Performance maintains and updates this glossary on a continuous basis in google docs.  Note: definitions highlighted in red or yellow are unfinished or need modification.

Contributors:

Michael Bozzaotra,  Lab Director Performance Labs

Mathew Voluck, DPM

Steven J. Pettineo, DPT, OCS

Gary Zamosky, American Board Certified Orthotist

GLOSSARY:

Abduction -  When the foot and leg are externally rotated away from the midline of the body.

Accommodative orthosis -Soft and/or Flexible shell materials are used to mold against the plantar surface of the foot. Posting and midfoot filler materials range from soft to firm in order to increase correction. The device can provide protection and absorb rather than correct the forces of abnormal foot function as well as the pressure from shock and shearing forces. Accommodative orthoses provide less control than functional orthoses that attempt to correct and align abnormal foot function.

Prescription Tip: A guideline for determining orthosis flexibility or rigidity is reverse of deformity theory. Flexible foot types get more rigid orthoses and rigid foot types get more flexible orthoses.

Acrylic – a translucent, thermoformable, rigid orthotic shell material that is highly polished and requires no top cover material. One of the first thermoplastics used in orthotic manufacturing, originally named Rohadur (which has been discontinued). Polydur, it’s slightly more flexible replacement, is used primarily in pediatrics. It is still considered a brittle acrylic that has the potential to fracture under heavier loads.

Pros: requires no top cover, rigid.

Cons: older technology compared with fiberglas and carbon fiber, can fracture, price.

Adduction - When the foot and leg are internally rotated towards the midline of the body.

Ankle Degenerative Joint Disease (DJD) - most commonly characterized as progressive loss of articular cartilage or appositional new bone formation within the ankle joint margins. In earlier stages, the cartilage is thicker than normal due to an increase in water content leading to swelling. The integrity of the articular surface is lost and vertical clefts develop leading to exposed bone.

Clinical Symptoms: include pain and stiffness typically after periods of inactivity. As disease progresses, pain may occur even at rest.

Ankle Dorsiflexion – normal gait requires around 10° of ankle dorsiflexion. Ankle range of motion is determined clinically with Silfverskiold test. In performing this test, limited range of motion with knee extended indicates boney block and soft tissue limitation in soleus/gastrocnemius. While limited range of motion with knee flexed indicates boney block and soft tissue limitation in soleus.

Anterior Tibial Shell - 

Antimicrobial Vinyl - orthosis covering material made from PVC (poly vinyl acetate) that contains impregnated silver ion antimicrobial technology to guard against bacterial growth.

Arch Height Off WB - sagittal plane height of the navicular with the foot non weight bearing, neutral subtalar joint and fully pronated midtarsal joint. With the foot in this position It is the height that the navicular bone is from a plane that the 1st MPJ, 5th MPJ and heel reside on.

Arch Height WB - sagittal plane height of the navicular with the foot in a fully weight bearing position. With the foot in this position It is the height that the navicular bone is from the ground.

Articulated Brace- Ankle Foot Orthoses (AFO’s) are comprised of a plantar foot orthotic hinged to medial and lateral uprights. The hinge points are at the center of the malleolus. The attached uprights allow the foot plate to articulate in a frontal plane. The frontal plane motion can limit or retard plantar flexion or Dorsiflexion.

Bar Post - a type of firm 70 durometer (Shore C) strip forefoot extrinsic post that extends from the medial aspect of the orthoses proximal to the 1st metatarsal at the parabola of the device that runs to the lateral side of the device behind the fifth metatarsal. The post holds the forefoot of the orthoses shell in a corrected, rectus position.

Pros: use in combination with a 1st met or 1st ray cut out for treating an uncompensated forefoot varus, use in flexible orthoses shell materials

Cons: bulky

Blake Inversion - a neutral position model of the foot is modified by simulating plantarflextion of the 1st metatarsal head so that it positions a rearfoot bisection line drawn on the posterior heel of the model, that indicates calcaneal position, to the desired inverted position. The more the 1st metatarsal is plantaflexed, the more it inverts the model. This modification is transferred to the the orthoses shell material either by vacuum forming material or direct milling the orthoses in the corrected, inverted position. As the foot rests on the corrected orthoses, it holds the rearfoot and forefoot in the inverted position.

Fabrication Steps:

Bounding Box- 3D outlined box that is present when scanning a patient's  foot with the iPad scanner equipped with a Structure sensor.  The bounding box acts as a visual boundary for the user. As the foot is positioned deeper into the bounding box, the foot changes colors from yellow to orange then rust. When the foot is orange or approximately 0.60 meters away from the user, it is at the proper distance for scanning. The bounding box can be made smaller or larger by tweezing it with the index finger and thumb to remove any unwanted background objects.

Bunion - medically defined as a progressive subluxation of the 1st metatarsophalangeal joint. The 1st metatarsal inverts relative to the hallux while the hallux subluxes into a valgus position. The abnormal position of the 1st ray as a whole can be described as a triplane deformity where the hallux is rotated with either a dorsal or plantar deviation (sagittal plane), the 1st metatarsal inverts relative to the hallux (frontal plane), and the hallux abducts and is laterally deviated from the lesser digits (transverse plane). The deformity can cause osteoarthritic symptoms including pain and stiffening within the 1st MPJ.

Bermuda Sock- STS company manufacturers a fiberglass casting sock that rolls on the foot (tune sock fashion), over the ankle or below the knee (Bermuda sock). The Fiberglas sock is manufactured in sizes that fit the patient. The sock is removed from an airtight pouch, rolled over the patient's foot/leg, lubricated with water and cures in approximately 3-5 minutes.

Note: See instruction before application.

Pros: Fast, clean

Cons: Must use and stock proper size: improper fit results in poor molding contours, price

Calcaneal Strip (Performance laboratories brand) -  a cork and rubber composite (60 durometer shore C) strip, approximately 1 inch wide positioned across the central heel that extends from the medial to lateral side. The strip stabilizes the rearfoot of the orthoses and reduces bulk when compared to a traditional rearfoot post.

Pros: low bulk

Cons: limited contact area provides less control than traditional posts.

Prescription Tip: not recommended for adult acquired flat foot or lateral ankle instability.

Calf Cuff- ankle foot orthoses uprights are attached at the posterior aspect. which stabilizes the medial and lateraluprights, Integrated one piece calf design provides intimate fit for greater control in transverse plane. One piece custom vacuum formed upright increases medial and lateral stability of the ankle joint.

Pros: reduces friction and pressure on the skin, increases control on all planes.

Cons: compliance, bulk, price

Carbon Fiber Composite - an orthosis shell material comprised of acrylic or polypropylene sandwiched between outer layers of carbon fiber. The carbon fiber weave is layered on a 45° angle as viewed from a transverse plane. this allows the composite to have directional torsion. Flexible on a sagittal plane and rigid on a frontal plane. The poly inner core enables the material to be vacuum formed over the corrected positive model.

Pros: low bulk

Cons: cost

Carbon Reinforced Nylon - nylon is impregnated with carbon fiber to increase rigidity.

Pros: low bulk

Cons: cost

Cellular Rubber (mold filler material) - is a generic open cell urethane foam that resists taking a compression set.

Poron substitute.

Channel Dispersion Pad - pads are placed on the orthoses on the medial and lateral sides of the target area but not proximally or distally. The pads start at midshaft of the rays and extend to the sulcus.

Charcot Arthropathy - a destructive arthropathy resulting from impaired pain perception and increased bone blood flow. As a result of impaired pain perception, small periarticular fractures can persist unnoticed until entire joint is destroyed. As a result of increased bone blood flow, the bones of the foot can become weak. Most commonly affected joints are within the midfoot.

Conservative Management Options: included Charcot Restraint Orthotic Walker (CROW) designed to accommodate and evenly support the foot, especially in areas overstressed by Charcot Neuropathy.

Cloth (Spenco Type) – originally designed as wetsuit material for diving. Nylon cloth material is laminated to neoprene rubber to provide minimal compression set, breathability, low friction and comfort when used  as an orthosis top covering material.

