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Issue: Vol. 562 No. 2 (2026)
Section: Các bài báo
DOI: 10.51298/vmj.v562i2.18789
Date Published: 06/09/2026
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How to Cite
Lê , N. Q., Hoàng , K. X., & Trần , T. X. C. (2026). BIOMECHANICAL STUDY OF DISTAL RADIOULNAR JOINT STABILITY IN ULNAR STYLOID FRACTURES. Vietnam Medical Journal, 562(2). https://doi.org/10.51298/vmj.v562i2.18789

BIOMECHANICAL STUDY OF DISTAL RADIOULNAR JOINT STABILITY IN ULNAR STYLOID FRACTURES

Ngọc Quyên Lê 1, , Khắc Xuân Hoàng 2, Trọng Xuân Cường Trần 1
1 University of Medicine and Pharmacy at Ho Chi Minh City
2 Carmel International Hospital

Main Article Content

Abstract

Objectives: To evaluate the stability of the distal radioulnar joint (DRUJ) in the context of ulnar styloid base fractures using a cadaveric model.


Methods: An experimental study was conducted on 22 fresh cadaveric wrist specimens. DRUJ displacement was measured at three stages: T0 – intact ulnar styloid; T1 – complete fracture of the ulnar styloid base with displacement > 2 mm; and T2 – reattachment of the ulnar styloid. Lateral, dorsal, and palmar displacements were recorded under traction forces ranging from 1 kg to 5 kg in neutral, maximum supination, and maximum pronation positions.


Results: Dorsal and palmar displacements of the DRUJ showed no significant differences across all three stages and three positions (p > 0.05). In contrast, lateral displacement increased significantly in all three positions after ulnar styloid osteotomy (T1 vs. T0: p = 0.0045 in neutral; p = 0.007 in supination; p = 0.008 in pronation). After reattachment (T2), lateral displacement tended to decrease compared to T1 but did not reach statistical significance (p > 0.05). Compared to T0, lateral displacement at T2 remained significantly elevated in neutral (p = 0.015) but was no longer significantly different in supination and pronation (p > 0.05).


Conclusions: The integrity of the deep limb of the radioulnar ligament (RUL) at the ulnar fovea is the primary determinant of dorsopalmar DRUJ stability. The superficial limb of the RUL contributes to DRUJ stability in the lateral direction. Therefore, an isolated ulnar styloid fracture should not be considered an absolute indication for surgical fixation provided that the deep limb of the RUL remains intact.

Keywords

distal radioulnar joint (DRUJ), radioulnar ligament (RUL), ulnar styloid process

Article Details

References

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