AFO design considerations

Ankle–foot orthoses (AFOs) are braces designed to guide how a child’s ankle and leg move during walking. They are commonly used when children have muscle tightness, weakness, toe-walking, or differences in walking patterns.

Research shows AFOs can:

• Improve walking speed
• Increase step length
• Reduce fatigue
• Improve overall stability

However, there is no single “best” AFO. The right choice depends on your child’s muscle length, strength, balance and walking style (Morris et al.; Brehm et al.).

These braces control ankle movement to provide strong support and stability.

They are often used when a child:

• Walks on their toes
• Has reduced ankle control
• Requires a stable base for wheelchair sitting or using a standing frame
• Has a crouched or bent-knee walking pattern
• Needs strong stability through the ankle and knee

By holding the ankle in a stable position, a solid AFO can help improve knee position, walking stability, and overall efficiency. Research has shown that rigid AFOs may improve knee extension and stride length in children who need this level of control (Kunz et al., 2017).

Hinged AFOs allow the ankle to bend upward (dorsiflexion) while preventing excessive pointing down (plantarflexion).

They are typically used when:

• Full ankle range of movement is available
• The calf muscle length is adequate
• A child has good knee control but needs help preventing toe-walking
• A more natural walking pattern is desired

Because they allow controlled movement, hinged AFOs can:

• Encourage heel contact
• Improve balance and walking symmetry
• Support smoother movement during walking

Studies show articulated designs can improve walking speed and reduce energy use when muscle length and strength allow (Brehm et al.).

Careful assessment is important, as hinged designs are not suitable when significant tightness or limited ankle range is present.

These are lighter braces with built-in flexibility.

They:

• Help lift the foot during walking
• Improve step length and smoothness
• Suit milder walking differences

PLS designs provide gentle assistance rather than strong control and are often helpful when only subtle support is required (Desloovere et al.).

Dynamic AFOs vary in design, but use materials of varying stiffness to guide movement while allowing natural motion.

Since designs vary, thorough assessment is crucial. They can be suited for children who:

• Have mild weakness
• Have good range of movement
• Benefit from flexibility rather as a priority over rigid support

Research suggests these designs can improve stride length and walking efficiency in milder cases but may not provide enough control for more significant walking issues (Morris et al.).

Choosing the right type of AFO is only part of the process.

Tuning refers to adjusting how the brace works with your child’s footwear and body alignment during walking.

This may involve:

• Adjusting the ankle angle within the brace
• Adding small heel wedges to the shoe
• Modifying sole shape to influence how the foot rolls through stance

Tuning changes how forces move through the leg — particularly at the ankle and knee — during walking.

Research shows that well-tuned AFOs can:

• Improve knee alignment
• Improve step length
• Reduce walking effort by 10–20%
• Improve overall walking efficiency (Brehm et al.; Kunz et al., 2017)

Who benefits most from tuning?

Tuning is particularly important for children who:

• Have crouched or bent-knee walking patterns
• Have toe-walking patterns
• Need more precise knee control
• Show inconsistent walking patterns

Without tuning, even a well-designed AFO may not provide optimal benefit.

Tuning requires careful clinical assessment, gait observation and sometimes repeated adjustments. It is one of the key differences between simply “wearing a brace” and having a brace that truly supports efficient movement.

Across studies, AFOs improve walking outcomes — but the research quality is generally described as low to moderate because:

• Studies are often small
• Designs vary widely
• Brace stiffness and alignment are not always clearly reported

This means research gives us helpful guidance — but individual assessment remains essential (Morris et al.).

The most successful AFOs are those that:

• Match your child’s movement pattern
• Respect their muscle length and joint range
• Are tuned carefully
• Are reviewed as your child grows

AFOs influence the whole leg — not just the ankle. When chosen and adjusted carefully, they can make walking easier, more stable and less tiring.

• Brehm, M. A., et al. Effect of ankle–foot orthoses on walking efficiency in children.
• Kunz, F., et al. (2017). Influence of orthotic design and alignment on gait outcomes.
• Morris, C., et al. Orthotic management of gait: A systematic review.
• Desloovere, K., et al. Gait improvements and ankle–foot orthosis design in children.