Extension of measured value register of knee stress work activities (GonKatast)

Project No. IFA 4230


completed 09/2021


On 11 June 2019, the occupational disease "Gonarthrosis due to a task performed when kneeling or comparable knee stress with a cumulative exposure time of at least 13,000 hours over one’s working life and a minimum exposure time of at least one hour per shift" was added to the list of occupational diseases.

The scientific justification lists two key criteria for evaluating the occupational prerequisites: the angle of the knee in tasks placing stress upon the knees and the amounts of time spent doing such tasks per shift. Because there were hardly any sufficiently reliable findings concerning both factors at the time, the Institute for Occupational Safety and Health (IFA) of the German Social Accident Insurance (DGUV) worked in cooperation with several accident insurance institutions to set up a register of measured values using the CUELA measuring system (project 4138 GonKatast).

The aim of this register was to compile valid data on the quantification of relevant knee stresses within different occupational groups and to create a basis for preventative measures as well as for work-related investigations in the context of the OD determination procedures. Since then, the medical history software "knee joint diseases" with the data stored in the register has been used by many accident insurance institutions, as evidenced, among other things, by the great demand for software training at the IFA. In recent years, it transpired that, alongside the 17 occupations involving tasks placing stress upon the knees named in the scientific justification and the task modules listed in the register, many other occupations and tasks also appear frequently in reports of suspected ODs. For this reason, the register of measured values should be expanded to include more occupations and task modules.


Under the supervision of the IFA, a working group was set up with representatives from various interested accident insurance institutions. On the basis of experience compiled over recent years in the area of reporting suspected ODs, they each named occupations and tasks relevant to them. Measurements of the tasks in the occupations of bricklayer, pipe layer/duct builder, stonemason, cleaner, furnace mason/kiln mason, motor vehicle mechatronics technician for passenger vehicle technology, agricultural and construction machinery and commercial vehicles, heating/customer service fitter, kitchen fitter, furniture fitter, electrician and horticulturist, gardener and cemetery gardener are provisionally planned. Additionally, the tasks performed by educators are also of interest. The accident insurance institutions will establish contact with companies and test persons interested in the project. The measurement of shifts and activities will be undertaken by measuring teams from the accident insurance institutions, who are trained in dealing with and operating the CUELA measuring system at the IFA. The measurement data will be supplemented by data collected using questionnaires. Due to the expected scatter of the measurement data, at least three measurements should be performed for each task module to be created. All measurement data will be collected in a database, evaluated and prepared in a register format at the IFA so that it can then be made available in the accident insurance institutions’ "IFA medical history software – knee stresses".


Due to the constraints posed by the coronavirus epidemic, the intended measurements were only performed in part over the course of the project. However, there are sufficient measurements available to create task modules for several occupations: Tasks in agriculture and forestry (strawberry harvesting, milking, coniferous wood harvesting), in automotive mechatronics workshops (changing wheels) and those of educators in preschools. The results currently available for the complete task modules will be published in the form of an update to the IFA report "GonKatast – register of measured values for tasks placing stress upon the knees" and included in the register of the IFA medical history software. As before, there is still a need within the accident insurance institutions for register data on occupational diseases affecting the knees. Further representative measurements should be performed in a follow-up project in order to develop and supplement new task modules.

Last Update:

25 Jan 2022


Financed by:
  • Deutsche Gesetzliche Unfallversicherung e. V. (DGUV)
Research institution(s):
  • Institut für Arbeitsschutz der Deutschen Gesetzlichen Unfallversicherung (IFA)
  • BG BAU - Berufsgenossenschaft der Bauwirtschaft
  • Berufsgenossenschaft Energie Textil Elektro Medienerzeugnisse (BGETEM)
  • Berufsgenossenschaft Handel und Warenlogistik (BGHW)
  • Berufsgenossenschaft Holz und Metall (BGHM)
  • Sozialversicherung für Landwirtschaft, Forsten und Gartenbau

-cross sectoral-

Type of hazard:

work-related diseases, mechanical hazards


occupational disease, risk assessment, measuring methods

Description, key words:

occupational disease (OD 21 12, 2102, 2105), knee joint diseases, gonarthrosis, tasks placing stress upon the knees (squatting, kneeling, sitting seiza-style, crawling), register of measured values, CUELA measurement system, occupational stress profiles, task modules, OMEGA database, medical history software, work-related medical history in OD determination procedures, exposure assessment