Pros: low friction, breathable

Cons: wear, fraying

Cluffy Wedge / Hallux Wedge- a firm oval shaped pad that is placed under the hallux. The pad positions the hallux so that it is in 10° of dosrsiflexion when it is resting on the pad.

Prescription Tip: Combine with reverse Morton’s extension to treat hallux rigidus.

CNC Router-  is a Computer Numerical Controll (CNC) router is a computer-controlled cutting machine related to the hand-held router used for cutting various hard materials, such as wood, composites, aluminium, steel, plastics, and foams. ... Automation and precision are the key benefits of cnc router tables.

Corner Post - a type of firm (70 durometer shore C) forefoot extrinsic post that extends from the medial (varus correction) or lateral (valgus correction) aspect of the orthotic parabola to a bisection of the third ray. Used in treating forefoot valgus or uncompensated forefoot varus.

Pros: low bulk

Cons: cannot be used with a 1st met or 1st ray cut out when treating uncompensated forefoot varus, cannot be used with flexible orthoses shells.

Cuboid Pad- a wedge shaped pad placed on the orthoses, under the cuboid. The thinnest part of the pad is on the medial side progressively getting thicker as it approaches the lateral side of the orthoses. The object of the pad is to force the cuboid back into position by inverting it and pushing it inline with the lateral column.

Prescription Tip: unfortunately, pocketing or offloading the cuboid will evert and displace it further. Along with midtarsal support, inversion and lateral wedging will provide the best outcomes.

Custom Foot Orthosis- an orthoses made for a specific individual from a cast or an image of that patient's foot.

Custom Padded Collar -  (Performance laboratories brand) Gauntlet AFO option that adds additional padding around the posterior aspect at the top of the AFO collar. Similar to the padding at the top of Timberland work boots.

            Pros: reduces friction to the skin

 Cons: none

Dancer’s Pad - an obtuse angled triangle shaped pad where the orthocenter is placed under metatarsals heads 1–5 and the area under the 1st metatarsal head is cut out. Used in the treatment of sesamoiditis.

Tip: For better outcomes, use a 1st metatarsal cut out in the orthoses shell and reverse Morton’s extension.

Delete Post - no inversion or a eversion influence is added to the heel area of the orthoses either intrinsically or extrinsically.

Pros: low bulk

Cons: makes orthoses unstable when compared to rearfoot intrinsic or extrinsic posting

Diabaguard/Osteoguard Protective Cover - (Performance laboratories brand)  A full foot, dual laminate orthosis top cover material comprised of a Plastazote as top layer (against the skin) and latex sponge underneath. Plastazote has breathable, low friction qualities and takes an accommodative compression set  providing the clinician with shearing and pressure patterns. Latex sponge has minimal compression set providing plantar pressure protection.

Pros: low friction, breathable, wear pattern compresses in material

Cons: premature wear

DM Direct Mill Orthoses - a block of polypropylene is set on a mill and the upper portion of the orthoses is milled directly into the block. Once finished, the block is flipped over so the underside of the orthoses can be milled out. Tabs are left so the orthoses can be broken away from the block. Direct mill orthoses are accurate in thickness, unlike vacuum formed orthoses that stretch and distort in the fabrication process. Subsequently, they are firmer in comparison to vacuum formed orthoses.

Pros: indestructible

Cons: none

Prescription Tip: Lower the thickness of the orthotic shell slightly to directly compare against vacuum formed orthoses shells.

Drop Foot - inability to properly dorsiflex at the ankle joint during gait. This clinical symptom can be pathologically attributed to dysfunction within the anterior and lateral compartments of the lower extremity (specifically Tibialis Anterior, Peroneal tendons) which are responsible for dorsiflexion.

        

Treatment Options: Vertibrace Dorsi Assist

Durometer - one of several measures of the hardness of a material. Higher numbers indicate harder materials; lower numbers indicate softer materials. Hardness may be defined as a material's resistance to indentation. For comparison, a mouse pad is approximately 20 durometer (Shore C) and A sneaker sole is approximately 60 durometer (Shore C)

Edema - increased fluid within the compartments of the lower extremity. Various etiologies may be attributed including vascularity dysfunctions, lymph dysfunction, and trauma. Commonly differentiated between etiologies based upon clinical observance of pitting versus non-pitting characteristics.

Engineered Nylon - an orthosis shell material that has asymmetrical thickness where the medial and lateral sides and perimeter of the heel cup of the orthoses are thinner (1.5mm) than the central aspect (2.5 mm) of the device running from the base of the heel cup to just behind the central metatarsals.

Pros: low bulk, compliance

Cons: cost

Equinus – structural or functional deformity resulting in decreased passive range of motion within the ankle joint. Equinus is defined as less than 10° of dorsiflexion at the ankle joint from a 90° angle, while 20° is considered normal passive range of motion. Equinus can be caused by an osseous block (osteoarthritic joint), muscular (shortening of the Achilles tendon) spasm (cerebral palsy), dysfunction of the fibula. Diagnosis can be assessed using the Silfverskiold test with the knee extended and flexed in determining the source of the equinus (osseous, muscular, etc.)

Treatment Options: Heel lifts, stretching of Achilles tendon.

Esprit - (Performance laboratories brand orthoses)   A polypropylene orthosis design (also available in several thin composites) providing lower bulk for men and women who wear close fitting shoes. The Esprit has a 10mm heel cup and the width runs from the lateral 5th metatarsal to the 1st interspace in order to fit in flat dress shoes and lower heels. Standard 1/16 memocell sulcus length extension and non slip heel disc prevent the device from migrating.

           

           Pros: low bulk

Cons: loss of rearfoot, midfoot and forefoot control

EVA (mold filler material) - a closed cell foam that takes a compression set. Used in Soft 20-40 durometer (Shore C) as a top cover material, medium 40-60 durometer (Shore C) as an arch filler material and firm 70-90 durometer (ShoreC) as posting material.

EVA Sport Cover - Standard 2.5mm (2mm and 3mm available), 25 durometer (Shore C) EVA foam cover. Available in solid sky blue, sand and black. Colors are color coded to match device type. Sport Covers can be substituted for standard vinyl top covers.

Pros: low friction, moderate cushioning.

Cons: wear

Extension forefoot - cushioning material that starts from the distal end of the orthotic shell and is extended to the sulcus or under the toes.

Extrinsic FF Posting (Corner, Bar, Forefoot Post to Sulcus) - A firm wedge that is adhered to the bottom of the forefoot of the orthoses that positions the forefoot and subsequently the entire orthoses in a vertical position. The extrinsic post balances a heel bisection line that is drawn on the positive model, which is resting on the orthoses, to a vertical position. This is accomplished by planning the forefoot post to the number of degrees that is needed to invert or evert the orthosis shell to correct the forefoot deformity.

Fabrication Steps:

  1. Shell material is formed on a non-weight bearing, neutral position positive cast with any forefoot deformity left uncorrected.
  2. A rubber wedge is adhered to the bottom of the forefoot of the orthoses.
  3. Both the orthoses and the neutral position casting that is resting upon it are placed on a level surface.
  4. If the forefoot of the orthoses is posted correctly, a rearfoot bisection line that is drawn on the posterior heel of the positive cast that represents calcaneal position will be vertical.

Prescription Tip: Use in the treatment of an uncompensated forefoot varus or forefoot valgus.

Extrinsic RF Post - a firm material is adhered to the heel area of the orthoses that extends from the posterior heel to the distal heel. The material is ground to the prescription value from 0° to 8° to invert or evert the orthoses shell.

Prescription Tip: If the extrinsic rearfoot post is ground to invert or evert the orthoses shell, the parabola of the orthoses will invert or evert the value that the extrinsic rearfoot post is ground to. This will result in rearfoot to forefoot motion. Example: if a 4° rearfoot varus post is prescribed, this will result in 4° of rearfoot to forefoot motion; When pressure is applied in the heel of the orthoses, the medial aspect of the parabola will be off he ground 4°. When pressure is applied to the parabola of the orthoses, the rearfoot post will evert 4° and be neutral while resting on the rearfoot posts medial aspect.

