Orthotics from Orthotists Perspective Flashcards
Goal of ANY Orthotic Treatment
- Limit or assist motion
- Limit deformity or pain
- Protect fragile structures –> prevent further progression, reduce stress on a joint
Choosing Appropriate Orthotic Intervention
- Previous Orthotic History
- Cognition
- Attitude
- Outside Support
- Condition of Extremity
- Muscle Tone
- Gait Evaluation
Determinants of Gait
- Pelvic Rotation
- Pelvic Tilt
- Knee Flexion at Midstance
- Foot and Ankle Motion
- Knee Motion
- Lateral Pelvic Displacement
-All influence energy expenditure and the mechanical efficiency of walking
Pelvic Tilt
- At midstance, COG reaches it’s highest point
- Pelvis tilts down on the swing side 5 degrees
- Depresses COG 3/16”
4 Questions for an orthotic prescription
-What control is needed?
-What are the deficits?
-What assistance is needed?
-What function should remain?
Basic Principles of Orthoses
- Balanced parallel force systems used to control motion
- 3 points of force application required to control motion in one plane (1 corrective, 2 stabilizing)
- The larger the corrective force, the larger the surface area required for the force application to stay within soft tissue tolerances for pressure
Metal and Leather Benefits
- Little contact on limb
- Traps little heat
- Accommodates fluctuating edema
- Structurally Sturdy
Metal and Leather Drawbacks
- Heavy
- High force with less control due to lack of contact areas
- Limited to one pair of shoes
- Bulky
- Requires more maintenance
Plastic Benefits
- Vacuum formed
- Intimate contact can be customized for more weight bearing with bony prominence relief
- Allows most biomechanical control
- Better shoe fit
- Easily Adjusted
- Colored/patterned plastics
Plastic Drawbacks
- Can be hot
- Difficult with fluctuating edema
Benefits of Carbon
- laminated to mold
- intimate contact can be customized for more weight bearing with bony prominence relief
- Allows most biomechanical
- Best shoe fit
- Lightest weight
drawbacks of carbon
not easily adjusted
5 functions of AFOs
- Block plantarflexion
- Block dorsiflexion
- Assist dorsiflexion
- Control supination (3 point pressure system)
- Control pronation (3 point pressure system)
*** can correct some deviations but might create others
Classes of Orthoses- Off the shelf
- prefabricated
- requires minimal self-adjustment (can be completed by patient or beneficiary or supplier of device)
- patient or therapist can obtain without orthotist assistance
- Generally paid for OOP or billed through hospital/therapy
classification of orthoses - custom fit
- prefabricated
- requires more than minimal self-adjustment (trimmed, bent, molded)
- requires expertise of certified orthotist to fit item on the patient
- orthotist submits to insurance fro coverage/reimbursement, more cost effective than custom fabricated
** typically seen spinal
classification of orthoses - custom fabricated
- custom (based on measurements, cast and/or digital model)
- Provides total contact
0 more control over final design since fabrication is done via orthotist - orthotists submits to insurance for coverage/reimbursement
OTS plastic AFO - Design
- One size fits most
- Plastic calf band with posterior strut to footplate
- little contact on skin, decrease risk of skin breakdown
- stops most PF
- very flexible, can be too flimsy on larger patients
OTS plastic AFO - Indications
- Neurological injuries (return of function is anticipated)
- Short term use: acute foot drop, inpatient rehab, while waiting for another device
(good when coming out of TKA or THA when nerve might have been nicked)
OTS (custom fit) carbon AFO - Design
- carbon fiber calf cuff wit posterior strut and attached foot plate (more dynamic/springiness motion through late stance into swing phase)
- Stops PF
- very lightweight and strong
OTS (Custom Fit) Carbon AFO - Indications
- foot drop (isolated)
- mild coronal ankle instability
- mild spasticity
- patient with adequate ROM to load the strut
- Mild/moderate knee buckling
OTS (Custom Fit) Carbon AFO - Contraindications
PF contractures/knee hyperextension
OTS (Custom Fit) Carbon AFO with Anterior Panel - Design
- Carbon fiber anterior panel (‘shin guard’) with strut and attached foot plate
- Provides more knee control to prevent excessive/unwanted knee flexion through stance
phase - Still provides springiness at late stance into swing phase
