Forearm Interosseous Membrane Maintains the Stability of Proximal Radioulnar Joint

Abstract

Objective: To evaluate the effect of the proximal and central bundles of the interosseous membrane on the stability of proximal radioulnar joint.

Methods: Twenty fresh samples of human forearm provided by the anatomy room of the Department of Human Anatomy of Nanjing Medical University were included in this study. They were used to explore the effect of proximal interosseous membrane bundle on the stability of proximal radioulnar joint. The proximal bundle was reconstructed along the original attachment point. The reconstructions of central bundle were divided into the reconstruction of original attachment point on radius-midpoint of the ulnar original attachment point (reconstruction A) and original attachment point reconstruction (reconstruction B). The loads of the proximal radioulnar joint in different positions were measured. The load of the proximal radioulnar joint was analyzed in neutral, pronation, and supination positions.

Results: After resection of proximal and central fascicles, the loads of proximal radioulnar joint in neutral, pronation, and supination positions were significantly lower than those before resection (P < 0.05). After reconstruction, the loads of proximal radioulnar joint in neutral and supination positions were higher than those after resection (P < 0.05). After reconstruction, the loads of proximal radioulnar joint in neutral and supination positions were higher than those after resection (P < 0.05), and that after reconstruction B in pronation position was higher than that after resection (P < 0.05), while there was no significant difference between reconstruction A and after resection (P > 0.05). In supination position, the load of reconstruction B was higher than that of reconstruction A (P < 0.05). After reconstruction of the proximal and central bundles, the proximal radioulnar joint could not reached the same load as it could before resection (P < 0.05).

Conclusion: The stability of proximal radioulnar joint is affected by central bundle and proximal bundle. Reconstruction can increase the stability of proximal radioulnar joint.

Keywords: Biomechanics; Central bundle; Proximal bundle; Proximal radioulnar joint.

Fig. 1

The imagines of the patient. (A) The forearm muscles were removed, leaving only forearm interosseous membrane, annular ligament, ulna, radius, and wrist. (B) The proximal bundle was reconstructed along the original attachment point. (C) The method of reconstruction A. (D) The method of reconstruction B.