Not infrequently it happens that as a result of an injury or infection a soldier has to be invalided out of the Army on account of the partial or total loss of the index finger, or of its impaired mobility through ankylosis of the smaller joints. Though the injury is often trivial and the man is perfectly fit otherwise, not being able to grip the rifle and pull the trigger efficiently, he is us...

A simple method is developed for robustly estimating a fixed dominant axis of rotation (AoR) of anatomical joints from surface marker data. Previous approaches which assume a model of circular marker trajectories use plane fitting to estimate the direction of the AoR. However, when there is limited joint range of motion and rotation due to a second degree of freedom, minimizing only the planar ...

© 2007 Association médicale canadienne T surgeon’s knot is a well-established knot in surgical practice, known to provide unsurpassed grip and security for the tissue tied. It is particularly useful with slippery monofilament suture materials. Traditional tying of the surgeon’s knot involves a cumbersome technique of repeating throws to complete the double loops of each hitch. We describe a 2-h...

Prohibitive voice behaviors are employees’ expressions of concern about practices, incidents, or behaviors that may potentially harm the organization. In this study, we examined a potential biological correlate of prohibitive voice: prenatal exposure to testosterone. In a sample of bankers, we used 2D:4D (i.e., the ratio of the length of the index finger to the length of the ring finger) as a m...

We analyzed the adaptability of human thumb and index finger movement kinematics and dynamics to variations of precision grip aperture and movement velocity. Six subjects performed precision grip opening and closing movements under different conditions of movement velocity and movement aperture (thumb and index finger tip-to-tip distance). Angular motion of the thumb and index finger joints was...

Individual digit-tip forces and moments during torque production on a mechanically fixed circular object were studied. During the experiments, subjects positioned each digit on a 6-dimensional force/moment sensor attached to a circular handle and produced a maximum voluntary torque on the handle. The torque direction and the orientation of the torque axis were varied. From this study, it is con...