The Natural History of Idiopathic Frozen Shoulder: A 2- to 27-year Followup Study

The natural history of spontaneous idiopathic frozen shoulder is controversial. Many studies claim that complete resolution is not inevitable. Based on the 40-year clinical experience of the senior author, we believed most patients with idiopathic frozen shoulder might have a higher rate of resolution than earlier thought.

We determined the length of symptoms, whether spontaneous frozen shoulder recovered without any treatment, and whether restored ROM, pain relief, and function persisted over the long term.

We retrospectively reviewed 83 patients treated for frozen shoulder (84 shoulders; 56 women) 2 to 27 years (mean, 9 years) after initial consultation. The mean age at onset of symptoms was 53 years. Fifty-one of the 83 patients (52 shoulders) were treated with observation or benign neglect only (untreated group), and 32 had received some kind of nonoperative treatment before the first consultation with the senior author (nonoperative group). We also evaluated all 20 patients (22 shoulders; 13 women) with spontaneous frozen shoulder who underwent manipulation under anesthesia during the same time (manipulation group). The mean age of these patients was 49 years. The minimum followup was 2 years (mean, 14 years; range, 2–24 years). We determined duration of the disease, pain levels, ROM, and Constant-Murley scores.

The duration of the disease averaged 15 months (range, 4–36 months) in the untreated group, and 20 months (range, 6–60 months) in the nonoperative group. At last followup the ROM had improved to the contralateral level in 94% in the untreated group, in 91% in the nonoperative group, and in 91% in the manipulation group. Fifty-one percent of patients in the untreated group, 44% in the nonoperative group, and 30% in the manipulation group were totally pain free at rest, during the night, and with exertion. Pain at rest was less than 3 on the VAS in 94% of patients in the untreated group, 91% in the nonoperative group, and 90% of the manipulation group. The Constant-Murley scores averaged 83 (86%) in the untreated group, 81 (77%) in the nonoperative group, and 82 (71%) in the manipulation group, reaching the normal age- and gender-related Constant-Murley score.

We found 94% of patients with spontaneous frozen shoulder recovered to normal levels of function and motion without treatment.

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.