Fall Prevention Orthosis (FPO) -

Fashion Plate - (Performance laboratories brand orthoses) An orthosis design for men (fiberglass shell) and women (polypropylene shell) with a 10 mm heel cup and teardrop shape parabola. The parabola runs from the cuboid bone and is arced distally and medially proximal to the 1st metatarsal. This allows the orthosis to fit in higher heeled shoes. The top over and thin 1/16 memocell extension extend from the unique parabola to the sulcus. Standard sulcus length and the shells non-slip grip bottom cover prevent the device from migrating.

Pros: low bulk

Cons: loss of rearfoot, midfoot and forefoot control, not for use with forefoot valgus

Fiberglass Composite - bidirectional layers of fiberglass are layered to create various thicknesses using polypropylene based resin. Thicknesses range from  0.060–0.100.

Pros: cost, alternative to graphite and nylon composites

Cons: omni directional rigidity

First Met Cut Out - a radial cut in the orthosis shell where the center of the radius is the center of the 1st metatarsal head. The diameter of the radius is 20% larger than the 1st metatarsal. Any shell material that is located in the radius is cut away from the shell. Useful in the treatment of sesamoiditis.

Prescription Tip: combine a 1st met cut out with reverse Morton’s extension for better patient outcomes.

First Ray Cut Out - a transverse cut in the orthoses shell that runs from the parabola at the first metatarsal interspace, proximally and diagonally to the medial aspect of the met cuneiform joint that is used to  improve the function of the peroneus longus. Useful in the treatment of functional Hallux Limitus.

Prescription Tip: combine a 1st ray cut out with reverse Morton’s extension for better patient outcomes.

First Ray Length – the first ray length is considered elongated or shortened compared to the lengths of the lesser metatarsals. The assumed normal metatarsal length forms a parabola shape (2nd > 1st > 3rd > 4th > 5th).

The variations in the lengths of the metatarsals can cause increases in plantar pressures resulting in hyperkeratosis.

First Ray Motion (Dorsiflexed, Normal, Plantarflexed) – the range of motion of the first ray is measured with the first metatarsal held with the thumb and forefinger, while the lesser metatarsal heads are held with the thumb and forefinger of the other hand. There is no normal range of motion, however there should be about 5 mm in each direction, greater than 15mm would be considered hypermobility. If dorsiflexion is greater than plantar flexion than it is considered a dorsiflexed first ray or metatarsus primus elevatus.

-Dorsiflexed first ray can attribute to hallux abducto valgus and hallux limitus

-Plantarflexed first ray is needed if the 1st MPJ is to dorsiflex.

First Ray Position – normally the first metatarsal head should be on the same plane as the lesser metatarsals. If the 1st ray is elevated/dorsiflexed than it is considered metatarsus primus elevatus. If first ray is plantarflexed than it is considered forefoot valgus or may be attributed to dorsiflexed lateral rays.

Flex - (Performance laboratories brand orthoses) Shock absorbing orthosis design with 30 durometer arch filler and polyethylene vacuum formed shell. Shell thickness is reverse engineered by patient weight to be semi flexible, 12mm heel cup, 70 durometer EVA rear foot post and 25 durometer cellular rubber (Poron substitute) arch fill. The bottom is capped with NST non-slip grip to protect against wear and prevent migration.

Pros: shock absorption

Cons: bulk, shoe interaction

Flex/High Impact - (Performance laboratories brand orthoses) Shock absorbing orthosis design with 40 durometer arch filler and olyethylene vacuum formed shell Shell thickness reverse engineered by patient weight to be semi flexible, 12mm heel cup, 70 durometer EVA rear foot post and 40 durometer EVA arch fill. The bottom is capped with NST non-slip grip to protect against wear and prevent migration.

Pros: shock absorption, for use in heavier patients

Cons: bulk, shoe interaction

Flexible Orthoses Shell - relative to patient’s weight, the orthosis should flex

Flex SL -  Performance laboratories brand orthoses. Device is reverse engineered by patient weight to be a medium rigidity sport orthotic with vacuum formed polyethylene shell. Lab standard 12mm heel cup, width is from lateral 5th metatarsal thru a bisection of the 1st metatarsal, 70 durometer rearfoot post with polyethylene protective post cap.

Pros: compliance

Cons: long term sag and distortion

Foot Flexibility - the available range of motion in the joints of the foot; Subtalar joint, 1st metatarsophalangeal joint.


Forefoot Post to Sulcus - a firm 70 durometer (Shore C) post platform aka a Danenburg Wedge that extends from proximal aspect of the orthoses parabola to the sulcus. The extrinsic post balances a heel bisection line that is drawn on the positive model, which is resting on the orthoses, to a vertical position. This is accomplished by planning the forefoot post to sulcus to the number of degrees that is needed to invert or evert the orthosis shell to correct the forefoot deformity. This type of post allows the entire forefoot to rest on the corrected plane.

Pros: corrects entire forefoot to sulcus

Cons: bulk

Form Flex (Accommodative)- (Performance laboratories brand) flexible polypropylene shell; 1/16 inch (0 - 175 lbs) or 3/32 (>175), 12mm heel cup, post and mold filler materials are as follows;

Pros: shock absorption, compliance

Cons: bulk, shoe interaction

Form Flex (Corrective) - Performance laboratories brand orthoses a  ⅛ inch poly-propylene shell, 12mm heel cup, softer 50 durometer (Shore C) EVA rearfoot post with an additional layer of 1/16 memocell added to the extrinsic rearfoot post under the post cap that allows slightly less restrictive rearfoot correction. ⅛ inch memocell extension from heel, overshell to toes. Standard vinyl cover.

Pros: compliance

Cons: loss of rearfoot control

 

Full Foot Length - Over shell: padding from the heel of the orthoses to the end of the toes. Extension: padding blended from the distal tip of the orthotic shell running distal to the end of the toes.

Functional orthosis -semi-rigid or rigid shell materials are used to mold against the functionally corrected plantar surface of the foot model. These corrections may include expansion of the lateral heel, lowering of the medial arch and balancing of the forefoot to a vertical position. These modifications are transferred to the orthoses shell material in the forming process. Posting and midfoot filler materials range from firm to solid in order to increase correction. The device provides corrective forces to control abnormal foot function rather than to accommodate them. Functional orthoses provide more control than accommodative orthoses that attempt to absorb the forces of pressure, shock and shear.

Prescription Tip: A guideline for determining orthosis flexibility or rigidity is reverse of deformity theory. Flexible foot types get more rigid orthoses and rigid foot types get more flexible orthoses.

Gait Pattern - the analysis of the 2 lower limbs alternating between weight bearing and non-weight bearing or stance phase and swing phase. The stance phase (~65% of the gait cycle) begins with heel strike/contact and completes with heel off and toe off of the propulsive aspect of the phase. The swing phase (~35% of the gait cycle) begins immediately after toe off of the respective limb and completes immediately prior to heel strike of the limb. Abnormalities within the gait pattern can be attributed to osseous deformities or muscular imbalances.

Gaitmax - Performance laboratories brand orthoses low bulk functional device with fiberglass composite shell, calcaneal strip post made of Korex that is approximately 1 inch wide. Calcaneal strip runs from the medial to the lateral side in the heel ending wear traditional posts and reducing bulk by 35%.

Pros: low bulk with increased control

Cons: not as controlling as standard width orthosis

Gait Plate-

Half Post RF Post - 1/8 -3/16 Korex is applied to the medial or lateral bisected heel and then ground to the specified prescription value to stabilize the heel by increasing its contact surface area.

Pros: now bulk

Cons: not as controlling as traditional rearfoot Post

Hallux Limitus – a progressive deformity within the sagittal plane of the 1st metatarsophalangeal joint which can result from an osseous or functional limitation. Normal function of the 1st MPJ requires 65-75° of dorsiflexion and 40° plantarflexion.

Functional Hallux Limitus – a decreased passive range of motion in the 1st metatarsophalangeal joint with the foot loaded and in a neutral position, as opposed to a normal passive range of motion with the foot unloaded.

