Smith Chris D, Masouros Spyridon D, Hill Adam M, Wallace Andrew L, Amis Andrew A, Bull Anthony M J
Department of Bioengineering, Imperial College London, London, England.
Arthroscopy. 2009 May;25(5):504-9. doi: 10.1016/j.arthro.2008.12.012. Epub 2009 Feb 26.
The aim of the study was to define the normalized compressive stiffness (modulus) of the glenoid labrum around its circumference and to characterize the difference in modulus between different areas.
Sixteen fresh-frozen cadaveric shoulders were harvested and dissected down to the glenoid labrum. Any specimens with significant degenerative changes were discarded, leaving 8 labra for testing. The labrum was divided into 8 segments, to allow comparison around its circumference. A uniform testing specimen was produced from each area by use of a microtome. Each specimen measured 3 x 1 mm in cross section and was 6 mm in length. Indentation testing was conducted in a controlled environment of 100% humidity at 37 degrees C +/- 1 degrees C.
We obtained 52 test samples from 8 labra. The mean modulus of the glenoid labrum was 69.7 megapascal (standard deviation, 36.2 megapascal). The anterosuperior portion of the labrum had a higher modulus than the posteroinferior portion (P = .0075).
This study has shown that the human glenoid labrum's compressive behavior varies around its circumference. The greater modulus of the anterosuperior portion of the labrum supports the theory that this area is anatomically different from the rest of the labrum and resists compressive loads.
These results may explain why the common type of SLAP lesions seen show failure at the interface between the labrum and the glenoid rather than within the substance of the labrum itself.
本研究旨在确定肩胛盂唇在其圆周周围的归一化压缩刚度（模量），并描述不同区域之间模量的差异。
获取16个新鲜冷冻的尸体肩部并解剖至肩胛盂唇。丢弃任何有明显退行性改变的标本，留下8个盂唇用于测试。将盂唇分为8个部分，以便在其圆周周围进行比较。使用切片机从每个区域制作均匀的测试标本。每个标本的横截面尺寸为3×1毫米，长度为6毫米。在37℃±1℃、湿度100%的受控环境中进行压痕测试。
我们从8个盂唇中获得了52个测试样本。肩胛盂唇的平均模量为69.7兆帕斯卡（标准差为36.2兆帕斯卡）。盂唇的前上部分比后下部分具有更高的模量（P = 0.0075）。
本研究表明，人类肩胛盂唇的压缩行为在其圆周周围有所不同。盂唇前上部分较大的模量支持了这一理论，即该区域在解剖结构上与盂唇的其他部分不同，并且能够抵抗压缩载荷。
这些结果可能解释了为什么常见类型的SLAP损伤表现为在盂唇与肩胛盂的界面处失效，而不是在盂唇本身的实质内。
