The concept of the motion barrier comes, as far as I know, from osteopathic principles, but it’s now widely distributed in the therapeutic world. Fundamentally, the idea is that tissue mobility is always limited, and that we can make clinical decisions based on our evaluation of these limitations.
In our work, we use motion barriers to tell us about the shape, degree, and direction of restrictions. One of the very interesting things about motion barriers is that the more refined our touch is, the more quickly we’ll feel motion barriers when we’re assessing tissue. A delicate touch will improve our precision in assessment, but it doesn’t make a heavier touch wrong—just less efficient. Often, students are surprised by how quickly Lauren and I evaluate tissue in the classroom. The “secret” is that we feel motion barriers with very little movement of the tissue. The second layer of the secret is that, with practice, we shift from feeling directional barriers in movement to feeling the underlying directional bias of the tissue. This second layer makes evaluation even faster. Some students find feeling bias easier than motion testing…which saves them a lot of trouble!