                        

Prescription Tip: 1st ray cut out with reverse Morton’s extension

Rigid Hallux Limitus – a decreased passive range of motion in the 1st metatarsophalangeal joint with the foot loaded and unloaded.

                        

Prescription Tip: Morton’s extension

Structural Hallux Limitus – restricted passive range of motion in the 1st metatarsophalangeal joint due to osseous deformity.

Prescription Tip:

Heel Cup Depth The depth of the heel of an orthoses measured from the center of the interior of the heel area to the top of the posterior heel rim of the orthoses.

Heel Lift – material added to the inferior surface of the heel post of the orthoses to increase the thickness of the orthotic and elevate the heel relative to the supporting surface.

Heel Pad - a Poron or Memocell (Performance brand open cell sponge) pad that covers the orthoses heel cup area.

Pros: none

Cons: loss of heel control, bulk

Prescription Tip: Heel pads lower the relative arch height of an orthoses because the heel rests upon the pad and subsequently makes the medial longitudinal arch lower by the thickness of the heel pad. This will allow the midtarsal joint to pronate further than if the pad were not present.  Additionally, a heel pad prevents the heel from residing deeper in the heel cup, which will result in a greater degree of heel eversion since the heel cup is, to a lesser degree, unable to control the heel.

Heel Spur Hole - a circular hole (1.00 "-1.50 ") punched directly through the orthoses shell and post that's filled with Poron or Memocell (Performance brand open cell sponge).

Pros: psychological

Cons: cannot be used with a medial skive

Implus (Top Cover) - Trade name for EVA top cover.

Pros: quality assurance

Cons: price

Interweave (Performance laboratories brand orthoses) Shell material is constructed of polypropylene sandwiched between two pieces of carbon fiber. The carbon fiber weave direction is layered on a 45° angle allowing the material to flex more on the sagittal plane and restricted motion on the frontal plane. The composite can be vacuum formed onto the positive model allowing deeper heel cups and excellent forming properties. Standard configuration is 12 mm heel cup, extrinsic rearfoot post and intrinsic forefoot post.

Pros: low bulk, torsional(directional) rigidity

Cons: cost

Intrinsic FF Post - a neutral position model of the foot is modified by simulating plantarflextion of the 1st metatarsal head just enough so that it positions a rearfoot bisection line, that indicates calcaneal position, to a vertical position. The more the 1st metatarsal is plantaflexed, the more it inverts the model. This modification is transferred to the the orthoses shell material either by vacuum forming material or direct milling the orthoses in the corrected position. As the foot rests on the corrected orthoses, it holds the rearfoot and forefoot in a vertical position.

Pros: low bulk

Cons: cannot be used to treat an uncompensated forefoot varus, should not be used to treat rigid forefoot valgus. In either of these cases, an extrinsic forefoot post is required.

Prescription Tip: Use in the treatment of a reducible/flexible forefoot varus.

Intrinsic RF Post - The heel area of the positive model or orthosis shell material is ground, at its resting contact point so that it positions the heel and orthoses in a vertical, inverted or everted position.

Pros: low bulk, compliance

Cons: loss of control and stability of device compared to an extrinsic rearfoot post

Prescription Tip: Use when no rearfoot deformity is present. Not recommended for treatment of adult acquired flat foot or lateral ankle instability.

Invert Cast - a neutral position model of the foot is modified by simulating plantarflextion of the 1st metatarsal head so that it positions a rearfoot bisection line, that indicates calcaneal position, to the desired inverted position. The more the 1st metatarsal is plantaflexed, the more it inverts the model. This modification is transferred to the the orthoses shell material either by vacuum forming material or direct milling the orthoses in the corrected position. As the foot rests on the corrected orthoses, it holds the rearfoot and forefoot in the inverted position.

Knee Position:

Korex (mold filler material) - 70 durometer firm cork and rubber compound. Used as arch fillers, heel lifts and the calcaneal strip post in the Gaitmax (Perfomance labs brand orthoses).

Benefits: The cork and Rubber mixture are a good blend of shock absorption and firmness. Korex does not take a compression set because the rubber compound portion is made of latex sponge.

Lap Joint -

Lateral Ankle Instability- a symptom which identifies the presence of an unstable ankle resulting from lateral ligamentous injury (ATFL, CFL, PTFL) for more than 6 months. Causes may be due from an acute sprain that fails to heal properly, torn lateral ligaments of the ankle joint, ligament laxity, muscle weakness, loss of proprioception, and/or nerve damage.

Treatment Options: ankle bracing, taping, aircast, along with physical therapy to strengthen Peroneal muscles.

Lateral Clip -  The lateral side of the heel cup of the orthoses is extended to wrap around past the plantar aspect of the heel to the lateral side of the heel. It extends 25-35 mm high, measured from the interior of the central heel cup to the top of the clip. A lateral clip is polygonal or squared off at the superior aspects of the clip.

Pros: low bulk when compared to extra deep heel seat

Cons: compliance, shoe fit

Prescription Tip: used in the treatment of genu varum and lateral ankle instability.

Lateral Flange - The lateral side of the heel cup of the orthoses is extended to wrap around past the plantar aspect of the heel to the lateral side of the heel. It extends 25-35 mm high, measured from the interior of the central heel cup. A lateral flange is elliptical or rounded of at the superior aspects of the flange.

Pros: low bulk when compared to extra deep heel seat

Cons: none

Prescription Tip: used in the treatment of genu varum and lateral ankle instability.

Lateral Malleolus - bony prominence of the lateral distal fibula bone of the lower extremity that encompases the lateral aspect of the ankle joint. This is anatomically attached at the lateral aspect of the foot by the lateral ankle ligaments (ATFL, CFL, PTFL)  and is more distal in comparison to the medial malleolus located on the medial aspect of the ankle joint.

Leather Works Mold- (Performance laboratories brand orthoses) flexible, conformable orthoses. The shell is constructed from 8-9 oz (3mm) cowhide.

The durable shell material requires filler material in the heel and midfoot to support the flexible cowhide shell. Filler materials play an important role in the function of the device because of the flexibility of the shell. Properties of the cowhide allow the orthoses to conform to the patient’s foot to provide a long lasting guard to the forces of pressure, shock and shear. Standard 12mm heel cup, firm 70 durometer rearfoot post, four soft-firm density mold filler materials available.

                   Pros: molds and conforms to patient’s foot over time. Maximum flexibility

                   Cons: absorbs moisture

Level DM (direct-mill)  (Performance laboratories brand orthoses) Orthoses is carved directly out of a block of polypropylene. Rearfoot and forefoot posts can be carved directly on to the orthoses. Direct-mill devices are carved out and not vacuum formed with heat in a bladder press, subsequently, plastic in the arch area and perimeter of the rearfoot do not stretch and distort. This makes the device more rigid in the same thicknesses as compared to traditional vacuum forming.

Pros: indestructible, 100% repeatability, predictability

Cons: firmer when compared to traditional vacuum formed orthoses; adjust thickness accordingly

Prescription Tip: lower thickness of polypropylene plastic shell material by 0.005”-0.015” to have a similar flexing action to traditional vacuum formed orthoses.

Example: (Typical polypropylene sheet thicknesses substitutes)

3/32” 0.93 = 0.85

(⅛”) 0.125 = 0.115

(5/32”)  0.156 = 0.144

(3/16”) 0.187 = 0.172

Level VF (vacuum formed) (Performance laboratories brand orthoses) The positive model is placed in a small bladder press. Plastic sheet material is heated and placed on top the positive model. Vacuum is introduced in the bladder press so the bladder pulls around the heated plastic which forms to the positive model. Distortion in the form of stretching takes place in the longitudinal arch area and the perimeter of the heel cup causing the plastic to thin out slightly giving the orthosis shell more flexibility in those regions.

Pros: compliance

Cons: unpredictable distortion when forming based on patient size

Library Device- Devices provided by an orthotic laboratory that are off-the-shelf.

 A lab that provides library devices generally has many, many sizes, widths and contours, and the device that most closely matches the patient's casts and prescription is chosen. Library devices are NOT custom.

