Routine X-rays for suspected frozen shoulder offer little over diagnosis based on history and clinical examination...

Frozen shoulder is a common condition, and current guidelines state that it is a diagnosis of exclusion. Along with a history and clinical examination, routine X-ray is mandated, to rule out any "masquerading" pathology such as fracture, dislocation, metastatic lesions or severe osteoarthritis. Despite the certainty of the guidelines there is a lack of evidence to support the use of routine X-rays in this situation.

A retrospective review was performed of all X-rays obtained in the diagnosis of frozen shoulder between February 2014 and August 2017 in an integrated musculoskeletal interface service. Results were screened and the prevalence of masquerading pathology was determined.

A total of 350 shoulder X-rays that had been performed for patients with a provisional diagnosis of frozen shoulder were reviewed. Of these, 213 were from female patients (60.9%), the mean age was 57.7 (standard deviation 10.4) years and 342 (97.7%) did not have any concerning features. Six (1.7%) had severe osteoarthritis, one (0.3%) had a fracture and one (0.3%) had a lucency. All eight patients with masquerading pathology had findings from the history and clinical examination which would have warranted an X-ray, regardless of a differential diagnosis of frozen shoulder.

The findings of this retrospective review of a large number of X-rays do not support the requirement of a routine X-ray to rule out masquerading pathology to confirm the diagnosis. The data suggest that it is unnecessary for patients without a relevant clinical history suggestive of serious or masquerading pathology to undergo routine imaging.