Clinical Context
A typical patient is an adult with ankle instability or a neurologic foot drop resulting in gait dysfunction who is referred to orthotics for a custom-fabricated single upright ankle-foot orthosis (AFO) with a static or adjustable stop (L1920). The patient presentation often includes pain, recurrent ankle sprains, weakness of dorsiflexion, or a post-traumatic malalignment following distal tibia or fibula fracture. The clinical workflow begins with the referring physician (orthopedist, physiatrist, or podiatrist) documenting the diagnosis and functional limitations, ordering a custom AFO. An orthotist performs a detailed evaluation including gait assessment, range of motion, limb measurements and casting or 3D scanning, selects appropriate stops (e.g., plantarflexion block, dorsiflexion assist), and documents functional goals. Custom fabrication is completed by a certified orthotic facility; a fitting visit ensures appropriate alignment, pressure relief, and patient instruction on donning, skin checks, and wearing schedule. Follow‑up visits address adjustments, modifications, or repair. Typical site of service is an outpatient orthotics/ prosthetics clinic or hospital-based orthotics service. Modifier selection and documentation tie the device to the treating provider, laterality, additional services, or unusual circumstances.