- Stops plantarflexion and some
dorsiflexion - Lightweight and stron
OTS (Custom Fit) Carbon AFO with Anterior Panel - Indications
- foot drop
- mild coronal ankle instability
- mild spasticity
- patient with adequate ROM to load the panel/strut
- moderate knee buckling instability
- contraindicated: PF contractures/knee hyperextension
Supramalleolar AFOs (SMOs) - Design
- Intimately fitting, low profile wrap around AFO –> Wraps around dorsum of ankle and forefoot
- Pediatric populations –> Thicker plastic needed to accommodate an adult for weight bearing (less ideal)
- Several 3 point pressure systems –> Total contact, multiplane control
- Ends 2-3” proximal to malleoli
- Can be used as an inner portion of an AF
Population that typically uses SMOs
Low tone pronators
Kids with Down syndrome
Supramalleolar AFOs - indications
- Subtalar joint instability (Low tone pronation, Poor balance/coordination, Developmental delay/gross motor skill delay)
- If talocrural joint is not controlled with FO/UCBL
- Goal is to add stability without limiting ADLs –> Allows for some PF and DF
- Contraindicated: high tone
hybrid model
better foot control, much more control for supination/ pronation
Arizona / Gauntlet Style AFO Design
- Plastic AFO wrapped in leather with laces/Valcro on dorsal to apply total contact
- Multiple 3 point pressure systems at play to limit ankle motion
Arizona / Gauntlet Style AFO Indications
- coronal ankle instability
- when unweighting/offloading ankle joint is warranted (arthritis, failed ankle fusions)
- Often when we decrease the motion, we decrease the pain
- Contraindicated for fluctuating edema, dexterity issues to lace up
Charcot Restraint Orthotic Walker (CROW) Design
- Bivalve total contact plastic boot lined with foam padding
- Designed to treat Charcot deformity and offload bony prominences / wounds
- Custom made walking boot
Charcot Restraint Orthotic Walker (CROW) Indications
- Charcot
- Open wounds/sores
- To offload foot/ankle
- typically have wounds, pitting edema
Goal:
- Provide 1 decide to last 5+ years
Most common ankle joints
tamarack and double action
tamarack ankle joint
- stretchy/gummy, have slight transverse motion
- also available in dorsiflexion assist (swing
phase clearance) - contraindicated for spasticity, can set off
clonus (substitute Oklahoma if increased tone)
Double action ankle joint
- most common on metal and leather AFOs
- Can assist/resist dorsiflexion and plantarflexion
- Infinite adjustability
- Bulky/heavy
PF Stops
- Plastic on posterior ankle of articulated AFO can stop PF
- Adjustable stops (DF can be increased within AFO to improve foot clearance)
2nd Flange (Sabolich Extension)
- Distal to the calf, proximal to malleoli
- adds coronal / rotation control to tibia
- Medial flange stops medial rotation (stops pronation)
- Lateral flange stops lateral rotation (stops supination)
Inner Boots
- SMO that fits into larger AFO
- increases frontal / triplanar control
- easier to donn larger AFO if tone is present
- can have foam ‘softy’ version for AFO
- Modular system for kids, use SMO independently of AFO for therapy settings
Anterior Panel
- increases control on foot and ankle
- can turn a solid AFO into a GRAFO (increased proximal knee control)
- easy to take off when strength improves
- Good option for patients who lack spatial skills do donn GRAFO
Slot Straps
- increases coronal / oblique control of hind foot
- redirects the tension/angle of pull more posteriorly
- medial strap reduces pronation within AFO
- lateral slot strap reduces supination within AFO
- can use both medial and lateral (figure of 8) over the ankle to lock heel inside AFO (fleshy kiddos)
Medial T Strap
reduces pronation within AFO
lateral slot T strap
reduces supination within AFO
DF Stretching Straps
- Must be on an articulated AFO
- Increases dorsiflexion
- Frequently used for nighttime stretching
- Impractical to use for daily use while ambulating
- Highly adjustable, the tighter the tension, the more dorsiflexion
DF Stop Strap
- Limits tibial progression through late stance
- Can be added to articulated AFO after the fact
- Velcro can be adjusted to allow some tibial progression before hitting end range
Rules of AFOs
- AFO is only effective if the patient can ambulate with the center of gravity over their base of support
- whenever motion is blocked, there is a compensatory deviation created
