Barker Priscilla J, Freeman Ashley D, Urquhart Donna M, Anderson Colin R, Briggs Christopher A
Department of Anatomy & Cell Biology, The University of Melbourne, Parkville, Victoria 3010, Australia.
Clin Biomech (Bristol). 2010 Jul;25(6):505-9. doi: 10.1016/j.clinbiomech.2010.02.008. Epub 2010 Apr 1.
Transversus abdominis and its aponeurotic attachment to the lumbar transverse processes via the middle layer of lumbar fascia are of proposed clinical and biomechanical importance. Moderate traction on these structures (simulating submaximal contraction of transversus abdominis) is reported to influence segmental motion, but their tensile capacity is unknown and the effects of sudden, maximal traction on these attachments and the transverse processes are uncertain.
In 15 embalmed cadaver abdomens, the middle layer of lumbar fascia was isolated, gripped and rapid tension applied in either a lateral or posteroanterior direction (simulating forces that may produce avulsion and traumatic fractures). Peak forces prior to tissue failure were recorded and the gross effects of traction documented.
Lumbar transverse process fractures were produced in all specimens; by transverse traction in 50% of tests and posteroanterior force in 80%. In the remainder the middle layer of lumbar fascia was torn. Mean transverse and posteroanterior peak forces reached in the middle layer of lumbar fascia prior to failure were 82 N (range 20-190 N) and 47 N (range 25-70 N), respectively.
The middle layer of lumbar fascia can transmit substantial tensile forces to lumbar vertebrae, capable of transverse process fracture under experimental conditions. Tensile capacity is likely to be even greater in-vivo. This suggests transversus abdominis and the middle layer of lumbar fascia can strongly influence vertebral motion, should be incorporated in biomechanical models of the spine and considered as potential contributors to transverse process fractures by avulsion.
腹横肌及其通过腰筋膜中层与腰椎横突的腱膜附着在临床和生物力学方面具有重要意义。据报道，对这些结构施加适度牵引（模拟腹横肌的次最大收缩）会影响节段性运动，但其拉伸能力未知，且突然的最大牵引对这些附着点和横突的影响尚不确定。
在15具防腐处理的尸体腹部中，分离出腰筋膜中层，进行夹持并在外侧或后前方向施加快速张力（模拟可能导致撕脱和创伤性骨折的力）。记录组织破坏前的峰值力，并记录牵引的总体效果。
所有标本均出现腰椎横突骨折；50%的测试中由横向牵引导致，80%由后前向力导致。其余情况下腰筋膜中层撕裂。腰筋膜中层在破坏前达到的平均横向和后前向峰值力分别为82 N（范围20 - 190 N）和47 N（范围25 - 70 N）。
腰筋膜中层能够将相当大的拉力传递至腰椎，在实验条件下可导致横突骨折。其拉伸能力在体内可能更大。这表明腹横肌和腰筋膜中层可强烈影响椎体运动，应纳入脊柱生物力学模型，并被视为撕脱性横突骨折的潜在原因。
