Representative survey of frozen shoulder questionnaire responses from the Japan Shoulder Society: What are the appropriate diagnostic terms for primary idiopathic frozen shoulder, stiff shoulder or frozen shoulder?

Abstract

Background: Primary frozen shoulder has unknown etiology and significant restriction of active and passive motion. The distinction between frozen shoulder and stiff shoulder has been unclear. Therefore, the purposes of this study were to perform a survey regarding definition and classification of frozen shoulder proposed by the American Academy of Orthopedic Surgeons (AAOS) among the members of the Japan Shoulder Society (JSS) and to compare the results with those obtained among the members of the American Shoulder and Elbow Surgeons (ASES).

Methods: The Scientific Research Project Committee of the JSS prepared the questionnaire for frozen shoulder and stiff shoulder. Surveys were sent by e-mail on Jan 14, 2016 to JSS registered members and the response dead-line was set on March 13, 2016.

Results: The number of respondents was 230, including all directors, councilors, and senior doctors. Agreement with the definition of primary frozen shoulder was 67%, the classification of primary or secondary frozen shoulder was 53%, and the 3 divisions of secondary frozen shoulder was 53%. Diagnostic terms for the cases of shoulder stiffness with unknown etiology were as follows: frozen shoulder (31%), stiff shoulder (22%), periarthritis scapulohumeralis (16%), so called "Gojukata" in Japan, which means shoulder problems in their fifties (16%), idiopathic frozen shoulder (6%), primary frozen shoulder (4%), adhesive capsulitis (3%), others (2%).

Conclusion: The survey shows lower rates of agreement among the JSS members than the ASES members for the definition of primary frozen shoulder, the classification of primary and secondary frozen shoulder, and the divisions of secondary frozen shoulder. To avoid confusion between stiff shoulder and frozen shoulder, the committee agrees to the ISAKOS recommendation that the term "frozen shoulder" should be used exclusively for primary idiopathic stiff shoulder.