Limb Uprights Supports - Polypropylene plates are Formed (custom one piece upright) or Sized (split upright) on the leg from the malleolus to below the knee on the medial and lateral sides. The upright supports are hinged at the center of the malleolus to a plantar foot plate. The attached uprights allow the foot plate to articulate in a sagital plane providing or limiting plantar flexion or dorsiflexion but limit motion on a frontal and transverse plane prohibiting inversion and eversion of the heel.

Medial Arch Fill - the lowering of the MLA from the bisected medial distal heel to midshaft of the 1st, 2nd and 3rd metatarsal shafts and laterally from a bisection of the 3rd ray to through the medial aspect of the foot.

Medial Cast Skive – technique that provides adequate orthotic reactive force against the calcaneus to help prevent unwanted eversion and foot pronation. The traditional cast skive inversion is set at 15° while the depth of the skive is determined in the prescription by millimeters ranging from 2mm - 6mm. Since the skive only inverts the heel it is an alternative to orthoses heel posts that invert the entire shell.

Fabrication Steps:

                     

Pros: low bulk heel inverter

Cons: none

Prescription Tip: Use when prescribing forefoot valgus as the entire plate is not inverted countering the action of the forefoot valgus post. Use for treatment of pediatric flat foot, adult acquired flat foot or tibialis posterior tendon dysfunction.

Medial Fascia Band - the medial component of the plantar fascia. This thick connective tissue supports the medial plantar arch of the foot. It runs from the medial aspect of the calcaneus to the head of the 1st metatarsal. This is most commonly affected by plantar fasciitis.

Medial Flange - shell material of the orthoses is extended from the plantar aspect of the foot to the medial side of the foot. A high medial flange may wrap around and encompass the 1st ray and/or 1st cuneiform and/or navicular. Flanges increase control, including transverse plane movement.

Pros: controls the medial column

Cons: bulk

Prescription Tip: use a low medial flange in hypermobile feet so the medial edge of the orthosis does not cause irritation. Use a high medial flange in adult acquired flatfoot (PTTD) to encompass the bones of the medial column when attempting to invert this type of foot. Combining a medial flange with an extrinsic forefoot post in a non-reducible or rigid foot type achieves better outcomes.

Medial Heel Skive (Kirby Skive) - an circular area ground into the medial heel at the medial tubercle of the calcaneal tuberosity where the depth of the grind is prescribed in millimeters when the positive cast, after the forefoot has been posted and where the heel makes contact with a level plane and the positive cast is everted 15 degrees. After the forefoot has been balanced and the forefoot of the positive cast has been everted 15°, the medial heel area that the heel rests on in this inverted position is ground where the heel makes contact with a level plane. The depth of the grinders prescribed in millimeters.The area ground into the medial heel after the forefoot has been posted and where the heel makes contact with a level plane and the positive cast is where the depth of the grind is prescribed in millimeters when the positive cast, everted 15 degrees.

Medial Malleolus- bony prominence of the medial distal tibial bone that encompases the medial aspect of the ankle joint. This is anatomically attached the medial aspect of the foot by the deltoid ligaments and is more proximal in comparison to the lateral malleolus located on the lateral aspect of the ankle joint.

Memocell – orthopedic open cell sponge w/ excellent shock-absorbing capacity. Natural open cell sponge rubber which has superior non compression set capabilities.

Pros: cost, does not take a compression set

Cons: wear, longevity

Metadductus-  

Met Bar Pad - an obtuse angled triangle shaped pad where the orthocenter is placed proximal to metatarsals heads 1–5. Used in the treatment of metatarsalgia including metatarsals 1 and 5.

Met Length - Top Cover Only: Covering material such as vinyl that covers the orthosis shell only.

Met Pad - A equilateral triangle shaped pad where the orthocenter is placed proximal to metatarsals heads 2–4. Used in the treatment of metatarsalgia.

           

                 

                 Pros: provides pressure relief for the central metatarsals (especially the 3rd mpj) where forefoot posts cannot always balance.

                 Cons: compliance

Prescription Tip: leading edge placement should be just before metatarsal heads 2-4 at the neck, lifting and supporting the rays in the hollow providing pressure relief for the central metatarsals.

Modified UCBL – orthosis used to reduce or prevent problems related to compensatory subtalar joint pronation, collapsing midfoot deformity and internal (medial) leg rotation. Orthosis functions primarily as a transverse plane stabilizer by exerting force against the shaft of the 5th metatarsal and sustentaculum tali. Sagittal and frontal plane support are provided through arch bracing and molded deep heel cup.

Morton’s Extension - A firm (70 Durometer shore C) pad that starts mid shaft of the first Ray and extends under the RAY to the end of the first metatarsal head. Used in the treatment of a non-reducible 1st metatarsal caused from elevatus or shortness of the 1st ray or hallux rigidus

Navicular - considered a tarsal bone located anatomically on the medial aspect of the foot. This is the last bone of the foot to maturely ossify and can be commonly pathologic in terms of stress fractures due to poor blood supply.

Negative Cast- the result of forming plaster, fiberglass or foam to the patient's foot.

Negative Cut Out Dispersion Pad - The target area is cut out of the extension material

Pros: low bulk

Cons: in some configurations, no protection under the target area

Neuroma Pad - an isosceles triangle shaped pad that is placed at the interspace of the neuroma with the centered behind the two metatarsal heads with a stem that extends in the interspace from the center of the pad distally to the sulcus.

Neutral Calcaneal Stance Position - With the patient standing in a full weight-bearing position, on a level surface with feet in their base angle of gait the subtalar joint is neutralized as to reveal tibial influence on the calcaneus. To assess, a bisection line of the calcaneus is measured against a perpendicular line with respect to the level surface they stand upon.

Non-Slip Grip NST - a geometric pattern is heat embossed into vinyl (poly vinyl acetate) to add a relief and dimple effect allowing the material to contain anti slip properties.

Ortholen Plastic -  German Manufactured high tensile strength plastic. Can be cold formed and highly resistant to cracking.

Ortholen - Performance laboratories brand orthoses. Device is reverse engineered by patient weight to be a semi-rigid functional orthotic with vacuum formed polyethylene shell. Lab standard 12mm heel cup, width is from lateral 5th metatarsal thru a bisection of the 1st metatarsal, 70 durometer rearfoot post with polyethylene protective post cap.

Pros: compliance

Cons: long term sag and distortion

Orthosis, Foot- an orthosis designed to support, align, prevent or correct foot deformities, or improve function of the foot. It controls excessive subtalar joint motion and balances the forefoot to a vertical or rectus position allowing for propulsive phase stability. Additionally, In the restricted or rigid foot, it provides adequate shock absorption and provides a balanced transfer of weight after heel contact. The device may also include specific additions and modifications in order to accommodate or correct specific pathologies.

Orthosis Design Exam ODE -Performance Laboratories proprietary clinical exam, and/or infographic. Forms contain quick reference rules and  guides to help in the foot orthoses prescription process.ODE forms are found at performlab.com, physician resources, reference materials.

Orthoses Width - The measurement from the lateral 5th metatarsal running at the lateral border of the orthoses, following the parabola the 1st metatarsal.

Prescription Tip: The width of the orthoses is adjusted by widening or narrowing the medial border only. Narrowing the orthoses on the lateral side will cause irritation to the bones of the lateral column.

OTC- over-counter/off the shelf
orthoses may be the same as a temporary orthoses or may be made of much more rigid, durable materials. Can be customized but are not custom. Usually chosen to match shoe size.

Overshell - Padding on top of the orthoses that runs distal from the heel cup to the metatarsals, sulcus or under the toes.

Peroneal Tendinopathy - commonly a cause of lateral ankle instability and muscle spasm within the lateral compartment of the lower extremity. Can be caused by a subluxation/dislocation or rupture of the peroneal tendons which are responsible for ankle eversion and supination of the foot during normal gait.

        Treatment Options: ankle bracing, taping

Plantar Fascial Groove - a relief or depression in the shell of the orthoses in the shape of a groove that extends under the medial band of the plantar fascia from the posterior attachment to mid shaft of the first ray.

Plaster Modification- plaster additions or subtractions are made on the positive cast in order to functionally correct or accommodate improper foot function.

