Gait

Gait cycle

 

Definition

- from point of initial contact of one foot with the ground

- until that foot hits the ground again

 

Two parts

 

1.  Swing phase

- foot not in contact with ground

- 40% walking gait

 

2.  Stance phase

- heel strike to toe off

- 60% of walking gait

- 3 rocker phases

 

Rocker Phases

 

1st rocker phase / Heel Strike

 

Ankle plantar flexes 

The foot is lowered onto the ground under the control of the eccentrically acting tibialis anterior

Foot pronates with flattening of medial arch, and hind foot in valgus to allow show absorption

 

Lose with

- heel pain

- fixed equinus

- true or apparent LLD

 

2nd rocker phase / Stance Phase

 

Progressive  dorsiflexion of the ankle allows the tibia and the centre of gravity to progress over the foot

- modulated by the eccentrically acting triceps surae

- maximal pronation

 

3rd rocker phase / Toe Off

 

The foot rotates over the MT heads

Foot moves into supination, heel into varus

Tibialis posterior locks Midfoot so foot can act as a rigid lever

Concentric contraction of the triceps surae and FHL provides pushoff 

 

Loss

- painful forefoot (Hallux valgus / rigidus)

- loss of PF (NM, stiff hindfoot, ruptured TA)

 

Running

 

Walking ground reaction force 1.5 X body weight

Running ground reaction force 3 X body weight

 

Running has floating phase

- neither foot touching ground