Midterm Exam Review

____ amputations are 11x more common than ____

LE>UE

The leading cause of amputation is ________

Dyvascular disease

What are the risk factors for amputations as a consequence of disease?

• CCVD

• HTN

• High cholesterol

• Smoking

Amputations due to trauma are most common among which population?

Young adult men

Amputations due to cancer are most common in ages ____

12-20

Amputations due to cancer are most often a result of ___________

Osteosarcoma

The “name” of the amputation is always based on…

 The main bone amputated or the joint disarticulated

T/F: Most amputations occur proximally

FALSE

What are the 4 main categories of surgical consideraitions for an amputation?

1. Nerves [pulled distally to avoid neuromas in scar tissue]

2. Bone

3. Healing

4. Post-op dressing

Smokers have a ____ rate of infections and re-amputation

2.5x

What is the MOST important factor that can affect rehab success?

The activity level AT (before) the time of amputation

______ preservation is key for ambulation success

Knee

Main risk factors for diabetic foot:

1. Sensory loss

2. Abnormal mechanical stresses

3. Poor circulation

What are the areas tested in the Semmes-Westein Monofilament testing?

• 1,3,5 Met heads

• Medial & lateral midfoot

• Heel

____ = BEST # for protective sensation assessment

5.07

Vascular risk factors:

• Ankle Brachial Index < 0.9

• Toe systolic pressure < 30mmHg

• Transcutaneous oxygen tension < 26 mm/Hg

Prevention risk categories:

• 0 = No loss of protective sensation

• 1 = Loss of protective sensation

• 2 = Loss of protective sensation with high pressure (callus/deformity) or poor circulation

• 3 = PMHx of ulceration

Follow up schedule based on prevention (0-3):

1. Education; 6 mo F/U for foot/shoe screening; protective footwear; nail/callus/skin care as needed

2. Education; molded/modified footwear; 3 mo F/U for foot/shoe screening; protective footwear; nail/callus/skin care as needed

3. Education; monthly F/U for foot/shoe screening; appropriated footwear; nail/callus/skin care as needed

An ABI of <.45 means…

Wound healing is unlikley

When is an amputation necessary?

Presence of necrosis because of vascular impairment or trauma (with or without infection)

What are the 3 main factors that determine the level of amputation?

1. Ability to heal at the incision

2. Removal of nonviable tissues

3. Ability to achieve a long-term functional residual limb (to avoid revisions)

During the post-op stage, dressings are worn for about _________

2 weeks

During the post-op stage, after removing dressings, patients get for a preparatory prosthesis that they will wear for ________

3-12 months during the residual limb shrinkage (this is NOT standard practice anymore)

The standard length of a transtibial amputation (measured from tibial plateau) is ____

5-6 inches

If the residual limb is ______, pt will have difficulty with prosthetic control

3 in or less

For a TT circumference residual limb measurement, you should start at _________________

Tibial plateau or tibial tuberosity

For a TF circumference residual limb measurement, you should start at _________________

Ischial tuberosity or greater trochanter

Desired shape of residual limb: TT vs TF

• TT: Cylindrical shape — within ¼ inch of the proximal circumference

• TF: Conical shape — distal should be less than proximal

ACE Wraps: Pros and Cons

• Disadvantages: Requires skill and experience for proper application

  • Can slip and form a tourniquet effect

• Advantages: Inexpensive, Light Weight, Readily Available

Shrinkers: Pros and Cons

• Advantages: Easy to don, no special skill needed to don, easy to control amount of pressure

  • Pressure is constant

• Disadvantages: More expensive than ace wrap, often painful to apply and wear immediately after surgery

IPOP: Pros and Cons

• Advantages: Immediate ambulation with limited weight bearing (will be connected to prosthetic foot!)

  • ↓ psychological traumatic period when limb is absent

  • Less pain, mobilize faster,

• Disadvantages: Possibly injurious effects, particularly in weight bearing and its effects on wound healing

  • Limits access to the surgical site, potential tissue damage and wound breakdown

RRD: Pros and Cons

• Advantages: Provides excellent protection, improved wound healing environment (not connected to prosthetic foot)

  • Allows some weight-bearing exercises

• Disadvantages: Does not prevent flexion contractures

  • Messy and requires skill/practice

What are the TWO essential things that determine when a patient is ready for their prosthetic?

When the wound is healed (#1), and when the best shape for the residual limb is achieved

Main forms of contractures:

• TT: Knee flexion

•  TF: Hip flexion, abduction, and external rotation (bad for ambulation)

Delaying weight bearing at least ______ may reduce complications

2 weeks

Functional demands of the foot during the stance phase:

1. Shock absorption

2. Maintain balance during single limb support

3. Propulsion

____ of all partial foot amputees ultimately require revision to a higher amputation level 

1/3

Standard treatment for a transphalyngeal amputation

Diabetic shoe

Standard treatment for a ray resection amputation

Toe filler

Resection of the _____ ray is most common due to ulceration

5th

Transverse Metatarsal Amputation (TMA): Main complications

1. Balance and gait are affected: ↓ WB area, ↓ lever arm

2. Muscle imbalances: DF is often limited due to the loss of attachment points for the DF muscles

3. Skin breakdown and ulcer due to sheer friction and pointed pressure

For a TMA, why is the risk of EV+PF contracture so high?

PF is unopposed by DF since attachment points were removed (Some DF are also inverters, which follow this same relationship)

What is a Lisfranc amputation? What are the main complications?

• Tarsal-metatarsal disarticulation

  • Same risks as TMA + Higher risk for plantar flexion contracture

Which type of amputation has the HIGHEST risk for PF ccontracture?

