There is no medical definition for an orthopedic shoe, though there are certain design features that are generally attributed to shoes that fall under the "orthopedic" classification.
These shoes, sometimes described as "comfort shoes" and also including "diabetic shoes", have particular attention paid to their comfort, fit and support and will usually have some or all of the following attributes.
1. Size selection that includes not only a standard shoe size fitting, but also separate size classifications for insole width and sometimes a further sizing for the toe box width (or toe girth) at the front of the shoe.
2. A removable insole contoured to the shape of a healthy foot with adequate cushioning to absorb walking impact and provide comfort when walking, standing or sitting. This insole should be removable, replaceable and washable. Some orthopedic shoes offer insoles made from visco elastic memory foam or gel.
3. Breathable uppers that allow air circulation and prevent the feet from becoming hot and the shoe from becoming damp. There should be adequate depth to, and the around, the areas known as the vamp "upper" and the vamp "lower" to the front of the shoe.
4. Easy fit fastenings that include hook and loop (Velcro) type methods of securing the shoe rather than shoe laces (which can provide pressure points and uneven support around the shoe tongue).
5. The lining should be seamless with no projections or areas capable of causing rubbing or abrasion. This is very important in the case of diabetic shoes where projections can result in long term foot injuries that are difficult to treat.
6. The heal collar and heel counter that supports the back of the foot (the heel) should be firm and supportive and difficult to bend or compress by hand. This feature is important for those with a tendency to pronation, or when the shoes are for walking or hiking.
7. The outer sole, any mid sole, and any flex areas should be strong and well cushioned to absorb the rigours of impact resulting from walking. However, they should still able to flex and be sufficiently tactile to pass on information about the walking surface to enable the foot to react to changing ground features and surface finishes.
8. The outer sole should not be overly wedged (i.e with a high heel) as this will prevent the natural bio mechanics of the foot from working in a healthy way.