Lower Extremity Orthotics

• Orthotics are discussed with the goal of revisiting gait

Objectives

• Identify indications and contraindications for orthotics
• Select, compare, and contrast different lower extremity orthotics to determine the most appropriate for a patient's pathology and mobility characteristics
• Considerations for orthotic use includes skin integrity, wearing, and ease of use
• Describe referral process, requirements for obtaining appropriate orthotic for a patient and potential financial implications

Session Overview

• Who needs orthotics?
• How are orthotics prescribed?
• Why are orthotics prescribed?
• What/Which orthotic should be prescribed?
• When should orthotics be prescribed?

Team Based Approach

• Involves a team of professionals
• The team typically includes the following professionals:
• Family/Caregiver
• Payer
• Physical Therapist
• Patient
• Physician/NP/PA
• Orthotist
• Starts with identification of need
• Requires patient agreeable to bracing
• Script from provider
• At times documentation of face-to-face note from MD is required (medicare)
• Meeting with orthotist
• Ideally with physical therapy
• Casting of patient's limb if required
• Fabrication of brace
• Delivery

Patient Considerations

• Consider the patient's health condition
• Consider the patient's body structure and function
• Consider the patients activities in daily life
• Consider the patients participation in daily life
• Consider environmental factors
• Consider personal factors

Indications for Orthotics

• Substitute or assist for impaired muscle performance
• Improves foot clearance in the swing phase of gait
• Provide stance phase stability and support
• Improves alignment of limb segments
• Limit joint motion or unload forces during weight bearing
• Aids healing after surgery, prevent injury to vulnerable joints
• Improves positioning limb segments for optimal function with impaired motor control and hypertonicity
• Minimize risk of bony deformity development and contracture associated with longstanding hypertonicity and/or weakness

Gait Cycle

• Phases of the gait cycle: Swing and Stance
• Instances:
• Heel/Initial Contact
• Mid stance/Foot Flat
• Terminal stance
• Pre- swing/push off
• Initial swing
• Mid swing
• Terminal swing

Biomechanical Subcomponents of Gait

• Successful walking includes:
• Generating positive step lengths
• Absence of foot drag or limb collapse
• Maintaining sagittal/frontal plane stability
• Biomechanical Subcomponents of Gait include:
• Lateral/Sagittal Stability
• Upright/Stance Control
• Propulsion
• Limb Swing

Planes of Motion

• Sagittal plane: divides the body into left and right halves
• Frontal plane: divides the body into front and back halves
• Transverse plane: divides the body into top and bottom halves

Goal of Bracing

• Assist vs Limit Motion
• Important Principles to consider in bracing
• Pressure = Force / Area
• Moment = Force x Distance, with D = level arm
• 3-Point System of Control is frequently used for bracing

Orthotic Assessment

• Determine what to observe during stance phase
• Determine what to observe during swing phase
• Note which planes of motion need to be addressed
• Determine the specific biomechanical subcomponents which are affected
• Determine which is primarily affected

LE Orthotic Categories

• The list below is the general categories
• SMO
• Off the shelf AFO
• Hinged/Articulating AFO
• Ground Reaction AFO (GRAFO)
• Solid AFO
• KAFO
• RGO/HKAFO
• Functional Electrical Stim Devices

Orthotic Considerations

• SMO (supra malleolar orthotic) contributes to Lateral/Sagittal Stability
• KAFO (Knee Ankle Foot Orthotic) contributes to Lateral/Sagittal Stability
• Solid (rigid / non-articulating/semi-rigid) contributes to Upright/Stance Control
• GRAFO (Ground Reaction AFO) contributes to Upright/Stance Control
• Articulating/Hinged contributes to Propulsion
• Off-the Shelf (flexible/dynamic) contributes to Limb Swing
• FES (Functional Electrical Stimulation) contributes to Limb Swing

Supramalleolar Orthosis (SMO)

• Indications for SMO:
• Stabilize subtalar and tarsal joints in stance
• Moderate pronation/supination
• Hypotonia
• Contraindications for SMO:
• Significant equinovarus hypertonicity
• Limited sagittal ankle/knee stability
• Controls:
• No talocrural joint control
• Moderate MTP joint control
• Moderate subtalar joint control
• Moderate midtarsal control

