So you want to do a Gait Analysis: Part 3
Again, a quick review of the walking gait cycle components:
There are two phases of gait: stance and swing.
Stance consists of:
- Initial contact
- Loading response
- Terminal stance
Swing consists of:
- initial (early) swing
- mid swing
- terminal (late) swing
today, lets explore Midstance
we remember that midstance is the mid point of the stance phase of the gait cycle. It is when the maximal amount of midfoot pronation should be occurring
Lets look at what is happening here at the major anatomical areas:
- Pronation begins: The talus should have slid anteriorly on the calcaneus and it then plantar flexed, everted and adducted to its greatest degree. The subtalar joint should have its axes parallel with the calcaneocuboid joint, essentially “unlocking” the midfoot. This allows the midfoot to assist in absorbing shock, along with knee flexion, hip flexion and a dip of the contralateral pelvis.
- the calcaneus everts to a max of approximately 5-8°
- the center of gravity of the foot is lowest at this point, and the ankle mortise its deepest.
- The lower leg should be internally rotated (as it follows the talus) 4-6°
- The thigh should follow the lower leg and should also be internally rotated 4-6°; sometimes to a greater extent due to the shape and size of the medial condyle of the femur (which is larger than the lateral)
- these actions are (still) attenuated by eccentric action of both the long flexors and extensors of the ankle, as well as the foot intrinsics
- The ankle should be neutral, as it should be at the mid point of ankle rocker
- Flexion to 20°. This is attenuated largely by the quadriceps, contracting eccentrically. The popliteus has often concentrically contracting to assist in internal rotation of the thigh up until midstance. It is quiescent at midstance and will begin to contract eccentrically as soon as the knee passes midstance.
- The hip is at full flexion at loading response, decreasing as it approached midtsnce and now begins to extend. This is facilitated by a brief contraction of the gluteus maximus (which started at initial contact)
Can you see what is happening? Try and visualize this in your mind. Can you understand why you need to know what is going on at each phase to be able to identify problems? If you don’t know what normal looks like, you will have a tougher time figuring out what is abnormal.
Ivo and Shawn. Gait and foot geeks extraordinaire. Helping you to build a better foundation to put all this stuff you are learning on.