- this creates a ‘trade off’, and must be carefully balanced to result in a benefit to the patient
Foot Drop
Ankle is plantarflexed in swing phase
Deviations:
* Hip hiking
* Circumduction
* Vaulting
To correct Foot Drop
- Flexible and articulated with dorsiflexion assist joints, or plantarflexion stop
- An AFO that blocks PF will cause excessive knee flexion at loading response
Genu Recurvatum
- Knee is hyperextended at mid stance –> Shortens limb during stance phase
- Can be painful and can lead to early degeneration of knee joint
- No AFOs will correct without negative side effects
To correct genu recurvatum
we must block PF
* least invasive are semi rigid AFO or
articulated
* PF stop and free dorsiflexion
Knee Buckling
- knee buckles at mid stance, or later
- due to weak quads or pain in the knee
- No AFOs correct this without negative side effects
To correct knee buckling
we must stop dorsiflexion
* blocking dorsiflexion will stop knee flexion at
terminal stance
* least invasive have DFstop with free plantar
flexion (double action ankle joint)
* GRAFO
Knee buckling and hyperextension
- this instability can create excessive knee flexion at loading response and lack of knee flexion at terminal stance
- DF and PF must be blocked
- Looking at a solid ankle AFO
Supination
- Triplanar motion
- Lengthens limb, disturbs swing and creates a poor and unstable weight bearing structure
How is supination controlled
- Maintaining a neutral ankle with 2 three point pressure systems
- One at proximal medial calf, distal lateral fibula and medial calcaneus
- One at medial calcaneus, lateral midfoot and
medial forefoot
Supination AFO
- AFO must provide ML coverage to be effective
(no flexible styles) - Must also assist dorsiflexion or block plantarflexion
Pronation
- Triplanar motion
- Does NOT disturb swing but creates a poor and unstable weight bearing structure
How is pronation controlled?
- By maintaining a neutral ankle with 2 three
point pressure systems - one at proximal lateral calf, distal medial tibia and lateral calcaneus
- one at lateral calcaneus, medial midfoot and lateral forefoot
Pronation AFO
- AFO must provide ML coverage to be effective (no flexible styles)
- If pronation is associated with a tight heel cord, PF should be blocked
- Try to leave motion whenever possible
Function of KAFO’s
-KAFOs stabilize the lower limb
-Provide Direct control over the knee
-Can ‘unweight’ the knee, ankle or foot with a gluteal/ischial seat
-Like AFOs, these can correct some deviations, but might create other concerns
How can KAFO’s stabilize the lower limb?
longer level arm than an AFO
Which motions do KAFOs provide control over in the knee
- flexion
- extension
- valgus
- varus
KAFO Considerations
-When stance stability cannot be obtained in an AFO
-Increased weight of device increases energy expenditure… Is this functional for daily use?
* Many patients utilize KAFOs in therapeutic settings and wheelchair for longer distances (common for bilaterals)
Single Upright KAFO
- lighter
- more cosmetic
- easily re-aligned for more correction (Blounts, OA)
- Used on bilateral/RGOs
Double Upright KAFO
- Most common
- Stronger
- More torsional control
- More difficult to adjust
KAFO locked knee
- Drop locks
- Bail/lever locks
- Ratchet lock
Knee Joints Unlocked
- Free motion
- Posterior offset
- Polycentric
Locked - Drop Locks
- Lock falls into place at extension
- indications: lock automatically at full extension, simple and secure
- contraindications: need dexterity/balance to unlock
Locked - Bail/Lever Locks
- Releases with bail behind knee
or lever on lateral thigh - indications: bilateral patients, people with dexterity/balance concerns. easy to lock/unlock
- contraindications: bulky, risk for accidental unlocking (active jobs)
Locket - Ratchet Locks
- Adjustable ROM
- Extension in locking increments, unlock by pressing lever
- indications: knee flexion contractures
- contraindications: if no contracture management is needed
Unlocked - Free Motion Joints
- controls extension and coronal
control - Allows flexion
- Contraindications: when limited ROM/locked knee is required
Unlocked - Posterior Offset Joints
- Indications: provides stance stability while allowing swing flexion
- Contraindications: hip/knee contractures, or if the patient cannot reach full extension
Unlocked - Polycentric Joints
