Imaging the Ligaments and Tendons of the Wrist

Peripheral tear of the triangular fibrocartilage complex: diagnostic accuracy of magnetic resonance imaging and diagnostic performance of the primary and secondary signs

OBJECTIVE

This study is to assess the diagnostic performance of magnetic resonance imaging (MRI) findings for type 1B triangular fibrocartilage complex (TFCC) tear of the wrist.

MATERIALS AND METHODS

This study retrospectively enrolled 78 patients to examine the diagnostic performance of preoperative MRI examinations in patients with type 1B TFCC tears. Thirty-nine participants had confirmed type 1B TFCC tear. The control group included 39 patients who were randomly selected from 1157 patients who underwent MRI for wrist pain. Both groups underwent a review of 19 MRI findings by two independent radiologists, and the correlation between each diagnostic finding and type 1B TFCC tear was assessed using the chi-squared test. The 19 MRI findings comprised eight primary signs of abnormalities in the distal or proximal lamina, in conjunction with 11 secondary signs suggestive of abnormalities in the surrounding structures.

RESULTS

The TFCC tear group demonstrated a significantly higher incidence of two primary MRI signs, i.e., fiber discontinuity and signal alteration in the distal lamina, as observed by both readers (R1, 74.4% vs. 38.5%, p = 0.003, and 87.2% vs. 43.6%, p < 0.001; R2, 74.4% vs. 35.9%, p = 0.001, and 87.2% vs. 53.8%, p < 0.003, respectively). Reader 2 identified a higher prevalence of two additional primary MRI signs: fiber discontinuity and signal alteration in the proximal lamina (all p < 0.05). None of the 11 secondary MRI signs demonstrated statistically significant associations with type 1B TFCC.

CONCLUSION

MRI manifestations of fiber discontinuity and signal alteration in the distal lamina may provide predictive markers for type 1B TFCC wrist tear.

Visualization of wrist ligaments with 3D and 2D magnetic resonance imaging at 3 Tesla

BACKGROUND

Wrist ligaments are challenging to visualize using magnetic resonance imaging (MRI). Injuries involving the scapholunate ligament (SLL), the lunotriquetral ligament (LTL), and the triangular fibrocartilage complex (TFCC) are common and difficult to diagnose, often requiring diagnostic arthroscopy.

PURPOSE

To compare the visualization of wrist ligaments on a three-dimensional (3D) sequence with two-dimensional (2D) sequences on 3-T MRI.

MATERIAL AND METHODS

Eighteen healthy volunteers were examined with a 3D SPACE (sampling perfection with application optimized contrasts using different flip angle evolution) sequence and 2D coronal, axial, and sagittal proton density-weighted (PD) sequences. Four musculoskeletal radiologists graded the anatomical visibility of the SLL, LTL, TFCC, and the image quality, using five grades in a visual grading characteristics (VGC) evaluation. After Bonferroni correction, a P value ≤0.005 was considered statistically significant.

RESULTS

The 3D images were graded significantly better than the 2D images in the visualization of the dorsal and palmar parts of the SLL and the LTL. Regarding the TFCC, the 3D images were graded significantly better for visualization of the foveal attachment. 2D imaging was not found significantly superior to 3D imaging in any aspect.

CONCLUSION

The 3D SPACE sequence was scored as superior to the 2D sequences at 3 T in the assessment of the SLL, the LTL, and the foveal attachment of the TFCC. Thus, 3D SPACE can replace 2D PD sequences when these ligaments need to be assessed.

[Establishing a standardized diagnostic Procedure for sonographic Imaging and Evaluation of the scapholunate Ligament]

BACKGROUND

Ultrasound has not yet been established in the diagnostic workup of scapholunate ligament lesions. We aimed to develop a standardised examination procedure to visualise and evaluate the SL ligament.

PATIENTS AND METHODS

Forty patients (70 hands) were examined prospectively with ultrasonography and the results were compared with arthroscopy and MRI findings. We studied the visibility of the SL ligament and the SL distance on side-to-side comparison and performed a method comparison between MRI/arthroscopy and ultrasound, testing for distinction and accordance. Cut-off values for the SL distance indicating a lesion were determined and all parameters were used for developing a score.

