Hossain M, Nokes L D M
Ysbyty Gwynedd, Penrhosgarnedd Road, Bangor LL57 2PW, UK.
Med Hypotheses. 2005;65(2):278-81. doi: 10.1016/j.mehy.2005.02.035.
The objective of this work is to propose a biomechanical model of sacro-iliac joint dysfunction as a cause of low back pain. Sacro-iliac joint is known to be a source of low back pain. We also know that it is a very stable joint with little mobility. Surrounding lower limb and back muscles contribute a major part of this stability. Gait analysis studies have revealed an orderly sequence of muscle activation when we walk - that contributes to efficient stabilisation of the joint and effective weight transfer to the lower limb. Gluteus maximus fibres-lying almost perpendicular to the joint surfaces are ideally oriented for this purpose. Biceps femoris is another important muscle that can also influence joint stability by its proximal attachment to sacrotuberous ligament. Altered pattern of muscle recruitment has been observed in patients with low back pain. But we do not know the exact cause-effect relationship. Because of its position as a key linkage in transmission of weight from the upper limbs to the lower, poor joint stability could have major consequences on weight bearing. It is proposed that sacro-iliac joint dysfunction can result from malrecruitment of gluteus maximus motor units during weight bearing. This results in compensatory biceps over activation. The resulting soft tissue strain and joint instability may manifest itself in low back pain. If our hypothesis holds true, it may have positive implications for patients with sacro-iliac joint dysfunction - who could be offered a definite diagnosis and targeted physiotherapy. It may be possible to identify patients early in a primary care setting and offer direct physio referral. They could benefit from exercises to improve strengthening and recruitment of the affected muscles.
这项工作的目的是提出一种将骶髂关节功能障碍作为下腰痛病因的生物力学模型。已知骶髂关节是下腰痛的一个源头。我们也知道它是一个非常稳定、活动度很小的关节。下肢和背部周围的肌肉对这种稳定性起主要作用。步态分析研究表明，我们行走时肌肉激活有一个有序的序列——这有助于关节的有效稳定以及向下肢的有效重量转移。臀大肌纤维几乎垂直于关节面排列，非常适合实现这一目的。股二头肌是另一个重要肌肉，它通过近端附着于骶结节韧带也能影响关节稳定性。下腰痛患者已观察到肌肉募集模式的改变。但我们不知道确切的因果关系。由于其作为上肢到下肢重量传递关键连接点的位置，关节稳定性差可能对负重产生重大影响。有人提出，骶髂关节功能障碍可能是由于负重时臀大肌运动单位募集不当所致。这会导致股二头肌代偿性过度激活。由此产生的软组织应变和关节不稳定可能表现为下腰痛。如果我们的假设成立，这可能对骶髂关节功能障碍患者有积极意义——他们可以得到明确的诊断和有针对性的物理治疗。有可能在初级保健环境中早期识别患者并直接提供物理治疗转诊。他们可以从改善受影响肌肉的强化和募集的锻炼中受益。