Plaster additions may make the orthosis deeper in the area that the plaster is applied (such as a "pocket" for a bony prominence or a plaster modification for a plantar fascial groove).

Prescription Tip: Since most orthoses models are created in a cad/cam environment, plaster additions, modifications and corrections can be performed virtually to the digital model obtaining the same results as adding them to a plaster model.

Plastazote (mold filler material) - a 35 Durometer (Shore C) EVA (Ethylene Vinyl Acetate) closed cell foam. Plastazote will take a compression set allowing the shell of the orthoses to accommodate and set into the foam. Available as a filler material in the FormFlex Accommodative and Leather Works Mold (Both Performance brand orthoses)

Prescription Tip: Use in rigid foot structures where heel and midtarsal pronation is welcome. Combine with forefoot bar post to treat rigid forefoot valgus

Plastazote Top Cover - a 20 Durometer (Shore C) EVA (Ethylene Vinyl Acetate) closed cell foam. Plastazote will take a compression set allowing areas of the foot that are prominent to accommodate into the foam. Can be used over Memocell (Performance brand open cell sponge rubber) or Poron (Rogers Foam brand polyurethane Foam) materials to provide a dual laminate providing accommodation and resiliency. Use in the care and treatment of diabetics.

Prescription Tip: Use Plastazote (on top) and non compressible rubber dual laminate top covers as a protective layer in diabetics and to establish wear patterns in any foot type by examining the Plastazote after a few weeks of wear.

Polydor - a translucent, thermoformable, rigid orthotic shell material that is highly polished and requires no top cover material. One of the first thermoplastics used in orthotic manufacturing, originally named Rohadur (which has been discontinued). Polydur, is its slightly more flexible replacement, is used primarily in pediatrics. It is still considered a brittle acrylic that has the potential to fracture under heavier loads.

Polyethylene - a high molecular weight plastic that resists creep, sag and deformation when a repetitive load is applied. It will rebound more slowly when compared to polypropylene. Since rebound occurs more slowly, a functional orthoses feels less aggressive. Ideal for thermoforming in orthosis fabrication

Pros: compliance

Cons: long term sag and distortion

Polypropylene - a high molecular weight plastic that resists creep, sag and deformation when a repetitive load is applied. It will rebound more quickly when compared to polyethylene, having a more rapid return to its original configuration. Ideal for thermoforming and direct milling in orthosis fabrication.

Pros: no long term sag or distortion

Cons: none

Poron - is a fine pitch open cell urethane foam that resists taking a compression set produced by Rogers Corporation.

Pros: synthetic, does not take a compression set

Cons: cost

Poron Substitute - 20-30 durometer (Shore C) soft density synthetic urethane open cell rubber which has superior non-compression set capabilities.

Positive Cast- the result of filling the negative cast with liquid plaster in order to build a model of the foot.

Positive Stride - (Performance laboratories brand orthoses.)  Layered, thin, rigid fiberglass with polypropylene based resin orthoses shell material with omnidirectional rigidity. Adding more layers of Fiberglas during fabrication increases rigidity and thickness.

Pros: lower cost alternative to graphite and nylon composites

Cons: omnidirectional rigidity only

Post to Cast - 

Intrinsically- In the case of an intrinsic forefoot post, the forefoot of the positive cast is balanced so that a rearfoot bisection line on the positive cast is set to a vertical position. See Intrinsic forefoot post

Extrinsically- Posting the forefoot to cast extrinsically leaves the positive cast without forefoot correction so that when the positive cast rests on the orthosis, a medial or lateral extrinsic forefoot post is applied to the plantar aspect at the parabola of the orthoses, the positive model which is resting on the orthoses positions a rearfoot bisection line drawn on the positive cast to a vertical position.

Prescription Tip: it is not possible to post the rearfoot to cast. Since the rearfoot is held in a neutral position during the neutral position casting process, it’s deformity has been removed.

Post Plate - A thin (0.050), textured polyethylene plastic cap (Performance labs type) or other suitable material adhered to the inferior aspect of a rearfoot or forefoot post to prevent wear.

Post Wall Angle - The angle of the perimeter of an orthosis rearfoot post starting at 0°. Standard post wall angle is 7° to 10°.

Prescription Tip: decreasing the post wall angle on the medial or lateral side of the rearfoot post will increase the contact area which increases the rearfoot posts stability. Use in lateral ankle instability or adult acquired flat foot.

Pros: increases rearfoot control

Cons: increases bulk

Posterior Tibial Dysfunction - usually occurs at the area of lowest vascularity within the posterior tibial tendon behind the medial malleolus. This can cause a progressive collapse of the longitudinal medial arch of the foot and a loss of forceful inversion when weight-bearing.

        Treatment Options: medial arch support

Premium Leather - orthotic leather material comprised of the best imported top grain leathers. The cowhide is treated for any imperfections in the grain and to gain uniformity in the texture of the material. The primary advantage over standard leather material is increased water resistance.

Propulsive Wedge - A cut out under the 1st metatarsal in a forefoot posts to sulcus that is filled with softer (25 durometer shore C) material that allows the first metatarsal to plantarflex into the material allowing the 1st metatarsal to effectively move below floor grade. The cutout can be used in the treatment of functional hallux limitus.

Ray Cut Out (1st, 5th) - removal of orthosis plate, medial aspect for 1st ray cut out, lateral aspect for 5th ray cut out. Removal begins distally from the head of the respective metatarsal to its base. This allows for full plantar flexion of the respective ray.

Reduce Forefoot- the subtalar joint in put in a neutral position with one hand and the midtarsal joint is fully pronated via the fourth and fifth metatarsals or in the sulcus area of the fourth and fifth toes with the other hand (Root type cast position). Transferring the hand from the subtalar joint to the hallux, the hallux is maximally dorsiflexed with the hand that was used to neutralize the subtalar joint, concurrently ensuring that the the subtalar joint remains in a neutral position after the transition to the hallux. Maximally dorsiflexing the hallux to end range ensures plantar flexion of the first metatarsal which reduces any forefoot deformity.

placing the forefoot in a weight-bearing status similar to the phase of the gait cycle where the majority of an individual’s force is on this aspect of the foot. Reduction of the forefoot allows for proper alignment/simulation of the foot that would be in contact with the orthotic.

Reduction Cast- after wrapping the plantar surface of the foot with plaster splinting, using the STS sock or while taking a 3D scan of the plantar surface of the foot, the subtalar joint in put in a neutral position with one hand and the midtarsal joint is fully pronated via the fourth and fifth metatarsals or in the sulcus area of the fourth and fifth toes. Transfer the hand that is holding the STJ in neutral to the hallux.ensuring that the the subtalar joint remains in a neutral position.  Maximally dorsiflex the hallux with the hand that was used to neutralize the STJ. plantar flexion of the first metatarsal reduces any forefoot deformity. The reduction techniques positions the forefoot in a purpulsive state, which can be a more accurate depiction of how the parabola of the orthotic should be posted, as this is when the parabola of the orthoses it is engaged and functioning.

Pros: anatomically posts the forefoot to install any intrinsic values available in the orthoses. Simulates the Windlass Mechanism to create a full contact orthoses and post any forefoot valgus present during propulsion. Any residual varus present must be posted extrinsically.

Cons: none

the first phase in manufacturing a corrective orthotic. After reducing the subtalar joint to allow proper alignment of the foot, the medial arch is traced using a variety of casting material to create a theoretically aligned foot. The reduction cast is most commonly filled with plaster and the creation of the corrective orthotic ensues.

Reinforce Arch - Firm Korex or EVA material is placed under the MLA on the plantar aspect of the orthoses to bolster the shell material from downward forces, creep and sag.

Relaxed Calcaneal Stance Position - With the patient standing in a full weight-bearing position, on a level surface with both feet in their base angle of gait a bisection line of the calcaneus is measured against a perpendicular line with respect to the level surface they stand upon.

