Reliability and Validity Analysis of the Distal Radioulnar Joint Ballottement Test

Purpose Triangular fi brocartilage complex injuries can cause distal radioulnar joint (DRUJ) instability, which can be evaluated clinically with the DRUJ ballottement test. However, the reliability and validity of the test are unclear. This study aimed to analyze the reliability and validity of the test using a tracking device on healthy participants and patients with triangular fi brocartilage complex injuries. Methods In this cross-sectional study, three orthopedic hand surgeons performed the DRUJ ballottement test using a technique of holding the carpal bones to the radius on 25 healthy participants (50 hands; 10 men and 15 women; mean age, 33 years; range, 20-51- 51 years) and eight patients with triangular fi brocartilage complex injuries (16 hands; six men and two women; mean age, 43 years; range, 27-59- 59 years). We used a three-dimensional electromagnetic tracking device to quantify the movement of the DRUJ and verify the reliability and validity of the test. Results The intrarater and interrater intraclass correlation coefficients fi cients for DRUJ movement were 0.77 and 0.61, respectively, and the kappa coefficient fi cient for grading of DRUJ instability was 0.79. The correlation coefficient fi cient between DRUJ movement measured using the tracking device and instability judged clinically was 0.77. A comparison of healthy participants and the patients showed significantly fi cantly greater DRUJ movement in the patients. Conclusions The test showed substantial intrarater and interrater reliability for assessing DRUJ movement and instability. The significant fi cant positive correlation between DRUJ movement and instability indicates the concurrent validity of the test. Moreover, the test showed discriminative validity in identifying mild or moderate DRUJ instability. Clinical relevance The DRUJ ballottement test using the holding technique has a relatively high diagnostic accuracy and can be used to assess DRUJ instability. (J Hand Surg Am. 2024;49(1):15-22.- 22. Copyright (c) 2024 by the American Society for Surgery of the Hand. All rights reserved.)