Chapter 32: Orthoses for persons with postpolio sequelae

Question 1

What is postpolio sequelae?

Answer 1

A combination of Postpolio paralysis (PPP)

and Postpolio syndrome (PPS) results in overlaping complicated factors as a results of acute postpolio.

Question 2

The term poliomyelitis is derived from what greek words?

Answer 2

Polio: Gray
Myelitis: infectious process of the spinal cord.
So infection occurs exclusively in the gray matter of the spinal cord.

Question 3

How many types of polio virus are there?

Answer 3

3

Question 4

How is the polio virus transmitted to humans?

Answer 4

Through contact with infected air droplets or ingestion of ocntaminated water or other liquids.

Question 5

What vaccines are used for the polio virus?

Answer 5

Salk vaccine

Sabin vaccine

Question 6

What percent of polio survivors get postpolio syndrome?

Answer 6

25-70%

Question 7

What often causes patient to seek orthotic management of their postpolio symptoms?

Answer 7

Development of pain and weakness in the contralateral or “strong” side”

Question 8

Patient with postpolio sequelae have heightened what?

Answer 8

Sensation and may have difficulty accepting the feel of the brace.

Question 9

What is a frequent gait compensation in patients with postpolio?

Answer 9

Excessive hip flexion during limb advancement

Question 10

What are some disadvantages of the carbon fiber KAFO?

Answer 10

Skin irritation
excessive sweating
The need for exact fit
Inability to change the device after initial fabrication
No way to accomodate weight gain or swelling
Greater manufacturing time.
Greater expense.

Question 11

In the lock mode of a KAFO what degree of flexion is the knee in?

Answer 11

6 degrees

Question 12

With a stance-phase lock, what are the degrees of flexion seen?

Answer 12

17 degrees flexion and progressed to 55 degrees.

Question 13

Stance control knee joint decreased what?

Answer 13

Transverse plane pelvic rotation by 6 degrees and overall excursion through the entire gait cycle by 6 degrees.

Question 14

What questions should be asked to determine the appropriate orthotic treatment for patients with postpolio sequelae?

Answer 14

Past orthotic management
Surgical interventions
Existing painful joints
Vocation and nonvocation activities
Falls
Patient's posture
Gait analysis

Question 15

What are the goals of AFOs?

Answer 15

Stabilize and protect the joints of the foot and ankle and provide swing phase clearance and stance phase stability as well as affect knee kinematics.

Question 16

What are the common AFOs used for postpolio sequelae?

Answer 16

Posterior leaf spring AFO
Solid ankle AFO
Articualted plastic AFO
Ground reaction AFO
Articulated rear entry ground reaction AFO
Metal double upright AFO

Question 17

What does a posterior leaf spring AFO do?

Answer 17

Provides clearance of the foot through swing phase.
It has little impact during stance phase, so it requires a patient to have good stance phase stability.
It permits smooth advancement from initial contact to loading response and eliminates foot slap.

Question 18

What does a solid ankle AFO do?

Answer 18

Provid a high degree of control to the ankle-foot complex during stance. It provides good control of dorsiflexion, plantaflexion, inversion, and eversion.
It can control movement in the transverse plane.
This is good for patient’s with fused ankles

Question 19

What is often added when a patient gets a solid ankle AFO?

Answer 19

A rocker to the shoe.

Question 20

When should a rocker not be added to a shoe?

Answer 20

Patients with weak quads and feel unstable with the rocker.

Question 21

What does the articulated plastic AFO do?

Answer 21

Allows movement fore and aft, premitting the anatomical ankle to move through a specific ROM.

Question 22

What should be considered with choosing the ankle joints of an articulated plastic AFO?

Answer 22

All but the DAAJ cannot control the high loads to control dorsiflexion. So they should be limited to lightweight or limited ambulation patients.

Question 23

What does a ground reaction AFO do?

Answer 23

Provides a poeterioly directed force to the knee in stance by blocking the forward tibial advancement. It can accept the entire weight of the patient and protects the painful ankle.

