The historical evolution of the Sharp-Purser Test: how a rheumatology observation became an OMPT screening tool

Objectives The Sharp-Purser Test (SPT) is widely taught in orthopaedic manual physical therapy (OMPT) to screen for upper cervical instability. This commentary synthesizes historical literature to clarify the SPT's origin, clinical expansion, and current limitations.Methods A narrative historical review examined primary source literature across rheumatology, neurology, and physical therapy. Foundational descriptions, diagnostic accuracy studies, expert consensus papers, systematic reviews, and case applications were evaluated.Results Sharp and Purser's 1961 paper described a manual observation of C1–C2 translation in inflammatory arthropathies rather than a formal test. Aspinall introduced the SPT to physical therapy in 1990 as a safety-oriented screening maneuver, building on Uitvlugt and Indenbaum’s 1988 validation work. Subsequent research revealed low interrater reliability, variable diagnostic accuracy, and poor expert consensus. Systematic reviews show high specificity but inconsistent sensitivity.Discussion/Conclusion The SPT transitioned from a niche rheumatological observation to a standard OMPT screening tool without robust evidentiary support. Clinicians should interpret the SPT cautiously as part of a multimodal assessment rather than a standalone measure of upper cervical instability.