Quantifying hand grip strength and force distribution in cardiologists using a multi-sensor force-sensitive surgical glove

Anthropometric measurement Anthropometric measurements including hand size, limb lengths, height and standard hand grip strength were collected. These served as baseline metrics for benchmarking our findings. Analogue anthropometric measurements and grip strength were obtained from participants to use as baseline measurements. Height, limb lengths and grips strength measurements were gathered by a Human Factors Engineer who was trained on techniques for anthropometric database establishment according to ISO 7250-1:2017. An Einscan Pro 2X 3D scanner was used to gather participant hand measurements. Participants sat in a chair with their arm resting upright on the armrest. 3D scans were imported into Microsoft 3D builder for measurement extraction. Extractions were performed using biomarkers as defined in ISO 7250-1:2017. Force data Participants applied axial force to a handle mounted on a through-hole load cell (Futek FSH04825) affixed to an adjustable angle mounting plate (Thorlabs AP180). Handles were secured to a 5.5 mm diameter rod. The handles had a length of 150 mm and were 3D-printed using PLA. For smaller diameters, a section of 6 mm InLine sheath (constructed of stainless-steel coil wire embedded in Pebax with a PTFE liner) from an Evolut FX delivery catheter was utilised. The angled plate was mounted on a 2 mm thick composite board, which was clamped to a fixed-height bench (996 mm). Participants were instructed to exert maximum voluntary effort using their right hand under various test conditions. Prior to each trial, they gradually increased force to their maximum and sustained it for at least three seconds before releasing. The force applied was intended to represent an effort level that could be maintained repeatedly over an average 8-hour workday. To prevent participants from leveraging additional force using the test bench, their left hand was either placed on their hip or left hanging freely at their side. The independent variables in the study were handle angle, diameter, and grasp type, while the dependent variables were input and output forces. Input forces referred to the forces exerted by different segments of the hand, measured using force-sensitive surgical gloves, whereas output forces represented the forces recorded at the handle end via the load cell. The study examined three grasp types: cylindrical power (CP), tripod pinch (TP), and digit-1 digit-2 precision pinch (PP).