Hyper-Supination

Hyper-supination is simply the opposite of hyper-pronation. Also known as high arches, this is where the foot supinates too much, for too long and at the wrong time in the gait cycle.

Incidence in the general population: Rare (3%)

As a foot with a valgus deformity goes through the Gait Cycle (the placing of one foot in front of the other in a rhythmic sequence), the already supinated position of the Sub-Talar Joint disrupts the entire gait sequence.

With the Sub-Talar Joint already supinated when the foot comes into contact with the ground, it remains in a relatively supinated position throughout the Gait Cycle. In addition, the 3-arched structure of the foot is overly tightened by the supinated position of the talus, the keystone to the medial longditudinal arch.

Supination equates to the Rigid Lever state of the foot, where the joints are tighter to enable the foot to propel the body forward. The foot should only normally act as a rigid lever during the Heel Strike and Toe-Off/Proplusion phases of the Gait Cycle, when striking power and strength/rigidity are required.

With a valgus deformity, however, the foot remains supinated, and therefore acts like a rigid lever throughout the foot flat and mid-stance phases of the Gait Cycle, when it should be more flexible and loose in order to absorb shock as the force of the body passes directly above the foot.

....Means Excessive Supination

As a result, during Foot Flat and Midstance when the weight of the entire body is over the centre of the foot, the foot is forced to "over-supinate", causing excessive tightening and tension within the foot structure and outward rotation of the lower limbs.

The over-supinated foot is not good at shock-absorption, but does provide a very strong and stable structure that allows excellent proplusion with every step. In general, there are far fewer muscle imbalance problems generated from this foot type. The majority of problems are to do with excessive wear and tear on the weight-bearing joints due to the inability of the foot to adequately absorb shock during the middle two phases of the Gait Cycle.