Off-the-Shelf/Prefabricated AFO

• Indicated to:
• Assist limb in swing, increase gait speed, and increase push off force
• Contraindicated in the presence of:
• Ankle medial/lateral instability
• Limited ankle ROM or contracture
• Moderate to severe hypertonicity
• Knee buckling or hyperextension
• Considerations include:
• Light weight, less expense, easy to don/doff, more discrete/cosmetics
• Less ability to customize
• Assist:
• DF during swing
• PF during terminal stance
• May limit knee hyperextension during stance

Hinged/Articulating AFOs

• Address Swing
• Address Stance
• Indication:
• Allows sagittal movement of tibia over foot
• Retains foot in optimal alignment
• More motion for functional mobility (STS, floor transfers, ramps/incline) - compared to solid AFO
• Contraindications:
• PF contracture
• Crouched gait or decreased knee control
• Considerations:
• Custom molded, Thermoplastic, heavier compared to other types
• More options for joint types:
• Hinges can add weight to AFO
• Variable dependent on pending hinge type:
• Strong Subtalar control
• Strong Midtarsal control

Hinged AFO Considerations

• Free Motion = Open motion at knee
• DF stop = Limit knee flexion during stance
• DF assist = Requires knee control
• PF stop = Limit knee hyperextension during stance
• Double Action Ankle Joint = Can modify over time

Ground Reaction AFO (GRAFO)

• Indications:
• Stance control/stability
• Crouch gait
• Contraindications:
• Genu recurvatum

Solid AFOs

• Made from Thermoplastic materials and can be metal double upright too
• Indications:
• Is used in Significant/global weakness/hypotonicity
• Moderate to Severe hypertonicity where significant knee extension is affecting the patient's ability to walk
• Used in the presence of Unpredictable spasticity
• When Lesser restrictive bracing has been trialed unsuccessfully
• Contraindications: =
• AFO set outside normal ROM
• Patient does not have adequate strength and hyperextension
• proximally borders 1.5 inches below the apex of the fibula to protect nerve
• Footplate is trimmed at base of the metatarsal, helping to control spasticity
• Restricts movement in all directions
• Immobilization of talocrural joint
• Subtalar joint control

KAFO or Knee-Ankle-Foot-Orthotic

• Used when AFO or knee orthosis doesn’t control the knee
• Provides stability to the knee joint
• Prevention of hyperextension
• Prevents varus or valgus during stance phase
• Some Contraindications: =
• Fixed contracture for Hip Flexors
• Leg length discrepancy of over 8 cm (3 inches)
• Impaired cognitive and learning functions
• Joints; A; Single Axis
• B; Drop lock
• C offset free or locked
• D; variable position/adjustable

Conventional KAFO

• Double Metal
• Sturdy
• Disadvantages
• Heavy
• Bulky
• Must be attached
• Good for - obesity

Thermoplastic KAFOs

• Lighter
• Can Interchange shoes
• Greater comfort
• Intimately control limb

Carbon KAFOS

• 30% more energy
• Double the cost

KAFO-Stance Control Orthoses-Microprocessor

• Variety of mechanism
• Lock knee
• Unlock at heel rise

KAFO Training Includes

• STRENGTH
• Don/doff
• Rising to standing
• Gait patterns
• Balance and coordination

Functional Electrical Stimulation (FES)

• Used for Swing phase of gait
• thigh cuffs can provide flexion in swing or knee extension in stance
• stimulation of dorsiflexors
• Some Pros are:
• therapeutic training
• custom settings
• Cons =
• limited medial/lateral stability
• Clinician knowledge
• dorsiflexion
• Estim Parameters from "M4B" needed

CPG’s say

• Early AFO = faster recovery
• Flexible AFO yields better activation
• Limited PF yields limited gains in speed
• No improvement in spasticity
• AFO = compensation/FES = therapeutic
• Solid AFO will hinder muscle gain

Clinical Practice Guideline for the Use of Ankle-Foot Orthoses and Functional Electrical Stimulation Post-Stroke major recommendations

• AFOs that allow sagittal plane motion are more effective at improving dynamic balance than AFOs that restrict motion
• AFOs that restrict motion may be more effective at improving static balance
• In chronic stroke, benefits across outcomes were seen indicating a need for continued assessment and reassessment of appropriate orthotics
• An important takeaway is that AFO may lead to more compensatory effects while FES may lead to more therapeutic effects. There is potential for improvement at any phase of the stroke recovery making it essential to reassess to make sure the device meets the needs.