Reverse Morton’s Extension - a firm pad extending laterally from the first interspace to the lateral aspect of the fifth RAY and extending distally from midshaft of rays 2-5 to the sulcus of toes 2-5. Used in the treatment of functional hallux limitus and sesamoiditis

Prescription Tip: use a reverse Morton’s extension in combination with a 1st met cut out to treat sesamoiditis and in combination with the 1st Ray cut out to treat functional Hallux Limitus.

Rigid orthosis shell -

Rigid Morton’s Extension - The orthosis shell is extended under the first metatarsal head in an attempt to retard plantarflexion.

Sansone Extension- a forefoot extension of an orthoses where the hallux is cut away completely.

Scalene Triangle - a triangle where none of the corners are equal. In the case of the stealth post, the medial corner of the triangle is set at 30°, the lateral side is set at 50° and the posterior angle is set at 100°. This allows slight flexibility at the medial corner.

Scaphoid Pad - a semi-circular pad that is placed on top of the medial longitudinal arch area of an orthoses to raise the arch, buffer the impact or accommodate any subluxed bones.

Semi flexible orthosis shell -

Semi rigid orthosis shell -

Shell, Orthoses- The piece of material, whether plastic, carbon fiber, leather or other material, that conforms to the patient's foot and provides a basis for modifications and/or posting.

Shell Width- Orthoses design requires that the lateral margin of the device does not cross over the cuboid/styloid process. The shell width starts at the lateral 5th metatarsal and runs medial. The width is designated by its position with respect the the first metatarsal. The first metatarsal can be landmarked in quarters. Thin width orthoses: 1st interspace, Medium width orthoses: Bisect 1st metatarsal head, Wide orthoses width: Medial aspect of the 1st metatarsal.

Spenco Cloth Type - a neoprene open cell material that resists compression with a nylon cloth laminated to one side. Used as a common covering material in orthoses fabrications.

Standard (Orthotic Profile) Fashion orthoses have 10mm heel cups and the width funs from the lateral 5th metatarsal to the 1st interspace. Sport, Functional and Accommodative appliances have 12mm heel cups and run from the lateral 5th metatarsal to a bisected 1st metatarsal. Children's orthoses have 14mm heel cups and riling from the lateral 5th metatarsal to the medial 1st metatarsal.

Stealth Post - Performance laboratories brand. A rearfoot post constructed of carbon fiber plate in the shape of a scalene triangle where the corners are set at 30 degrees on the medial side, 50 degrees on the lateral side and the posterior angle is set at 100 degrees. This allows slight flexibility at the medial corner. The scalene plate is riveted to the orthoses in a section of the heel where the positive model was spot ground to a specific angle so the scalene plat will adopt the angle formed into the orthoses heel when riveted to it at this position.

Stealth Post- Performance laboratories brand. A low bulk carbon fiber flat plate extrinsic post fashioned in the shape of a scalene triangle that is riveted to the heel of the orthosis shell. The longer leg of the triangle is positioned on the medial side if flexing into eversion is required or on the lateral side if inversion is required.

Pros: low bulk, 80% as much contact area as traditional rearfoot post, allows flexing to achieve inversion or eversion

Cons: cost

STS Sock- An alternative foot and lower leg casting material. The sock iOS a polyester material knitted with a defined heel and toe area and then impregnated with water curable resin. See www.stsox.com

              Pros: fast, accurate

              Cons: cost, must stock sizes, shelf life (1 year)

Subtalar Joint (STJ) - joint found between the talus and calcaneus of the rearfoot. This joint allows inversion and eversion of the foot but plays no role in dorsiflexion or plantarflexion of the foot.

Structure Sensor - 3D sensor that clips to compatible mobile devices. The sensor captures detailed, full-color 3D scans of the leg and foot.

Pros: cost, size and mobility

Cons: plantar foot scanning requires two people. One to hold the foot in a neutral position and the other to scan. Users cannot hold the scanner simultaneously.

Styloid 5th Met - bony prominence located on the lateral aspect of the foot at the most proximal portion of the 5th metatarsal.

Subtalar Joint Motion Range of Motion - joint found between the talus and calcaneus of the rearfoot. This joint allows inversion and eversion of the foot but plays no role in dorsiflexion or plantarflexion of the foot. When both the anterior talocalcaneal and sinus tarsi articulations are accounted together it allows pronation and supination to occur. The majority of orthotic control is used to address over pronation within the subtalar joint.

Sulcus Length - Over shell: padding from the heel of the orthoses running distal and ending proximal to the toes. Extension: padding blended from the distal tip of the orthotic shell running distal ending proximal to the toes.

Sweet Spot - a relief or depression applied to the orthoses typically 2 mm-6mm to accommodate bone or soft tissue mass.

Tarsal Coalition - a bridge between two or more tarsal bones located in the rearfoot. This bridge can be both osseous and cartilaginous, which can restrict motion within their respective joints.

        Clinical Symptoms: include pain, restricted motion, peroneal muscle spasms

        Treatment Options: orthoses restricting range of motion in the STJ.

Thomas Heel Wedge -

Tibial Valgum- similar symptoms to genu valgum where there is a separation of the ankles relative to the knees which are medially located in full weight bearing status.  Developmentally prominent at ages 2-4 years, and 6-7 years. Pathologically indicative of rickets, Ollier’s disease, and excessive pronation of the feet.

Tibial Varum- similar symptoms to genu varum where there is a separation between the knees relative to the ankles which are medially located in full weight bearing status. Developmentally prominent at birth to 2 years of age. Pathologically indicative of rickets, Blount’s disease, and premature closure of the epiphyses (growth plates)

Toe Crest -

Toe Walking - a gait pattern that is commonly seen in individuals who are unable to fully heel strike. This can be attributed to an inability to dorsiflex at the ankle joint due to muscle spasms, bony blockades, or neurological dysfunction.

U.C.B.L An orthoses with a  deeper heel cup ranging from 16mm-32mm. The deeper the cup, the more control over the rearfoot the device can achieve.  A rearfoot post is usually prescribed to stabilize the rearfoot of the appliance. A medial flange is incorporated to control the medial column and should encompass the navicular. A lateral flange controls the cuboid/ styloid process and serves as a lateral wall to prevent the foot from sliding off the device when attempting to stabilize the midtarsal joint and hold the rearfoot and forefoot foot in a neutral, rectus position.

Prescription Tip: A U.C.B.L type device attempts to hold the foot in the same position as it appears when the rearfoot is held in subtalar joint neutral, the midtarsal joint is fully pronated and any varus forefoot deformity is reduced to a vertical position by plantarflextion of the 1st metatarsal or dorsiflexing the hallux.

U-cut Out Dispersion Pad - a pad that extends from under the midshaft of rays 1–5 to the sulcus. Under the target area is cut out of the pad. This cut out area extends distally to the end of the pad at the sulcus.

Uprights- Polypropylene plates are formed or sized to the leg from the malleolus and below the knee on the medial and lateral sides. The upright supports are hinged at the center of the malleolus to a plantar foot plate. The attached uprights allow the foot plate to articulate in a frontal plane providing or limiting plantar flexion or dorsiflexion.

U-Shaped Pad- A Poron or Memocell pad that surrounds the perimeter of the orthoses heel cup and leaves the central center and central distal area open. Heel pads lower the relative arch height of an orthoses because the heel rests upon the pad and makes the medial longitudinal arch lower by the thickness of the heel pad. This will allow the midtarsal joint to pronate further than if the pad were not present. Additionally, a heel pad prevents the heel from residing deeper in the heel cup which may result in a greater degree of heel eversion since the heel cup is to a lesser degree unable to control the heel.

Vertibrace AFO -  Performance laboratories brand AFO.  Ankle foot orthosis used with the objective to control the subtalar joint and midtarsal joint. This brace allows passive dorsiflexion at the ankle joint while stopping plantar flexion at 90 degrees.

Indications: Mild to severe drop foot with stable knee, ankle instability, and Charcot arthropathy.        

Casting Tip: Try to  maintain 90 degree plantar foot to leg relationship.. Reduce as much forefoot varus as possible by plantar flexion of the 1st metatarsal so that the 1st and 5th metatarsals are on the same plane.

