Photos : @ iStock . com / Oktay Ortakcioglu , Shell _ 114 , klikk with about 17 ° of ankle dorsiflexion the foot is in its mid-stance , mobile adaptive condition while applying two to three time the body weight for an extended moment as the ski edge is leveraged to make a turn . The resultant pronatory forces , as in skating and Nordic skate technique , spills energy that is required to negotiate the turn and can cause soft tissue strain as well as boot fit issues like medial ankle bone , navicular and 5th MPJ pain among other problems . I prefer a full length rigid device made to a weight bearing foot model for this fixed foot environment .
Most alpine boots are constructed with an inner insulated liner , a thermoplastic clog or bottom portion and a thermoplastic cuff . Modifications can be made to the liners by adding pads or cutting and removing material . The clogs and cuff can be modified by stretching , grinding and adding shim and heel lift components . In our lab we have a heated mandrel press to stretch the boot shells but modifications can also be made by grinding the shell or molding with a heat gun and stretching device . Heat moldable aftermarket liners are also great problem solving tool .
Proper boot fit is critical for comfort , performance and enjoyment while skiing . Among the most common fit problems are boots that are too big . This is because the path of least resistance for the ski boot salesman is selling a boot that is “ comfy ”. A boot that may feel very comfortable in the store can allow too much foot motion thus reducing the connection of the foot to the ski . Professional boot fitters will employ what is called a “ shell fit ”. This involved pulling out the liner and placing the foot inside the shell . With the toes touching the front of the shell there should only be two fingers of space behind the heel .
Small leg length discrepancies can be addressed with a heel lift inside the boot shell . Larger discrepancies are best resolved by either placing a lift between the binding and the ski or adding a lift to the toe and heel portion of the boot sole and then grinding the toe and heel lugs to fit the bindings . Both of these techniques require specialized equipment and should not be attempted by unqualified personnel .
While you may not choose to become a professional fitter yourself , having a base of knowledge of the sports and the footwear will allow you direct your patient to those who can help . Search out shops that have an experienced fitter . Develop a relationship with them and also let them know you can provide helpful guidance in solving medical conditions that , as a Pedorthist , you are uniquely qualified to treat .