Extensor carpi ulnaris tendinopathy, tenosynovitis, and tendon rupture can be evaluated with MRI or US [43]. However, dynamic instability may be missed on MRI, unless sequences are performed in pronation and supination [44]. MR Arthrography Wrist At 1.5T, MR arthrography has greater sensitivity compared with conventional MRI [45,46]. Both MRI and MR arthrography have poor to moderate sensitivity for partial ligament tears [47,48]. When only complete tears are considered, MRI and MR arthrography may be equivalent [33]. The accuracy of MR arthrography for extrinsic ligament assessment is unknown [37]. For tears of the dorsal band of the scapholunate ligament, US sensitivity varies from 46% to 100% and specificity from 92% to 100% [50-52]. For the dorsal band of the lunotriquetral ligament, US sensitivity ranges from 25% to 50% and specificity from 90% to 100% [52,53]. US visualization of lunotriquetral ligament (particularly the structurally important volar band) is limited [49]. US can show dynamic subluxation of the extensor carpi ulnaris tendon during forced supination [44]. Bone Scan Wrist Bone scan is not indicated in this clinical setting. Variant 4: Initial radiographs showing distal radioulnar joint or carpal malalignment in the absence of fracture. Next imaging study. CT Wrist CT is the modality of choice for evaluating distal radioulnar joint stability [54]. The CT protocol should include imaging of both wrists in maximal pronation, neutral position, and maximal supination. CT examination with coronal, sagittal, and 3-D reformed images help demonstrate the extent of injury and help in treatment planning, particularly in cases of chronic perilunate dislocation [55]. CT Arthrography Wrist Distal radioulnar joint instability and traumatic triangular fibrocartilage injuries can be evaluated with CT arthrography [56,57].
Acute Hand and Wrist Trauma. Extensor carpi ulnaris tendinopathy, tenosynovitis, and tendon rupture can be evaluated with MRI or US [43]. However, dynamic instability may be missed on MRI, unless sequences are performed in pronation and supination [44]. MR Arthrography Wrist At 1.5T, MR arthrography has greater sensitivity compared with conventional MRI [45,46]. Both MRI and MR arthrography have poor to moderate sensitivity for partial ligament tears [47,48]. When only complete tears are considered, MRI and MR arthrography may be equivalent [33]. The accuracy of MR arthrography for extrinsic ligament assessment is unknown [37]. For tears of the dorsal band of the scapholunate ligament, US sensitivity varies from 46% to 100% and specificity from 92% to 100% [50-52]. For the dorsal band of the lunotriquetral ligament, US sensitivity ranges from 25% to 50% and specificity from 90% to 100% [52,53]. US visualization of lunotriquetral ligament (particularly the structurally important volar band) is limited [49]. US can show dynamic subluxation of the extensor carpi ulnaris tendon during forced supination [44]. Bone Scan Wrist Bone scan is not indicated in this clinical setting. Variant 4: Initial radiographs showing distal radioulnar joint or carpal malalignment in the absence of fracture. Next imaging study. CT Wrist CT is the modality of choice for evaluating distal radioulnar joint stability [54]. The CT protocol should include imaging of both wrists in maximal pronation, neutral position, and maximal supination. CT examination with coronal, sagittal, and 3-D reformed images help demonstrate the extent of injury and help in treatment planning, particularly in cases of chronic perilunate dislocation [55]. CT Arthrography Wrist Distal radioulnar joint instability and traumatic triangular fibrocartilage injuries can be evaluated with CT arthrography [56,57].