Question 24

How should the ground reaction AFo be set?

Answer 24

In a few degrees of forward tilt when sitting in the shoe.

Question 25

What does the articulated rear entry ground reaction AFO do?

Answer 25

It resists the deforming forces that occur in stance phase without reinforcement.
The dorsiflexion stop can be made adjustable.
It typically allows for 5 degrees of plantaflexion and 5-10 degrees of dorsiflexion, to permit swing phase clearance and good stance pahse control without disruption of early or late stance phase rockers.
This will decrease imbalance and energy expenditure.

Question 26

When is a metal double upright AFO considered?

Answer 26

Patients with fluctuating edema or those who have worn a metal device for years and are unwilling to consider changing.

Question 27

What does the anterior compartment of a DAAJ do with a pin?

Answer 27

controls anterior tibial advancement in stance and creates a knee extension moment at heel off.

Question 28

Would a spring work in the anterior compartment?

Answer 28

NO. it is unable to efffectibely resist dorsiflexion as the patient’s body weight is transferred to the stance side.

Question 29

Should a dorsiflexion assist be used in a DAAJ?

Answer 29

Cautiously, in isolation and only in individuals who have strong plantarflexors, or else it can totally dimenish the already weakened plantarflexors.

Question 30

When should a KAFO be considered?

Answer 30

When buckling or hyperextension of the knee occurs.

It can also partially deweight the limb

Question 31

When would a quadrilateral or ischial containment KAFO design be used?

Answer 31

Patients currently wearing KAFOs and whose chief complaint is contralateral side pain, fatigue or increased weakness.

Question 32

What are the different types of knee joints?

Answer 32

Posterior offset
Drop (ring) lock
Bail and lever lock
Adjustable flexion and extension ring lock knee joints
Stance control knee joints

Question 33

Posterior offset knee joints can be used effectively when patients present with what?

Answer 33

Unilateral hyperextension of the knee.
The knee is not corrected to 180 but is set in a number of degrees of hyperextension that permits the patient to feel secure and safe in transferring his or her weight over the involved side.

Question 34

What does the posterior offset knee joint do?

Answer 34

It reduces the stress on the posterior capsule of the knee.

Question 35

Should the knee be locked in a KAFO with a posterior offset knee joint?

Answer 35

NO. It forces the patient to hike the hp and circumduct the leg, which increases energy expenditure.

Question 36

How can one determine how much hyperextension should be present in a kAFO with a posterior offset knee joint?

Answer 36

Patient holds a walker in front of them. Place the back and popliteal fossa of the involved knee against the wall. Assist the patient to slowly move his or her back closer to the wall, forcing the patient to straighten the knee. Simultaneously ask the patient if th eknee feels like it’s about to buckle. Once the patient feels like the knee is too unstable, reverse the movement until the patient feels secure again and note the angle of the knee. The orthosis should be built at this angle plus 5 degrees of hyperextension.

Question 37

When are drop (ring) locks used?

Answer 37

When patients have lower extremity weakness including weak quads.

Question 38

What is the drop lock designed to do?

Answer 38

Keep the knee locked anytime the patient is standing.

Question 39

What can be added in a drop lock that can assist the patient in unlocking the knee? What is more difficult when this is added?

Answer 39

Ball retainers

It may increase difficulty of the sit-to-stand transition because the patient must bend down to lock both sides.

Question 40

What is the bail and lever locks designed to do?

Answer 40

Permit simultaneous locking and unlocking of both the medial and lateral knee joints. It mimics the drop locks, but is easier to wear.

Question 41

What is the drawback of the bail and lever locks?

Answer 41

It can be inadvertently disengaged when bumped, causing sudden unlocking of the knee and a possible fall.

Question 42

What was made to resolve the problem of bail and lever locks from getting bumped?

Answer 42

The cable locking system

Question 43

What is the advantage of the cable locking system in a bail and lever lock knee joint?

Answer 43

it eliminates the need to bend forward to unlock the knee joints. This benefits patients with poor muscle strength or poor balance.

