Since CJS Laboratories foot orthotics are custom molded,
a good impression is imperative to assure accuracy.
Neutral position slipper casts are welcomed. The below described foam casting technique is only an option.
This technique will capture the contour of the foot with the subtalar joint in the neutral position, without any of the joints being subluxed. This can be accomplished by following these steps:
1) Evaluate subtalar joint neutral.
Lay the patient prone. Examine the contour of the longitudinal arch and look for varus of the rear foot and forefoot. The non-weight bearing foot will usually come to rest in the neutral position, that should be captured in the impression.
2) Sit the patient in a chair and line up the foot in subtalar neutral, with the hip and knee at a 90 degree angle.
The knee must be directly over the ankle.
3)
Palpate the subtalar joint, just under the malleoli, to insure STJ neutral position. Holding this position, press down on the knee driving the foot into the bottom of the impression material.
4)
With the subtalar joint still locked in neutral, press the forefoot into the impression material to a level plane with the heel, taking into consideration fore-foot varus.
5)
Remove the foot. The negative impression should reflect the foot in subtalar joint neutral, without any of the joints being subluxed, and capturing all the varus (tibial, rearfoot, and forefoot).
