Symptomatic ankle arthrosis affects 1-4% of the population, and the most common aetiology is post-traumatic. Symptoms include pain, swelling and reduced range of motion. Diagnosis is based on weight-bearing X-rays of the ankle joint, and treatment depends on the arthrosis grade and patient characteristics. Non-operative therapy, i.e. physiotherapy, analgesics, injection therapy and/or braces/orthoses is first-line treatment, as we argue in this review. Arthroscopy can be an effective treatment for some patients, but in case of severe arthrosis, osteotomies, total ankle replacement or arthrodesis may be necessary.