Lee Steve K, Park Joseph, Baskies Michael, Forman Rachel, Yildirim Gokce, Walker Peter
Minimally Invasive Surgery Laboratory and the Division of Hand Surgery, Department of Orthopaedic Surgery, NYU Hospital for Joint Diseases, New York University School of Medicine, New York, NY 10003, USA.
J Hand Surg Am. 2010 Feb;35(2):245-51. doi: 10.1016/j.jhsa.2009.10.031. Epub 2010 Jan 8.
To directly measure strain changes in the scapholunate ligament via magnetic resonance imaging (MRI) when axially loading the wrist in the neutral and extended positions.
Six asymptomatic male volunteers without known history of previous wrist injury were enrolled in this MRI-based study. Each subject underwent 3 MRI scans in a 3T scanner: in resting neutral position, in neutral with axial load applied, and in extension with axial load applied. Axial load was applied via extension of an elastic band with known force/elongation curve. We analyzed images and converted them to 3-dimensional stereolithographs. Attachment points of the palmar, proximal, and dorsal sections of the scapholunate interosseus ligament (SLIL) were identified. The lengths of the resulting vectors were recorded for each position. Strain, defined as change in length divided by original length, was calculated for the axially loaded neutral and extended wrists. We used the Bonferroni adjusted multiple comparisons from an analysis of variance model, with statistical significance defined as p < .05.
Strains were significantly greater in the palmar (p = .02) and proximal (p = .01) subregions of the SLIL in loaded extension versus loaded neutral positions. In contrast, the strain on the dorsal component in extension was not statistically greater than in the neutral position (p = .45). Axial load in neutral resulted in minimal strain of all 3 components of the SLIL complex, and these were not significantly different from each other (p > .99). With extension, the strains of the palmar (p = .03) and proximal (p = .006) regions were statistically greater than that of the dorsal component.
In extension, strain is greatest in the palmar and proximal portions of the intact SLIL. Axial load in neutral applies minimal strain to the SLIL complex. Avoiding axial loading in extension and encouraging loading in neutral position may allow for decreased injury and more effective healing of the scapholunate ligament.
通过磁共振成像（MRI）直接测量在中立位和伸展位轴向加载腕关节时舟月韧带的应变变化。
本基于MRI的研究纳入了6名无既往腕关节损伤史的无症状男性志愿者。每位受试者在3T扫描仪中接受3次MRI扫描：静息中立位、施加轴向负荷的中立位以及施加轴向负荷的伸展位。通过拉伸具有已知力/伸长曲线的弹性带来施加轴向负荷。我们分析图像并将其转换为三维立体光刻模型。确定舟月骨间韧带（SLIL）掌侧、近端和背侧部分的附着点。记录每个位置所得向量的长度。计算轴向加载的中立位和伸展位腕关节的应变，应变定义为长度变化除以原始长度。我们使用方差分析模型的Bonferroni校正多重比较，统计学显著性定义为p <.05。
与加载中立位相比，加载伸展位时SLIL的掌侧（p =.02）和近端（p =.01）子区域的应变显著更大。相比之下，伸展位时背侧部分的应变在统计学上并不大于中立位（p =.45）。中立位的轴向负荷导致SLIL复合体所有3个部分的应变最小，且它们之间无显著差异（p >.99）。在伸展位时，掌侧（p =.03）和近端（p =.006）区域的应变在统计学上大于背侧部分。
在伸展位时，完整SLIL的掌侧和近端部分应变最大。中立位的轴向负荷对SLIL复合体施加的应变最小。避免在伸展位轴向加载并鼓励在中立位加载可能有助于减少舟月韧带损伤并促进更有效的愈合。
