Two-hundred and sixty-nine shoulders in 223 patients with a diagnosis of primary frozen shoulder were studied. The main outcome measure was the Oxford shoulder score. The mean follow-up from symptom onset was 4.4 years (range, 2-20 years). The mean age at symptom onset was 53.4 years; with women affected more commonly than men (1.6:1.0).Twenty percent of patients reported bilateral symptoms, but there were no recurrent cases. In the long term, 59% of patients had normal or near normal shoulders and 41% reported some ongoing symptoms. The majority of these persistent symptoms were mild (94%), with pain being the most common complaint. Only 6% had severe symptoms with pain and functional loss.Those with the most severe symptoms at condition onset had the worst long-term prognosis, P < .001. Two-hundred and sixty-nine shoulders in 223 patients with a diagnosis of primary frozen shoulder were studied. The main outcome measure was the Oxford shoulder score. The mean follow-up from symptom onset was 4.4 years (range, 2-20 years). The mean age at symptom onset was 53.4 years; with women affected more commonly than men (1.6:1.0).Twenty percent of patients reported bilateral symptoms, but there were no recurrent cases. In the long term, 59% of patients had normal or near normal shoulders and 41% reported some ongoing symptoms. The majority of these persistent symptoms were mild (94%), with pain being the most common complaint. Only 6% had severe symptoms with pain and functional loss.Those with the most severe symptoms at condition onset had the worst long-term prognosis, P < .001.