KAFOs

A knee-ankle-foot orthosis (KAFO) is a rigid leg brace designed to stabilize the knee, ankle, and foot. It is used to support the affected limb after injury or in conditions that impair strength or control around the knee and ankle, enabling a more secure stance and safer gait.

Typically, a KAFO consists of a foot orthosis integrated with an ankle component, thigh and calf cuffs, and uprights that run along the leg. A knee joint connects the thigh and lower leg segments; the joint may be hinged, polycentric, or solidly locked in extension. Some designs include a stance-control or microprocessor-assisted knee mechanism to modulate knee flexion during gait.

Materials range from molded thermoplastics (often polypropylene) to carbon fiber composites or metal uprights in hybrid designs. KAFOs can be solid, locking, or adjustable; some allow free knee flexion with a separate mechanical lock engaged during standing. There are also hip-knee-ankle-foot orthoses (HKAFOs), which extend higher, but KAFOs remain the more common option when knee stabilization suffices.

Indications include neurological or muscular conditions such as spinal cord injury, polio, cerebral palsy, multiple sclerosis, stroke, or muscular dystrophies; post-surgical immobilization after knee, ankle, or foot procedures; and deformities that cause instability or unsafe gait.

Fitting is performed by an orthotist through custom measurement or impression, and may involve alignment checks from hip to foot. KAFOs require proper donning, skin inspection, and periodic adjustments. Potential limitations include increased energy expenditure during walking, reduced knee flexion in stance if locked, weight and bulk, and risk of skin irritation or pressure sores.