Final answer:
The Multifidus Triangle appears to be a typographical error, and the question likely refers to the multifidus muscle located in the lumbar region, assisting in extending, rotating, and laterally flexing the vertebral column.
Step-by-step explanation:
The Multifidus Triangle is not a common anatomical term and seems to be a typographical error in the presented question. However, based on relevant context, the student might be referring to the multifidus muscle, which is a part of the deep musculature of the spine. The multifidus muscle is a multipennate muscle situated in the lumbar region and plays a crucial role in stabilizing the joints within the spine. It helps to extend, rotate, and laterally flex the vertebral column. This muscle extends throughout the length of the spine but is most prominent in the lumbar region and can be implicated in lower back pain if dysfunctional.