Chopart (mid-tarsal disarticulation)

What is a Chopart amputation? What are the main complications?

• MID-tarsal disarticulation

  • Talo-navicular + Cuneiform-calcaneus disarticulation

  • Same concerns as Lisfranc and TMA + Highest risk of contracture

Functional deficits with Midfoot PFA

• ↓ lever arm & ↓ step length (with sound leg)

Shoe fillers should allow toe break/extension by ___ degrees

15

Ss the length of the foot decreases, there is a greater need for additional _______ control

Proximal

What is a Boyd amputation? What are the advantages?

• Horizontal resection of calcaneus followed by arthrodesis to distal tibia

• Allows end weight bearing without a prosthesis

What is a Pirogoff amputation? What are the advantages?

• Vertical resection of calcaneus rotated 90 degrees then arthrodesis to distal tibia

• Allows end weight bearing without a prosthesis

What is a Symes amputation? What are the PROS and CONS?

Ankle disarticulation

• Pros

  • Self-suspension over malleoli

  • Maintains limb length + clearance

  • End weight bearing within socket

• Cons

  • Bulbous distal end → limited suspension and prosthetic foot options

  • Requires a healthy calcaneal fat pad

  • Requires application of volume management socks.

Identify K Level: Does not have the ability or potential to ambulate or transfer safely

K0

Identify K Level: Has the ability or potential to use a prosthesis for transfer or ambulation on level surfaces at constant cadence

K1

Identify K Level: Has the ability or potential for ambulation with the ability to traverse low level environmental barriers such as curbs, stairs, or uneven surfaces

K2

Identify K Level: Has the ability or potential for ambulation for ambulation with variable cadence

K3

Has the ability or potential for prosthetic ambulation that exceeds basic ambulation skills, exhibiting high impact, stress or energy levels

K4

When does insurance cover a lower limb prosthesis?

If pt will reach or maintain a defined functional state within a reasonable period of time

SACH contraindications

• When inversion/eversion is required

• K3-K4 patients (active individuals)

  • Disadvantages: Limited plantar flexion/dorsiflexion adjustability

Flexible Keel contraindications

• When inversion/eversion is required

• K3-K4 patients (active individuals)

What are the main indications for a single axis foot prescription?

• Need for ↑ knee stability (controls compression)

  • Very short TT residual limb

  • Hip disarticulation

  • Patients whose knees “buckle” – as this induces knee EXTENSION moment

Single axis foot contraindications

• When inversion/eversion is required

• K3-K4 patients (active individuals)

What are the main indications for a Multiaxial foot prescription?

• Ambulation on varying terrain

  • ↑ knee stability at heel strike, bumpers can be varied

  • simulates inversion/eversion AND reduces torque on residual limb

    • K2???

What are the main indications for a dynamic response foot prescription?

• Variable cadence** (K3-K4)

• Ambulators + unlimited community ambulators

  • Active individuals (NOT FOR K2-1)

What are the main indications for a multiaxial dynamic response foot prescription?

• Variable cadence** (K3-K4)

• Ambulators + unlimited community ambulators

  • Suitable for uneven terrain

  • Active individuals (NOT FOR K2-1)

Why would you use a knee immobilizer over a RRD or any other dressings?

Prevents Flexion Contracture + Protection & Compression

What are the most pressure-sensitive areas in a PTB socket?

Tibial tuberosity, fibular head, and hamstring tendons

After ___ ply socks, the pateint will need a new socket

10

In a PTB-SC, the prostheris ssuspends from the _______

Femoral condyles

What are the main advantages of a PTB-SCSP socket?

• Controls Knee extension using the Quadriceps Bar

  • Good for those that tend to hyperextend

  • Good for those with short residual limbs

What are the main advantages of a TSB socket?

• Equal distribution of loads across the entire surface of the residual limb

• Improved Suspension

• Decreased shear on the residual limb

Anatomical suspensions are mainly prescribed for which population?

Pediatric patients and disarticulation amputees

Suction suspensions are contrainidicated when…

excessive volume fluctuations or inability to complete donning

Suspension sleeve advantages

Allow unrestricted knee motion but does control for rotational component

A supracondylar cuff mainly restricts knee ______ and does NOT provide _____ stability

flexion, M/L

Which suspension mechanism provides the MAXIMAL M/L stability as well as prevention of recurvatum?

Thigh corset

• Redistributes some weight-bearing and torque forces to the thigh

A supracondylar cuff mechanism does not provide even suspension through ________ _______

Swing phase

AMPnoPRO scoring

(Out of 43)

• K0 = 0-8

• K1 = 9-20

• K2 = 21-28

• K3 = 29-36

• K4 = 37-43

AMPro Scoring

(Out of 47)

• K1 = 15-26

• K2 = 27-36

• K3 = 37-42

• K4 = 43-47

TT bilateral amputation patients have _______ energy expenditure than TF unilateral amputation patients

LESS, remember the importance of the knee joint in energy preservation!

Traumatic TT bilateral amputees experience a _____ increase in EE

41%

Traumatic TF unilateral amputees experience a _____ increase in EE

60-70%

Quiet standing is “a natural stance is achieved when the ______ is balanced with the _______ at the foot.”

CoG, CoP

Plumbline alignment

• Hip – slightly ________

• Knee – slightly _______

• Ankle – slightly _______

• Hip – slightly POSTERIOR (EXT moment)

• Knee – slightly ANTERIOR (EXT moment)

• Ankle – slightly ANTERIOR (DF moment)