Summary Orthotics are lower extremity supportive apparel that provide soft tissue protection, bone/joint stability and control of body segment motion. Orthotics play an important role in the nonoperative treatment of foot and ankle pathology. The type of orthotic needs to be specific for the underlying bony or ligamentous pathology in order to provide appropriate functional support. Overview Uses off-load areas of high pressure and decrease shear forces cushion vulnerable soft tissue sites (ex. diabetics) correct flexible deformities and accomdate rigid deformities (ex. pes planovalgus) eliminate painful motion (ex. hallux rigidus) replace lost motion, improve gait and ambulation (ex. ankle fusion) Options type of stabilization static: rigid device, supports body segment in fixed position dynamic: mobile device, permits body segment motion combination material metal, plastic, leather, synthetic fabric body region named for joints controlled (ankle and foot = "ankle-foot-orthosis" or AFO) Principles patient-related soft tissue at risk (diabetics) tolerant to compression and shear forces functional level of patient orthotic should match pathology being addressed soft tissue conditions flexible or rigid deformity painful motion weakness / loss of function orthotic-related three-point pressure control system should be aligned at the approximate anatomic joint design should be simple, easy to put on and take off lightweight durable aesthetically acceptable Foot Orthoses Shoes shoes are a type of orthosis can be modified to correct or accommodate deformity, minimize painful motion and optimize gait mechanics shoe selection extra depth shoe additional space allows for placement of foot orthosis and can accomodate foot deformity stiff, supportive shoe flexible foot (ex. flexible pes planovalgus) soft, accommodating shoe with shock-absorbing sole (running shoe) rigid, bony foot custom shoe severe deformity (ex. Charcot foot) shoe modifications can be internal (placed inside the shoe) or external (built up outside the shoe) internal modifications are more mechanically effective but reduced space in shoe external modifications preserve shoe volume but affect cosmesis and are more prone to wear can modify heel, sole or both adjustable closures laces, elastic laces, velcro high top lace up sneakers may help patients with poor distal proprioception provides feedback more proximally to help with balance sole excavation and padding excavation makes room for bony prominences padding cushions painful sites metatarsal pads, toe crest, scaphoid pad cushioned heel soft pad with compressible material cushions heel helpful for painful heel pad atrophy flares material added to external medial or lateral shoe provides wider base of support and increases medial-lateral stability useful for ankle instability lateral flare resists inversion medial flare resists eversion wedges internal or external sole, heel or both lateral sole wedge useful for pes cavovarus with fixed forefoot pronation, allowing entire forefoot to reach the ground without compensatory hindfoot varus medial wedge useful for flexible pes planovalgus (posterior tibial tendon dysfunction) corrects hindfoot valgus heel wedges useful for fixed varus/valgus knee deformity lateral heel wedge unloads medial compartment of the knee heel lift useful for equinus deformity or leg length discrepancy rocker soles helps transfer body weight forward can destabilize the knee by transferring body weight forward rapidly pay careful attention when prescribing to patients with balance or proprioception issues types mild rocker most common mild angle at toe and heel relieves metatarsal head pressure and assists witeh forward propulsion heel-to-toe rocker more angled at toe and heel reduces pressure at heel strike and need for ankle motion useful for patients with ankle or subtalar arthritis or fusion, midfoot amputation or calcaneal ulcers toe only rocker angled at toe increases weight bearing proximal to metatarsal heads severe angle rocker more angled at toe further decreases pressure distal to metatarsal heads useful for relief of metatarsal head or toe tip ulcerations negative heel rocker angled at toe and midfoot, with heel height lower than that of sole useful to accommodate fixed dorsiflexion deformity double rocker two shorter rocker soles centered over the forefoot and hindfoot reduces pressure at midfoot useful for midfoot prominences, such as Charcot foot extended shank embedded between the layers of the sole can be carbon fiber or steel functions as a splint, to reduce forefoot and/or midfoot motion useful for hallux rigidus (Morton's carbon-fiber extension) and midfoot arthritis Foot orthoses (inserts/inlays) Heel cup rigid plastic insert covers plantar surface of the heel and extends posteriorly, medially and laterally useful to prevent lateral calcaneal shift in flexible pes planovalgus University of California Biomechanics Laboratory (UCBL) orthosis constructed with rigid plastic over a cast of the foot held in maximum manual correction includes the heel and midfoot, with rigid medial, lateral and posterior walls holds the heel in a vertical neutral position designed for flexible pes planovalgus if deformity is rigid, the UCBL will become painful and could lead to skin breakdown Longitudinal arch support can be applied medially or laterally prevents depression of subtalar joint and corrects for pes planus Ankle Orthoses Arizona brace combination of a UCBL and lace-up ankle support useful for flexible pes planovalgus provides more rigid hindfoot support Ankle foot orthosis (AFO) construction composed of a footplate, calf support and a calf band can be made of plastic, metal and leather indications correct