Supramalleolar Orthoses (SMOs) for Kids: Low-Profile Support

A supramalleolar orthosis (SMO) is a low brace that stops just above the ankle bones (the malleoli). It's much shorter than a full AFO and is designed to control side-to-side motion of the foot and ankle - pronation and supination - while still allowing the ankle to bend freely.

Who it's for

An orthotist may prescribe an SMO for a child with low muscle tone, flexible flat feet, or balance and stability challenges - often kids who roll their ankles inward or need help keeping the foot aligned. Because it allows ankle flexion, it supports without restricting forward movement.

What to look for in a shoe

An SMO is lower-profile than a full AFO but still adds width and depth through the foot and heel.

• A full opening to seat the foot and brace easily.
• Removable insoles to recover depth taken up by the SMO.
• Wider widths to hold the extra volume comfortably.

How BILLY fits an SMO

Because an SMO is shorter, most BILLY styles accommodate it well once you remove an insole layer and choose the right width. The Classic D|R II in Wide or Extra-Wide gives plenty of room, and the zip-around opening makes daily on-and-off easy for kids building independence.

Shop and learn more

Explore Kids' AFO Shoes and our Wide & Extra-Wide range, plus the AFO fitting guide. Your orthotist will confirm whether an SMO suits your child and help with sizing.