Lecture 1: Introduction to Lower Extremity Orthotics

Orthotics

(noun)

The field or specialization that we practice; the science of analyzing and creating an Orthosis

Orthotist

(noun)

Practitioner who makes, fits, and adjusts orthoses

Orthotic

(adjective)

Can be used to describe a noun (e.g. an orthotic device)

Orthosis

(noun)

The device made by the orthotist which is used to aid an existing but functionally limited part of the body

Orthoses

(noun)

Plural of Orthosis

History of orthotics

Pictorially dated back to Egyptian times.

The necessity of ambulation and ADLs forced people to create supplemental aids for the injured body.

• Canes

• Walking Sticks

• Splints

• Slings

Goals of Orthotics

Control Motion

Control Pain

Control Deformity

How to do orthotics control motion?

Stopping motion

Resisting motion

Assisting motion

How to do orthotics control pain?

Pain usually controlled by

• Limiting motion

• Stopping motion

Pain can also be controlled by

• Stress reduction in a joint through

  • Support

  • Shock-absorbing cushion

How to do orthotics control deformity?

Orthotic Forces can:

• Accommodate

  • Prevent or slow progression of deformity

• Resist

  • Prevent development or progression of deformity

• Correct

  • Decrease or correct existing deformity

What is the full name?

FO

Foot orthosis

What is the full name?

AFO

Ankle foot orthosis

What is the full name?

KAFO

Knee ankle foot orthosis

What is the full name?

KO

Knee orthosis

What is the full name?

HKAFO

Hip knee ankle foot orthosis

What is the full name?

HO

Hip orthosis

What is the full name?

THKAFO

Thoracic hip knee ankle foot orthosis

Materials used in orthotics

Metal (titanium, steel, aluminum)

Plastic (polyethylene, polypropylene)

Foam Plastic (plastazote, pelite)

Laminated Plastic (acrylic, epoxy)

Leather

Rubber

Fabric (dacron, nylon, cotton)

Composites

Classes of Orthoses

Conventional

Metal and leather

Thermoplastic

Hybrid

• Combination of conventional and thermoplastic

Arguably composites too

Conventional Orthoses

Defined by having side bars and ankle joints and some form of shoe attachment.

Originally known as the "metal" orthosis with:

• steel ankle joints

• steel stirrups

• either aluminum or steel side bars

• Aluminum calf band, leather cover

Benefits of Conventional Orthoses

Adjustable ankle

Not as hot as a thermoplastic system

Accommodates fluctuating edema

Can be very sturdy

Disadvantages of Conventional Orthoses

Can be heavy

Limited patient contact surfaces create higher pressures with less control

Wear only one pair of shoes or

Must have many shoes modified

Bulky

Ongoing maintenance

Thermoplastic Orthoses

Modified to have intimate contact over all weight bearing areas

Bony prominences relieved

Usually a vacuum-formed thermoplastic orthosis.

Benefits of Thermoplastic Orthoses

Intimate contact

• Increased control

• Decreased pressure

Fits inside shoes

• Pt can change shoes without visiting orthotist

Light weight

Cosmetic

• Fits under pants

• Patterns and such

Deficits of Thermoplastic Orthoses

Patient may be allergic to plastic

Total contact does not work well with fluctuating edema

Can be hot

Hybrid Orthoses

Defined as having characteristics of both thermoplastic and conventional orthoses

Often conventional AFO with thermoplastic footplate instead of stirrup attached to shoe

What would work?

Goal: prevent IP motion in patient’s foot to reduce pain secondary to arthritis

Orthosis: rigid FO

What would work?

Goal: redistribute pressure across entire plantar surface of patient’s insensate diabetic foot

Soft FO

What would work?

Goal: relieve aching feet secondary to flexible pes planus

Semi-rigid FO

What would work?

Goal: resist plantar flexion and allow dorsiflexion motion at the ankle for patient with drop foot

Orthosis:

Leaf spring AFO (PLS)

Articulated thermoplastic AFO with plantarflexion stop

Conventional AFO with double action ankle joints