Real-time MRI may improve the functional diagnosis of SLL insufficiency: study

Clinical-standard MRI is the imaging modality of choice for the wrist, yet limited to static evaluation, thereby potentially missing dynamic instability patterns.

Lena Marie Wilms et al aimed to investigate the clinical benefit of (dynamic) real-time MRI, complemented by automatic analysis, in patients with complete or partial scapholunate ligament (SLL) tears. The study has been published in ‘Skeletal Radiology’ journal.

Both wrists of ten patients (male: 8; female: 2; mean age: 41.2 ± 18.1 years, age range: 24 – 66 years) with unilateral SLL tears (six partial, four complete tears) as diagnosed by clinical-standard MRI were imaged during continuous active radioulnar motion using a 1.5-T MRI scanner (MAGNETOM Avantoft, Siemens Healthineers, Erlangen, Germany) in combination with a custom-made motion device.

Following automatic segmentation of the wrist, the scapholunate and lunotriquetral joint widths were analyzed across the entire range of motion (ROM). Mixed-effects model analysis of variance (ANOVA) followed by Tukey’s posthoc test and two-way ANOVA were used for statistical analysis.

Key findings of the study were:

• In healthy controls, the scapholunate joint width remained stable at around 2 mm over the entire ROM.

• With the increasing extent of SLL tear, the scapholunate joint widths in injured wrists were significantly larger over the entire ROM compared to those of the contralateral healthy wrists (p<0.001).

• Differences between partial and complete tears were most pronounced at 5°–15° ulnar abduction (p <0.001). Motion patterns and trajectories were altered.

• Complete SLL deficiency resulted in complex alterations of the lunotriquetral joint widths.

The authors concluded - “Real-time MRI may improve the functional diagnosis of SLL insufficiency and aid therapeutic decision-making by revealing dynamic forms of dissociative instability within the proximal carpus. Static MRI best differentiates SLL-injured wrists at 5°–15° of ulnar abduction.

Further reading:

Dynamic assessment of scapholunate ligament status by real time magnetic resonance imaging: an exploratory clinical study Lena Marie Wilms et al Skeletal Radiology (2024) 53:791–800 https://doi.org/10.1007/s00256-023-04466-6