The authorship of disguised handwriting written with the unaccustomed hand: A preliminary study

Sometimes, a writer may try to disguise their normal handwriting to hide their identity. One of the most effective and less frequent modes of disguise is to write with the un-accustomed hand. In this type of disguise, due to a sudden loss of pen control, pictorial appearance of handwriting changes to such an extent that the writer assumes success and gets convinced that the disguised handwriting they have produced cannot be attributed to them by comparison with their normal writing style. In the present study, handwriting samples of several persons, both with the normal hand and the unaccustomed hand, were obtained and an attempt has been made to find out and identify those features that survive the hazards of disguise and could be helpful to accurately determine the authorship of such disguised handwriting in comparison with one’s normal handwriting samples. A detailed study of letter-forms, the connecting strokes between letters, and t-crossing written by several persons has been carried out. It has been found that, despite pictorial dissimilarities, there are certain unconscious features that are rarely disguised which could either form the basis for their association with a particular writer or indicate its probability for further investigation. The analysis, comparison, and evaluation of features unconsciously left by the writer, including the parameters selected for the present study, can be carried out by a trained forensic document examiner; and they can give whatever opinion is possible and justifiable in facts and circumstances of a case.

Design and Performance Evaluation of a Hybrid Hand Exoskeleton for Hand Opening/Closing

Finger extensor muscle weakness and flexor hypertonia are the most commonly reported issues among patients suffering from amyotrophic lateral sclerosis (ALS). Moreover, the relative hyperflexion of the wrist and the fingers has limited their ability to open the hand and interact with the external environment voluntarily. In this work, a hybrid hand exoskeleton is developed to prevent the relative hyperflexion of the fingers and wrist and facilitate the users in their functional hand opening by compensating the flexor hypertonia. This exoskeleton, combining a passive device with the soft extra muscle (SEM) glove, assists users in normal hand opening/closing required for some basic activities of daily living. The paper presents kinematic and static models of passive hand exoskeleton design. Moreover, the proposed design is tested and evaluated by comparing the volunteer hand opening with the exoskeleton assistance using the flex sensors attached on the dorsal side of the middle finger, ring finger, and thumb with both healthy subjects and patients.

Long-term sensibility outcomes of secondary digital nerve reconstruction with sural nerve autografts: a retrospective study

Background Recovery of sensibility after digital nerve injury is crucial for restoring normal hand function. We evaluated long-term outcomes of digital nerve reconstruction with autografts. Methods This retrospective study included patients who underwent secondary reconstruction of digital nerves with nerve autografting. Recovery of sensibility was evaluated based on the following: patient self-assessment, two-point discrimination (2PD), and a total sensation score (sum of proprioception, temperature sensation, and sharp/dull discrimination). Mixed models regression was used to study predictors of sensibility outcomes. The predictors analyzed were age, sex, smoking status, number of fingers involved in a patient (as a measure of injury severity), time to reconstruction, and time to follow-up. Results In 61 patients, 174 digital nerves in 126 fingers were reconstructed after an average of 33.1 weeks from injury. The mean follow-up was 6.4 years from reconstruction. The mean graft length was 3.6 cm. Self-rated sensibility in the affected area was very good in 13% of patients, good in 33%, satisfactory in 40%, and poor in 24%. 2PD at 6 mm was present in 17% of patients, at 10 mm in 12%, and at 15 mm in 18% (mean 2PD was 10.8). Proprioception was preserved in 107 (85%) fingers, sensation of temperature was preserved in 99 (75%) of fingers, and sharp/dull discrimination in 88 (70%) fingers. Time from injury to reconstruction was the only significant predictor of the total sensation score. Conclusion Our data indicate that earlier reconstruction is associated with a favorable outcome.

Human Anthrax in Dolj County, Romania—A Series of Three Cases

Bacillus anthracis is the causative agent of anthrax, primarily a disease of herbivorous animals, which can be accidentally transmitted to humans. Three cases of cutaneous human anthrax were recorded in August 2020 in Dolj county, Romania. These cases included livestock farmers (husband and wife, as well as a man from their entourage). The women presented malignant edema, which required surgery for compartment syndrome; and the men presented the common form of cutaneous anthrax. According to the laboratory investigation, two cases complied with the criteria in the case definition. All cases were successfully treated with antibiotics and the women received reconstructive plastic surgery of the skin defects, restoring normal hand function. The contact with sick animals was ruled out by the health authorities concluding that it was the contamination of pre-existing skin lesions with B. anthracis spores from the soil, the anthracogenic area.

Thermotography of the hands of a healthy person as a basis for thermal diagnosis (narrative review)

This is a narrative literature review of current status of normal hand thermography, methods and technique of their acquisition and analysis. Some physiological processes underlying the thermography picture formation also discussed.

