National Physical Therapy Examination (NPTE) Practice Exam

Which tissues respond best to very low cyclic loading to promote scar proliferation and material remodeling?

1. Bone

2. Muscle

3. Tendon

4. Ligament

The correct answer is: Ligament

The tissue that responds best to very low cyclic loading for promoting scar proliferation and material remodeling is ligament. Ligaments are dense connective tissues primarily composed of collagen, which is essential for providing stability and support to joints. When subjected to low cyclic loading, the mechanotransduction process within ligament tissue is stimulated, leading to the activation of fibroblasts and resulting in collagen synthesis and remodeling. Low cyclic loading is particularly effective in ligaments because it can enhance the biochemical environment, promoting both cellular proliferation and the organization of collagen fibers. This improved alignment of fibers contributes to the tensile strength and elasticity of the ligament, essential for its function in stabilizing joints. Other tissues, such as bone, muscle, and tendon, respond to mechanical loading differently. Bone, for instance, typically requires higher mechanical loads to stimulate remodeling effectively, while muscle responds primarily to higher intensity and resistance loading rather than low cyclic loading. Tendons also benefit from mechanical loading for healing and adaptation, but they have different optimal loading parameters compared to ligaments. In summary, ligament tissue is uniquely responsive to very low cyclic loading, which plays a critical role in the healing and remodeling processes beneficial to their function in the musculoskeletal system.