Painfull skeletal disorders are susceptible to be treated with low-dose radiotherapy. DEGRO guidelines recommend a dose between 3 and 6 Gy at 0'5 Gy/fraction or 1 Gy/fraction respectively. The investigators want to verify that both treatments (3 and 6 Gy) are similar to improve the pain and function in patiens with gonarthrosis and coxarthrosis, and there are no differences between both treatments, therefore, 3 Gy is not less than 6 Gy.
In this context, a prospective multicenter study is proposed. The study will include 338 patients to assess the efficacy of low dose irradiation (3 vs 6 Gy) in gonarthrosis and coxarthrosis.

