LE Orthotics

Question 1

How do you identify the anatomic knee joint center?

Answer 1

Find the level of the adductor tubercle and the level of the medial tibial plateau. The knee joint center is the midpoint

Question 2

Describe what happens when the orthotic knee joint is located proximal to the anatomic knee joint center.

Answer 2

The thigh band moves distal with respect to the leg
Pressures on the thigh will be anterior proximal and posterior distal
Pressure on the leg/calf will be anterior

Question 3

Describe what happens when the orthotic knee joint is located distal to the anatomic knee joint center.

Answer 3

The thigh band moves proximal with respect to the leg
Pressures on the thigh will be anterior distal and posterior proximal
Pressure on the leg/calf will be posterior

Question 4

Describe what happens when the orthotic knee joint is located anterior to the anatomic knee joint center.

Answer 4

The thigh band moves distal with respect to the leg.
Pressures on the thigh will be anterior distal and posterior proximal
Pressure on the leg/calf will be anterior

Question 5

Describe what happens when the orthotic knee joint is located posterior to the anatomic knee joint center.

Answer 5

The thigh band moves proximal with respect to the leg.
Pressures on the thigh will be anterior proximal and posterior distal
Pressure on the leg/calf will be posterior

Question 6

Describe what happens when the orthotic ankle joint is located anterior to the anatomic joint.

Answer 6

Calf band will move posterior and proximal with dorsiflexion; pressure will be anterior
Calf band will move posterior and distal with plantarflexion; pressure will be anterior

Question 7

Describe what happens when the orthotic ankle joint is located posterior to the anatomic joint.

Answer 7

Calf band will move anterior and distal with dorsiflexion; pressure will be posterior
Calf band will move anterior and proximal with plantarflexion; pressure will be posterior

Question 8

Describe what happens when the orthotic ankle joint is located proximal to the anatomic joint.

Answer 8

Calf band will move posterior and distal with dorsiflexion; pressure will be anterior
Calf band will move anterior and distal with plantarflexion; pressure will be posterior

Question 9

Describe what happens when the orthotic ankle joint is located distal to the anatomic joint.

Answer 9

Calf band will move anterior and proximal with dorsiflexion; pressure will be posterior
Calf band will move posterior and proximal with plantarflexion; pressure will be anterior

Question 10

How does a pin in the anterior channel function?

Answer 10

Dorsiflexion stop

Question 11

How does a pin function in the posterior channel?

Answer 11

Plantarflexion stop

Question 12

How does a spring in the anterior channel function?

Answer 12

Dorsiflexion resist, plantarflexion assist

Question 13

How does a spring in the posterior channel function?

Answer 13

Plantarflexion resist, dorsiflexion assist

Question 14

What columns of the spine are involved in a compression fracture?

Answer 14

Anterior

Question 15

What columns of the spine are involved in a burst fracture?

Answer 15

Anterior and middle

Question 16

What compartments might be impacted in a fracture-dislocation? How might they be impacted?

Answer 16

Anterior failure due to compression and rotational shear
Middle failure due to distraction and rotational shear
Posterior failure due to rotational shear

Question 17

What is a hangman’s fracture?

Answer 17

Traumatic spondylolisthesis of the axis (C2); C2 slips anterior (HALO indicated)

Question 18

What vertebrae is involved in a Jefferson fracture? What orthosis is indicated?

Answer 18

C1

HALO

Question 19

What is an odontoid fracture? What is the mechanism of injury? What orthosis is indicated?

Answer 19

C2 involvement
Shear and compression
HALO indicated

Question 20

Where is the initial position for pins for a HALO? How many pins? What is the appropriate torque?

Answer 20

1 cm proximal to the eyebrows and tip of ears
Anterior placement at the equator (widest point) at the lateral 1/3 of the eyebrow
Posterior placement 1-2 cm posterior to the ear, directly opposition anterior pins
Torque 6-8 lb/in

Question 21

What is the function of a dorsal/palmar bar?

Answer 21

Maintain the palmar arch

Question 22

What is the function of the opponens bar?

Answer 22

Maintain the thumb in opposition, terminates just proximal to the MP joint

Question 23

What is the function of the thumb adduction stop?

Answer 23

Maintains the web space; terminates just proximal to the IP joint

Question 24

When is a thumb post indicated?

Answer 24

Flail thumb; it needs to extend beyond the nail bed but leave thumb pad free

Question 25

What is a mallet finger?

Answer 25

Occurs with a extensor tendon rupture; characterized by persistent flexion of the DIP joint

Question 26

What is a boutineer deformity?

Answer 26

Flexion of the PIP joint with hyperextension at the DIP

Question 27

What is a swanneck deformity?

Answer 27

Hyperextension of the PIP joint with flexion of the DIP; indicative of volar plate deficiency

Question 28

What does a positive Froment's sign indicate?

Answer 28

Ulnar nerve palsy

Question 29

What happens when someone with median nerve palsy is asked to make a fist?

Answer 29

Ape hand

Question 30

What occurs with radial nerve palsy?

Answer 30

Loss of wrist extension and MP extension

Question 31

Describe De Quervain's tenosynovitis

Answer 31

Tested for using Finklestein's test; symptoms include Pain near the base of your thumb Swelling near the base of your thumb Difficulty moving your thumb and wrist when you're doing something that involves grasping or pinching A "sticking" or "stop-and-go" sensation in your thumb when moving it

Question 32

What nerve is compressed with carpal tunnel syndrome?

Answer 32

Median

Question 33

What nerve is super painful when you hit your "funny bone"?

Answer 33

Ulnar

Question 34

What palsy would result in a benediction sign if you asked them to open their hand? Note: this is sometimes called "claw" or "ulnar claw"

Answer 34

Ulnar

Question 35

Where are the ground reaction forces at initial contact?

Answer 35

Anterior hip Anterior knee Posterior ankle

Question 36

Where are the ground reaction forces at loading response?

Answer 36

Posterior hip Posterior knee Posterior ankle

Question 37

Where are the ground reaction forces at mid stance?

Answer 37

Posterior hip Anterior knee Anterior ankle

Question 38

Where are the ground reaction forces at terminal stance?

Answer 38

Posterior hip Anterior knee Anterior ankle

Question 39

Where are the ground reaction forces at pre-swing?

Answer 39

Posterior hip Posterior knee Anterior ankle

Question 40

In Guillian-Barre syndrome, in what order does weakness occur? In what order does strength recover?

Answer 40

Onset: distal to proximal Recovery: proximal to distal

Question 41

Describe cauda equina

Answer 41

Comprises nerve roots below the spinal cord

Question 42

What is the most common congenital spinal deformity?

Answer 42

Spina bifida

Question 43

Describe alignment which would best promote stability in bilateral KAFOs

Answer 43

Fixed dorsiflexion, locked knee, hip in hyperextension

Question 44

When are the hip extensors most active?

Answer 44

Loading response

Question 45

Flaccid paralysis is most commonly seen in what type of motor nerve injury?

Answer 45

Lower motor nerve

Question 46

What compartment does the tibial nerve innervate? What gait deviation would you anticipate with a tibial nerve lesion?

Answer 46

Posterior | Plantarflexion contracture

Question 47

What position of the glenohumeral joint prevents subluxation?

Answer 47

Internal rotation, abduction