Gait analysis can be used to reduce back or leg pain and increase endurance.
Walking is the most convenient way to travel short distances. Free joint mobility and appropriate muscle force increases walking efficiency. As the body moves forward, one limb typically provides support (the stance limb) while the other limb is advanced (the swing limb).
Shock absorption and energy conservation are important aspects of efficient walking. Altered joint motion or absent muscle forces may increase joint reaction (contact) forces and lead subsequently to additional pathology. In the early stance phase of gait, nearly 60 percent of one’s body weight is loaded abruptly (less than 20 milliseconds) onto the stance limb.
At initial contact, external (ground reaction) forces applied to the contact foot produce a tendency toward knee flexion. Back kneeing increases mechanical stability, but at the cost of increased contact forces and shock generation. A balance between knee stability and shock absorption is achieved by the quadriceps during the loading response. The impact of loading is minimized at the hip during single support through hip abductor muscle contraction.
Ambulation always is associated with energy costs. These costs are relatively minor in normal adults. This does not apply with gait abnormalities. Walking velocity, energy cost per time, and energy cost per distance are considerations when the patient is making choices about walking with or without adaptive aids (including the use of orthotics).
Pelvic rotation is the most important factor in energy conservation during gait. Since ankle (subtalar) motion is the primary determinant of pelvic rotation, the study of ankle motion and associated foot pressures under various conditions can give invaluable information about the impact of limb movement upon back function and vice versa. While observational gait analysis is appropriate to characterize most gait pathologies, this approach is insufficient to note abnormalities in walking as complexity increases as seen with organic pathology, such as polio, peripheral neuropathy, osteoarthritis or low back pain.
Computerized gait analysis is a logical extension of observational gait analysis. Gait analysis is: noninvasive, flexible (by definition it has to be portable), quantifiable (you can change your question from “is this horse lame?” to “How lame is this horse?”) and permanent (results can be stored on hard drive or printed out).
In the case of Electrodynography (EDG), an ultra-thin sensor is trimmed to fit inside your shoe. You then walk down a hallway and pressures are displayed and recorded in real time on a computer. The sensors allow for both qualitative and quantitative pressure data collection and can be displayed in either graphic or tabular format.
This information is invaluable in assessing the patient who complains that walking makes their back worse, or who suffers from disorders such as peripheral neuropathy, peripheral arterial disease, polio or lower extremity osteoarthritis.
Gait analysis can help determine if your walking can be improved by treating your back, if your back can be improved by treating how you walk, or if adaptive aids can be used to reduce pain, energy of ambulation or to increase endurance.