León-López M M, García-Elías M, Salvà-Coll G, Llusá-Perez M, Lluch-Bergadà A
Departamento de Traumatología, Hospital Can Misses, Ibiza, España.
Institut Kaplan, Barcelona, España.
Rev Esp Cir Ortop Traumatol. 2014 Jan-Feb;58(1):11-8. doi: 10.1016/j.recot.2013.10.002. Epub 2013 Dec 17.
As long as the neuromuscular stabilizers are intact, a lesion of the scapholunate ligament may or may not progress to a carpal instability. The mechanisms by which the muscles compensate this defect are not very well known. We designed an experimental study with the aim of clarifying these mechanisms.
Using 10 fresh wrists, with no pre-existing lesions, we studied the movements of the scaphoid, triquetrum and capitate produced by the isometrical loading of the muscles which move the wrist, each of them isolated or combined, before and after cutting off the scapholunate ligaments. To do this, we placed sensors in each of these bones and used the Fastrack system to record these movements.
The simultaneous loading of the muscles of the wrist produce rotational movements in flexion and supination of the proximal carpal row. After cutting off the scapholunate ligaments, the scaphoid rotates in pronation and flexion, while the triquetrum rotates in pronation and extension. In this situation of a scapholunate lesion, the muscles that worsen the carpal dexasation are the extensor carpi ulnaris and flexor carpi ulnaris. On the other hand, the isolated loading of the radial muscles reduce the scapholunate diastasis, thus improving the carpal alignment.
In dynamic scapholunate instabilities, isometric contraction of the ulnar carpal muscles must be avoided, as it promotes the scapholunate diastasis. The rest of the muscles have the opposite effect, stabilizing the carpus when primary stabilizers have failed.
只要神经肌肉稳定器完好无损，舟月韧带损伤可能会也可能不会发展为腕关节不稳定。肌肉补偿这种缺陷的机制尚不清楚。我们设计了一项实验研究，旨在阐明这些机制。
使用10个无既往损伤的新鲜腕关节，研究在切断舟月韧带前后，使腕关节运动的肌肉等长负荷单独或联合作用时，舟骨、三角骨和头状骨的运动。为此，我们在这些骨头中放置传感器，并使用Fastrack系统记录这些运动。
腕关节肌肉同时负荷会使近端腕骨排产生屈曲和旋前的旋转运动。切断舟月韧带后，舟骨在旋前和屈曲时旋转，而三角骨在旋前和伸展时旋转。在舟月韧带损伤的这种情况下，使腕关节脱位加重的肌肉是尺侧腕伸肌和尺侧腕屈肌。另一方面，桡侧肌肉单独负荷会减少舟月间隙，从而改善腕关节排列。
在动态舟月不稳定中，必须避免尺侧腕部肌肉的等长收缩，因为它会促进舟月间隙增宽。当主要稳定器失效时，其余肌肉具有相反的作用，可稳定腕关节。
