College of Massage Therapists of British Columbia (CMTBC) Practice Exam

Which muscles are likely to be overstretched in cases of hyperkyphosis of the thoracic spine?

1. Rectus abdominis

2. Erector Spinae Group

3. Latissimus dorsi

4. Trapezius

The correct answer is: Erector Spinae Group

In cases of hyperkyphosis of the thoracic spine, the muscles that are likely to be overstretched are primarily those that act to extend the spine, such as the erector spinae group. Hyperkyphosis involves an excessive curvature of the thoracic spine, which often leads to a forward head posture and rounded shoulders. As a result of this posture, the erector spinae, which are responsible for maintaining an upright posture and extending the spine, can become lengthened or overstretched. When the thoracic spine is in a hyperkyphotic position, the normal tension and alignment of these muscles are disrupted. This overstretching can lead to muscle fatigue, weakness, and potentially contribute to further postural issues. The other muscle groups listed are not primarily involved in extension of the thoracic spine in the same way. The rectus abdominis is primarily involved in flexion of the trunk, the latissimus dorsi has a role in various movements including adduction and internal rotation of the shoulder, and the trapezius is more involved in scapular movement and stabilization than in maintaining thoracic extension. Therefore, their roles do not directly relate to the muscular changes occurring due to hyperkyphosis in