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A Novel Technique to Assess Distal Radioulnar Joint Stability Using Increasing Torque
Klara Nilsson1, Peter Hallberg2, Erik Tesselaar1,3
1Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.
Journal of Wrist Surgery
|August 13, 2019
Summary
A new device measures distal radioulnar joint (DRUJ) laxity during computed tomography (CT) scans, aiding in the diagnosis of triangular fibrocartilage complex (TFCC) injuries by assessing torque resistance.
Area of Science:
- Orthopedics
- Radiology
- Biomechanics
Background:
- Assessing distal radioulnar joint (DRUJ) laxity in triangular fibrocartilage complex (TFCC) injuries is challenging with current computed tomography (CT) methods.
- Previous studies lacked effective techniques for dynamic DRUJ laxity evaluation.
Purpose of the Study:
- To develop and validate a novel servomotor-driven device for quantifying DRUJ laxity.
- To establish reference values for DRUJ range of motion (ROM) and torque tolerance in healthy individuals.
- To assess the device's utility in diagnosing TFCC injuries via 4D CT.
Main Methods:
- A custom servomotor device was integrated with 4D CT to apply controlled torque to the DRUJ.
- 110 healthy participants underwent testing to establish normative ROM and torque data.
- The device was tested on 5 patients with suspected TFCC injuries.
Main Results:
- Reference charts for DRUJ ROM and torque were created, showing variations by gender, age, and hand dominance.
- Patients with suspected TFCC injuries demonstrated significantly reduced torque tolerance in pronation and supination compared to controls.
- Real-time 4D CT imaging revealed clear DRUJ laxity in injured patients, with an average 74% decrease in strength.
Conclusions:
- The developed device provides clinically applicable reference values for assessing DRUJ torque strength and laxity.
- Integrating the device with CT allows for radiographic evaluation of instability under increasing torque.
- This technology can improve the diagnosis of ligamentous TFCC injuries.
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