-Posterior Leaf Spring AFO (PLS)- polypropylene shell-trimmed posterior to malleoli and is positioned proximally above the calf which provides a springing assistance during swing phase of gait cycle.

-Solid Ankle AFO (SAFO) - polypropylene shell-trimmed anterior to malleoli providing less flexibility at the ankle then a PLS (Posterior Leaf Spring AFO). Both are positioned proximally above the calf which provides a springing assistance during swing phase of gait cycle.

 

Vertibrace Crow Bivalve AFO -  Performance laboratories brand AFO. Supportive ankle foot orthosis boot used in the conservative management of post surgical conditions, Charcot arthropathy breakdown and prevention. Bivalve orthosis is constructed using a pretibial shell, plantar portion is formed on biomechanically corrected forefoot positive, rocker bottom 70 durometer EVA heel to toe sole and Aliplast lining.

                     

                    Casting Tip: maintain 90 degree plantar foot to leg relationship.. Reduce as much forefoot varus as possible by plantar flexion of the 1st metatarsal so that the 1st and 5th metatarsals are on the same plane.

Vertibrace Dorsi Assist-  Performance laboratories brand AFO. Ankle foot orthosis which assists in the conservative management of drop foot or tibialis anterior dysfunction. Tamarack silicone hinge hardware positions foot plate at 10 degrees of dorsiflexion at the medial and lateral malleolus. Constructed with bilateral polypropylene uprights and a balanced orthotic foot plate with extrinsic rearfoot post and intrinsic forefoot post.

Casting Tip: Try to maintain 90 degree plantar foot to leg relationship. Reduce as much forefoot varus as possible by plantarflexion of the 1st metatarsal so that the 1st and 5th metatarsals are on the same plane.

Vertibrace Dynamic AFO -   Performance laboratories brand  AFO. Ankle foot orthosis used in cases of excessive plantar flexion, toe walking, hyperextension at the knee, mild to severe ankle instability. Composed of a polypropylene shell, trimline to mid-calf.

Casting Tip: try to maintain 90 degree plantar foot to leg relationship.. Reduce as much forefoot varus as possible by plantar flexion of the 1st metatarsal so that the 1st and 5th metatarsals are on the same plane.

Vertibrace Free Motion-  Performance laboratories brand  AFO. Ankle foot orthosis used in cases of ankle instability and posterior tibial dysfunction. AFO allows for full flexion at the ankle joint with its hinge pivot screw configuration. Constructed with bilateral polypropylene uprights and a balanced orthotic foot plate with extrinsic rearfoot post and intrinsic forefoot post.d at the medial and lateral malleolus.

Casting Tip: maintain 90 degree plantar foot to leg relationship.. Reduce as much forefoot varus as possible by plantar flexion of the 1st metatarsal so that the 1st and 5th metatarsals are on the same plane.

Vertibrace Gauntlet -  Performance laboratories brand  AFO. Ankle foot orthosis used for mild to severe drop foot with stable knee and ankle stability. The gauntlet is constructed with polypropylene shell-trimmed anterior to malleoli, as well as a balanced foot plate wrapped with top-hide glove leather. Laces, Velcro or a combination closure are used for added stability.

Casting Tip: try to maintain 90 degree plantar foot to leg relationship.. Reduce as much forefoot varus as possible by plantar flexion of the 1st metatarsal so that the 1st and 5th metatarsals are on the same plane.

Vertibrace Limited Motion- Performance laboratories brand AFO. Ankle foot orthosis used in cases of ankle and subtalar degenerative joint disease, tarsal coalitions, mild Charcot arthropathy, and peroneal tendinopathy. Tamarack silicone pivot hinges with the 90 degree foot-to-leg relationship, limiting the motion in the ankle joint. Constructed with bilateral polypropylene uprights and a balanced orthotic foot plate with extrinsic rearfoot post and intrinsic forefoot post.

Casting Tip: maintain 90 degree plantar foot to leg relationship.. Reduce as much forefoot varus as possible by plantar flexion of the 1st metatarsal so that the 1st and 5th metatarsals are on the same plane.

Vertibrace Pivot Action -  Performance laboratories brand  AFO. A class of articulated hinge pivot AFO’s that are constructed of a polypropylene, balanced orthotic foot plate with standard 35mm heel cup, 0 degree extrinsic rearfoot calcaneal strip post and intrinsic forefoot post. All Pivot Action braces include hinge hardware positioned at the malleolus that may allow for free, limited or restricted action at the ankle joint. Hardware is connected to medial and lateral uprights that are prefabricated and contoured and fitted to patient's leg or fully formed to patient model with posterior calf cuff to connect the custom uprights for greater transverse plane control.

Casting Tip: try to maintain 90 degree plantar foot to leg relationship.. Reduce as much forefoot varus as possible by plantar flexion of the 1st metatarsal so that the 1st and 5th metatarsals are on the same plane.

Vertibrace Restricted Motion -  Performance laboratories brand AFO. Ankle foot orthosis used in cases of ankle and subtalar degenerative joint disease, tarsal coalitions, mild Charcot arthropathy, and peroneal tendinopathy. The limited ankle motion allows smooth contact phase of the gait cycle. Constructed with bilateral polypropylene uprights and a balanced orthotic foot plate with extrinsic rearfoot post and intrinsic forefoot post. Significant difference from the Vertibrace Limited Motion is the standard fixation at 90 degrees upright to foot relationship.

Casting Tip: maintain 90 degree plantar foot to leg relationship.. Reduce as much forefoot varus as possible by plantarflexion of the 1st metatarsal so that the 1st and 5th metatarsals are on the same plane.

Vertibrace Supra Malleolar Orthosis - (Performance laboratories brand AFO) pediatric device that maintains vertical heel alignment and improved balance during ambulation while applying corrected forces to the mid and hind foot. Controls internal or external rotation, pronation, pediatric flat foot or toe walking. Does not restrict range of motion in the sagittal plane.

Vertibrace Tamarack ROM- Performance laboratories brand  AFO. Ankle foot orthosis used in cases of ankle and subtalar degenerative joint disease, tarsal coalitions, mild Charcot arthropathy, lateral ankle instability, and peroneal tendinopathy. This AFO allows an adjustable dial-in setting for ankle dorsiflexion and plantarflexion. The Tamarack ROM in only available with custom formed bilateral polypropylene uprights and supporting calf cuff. Balanced orthotic foot plate with extrinsic rearfoot post and intrinsic forefoot post are standard.

Casting Tip: maintain 90 degree plantar foot to leg relationship.. Reduce as much forefoot varus as possible by plantar flexion of the 1st metatarsal so that the 1st and 5th metatarsals are on the same plane.

VF Vacuum Formed - flat plastic sheet is heated and vacuum formed on the positive model. Since the positive models landscape is curved around the heel and arch the plastic distorts and becomes thinner as it is stretched in the press thinning the material and allowing more flexibility.

Vinyl - polyvinyl acetate is a common orthoses top cover material used under the trade names Naugahyde. This material is very durable, long-lasting, does not absorb moisture, and is an excellent top cover along with other cushioning. However, this material may require additional cushioning for comfort and has a tendency to become hot

Pros: thin, durable and water resistant

Cons: increased friction, hot

Wet Lasted Leather - 8-9 oz leather is moistened and strapped to the positive cast so the leather will air dry and retain the shape.

White Post- Firm 70 durometer (Shore c) EVA material used as a standard material for all extrinsic posts.

Whitman or Whitman/Roberts Orthoses

Windlass Mechanism -

Zotch Notch (1st Ray Channel) - Performance laboratories brand. A modification to the shell material of an orthosis that allows plantar flexion of the first ray. Similar in function to a 1st ray cut out. However, the shell material remains in place and a groove type depression is created in the shell from the 1st met cuneiform joint. The depression runs distally to the end of the shell at the parabola  proximal the first metatarsal following the length of the 1st ray. This allows the plate to be stable while the first ray is plantarflexed. Additionally, it gives a feeling of support because no part of the shell is removed. Used in the treatment of functional hallux limitus.

Pros: orthosis plate stability and more medial column support compared to first ray cut out

Cons: none