Question 44

What are adjustable flexion and extension rock lock knee joints designed to do?

Answer 44

Accommodate individuals with knee flexion contracture and can be adjusted to match the flexion of the patient’s knee. The ring lock will drop when the desired angle is achieved.

Question 45

What are stance control knee joints designed to do?

Answer 45

Provide the patient with a stable knee during stance phae and an automatically free knee during swing phase

Question 46

What is the advantage of the stance control knee joint over the locked knee?

Answer 46

Reduction in hip hiking and circumduction in swing and lower energy consumption.

Question 47

How do stance control knee joints operate?

Answer 47

A variety of mechanisms ranging from electronic switch activation with a microprocessor control to a simple mechanical switch.

Question 48

Stance control knee joints are good for what population?

Answer 48

Polio survivors with unilateral involvment that perviously would have required a locking knee.
No contractures and have the ability and motivation to work through a training period.

Question 49

The standard thigh section, is only useful for which patients?

Answer 49

Patients who are limited ambulators or when wearing bilateral KAFOs.

Question 50

What are the benefits of the quadrilateral and ischial containment thigh sections?

Answer 50

The transfer of weight to the involved side, extending the stance side period on the involved side and provides more effective balance to the patient’s gait and reducing stress and strain on the stronger of the patient’s legs.

Question 51

What’s a disadvantage of the metal and leather KAFO?

Answer 51

Limmited contact of the rigid bands with the limb. This reduces the amount of control possible with the device, particularly in the transverse plane.
It can also result in limb deformation within the orthosis.

Question 52

What muscles must be present to use a KAFo stance control knee joint?

Answer 52

Some hip flexor and quad strength exist.

Sufficent balance must also exist.

Question 53

What muscles are severely weak o suggest a dro plock knee joint disease?

Answer 53

Severe quad and gluteus maximus wekaness, with not hyperextension, but has severe knee buckling.

Question 54

What are the possible orthotic options for a patient who discontinued orthosis wear in childhood or adolescence. Their stronger leg is becoming fatigued more quickly or painful, or patient is tripping and falling more often.

Answer 54

AFO: Ground reaction, articulated with dorsi stop, dorsiflexion assist, and plantarflexion stop.
KAFO: on weaker side with ischial or quad style thigh section with drop lock or posterior offset knee joint, depending if there is hyperextension or not.
It will have a DAAJ with pin anteriorly and spring posteriorly.
Consider a stance control knee joint when the patient has fair-to-good hip flexors, poor-to-fair quads and sufficient balance.

Question 55

What possible orthoses should be given to a patient with unilateral painful knee with hyperextension greater than 15 degrees?

Answer 55

KAFO: Posteriorly offset knee joint, with a rigid anterior thigh section and a posterior leaf spring type AFO

Question 56

What orthoses should be given to a patient with long-term unilateral orthosis wear with a painful knee, hip or sacroiliac joint on the stronger contralateral side.

Answer 56

AFO: Ground reaction, articulated with dorsiflexion stop, dorsiflexion assist, and plantarflexion stop.
KAFO: ischial containment or quad style thigh section and locked knee.
Stance control for fair-to-good hip flexors, poor-to fair quads. and good balance.

Question 57

What orthoses should be given to a patient with a painful knee on the stronger side secondary to overuse syndrome, with grade three or higher muscle strength above and below the knee and a contralateral limb that is significantly weaker?

Answer 57

AFO: Ground reaction design with dorsiflexion stop, dorsiflexion assist, and plantarflexion stop.
KAFO: Ischial containment or quad thigh section, drop lock knee joints
KAFO: stance control knee joints and DAAJ ankle joints with springs in the posterior channel and pins in the anterior channel.

Question 58

What orthotic suggestions should be given to a long-term bilateral orthosis wearer. Possible painful joints within or above orthosis, labored gait with increased tripping and falls, and increased fatigue, pressure, and or pain from orthosis itself?

Answer 58

Suggest an improved design where deficiencies in function, components, weight, and or cosmesis exist.
Recommend more aggressive bracing when appropriate.