ABSTRACT
STUDY DESIGN: Clinical measurement. INTRODUCTION: Common provocative maneuvers to differentiate thumb carpometacarpal (CMC) osteoarthritis from other sources of pain are the grind, metacarpal (MC) flexion, and MC extension tests. A maneuver known as the pressure-shear test is described here. PURPOSE OF THE STUDY: To compare the diagnostic value of the grind, metacarpal flexion, metacarpal extension, and pressure-shear tests for CMC osteoarthritis of the thumb. METHODS: The diagnostic accuracy of each test was compared in 127 thumbs from 104 patients. Sensitivity, specificity, and predictive values of each test were calculated. In a secondary analysis, polychoric correlation coefficients were used to assess the correlation of each test with severity defined by Eaton-Littler stage. RESULTS: The overall diagnostic accuracy of the thumb MC grind, pressure-shear, flexion, and extension tests were 70%, 98%, 47%, and 55%, respectively. The sensitivities were 64%, 99%, 36%, and 46%, respectively, and specificities were 100%, 95%, 100%, and 100%, respectively. For the diagnosis of Thumb CMC arthritis, the MC pressure-shear test was superior overall in terms of overall diagnostic accuracy and sensitivity, while having comparable specificity to the other maneuvers. CONCLUSION: The pressure-shear test was found to be superior to the commonly used grind maneuver and the provocative maneuvers of MC flexion and extension tests to confirm diagnosis of CMC osteoarthritis.
