We speak often about the 3 foot rockers, with particular attention often to ankle rocker (ankle mortise). But one must not forget about the rear and forefoot rockers, they have their important place as well.
But, we all too often only think of these parameters when the foot is on the ground. The truth is, the swing limb is very important as well. How we swing, how the foot prepares for initial contact is also critical.
Last week Ivo wrote about toe walkers, a topic we have written about several times previously on our blog "The Gait Guys".
In this study, the researchers were appearing to look at plantarflexion posturing of the foot-ankle complex. the noted that"unilateral restricted ankle motion influenced kinematics mainly in the swing phase" as we proposed. Again, swing phase is just as critical as the stance phase of gait. One might recall our mnemonic, "when the foot is on the ground, the glutes are in charge, and when the foot is in the air, the abdominals are in charge". This admittedly is a very loose statement, but it has its place to begin the dialogue. Meaning, there is more to it. Yes, the hip flexors are key, but they have to be active on a precursor, sufficient control of the pelvis, via the abdominals in part. To this point, the researchers noted that, "hip and knee peak flexion in the swing phase were increased on the restricted side". Meaning, that to clear a plantarflexed foot-ankle complex, one might have to accentuate flexion elsewhere. No rocket science here. This is the "foot drop" strategy most of us are all to familiar with. People with foot drop have an inability to dorsiflex the ankle to clear the ground in swing, thus, to avoid tripping, one has to flex the limb higher up the chain, perhaps even hike the pelvis with the opposite leg hip abductors (plus a little frontal plane lean perhaps). This article however discusses restrictions, and not what we just discussed, loss of function.
Furthermore, "Walking with unilateral restricted ankle motion had a negative effect on walking velocity, cadence, step time, and step length."
Gait Posture. 2015 Mar;41(3):835-40.
Immediate effects of unilateral restricted ankle motion on gait kinematics in healthy subjects. Romkes J1, Schweizer K2.