[Musculoskeletal disorders of the knee of workers]

50% of workers have been or will be affected by knee pains and complaints will be more frequent as the population ages and careers will be longer. The increase in prevalence depends on mechanical or morphological causes as well as psychosocial state and work organization. Lesions of the meniscus, well known for a long time, seem to be stable in the statistics of Social Security as well as the hygroma; the use of knee-pads (overalls with built-in cushions) is strongly recommended while working in kneeling or squatting position, even DIY activities. Are particularly dangerous: the squatting or kneeling position extended for longer than one hour a day, often recovering from these two positions (more than 30 times a day), lifting or carrying heavy loads, often climbing (around 30 times per day) stairs or ladders. These gestures and postures are unavoidable in some jobs; in those cases, advices given by the specialist of occupational medicine and the ergonomist may improve or alter the habits of the worker or of his entire team. The prevention of overweight and the habit of carrying heavy loads must be amplified, for all the usual positions of work. Consulting to decide about the return to work after surgery for knee replacement will be more frequent. Then, as each time work can interfere with health, it is logical that the family doctor have (via the patient) links with the specialist of occupational medicine, which holds valuable information for quality of life of employees.