Comprehensive Osteopathic Medical Licensing Examination (COMLEX USA) Practice

What factors contribute to the development of spondylolisthesis?

1. Trauma alone

2. Isolated genetic predisposition

3. Bilateral spondylolysis

4. Excessive physical activity

The correct answer is: Bilateral spondylolysis

Spondylolisthesis is a condition characterized by the displacement of a vertebra, which can cause pain and neurological symptoms. One of the primary factors contributing to the development of spondylolisthesis is bilateral spondylolysis. This condition refers to a defect or fracture in the pars interarticularis of the vertebra, which is part of the vertebral arch. When the pars interarticularis is compromised on both sides, it can result in instability of the vertebra, leading to anterior slippage over the underlying vertebra. Bilateral spondylolysis often results from repetitive stress on the spine, particularly in activities that involve hyperextension of the lumbar region, which can weaken this area and ultimately result in a failure. As the vertebra becomes unstable due to this bilateral defect, it predisposes the individual to spondylolisthesis. Other factors, such as trauma or genetic predisposition, may play a role in some cases but are not the primary contributors as bilaterally weakened joints are more directly linked to the displacement seen in spondylolisthesis. Excessive physical activity can be a contributing factor if it involves repeated stress on the spine, but it does not directly cause s