P&O Flashcards
What is stride length?
Linear distance b/w corresponding successive points of contact of the same foot
What is step length?
Linear distance in plane of progression b/w corresponding successive contact points of opposite feet
How much time percent wise in gait cycle are you in stance vs. swing? What about double-limb vs. single-limb support in normal gait cycle?
60 stance, 40 swing;
20 double-limb vs 80 single-limb
Center of gravity typically located
5 cm anterior to the S2 vertebra
Subdivisions of stance phase?
- Initial contact (heel strike)
- Loading response (Foot flat); lowest COG
- Midstance (Midstance); highest COG
- Terminal stance (Heel off)
- Preswing (Toe off)
Subdivisions of swing phase?
- Initial swing (Acceleration)
- Midswing (Midswing)
- Terminal swing (Deceleration)
6 determinants of gait?
- Pelvic rotation
- Pelvic tilt
- Knee flexion in stance
- Foot mechanisms (ankle flexion/extension mechanisms)
- Knee mechanisms
- Lateral displacement of pelvis
When is iliopsoas active during gait cycle?
Concentric with terminal stance, preswing, initial swing, midswing
When is glute max active during gait cycle?
Initial stance, eccentric
When is glute med active during gait cycle?
Eccentric during initial stance, loading response, midstance, terminal stance
When are hamstrings active during gait cycle?
Eccentric during initial stance and loading response (similar to pretibial muscles); also during swing phase
When are quads active during gait cycle?
Eccentric during initial stance and loading; also during preswing and initial swing
When are pretibial muscles active during gait cycle?
Eccentric during initial stance and loading response; concentric during swing phase
When are calf muscles active during gait cycle?
Eccentric during mid stance;
concentric during terminal stance and pre-swing
What does excessive trunk lateral flexion b/w loading response and preswing suggest?
Ipsilateral glute med weakness (compensated Trendelenburg gait)
Primary disturbance in Parkinson’s gait? Other key features?
Reduced step length;
Stooped posture, festinating gait, shuffling, freezing, decreased arm swing
Consequences of hip flexion contracture on gait?
Increased anterior pelvic tilt, increased knee flexion, also increased energy consumption
Compared to ambulation in normal patients, those propelling WC showed ______ increase in energy expenditure
9%
Muscles needed for crutch walking?
UE:
Latissimus dorsi, triceps, pec major;
LE:
Quads, hip extensors, hip abductors
Major risk factor for LE amputations?
Diabetes
Leading cause of UE amputations?
Trauma
When to do amputation for mangled hand?
Irreparable damage to four of the following:
- Skin
- Vessels
- Skeleton
- Nerves
- Extensor tendons
- Flexor tendons
Percentile ranges for transradial amputation?
Very short: residual limb less than 35%;
Short: 35-55
Long: 55-90
Percentile ranges for transhumeral amputation?
Humeral neck: Residual limb less than 30%;
Short transhumeral: 30-50;
Standard transhumeral: 50-90
What is the most common and practical type of terminal device?
Body-powered voluntary opening device
In prosthetic wrist unit, what does wrist flexion unit allow with terminal device?
To be in flexed position, facilitating ability to perform activities close to the body. Important for b/l UE amputees
Two types of wrist units?
Friction wrists, locking wrists
What does transradial amputation prosthesis require?
- Harness and control system
- Upper arm cuff/pad
- Elbow hinge
- Socket
- Wrist unit
- Terminal device
What transradial prosthetic socket can be used with a figure-9 harness for control purposes?
Muenster socket
What is the most commonly used trans-radial harness?
Figure-8 (O-ring) harness
When is the single-control vs. dual-control cable system used?
Single-control for transradial single-control cable system;
Dual-control for transhumeral and very short transradial split-socket prosthesis
What is the harness used most frequently for transhumeral prostheses?
Modifications of the basic figure-8 and chest strap patterns used with transradial prostheses
How does the dual-control cable system operate?
One cable with two functions:
- Flex elbow unit when elbow is unlocked
- Operate terminal device when elbow locked
For body-powered vs myoelectric control systems, what are advantages to both?
Body-powered: less expensive, lighter, more durable, easier to repair, sensory feedback;
myoelectric: better cosmesis, stronger grasp force, less harnessing
For body-powered vs myoelectric control systems, what are disadvantages to both?
Body-powered: Mechanical appearance, depends on your motor strength, difficult to use;
Myoelectric: More expensive, heavier, decreased durability due to other components
Myoelectric transradial prostheses use _______ ______ to activate the prosthesis
muscle contractions
Most common causes of LE amputations per age group
0-5: congenital
5-15: Cancer, trauma
15-50: Trauma
Over 50: Vascular, infection
Define myodesis vs myoplasty?
Myodesis: Muscles and fasciae sutured directly to bone;
myoplasty: Opposing muscles sutured to each other and to periosteum