RESULTS

An intact ligament appears as a hyperechogenic, fibrillary structure and shows discontinuity or a hypoechogenic space when injured. An intact ligament was visible dorsally in 89.6 % and palmarly in 83.3 %. The SL distance for an intact ligament was 5/2/5.1 mm for the dorsal/middle/palmar aspect (range 3.2-6.7/0.9-4/3.1-7.8 mm) and 6.4/3/6.3 mm (range 5-9.4/2-6.2/4-9.3 mm) for a lesion. The difference between the right and left hand with an intact ligament was a maximum of 2.1/1.1/1.8 mm, an average of 0.4/0.2/0.2 mm; in case of an injury, the maximum difference was 1.2/0.9/1.1 mm. Distance values for radial and ulnar deviation were physiological but partly unpredictable. The cut-off values determined for a lesion are 5.05 mm for the dorsal aspect (sensitivity/specificity 0.95/0.60), 1.95 mm for the middle (1/0.62) and 6.15 mm for the palmar aspect (0.55/0.85). The created sonographic SL ligament score has a high AUC (area under the curve) of 0.93, a sensitivity of 85 % and a specificity of 90 %.

CONCLUSION

The parameters, especially when combined to a score, allow to state whether the SL ligament is intact or not. Ultrasound can, therefore, be recommended as a diagnostic and screening method for an SL ligament lesion und should be used as a routine tool. The criteria must be checked from a perspective with high case numbers.

Overuse wrist injuries in adolescent platform and springboard divers

To investigate overuse wrist injuries in adolescent divers using magnetic resonance imaging (MRI). The bilateral wrists (76 wrists) of 38 professional divers were examined by MRI; 42 wrists with pain were placed in the symptomatic group, and 34 wrists without pain were placed in the asymptomatic group. Two experienced radiologists assessed the wrist injuries. Chi‑square test was used to compare the difference in injuries between the two groups. Subchondral osteosclerosis was observed in 47.62% of symptomatic wrists and 52.94% of asymptomatic wrists. Distal radial epiphyseal plate injury was detected in 42.86% of symptomatic wrists and 11.76% of asymptomatic wrists. Triangular fibrocartilage complex injury was observed in 19.04% of symptomatic wrists and 8.82% of asymptomatic wrists. Bursae around the wrist were observed in 21.42% of symptomatic wrists and 17.64% of asymptomatic wrists. The incidence of distal radial epiphyseal plate injury was higher in the symptomatic group than in the asymptomatic group (P = 0.007), however, other injuries were not statistically different between the two groups (P > 0.05). This study demonstrated that adolescent divers had various wrist injuries, and distal radial epiphyseal plate injury was more common in the symptomatic wrist; these injuries show no specific clinical symptoms and are easily overlooked.

Visualization of wrist anatomy-a comparison between 7T and 3T MRI

OBJECTIVE

Injuries to the wrist are, due to its small size and complex anatomical structures, difficult to assess by MR, and surgical interventions such as diagnostic arthroscopy are often necessary. Therefore, improved visualization using non-invasive methods could be of clinical value. As a first step of improvement, the purpose of this study was to evaluate visualization of anatomical structures at 7T compared with 3T MR.

METHODS

Eighteen healthy volunteers (three males and three females from each age decade between 20 and 49 years) were examined with 7T and 3T MR. Four musculoskeletal radiologists graded 2D and 3D images on a five-level grading scale for visibility of ligaments, cartilage, nerves, trabecular bone, and tendons, as well as overall image quality (i.e., edge sharpness, perceived tissue contrast, and presence of artefacts). Statistical analysis was done using a visual grading characteristics (VGC) analysis.

