UK FROST

Management of adults with primary frozen shoulder in secondary care (UK FROST): a multicentre, pragmatic, three-arm, superiority randomised clinical trial.

Rangan A, Brealey SD, Keding A, et al. Lancet (London, England) 2020 · PMID 33010843 · doi:10.1016/s0140-6736(20)31965-6

Question

Which is most effective for primary frozen shoulder: arthroscopic capsular release, manipulation under anaesthesia, or early structured physiotherapy?

Design

Pragmatic three-arm multicentre superiority RCT across 35 UK hospital sites with cost-effectiveness analysis.

Patients

Adults referred to secondary care with unilateral primary frozen shoulder.

Intervention

Manipulation under anaesthesia with steroid injection, or arthroscopic capsular release (steroid optional); both followed by physiotherapy

Comparison

Early structured physiotherapy with steroid injection

Primary outcome

Oxford Shoulder Score at 12 months

Key result

All three groups improved substantially; differences between them did not reach clinical importance. Capsular release carried more risk and cost, and manipulation under anaesthesia was the most cost-effective.

Limitations

Unblinded surgical comparisons and varied waiting times to surgery may have influenced results.

Impact on practice

Supports physiotherapy with injection or manipulation under anaesthesia before arthroscopic capsular release, which should be reserved for selected cases.