- Better mimics anatomical knee gliding motion by adding more than one center of rotation
- indications: KOs, patients with increased soft tissue, better approximates knee axis of rotation
- contraindications: bulkier, heavier
check out the indications and contraindications for KAFO knee joint stuff on 81
Gait deviations with locked knee
- Hip hiking
- Circumduction
- Vaulting
Stance Control KAFO
- Knee joint locks in response to weight
bearing - Unlocks and is in free swing during swing phase
- Mechanical driven
- Cables, switches under heel, or gravity/ pendulum to unlock
- Microprocessor driven
- Accelerometers, pressure switches electronically unlock
KAFO Additions
- 4 buckle knee pad
- 5 buckle knee pad
- Ischial weightbearing brim
- All AFO additions can be applied to AFO section of KAFO
Knee Pads 4 buckle for KAFO
Sagittal Control
* Holds knee in extension
* 4 straps around KAFO uprights to adjust tension
* Need double upright KAFO
Knee Pads 5 buckle
Coronal Control
* Holds knee in extension * Acts as a “t strap” for the knee
* Controls varus/valgus with adjustable strap
* Pulls knee into more desirable alignment
Ischial Weight Bearing Brim
- Uses principles from above knee prostheses to carry weight through ischium/pelvis –> Thigh cuff looks very similar to prosthetic socket
- Unweights hip, thigh, knee ankle and foot
- Metal ischial band or molded plastic brim
How to apply all this to patients with knee hyperextension
- Stabilize knee joint
- Need longer lever arm, cannot always control with AFO alone
- Knee orthosis often independently will not suspend nor stay in place
- If deviation is due to quad weakness, we must ensure weight line stays anterior to anatomical knee for stability
How to apply all this to pt’s with knee buckling
- Stabilize knee joint through locking knee
- Need longer lever arm, cannot always control with AFO alone
How to apply this to patients with coronal knee instability
- Free motion joint to allow flexion and block hyperextension and improve coronal alignment .
- Double upright sometimes needed for extra support
What is Functional Electrical Stimulation
- Alternative to AFOs
- Uses electrical currents to activate nerves innervating extremities affected by paralysis
- Electrodes placed over muscle belly in appropriate location to deliver targeted electrical impulses to neurons to cause contractions
Who are the candidates for FES
- Upper motor nerve or CNS disorders
- MS * CVA * TBI * Incomplete SCI
(won’t work for peripheral nerve lesions)
How does FES work?
- Through stimulating the peroneal nerve, we obtain dorsiflexion in swing phase
- Isolated foot drop only * Uses accelerometers and inclinometers to approximate legs position through gait cycle
FES Brands
- Two main brands
- WalkAide: 2 electrodes
- Bioness: 4 electrodes; more precise fitting to detect sideways motion
Benefits of FES
-Low profile design
-Can wear barefoot
* Beach
* Flip flops
-Enhanced circulation -Increased ROM
-Decrease atrophy
Downside of FES
-No insurance coverage
* Patient cost: $5500
* Maintenance, trials, will need new electrodes every few months (electrodes ~$35/each)
-Only some UMN patients are candidates
Problems to look for with ANY orthotic device
- prolonged redness (>20 mins)
- Skin irritation (blisters, bruising, abrasions, hotspots)
- Increased swelling/volume changes
Solutions for problems with orthotic device
- Break in schedule
- Add a sock/cotton barrier against skin (wicks moisture)
- Send back to orthotist (NO CHARGE FOR ADJUSTMENTS/MODIFICATIONS)
Physiological orthotic difficulties
- Awkward
- Bulky
- Cumbersome
- Slows down ability to ambulate/cadence
- Increased energy expenditure –> Is wheelchair more practical?
- Medication changes –> Change in volume/swelling
- Insensate skin less likely to notice problems
Psychosocial Orthotic Difficulties
- Cosmesis
- Others can see the disability
- KAFO joints are bulky
- Difficult to hide under clothes
- Draws more attention to themselves
Practicality orthotic difficulties
Support team at home:
* Difficult to donn independently
* Too time consuming to donn
Discomfort:
* Groin for KAFOs when sitting
* Bulk under thigh
* Keeping ankle fixed at one angle
Expense
When in doubt…
- Call your orthotist –> You spend more time and get to know your patients more than we do
- We are certified / licensed individuals just like you all working towards the same goal of bettering our patient’s lives