Extended and weightbearing wrist 3-T MRI using a novel harness and flexible 24-channel glove coil to evaluate carpal kinematics: a pilot study in 10 volunteers

Abstract

Background Wrist pain in the extended or extended weightbearing positions may be incompletely evaluated using standard magnetic resonance imaging (MRI) with standard rigid clamshell coils in the neutral position. Purpose To evaluate a flexible 24-channel glove coil and harness when imaging the wrist in neutral, dorsally extended, and weightbearing positions. Material and Methods Ten wrists in 10 asymptomatic volunteers (mean age = 29 years) were scanned. Participants underwent 3-T MRI using the harness and flexible glove coil, acquiring sagittal turbo spin echo (TSE) and half-Fourier acquisition single-shot turbo spin echo (HASTE) pulse sequences. Static TSE images were obtained in neutral, extended, and weightbearing positions using proton density parameters and independently evaluated by two radiologists for: dorsal radiocarpal ligament thickness; radiocapitate, radiolunate, and capitatolunate angles; palmar translation of the lunate on the radius; angulation of the extensor tendons; and distance from the distal extensor retinaculum to Lister's tubercle. Cine HASTE images were dynamically acquired between neutral-maximum extension to measure the radiocapitate angle. Results Good reader agreement was observed (r > 0.73) for all measurements except palmar translation in the neutral position (r = 0.27). Significant increases in dorsal radiocarpal ligament thickness; radiocapitate, radiolunate and capitolunate angulation; and extensor tendon angulation were observed between the neutral and extended positions ( P < 0.001). A further significant increase in these metrics between extended and weightbearing positions was also seen ( P < 0.01). Conclusion Significant increases in dorsal radiocarpal ligament thickness, articular and tendon angulations occur during wrist extension, that further increase with dorsal weightbearing.