or prevent ankle deformity by assisting in muscular weakness or overactivity involving ankle dorsiflexion, plantarflexion, inversion or eversion ankle position indirectly affects knee stability with ankle plantarflexion providing a knee extension dorce and ankle dorsiflexion providing a knee flexion force types divided broadly into non-articulating and articulating non-articulating more aesthetically pleasing constructed of plastic, composite materials or leather and metal functionally places a flexion force on the knee during weight acceptance because they are positioned in neutral ankle position does not allow gradual eccentric plantarflexion in early stance the trim lines of plastic AFOs determine the degree of flexibility in the late stance phase described as having maximal, moderate or minimal resistance to ankle dorsiflexion articulating allows a more natural gait pattern and adjustment of plantarflexion and dorsiflexion adjustable ankle joints can be set to the desired range of ankle motion mechanical ankle joints control or assist ankle dorsiflexion or plantarflexion by means of stops or assists also control medial-lateral stability of the ankle joint limits on ankle motion affect knee stability unrestricted plantarflexion allows normal weight acceptance in early stance plantarflexion causes a knee flexion moment during weight acceptance dorsiflexion stop provides a knee extension moment during late stance specific designs posterior leaf spring (PLS) AFO most common AFO narrow calf shell and narrow ankle trim line behind malleoli used for compensating weak ankle dorsiflexors and resisting ankle plantarflexion no medial-lateral control useful for foot drop solid AFO wider calf shell with trim line anterior to malleoli prevents plantarflexion, as well as varus/valgus deviation hinged AFO adjustable ankle hinges can be set to the desired range of ankle dorsiflexion or plantarflexion (fixed) limit motion for multiplanar ankle instability or ankle pain useful for spina bifida patients with mid-lumbar level function ground reaction AFO plastic extends proximally over the pretibial area and distal trim line extends to the forefoot provides maximal resistance to plantarflexion and encourages knee extension useful for cerebral palsy patients with incompetent or overly lengthened triceps surae and mild crouch gait patellar tendon bearing AFO allows weight distribution to patellar shelf reduces weight bearing forces through foot immobilization AFO (ex. CAM walker) simple off-the-shelf AFO removable protection for lower extremity injuries that require immobilization but permit weight bearing and casting is unnecessary ex. ankle sprain, stable ankle fracture, Achilles rupture free motion ankle joint unrestricted ankle dorsiflexion and plantarflexion unrestricted dorsiflexion allows calf muscle strengthening and stretching of the plantarflexors (ex. Achilles) unrestricted plantarflexion allows normal weight acceptance in early stance provides only medial-lateral stability useful for ankle ligamentous instability plantarflexion ankle joint stop restricts plantarflexion but allows unrestricted dorsiflexion provides a knee flexion moment during weight acceptance should not be used in patients with quadriceps weakness useful for patients with foot drop during swing phase and flexible pes equinus dorsiflexion ankle joint stop restricts dorsiflexion but allows unrestricted plantarflexion promotes a knee extension moment during the loading response prevent buckling of the knee in stance in presence of quadriceps or plantarflexion weakness useful for patients with weakness of plantarflexion during stance limited motion ankle joint stop restricts both dorsiflexion and plantarflexion useful for global weakness of muscles around ankle joint dorsiflexion assist spring joint coil spring in the posterior channel counteracts plantarflexion and aids dynamic dorsiflexion during swing phase useful for dorsiflexion weakness with preserved ankle motion varus-valgus correction straps (T-straps) strap contacts skin medially and buckled to the lateral upright is used for valgus correction strap attached laterally and buckled on the medial upright is used for varus correction supramalleolar orthosis (SMO) shortest of the AFOs, ending right above the malleoli controls varus/valgus and supports heel in neutral vertical position useful for flexible pes planus, planovalgus, hyper-pronated foot Knee Orthoses Knee ankle foot orthosis (KAFO) construction consist of an AFO with medial uprights, a mechanical knee joint and two thigh bands can be made of metal, plastic and leather quadrilateral or ischial containment brim limits the weight bearing of the thigh, leg and foot indications quadriceps weakness or paralysis, to maintain knee stability flexible genu varum or valgum more difficult to place and remove than AFOs not recommended for patients with moderate to severe cognitive dysfunction specific designs double upright metal KAFO most common AFO with two metal uprights extending proximally to the thigh to control knee motion and alignment consists of a mechanical knee joint and two thigh bands between the two uprights Scott Craig orthosis cushioned heel with a T-shaped foot plate for medial-lateral stability ankle joint with anterior and posterior adjustable stops, double uprights, a pretibial band, a posterior thigh band knee joint with pawl locks and bail control hip hyperextension allows the center of gravity to fall behind the hip joint and in front of the locked knee and ankle joints with 10° of ankle dorsiflexion alignment, a swing to or swing through gait with crutches is possible used for standing and ambulation in patients with paraplegia from a spinal cord injury