RESULTS

Visibility of cartilage, trabecular bone, tendons, nerves, and ligaments was graded significantly higher at 7T with an area under the curve (AUC_VGC) of 0.62-0.88 (95% confidence interval [CI] 0.50-0.97, p = < 0.0001-0.03) using either 2D or 3D imaging. Imaging with 3T was not graded as superior to 7T for any structure. Image quality was also significantly superior at 7T, except for artefacts, where no significant differences were found.

CONCLUSIONS

Tendons, trabecular bone, nerves, and ligaments were all significantly better visualized at 7T compared to 3T.

KEY POINTS

• MRI of the wrist at 7T with a commercially available wrist coil is feasible at similar acquisition times as for 3T MRI. • The current study showed 7T to be superior to 3T in the visualization of anatomical structures of the wrist, including ligaments, tendons, nerves, and trabecular bone. • Image quality was significantly superior at 7T, except for artefacts, where no significant differences were found.

The Acutely Injured Wrist

Wrist traumas are a frequent clinical emergency for which instrumental imaging assessment is required. The purpose of this article is to review the role of imaging assessment of traumatic wrist injuries, with particular reference to fractures and associated lesions.

MR imaging of the traumatic triangular fibrocartilaginous complex tear

Triangular fibrocartilage complex is a major stabilizer of the distal radioulnar joint (DRUJ). However, triangular fibrocartilage complex (TFCC) tear is difficult to be diagnosed on MRI for its intrinsic small and thin structure with complex anatomy. The purpose of this article is to review the anatomy of TFCC, state of art MRI imaging technique, normal appearance and features of tear on MRI according to the Palmar's classification. Atypical tear and limitations of MRI in diagnosis of TFCC tear are also discussed.

Dynamic high-resolution ultrasound of intrinsic and extrinsic ligaments of the wrist: How to make it simple

Wrist ligaments are crucial structures for the maintenance of carpal stability. They are classified into extrinsic ligaments, connecting the carpus with the forearm bones or distal radioulnar ligaments, and intrinsic ligaments, entirely situated within the carpus. Lesions of intrinsic and extrinsic ligaments of the wrist have been demonstrated to occur largely, mostly in patients with history of trauma and carpal instability, or rheumatoid arthritis. Ultrasound allows for rapid, cost-effective, non-invasive and dynamic evaluation of the wrist, and may represent a valuable diagnostic tool. Although promising results have been published, ultrasound of wrist ligaments is not performed in routine clinical practice, maybe due to its technical feasibility regarded as quite complex. This review article aims to enlighten readers about the normal sonographic appearance of intrinsic and extrinsic carpal ligaments, and describe a systematic approach for their sonographic assessment with detailed anatomic landmarks, dynamic manoeuvres and scanning technique.

Perilunate dislocations and fracture dislocations

Perilunate dislocations and fracture dislocations are high-energy injuries that can result in pain, stiffness, weakness, or disability if inappropriately treated. Prompt recognition and surgical treatment with anatomic reduction of carpal malalignment improve the likelihood of optimal, long-term clinical success and patient satisfaction. The progressive development of radiographic evidence of arthrosis is common but has not been shown to consistently correlate with worse patient function and outcomes.

Current perspectives on the advantages of 3-T MR imaging of the wrist

The use of 3-T magnetic resonance (MR) imaging systems with improved coil designs and high-resolution MR imaging sequences allows visualization of the musculoskeletal anatomy in exquisite detail and accurate characterization of abnormalities both in soft tissues and in bone. Current high-field-strength MR systems offer particular advantages for diagnostic imaging of the small joints of the extremities, especially the wrists, where multiple overlapping soft-tissue structures may be visually inseparable at lower field strengths because of limited contrast resolution. Diagnostic accuracy obtained with 3-T MR imaging of the wrist performed with an acquisition protocol that includes three-dimensional and proton density-weighted imaging sequences is nearly commensurate with that obtained with MR arthrography. Abnormalities of the ligaments, tendons, cartilage, nerves, blood vessels, and bone are clearly depicted, allowing accurate characterization of perforations, tears, and fractures, as well as various soft-tissue and intraosseous lesions (eg, ganglion cysts), vascular malformations, aneurysms, and neuropathies.