Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, Minnesota, USA.
J Orthop Res. 2012 Mar;30(3):443-7. doi: 10.1002/jor.21547. Epub 2011 Sep 2.
The subsynovial connective tissue (SSCT) in the carpal tunnel may play a role in the etiology of carpal tunnel syndrome (CTS), yet the material properties of the SSCT remain unclear. Thus, we investigated the mechanical response of the SSCT in a rabbit model. Twenty-four rabbit cadaver paws were used for mechanical testing; two paws were used for scanning electron microscopy (SEM) imaging. After testing normal tendon excursion, the divided third digit flexor digitorum superficialis (FDS) tendon was pulled to displacements of 2, 3.5, 5, or 8 mm, maintained at that position until force decay, and then the process was repeated. Normal excursion of the FDS averaged 4.8 mm. The ratio of the second peak force to the first peak force in the 2 mm group was 0.98 (SD = 0.16), which was significantly higher than the other groups (3.5 mm: 0.74, 5 mm, 0.63, and 8 mm: 0.59; p < 0.05). SEM showed ruptured fibrils in the displaced specimen. The declining force ratio with displacements >2 mm suggests damage to the SSCT within the physiological tendon excursion. These data may be useful in understanding SSCT mechanics in CTS, which is associated with SSCT fibrosis.
腕管滑膜下结缔组织（SSCT）可能在腕管综合征（CTS）的发病机制中起作用，但 SSCT 的力学性能仍不清楚。因此，我们在兔模型中研究了 SSCT 的力学响应。对 24 只兔尸爪进行力学测试；两只爪子用于扫描电子显微镜（SEM）成像。在测试正常肌腱运动后，将分离的第三指屈指浅肌（FDS）肌腱拉至 2、3.5、5 或 8mm 的位移处，保持在该位置直到力衰减，然后重复该过程。FDS 的正常运动平均为 4.8mm。2mm 组中第二峰值力与第一峰值力的比值为 0.98（SD=0.16），明显高于其他组（3.5mm：0.74、5mm：0.63、8mm：0.59；p<0.05）。SEM 显示在移位标本中出现断裂的纤维。在超过 2mm 的位移处下降的力比表明 SSCT 在生理肌腱运动范围内受到损伤。这些数据可能有助于理解与 SSCT 纤维化相关的 CTS 中的 SSCT 力学。
