On the island of Gotland and in the city of Malmö, the prevalence of coxarthrosis was calculated using the hip projections in colon roentgen examinations. The prevalence of coxarthrosis among the Gotland islanders was about twice that of the Malmö urbanites, and the condition became obvious earlier in life. The population of the local Gotland city of Visby did not contribute to this difference; the difference was entirely due to an increased incidence in the rural population of the island. Heavy labor in conjunction with farming is believed to be the cause of the deviation.