Lower limb orthosis

Lower limb orthosisShoe: It is the foundation of an orthosis and may be a corrective device. Well designed shoes can promote healing, prevent further injury, provide

adequate foundation for lower limb orthosis. Athletic shoes and custom designed shoes have additional components

that are important to athletes.

Foot wear: Can be modefied to redistribute weight bearing through out the foot and

ankle and can alter the forces transmitted through out the lower limb. Simple change of foot wear style or replacing a worn pair of shoes can

benfit a parson.

Shoe components

• Outer-sole: the hard layer that protect the planter surface of the foot and contacts the floor.

• Inner-sole: the softer inner layer that interface with planter surface of the foot.• Ball: the widest part of the sole located below the metatarsal heads.• Upper: divided into three parts that covers the dorsum of the foot.• Vamp: covers the anterior foot.• Tongue: an extension of the vamp that protects the foot from the eyelet rows and laces.• Quarters: medial and lateral quarters extend posteriorly, under malleolus in

low shoes or covers the malleolus in high shoes and join at the heel.• Eyelet rows: the laces are contained within the eyelet stays.• Closures or throat styles: the part that ease of donning and internal adjustability

of the shoe.• Heel: located posteriorly under the outer sole, under the anatomical heel.• Heel counter: help to maintain the anatomical heel in neutral position.• Toe box: reinforcement material, protect the anatomic toes.• Shank: between the ball and heel• Lasts: shoes are constructed over a model of the foot stylized from wood,

plaster, plastic, or computer generated design called a last

Foot orthosis (FO)

Soft Semirigid Rigid

Foot orthosis (FO)

• Foot orthosis can be classified into three general categories, soft, semi-rigid, rigid, depending on the degree of flexibility.

• Soft: flexible foam type materials provide cushioning, decrease shear forces, and to redistribute planter pressures with limited joint control.

• Semi-rigid: combination of soft and rigid materials including cork, rubber, pr plastic providing flexibility, shock absorption, designated to balance or control the foot.

• Rigid: strong, stiff and durable materials such as plastics, or metals are used to assist with transfer of weight, stabilize flexible deformities and to control abnormal motion.

Shoe modifications

External modificationsHeel corrections: Medial heel wedge Lateral heel wedge

Thomas heel Reversed Thomas heel Heel flars .

Outsole corrections:Medial sole wedges, Lateral sole wedges, Rocker bottom, Metatarsal bar.

Custom Molded Inserts

1) Univeresity of California Berkeley (UCB) insert: a molded plastic design support to the medial longitudinal arch.

2) Custom inserts: Excessive pronation or supination of the foot is corrected by controlling for rear and forefoot varus or values.

Ankle Foot Orthosis

• Ankle foot orthosis are designed to control the rate and direction of tibial advancement and to maintain an adequate base of support while meeting the specific demands for acceptable gait.

Shoe and foot attachments

Ankle joints and controls

a) Stops: 1) Planter flexion stop: a posterior stop restricting planterflexion but allowing full dorsiflexion. 2) Dorsiflexion stop: an anterior stop that restricts dorsiflexion but allows full

planterflexion. 3) Limmited motion stop: ankle joint that limits motion in all directions. 4) Free motion joint: an ankle joint that provides medial lateral stability from the

uprights while permitting full planter and dorsiflexion.

B) Assists:

1) Dorsiflexion assist: posterior spring assists with dorsiflexion and permits full planter flexion.

2) Dorsiflexion, planter flexion assist: Joints with anterior and posterior springs that assist with both planter and dorsiflexion.

Varus and valgus correction

1) Medial T-strap: The leather strap arises from the shoe quarter covering the medial malleolus and buckles to the lateral upright, pushing laterally to correct a valgus (eversion) deformity.

2) Lateral T-strap: the leather strap arises from the shoe quarter, covers the lateral malleolus and buckles to the medial upright, pushing medially to correct a varus (inversion) deformity.

3) Supramalleolar orthosis (SMO): a low-profile superamalleolar design for subtallar joint control to limit varus or valgus.

Custom molded thermoplastic ankle foot orthosis

• AFOs are custom fitted with high temperature thermoplastic materials such as polyethylene or polypropylene plastic.

• It can be molded around bony prominence and other anatomic structures, offering greater control of the foot and ankle.

• The components of AFO:

a) The shoe insert, which is often referred to as the footplate.

b) The calf shell runs the length of the posterior leg.

c) the proximal portion of the AFO has calf strap, which is typically a

velcro closure to secure the orthosis and provide some stability.

Knee- ankle foot orthosis

• To provide knee control in one or more planes.

• KAFO consists of shoe, a pair of upright metals or plastic calf shell connects the foot/ankle components to the mechanical knee joint.

Types of knee joints

1) Single axis joint: to provide medial/lateral stability, free motion joint allow full flexion and extension and prevent hyperextension. (for genu varum and genu valgum)

2) Offset axis joint: promote maximal knee extension during weight bearing. (when greater stability is necessary).

3) Poly centric axis joint: to maintain the center of rotation of the anatomic knee and to reduce excessive motion of the knee.

Knee orthotics

• Rigid KO (Knee cage): “Swedish” Knee cage, it is a prefabricated device has ametal frame with heavy elastic thigh, and calf straps are designed to prevent recurvatum and provid medial and lateral support of the knee.

• It is used for cliet having knee instability, and prevent further damage while returning strength.

Knee/ Immobilizer

• Fabricated metal inserts for stability

• Designed to restrict all motions of the knee.

• Functional knee brace.

For patient who have returned to activity and require additional stability to protect the knee .

• Patellofemoral joint: • Designed to mininize patella compression and

assist in patella guiding and prevent excessive lateral shif of the patella

• It consists of :• Elastic sleeves.• Infrapatella straps• Patellar tapping.

Bilateral KAFOs

• It is used for clients having Spinal cord lesions level L1-T12 or L1-2 to T9

• It requires:• Stability of the spine• Upper limbs strength and endurance• Shoulder girdle strength and endurance.• Normal cardiovascular and respiratory system adequate. Contra indications:• Obisity.• Hip flexion contractures• Genu varum greater than 15 degrees