around objects. This study shows that the application of ergonomic guidelines increases the efficiency and usability of manual handtools.