The demand for a concept for workplace analysis in connection with vertebral column stress has been the main reason for development of the originally software Apalys to meet the increasing and demanding requirements in the field of industrial safety. The basic idea was to shoot a video recording at the workplace to be analyzed by means of a videocamera. Single images of interest are digitized and processed by the program. Spine problems caused by lifting and carrying heavy loads during occupational activities are frequent diseases. Apart from load and exposure time it is the body posture that has a high influence of the stress. So far data for the calculation of vertebral column stress have been determined by analyses on the spot. A computer-aided image analysis preferably by video recordings allows a determination of the body posture. Furthermore with data of bodyweight, bodyheight and weight of the load the load limit recommended according to NIOSH, determining the force exerted on the lumbar column, could be calculated. For a long time it was used just to sensitize and teach workers for using a correct or better lifting technique.
Later, the idea was born to make an app for easy and fast load calculation.
The app "Heben und Tragen", translated into English language just “lift and carry", is used to calculate the vertical pressure load on the Spine segment L5/S1. The result is due to the posture, demographic information, and the load weight displayed numerically and graphically in the form of a three-grade scale and can be sent via email to a recipient. Additionally the user get advice for correct lifting technique and links to more information of ergonomic workplace design and sequences.
The vertical pressure load is in the literature in addition to postures the criterion for the long-term musculoscelettal diseases. The app calculates on the basis of photographing a person and the marking of the lumbar spine, shoulder, elbow and hand the vertical pressure load on the vertebral segment L5/S1 of a person during a single lift or holding the load. Basis of the analysis is a biomechanical model which relates the vertical force components , torques of the load of the upper body and the lumbar back muscles to the vertebral segment L5/S1. Vertical power components and torques in relation to body posture will be considered for calculation. An analysing score based on the “Dortmunder benchmarks"(gender – and age-dependent scales which declare limits for pressure loads on segment L5/S1) will be presented in a three-point scale and valued. Depending on evaluation one of three possible recommendations will be given. The report can be sent via e-mail, the analysis are privacy and not stored on the device.
