For example, of the 105 participants, only 27 (26%) had positive provocative tests and arthroscopies for SL ligament injuries, 35 (33%) had positive provocative tests and arthroscopies for TFCC injuries, 17 (17%) had positive provocative tests and arthroscopies for lunate cartilage damage, 9 (9%) had positive provocative tests and arthroscopies for DRUJ injuries, 1 (1%) had positive provocative tests and arthroscopies for learn more LT ligament injuries, and 2 (2%) had positive provocative tests and arthroscopies for arcuate injuries. Most tests appeared

to have little or no diagnostic value. Possible exceptions were positive findings from the SS test (+ve LR 2.88, 95% CI 1.68 to 4.92) and the MC test (+ve LR 2.67, 95% CI 0.83 to 8.60) and negative findings from the SS PD98059 test (–ve LR 0.28, CI 0.15 to 0.55) and the DRUJ test (–ve LR 0.3, CI 0.11 to 0.86), all of which were mildly useful. There were a number of incidental arthroscopic findings. Arthroscopic findings in addition to ligament injuries and lunate cartilage damage included synovitis (66, 63%), ganglions (17, 16%), and cartilage damage excluding the lunate (24, 23%). Table 2 cross-tabulates findings of MRI and arthroscopy. Positive MRI findings for SL ligament injuries (LR 4.17, 95% CI 1.54 to 11.30), TFCC injuries (LR 5.56, 95% CI 1.92 to 16.10), and lunate cartilage damage (LR 3.67, 95% CI

1.84 to 7.32) were of mild to moderate diagnostic usefulness. Negative MRI findings for SL ligament injuries (0.32, 95% CI 0.16 to 0.65), TFCC injuries (0.15, 95% CI 0.06 to 0.37), and lunate cartilage damage (0.33, 95% CI 0.14 to 0.78) were likewise of mild to moderate diagnostic

usefulness. The usefulness of both provocative tests and MRI for diagnosing Ribonucleotide reductase ligament injuries is summarised in Table 3 according to a recommended interpretation of positive and negative LRs (Portney and Watkins, 2009). The incremental diagnostic value of adding MRI to provocative tests was statistically significant for TFCC injuries and lunate cartilage damage, as shown in Table 4 (p < 0.001). An additional 13% of participants were correctly diagnosed as having or not having TFCC injuries with MRI over and above those correctly diagnosed with provocative tests alone. That is, for every eight scans there was one more correct diagnosis of the presence or absence of TFCC injury (ie, the NNS was eight). The NNS for lunate cartilage lesions was 13. MRI did not significantly improve diagnostic accuracy of any other ligament injury. MRI provided little incremental diagnostic accuracy because 72% to 95% of participants were diagnosed correctly by the provocative tests alone. This was partly because a large proportion of participants who went on to MRI did not have ligament injuries ( Table 2). Information about the accuracy of provocative tests for diagnosing wrist ligament injuries is important for clinicians.