Gait analysis part -3

This is the third in a multi part series. If you missed part 1, click here. For part 2, click here.

Let’s rewind, There are two phases of gait: stance and swing.

Stance consists of:

 1) Heel strike
2) Loading response
3) Midstance
4) Terminal stance,  5) Pre-swing

Swing consists of:

1)initial (early) swing
2) mid swing
3) terminal (late) swing

today, we are going to discuss on miidstance

we remember that midstance is the mid point of the stance phase of the gait cycle

     Understanding midstance:

Foot:

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°.

Ankle : 

The ankle should be neutral, as it should be at the mid point of ankle rocker.

Knee:

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.

Hip:

The hip is at full flexion at loading response, decreasing as it approached midstance 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? If you don’t know what normal looks like, you will have a tougher time figuring out what is abnormal.

Reference:

1) joint structure and function Cynthia norkins