Flexion Angles of Finger Joints in Two-Finger Tip Pinching Using 3D Bone Models Constructed from X-Ray Computed Tomography (CT) Images

The motion analysis of two-finger tip pinching using the thumb and index finger provides crucial data for designing the motion mechanism of electric prosthetic hands. The purpose of this study is to determine the joints that have high mobility during two-finger tip pinching by measuring the flexion angle of each joint. Ten Japanese men with normal hand were selected. CT images were obtained while the hands adopted the following four postures: a basic posture not pinching a cylinder, and three postures pinching wooden cylinders with different diameters (2, 10, and 30 mm). Three-dimensional bone models of the thumb and index finger were created using the CT images and used to measure the flexion angles of the joints. The flexion angles of the proximal interphalangeal and metacarpophalangeal joints of the index finger significantly decreased as the diameter of the cylinder increased. However, even when the diameter of the cylinder changed, the flexion angle of the distal interphalangeal joint of the index finger, and the flexion and rotation angles of all of the thumb joints did not change. When pinching objects of different sizes with a two-finger tip pinch, the posture of the thumb is fixed, and only the posture of the index finger changes. When designing the two-finger tip pinch motion for an electric prosthetic hand, it is sufficient to drive the joints of the index finger only.

Appearance of Congenital Hand Anomalies

Background and Aims: Impact of appearance of congenital hand anomalies has not previously been reported. The purpose of this study was to describe the common perception about how different congenitally malformed hands look. Material and Methods: We developed a questionnaire in a game format to evaluate the appearance of different hands. Altogether 1450 (954 females) 4- to 84-year-old residents (296 children) of two European and one Asian (n = 102) country were asked to rate the appearance of different looking hands on a five-point pictorial Likert-type scale. Standardized photographs of the dorsal aspect of 17 different congenitally malformed non-operated hands and a normal hand were presented to respondents. Significance of age, gender, nationality, and profession of the respondents was assessed. Results: The respondents’ ranking order of the hands was nearly consistent. The normal hand (mean = 4.43, standard deviation = 0.85, Md = 5) and clinodactyly (mean = 4.37, standard deviation = 0.86, Md = 5) were perceived to have the best appearance. Symbrachydactyly (mean = 1.42, standard deviation = 0.68, Md = 1) and radial club hand (mean = 1.40, standard deviation = 0.68, Md = 1) received the lowest scores. Adults rated the appearance of hands higher than children regarding 14 hands, females higher than men regarding 15 hands, and Europeans higher than Asians in 4 hands (p < 0.05, respectively). Europeans rated four-finger hand (mean = 3.21, standard deviation = 1.18, Md = 3) better looking than six-finger hand (mean = 2.92, standard deviation = 1.18, Md = 3, p < 0.005), whereas Asians gave higher scores to six-finger hand (mean = 2.66, standard deviation = 1.26, Md = 3) compared to four-finger hand (mean = 2.51, standard deviation = 1.14, Md = 2). Medical doctors and nurses gave higher scores compared to the other profession groups, school children, and high school students in five hands (p < 0.05). Conclusion: A normal hand is perceived distinctly better looking than most congenitally different hands. Different malformations’ appearance was ranked very coherently in the same order despite of participants’ age, gender, nationality, or profession. Asians seem to prefer an additional digit to a four-finger hand.

3-D Printed Orthotic Hand With Wrist Mechanism Using Twisted and Coiled Polymeric Muscles

Most stroke victims undergo muscular disorders leading to weakening of muscles and inability to perform normal hand activities. An exoskeleton device is therefore needed to aid in performing basic hand movements to improve the quality of life of the victims. Most of the available devices in literature are controlled using electrical motors with a rigid structure and complex design. This paper discusses the design and performance of an inexpensive and lightweight 3D printed orthotic device featuring a wrist mechanism. The design is simple and utilizes twisted and coiled polymeric (TCP) muscles which are easy to fabricate using a silver coated nylon 6, 6 threads. The device facilitates the movement of all the three joints of the human finger namely, distal interphalangeal joint (DIP), proximal interphalangeal joint (PIP) and the metacarpophalangeal joint (MCP). Experiments were performed using a custom-made hand which was 3D printed and casted using silicone rubber with a shore hardness 10 (Ecoflex® 010) to resemble an actual human hand. The results showed the range of motion achieved with the device, grasping and pinching of various objects with assistive efforts using TCP muscles and demonstrated the capability of the device to achieve flexion and extension of the fingers mimicking the human finger movements.

Supernumerary Robotic Fingers as a Therapeutic Device for Hemiparetic Patients

Patients with hemiparesis often have limited functionality in the left or right hand. The standard therapeutic approach requires the patient to attempt to make use of the weak hand even though it is not functionally capable, which can result in feelings of frustration. Furthermore, hemiparetic patients also face challenges in completing many bimanual tasks, for example walker manipulation, that are critical to patients’ independence and quality of life. A prototype therapeutic device with two supernumerary robotic fingers was used to determine if robotic fingers could functionally assist a human in the performance of bimanual tasks by observing the pose of the healthy hand. Specific focus was placed on the identification of a straightforward control routine which would allow a patient to carry out simple manipulation tasks with some intermittent input from a therapist. Part of this routine involved allowing a patient to switch between active and inactive monitoring of hand position, resulting in additional manipulation capabilities. The prototype successfully enabled a test subject to complete various bimanual tasks using the robotic fingers in place of normal hand motions. From these results, it is clear that the device could allow a hemiparetic patient to complete tasks which would previously have been impossible to perform.