Body Mechanics Flashcards
Objectives
- At the end of the class, the student will be able to
- Explain the importance of proper body mechanics
- Demonstrate appropriate body mechanics while performing treatment interventions during skill competency and laboratory practical testing
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Review the Terms (p70)
Recumbent
Lying down
“increase in one of the forward convexities”
Lordosis
“movement of the pelvis so that the ASIS move anteriorly or posteriorly”
Pelvic Tilt
Reasons for proper body mechanics
Safety
- Safety
- Conserve energy
- Reduce stress and strain on body structures
- Reduce personal injury
- Maintain balance
- Effective, efficient respiratory function
“Described as the use of one’s body to produce motion that is safe, energy conserving, and anatomically and physiologically efficient and maintains body balance and control.”
Body mechanics
Patients and therapy staff should breathe normally when performing physical activity
Avoid the Valsalva maneuver: when does it occur
- Occurs when the patient holds their breath and air is trapped in the thorax
- Increases intrathoracic pressure
- Can cause a rupture of a cerebral vessel or can cause a cerebral vascular accident
the force that pulls toward the center of the earth and affects all objects
Gravity
The act of rubbing one object against another
Friction
fyi
Gravity and friction add resistance to many activities associated with lifting, reaching, pushing, pulling and carrying objects
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A component of a mechanical lever, it may be the force arm or the resistance arm
When the weight arm is decreased a greater mechanical advantage is created
Lever arms
expression of the effectiveness of the force in turning a lever system
- When an object is held close, you use a short lever arm and will work more effectively because a lower torque is required
Torque
the point at which the mass of the body or object is centered (Center of Mass)
Center of gravity (COG)
the area on which an object rests and provides support for the object
Base of support:
an imaginary vertical line that passes through the center of gravity of an object
vertical gravity line
Lifting properly
It is important to position your center of gravity close to the objects center of gravity
Keeping the 2 centers of gravity close to one another will help reduce the torque required to move or carry objects
The center of gravity is where the mass of an object is concentrated (the heaviest portion)
Have you ever seen a therapist assist a patient out of a wheelchair when at least moderate assist is required?
Establishing your base of support and lowering your center of gravity will increase your stability for lifting
Lifting properly
Adjusting the base of support can be done in two ways:
- Anterior posterior stance: 1 foot forward of the other foot
- Medial lateral stance: Place feet further apart side-by-side
- This will assist you in maintaining your vertical gravity line within your base of support
Base of support
Alteration of center of gravity
- The center of gravity can be altered by reaching for an object or shifting your weight to one foot
- When you shift your center of gravity you may not be within your base of support and can lose your balance
- You must shift your base of support to maintain your balance
stability
Stability is increased by lowering your center of gravity
Lowering your center of gravity can be done by squatting, stooping or kneeling
Preparing to lift
Plan the activity mentally and physically
Break the movement down into a series of movements that will be required to perform the activity
Determine the patient’s weight by checking the medical record or asking the person their weight
With objects, estimate the weight by sliding, tilting or partially lifting it.
Ask yourself: Do I need to lift this?
Preparing to lift 2
With objects it might be helpful to rock an object to gain momentum
Patients and anyone else assisting should be instructed in their responsibilities and tasks before the activity is performed
Have them repeat instructions to confirm their level of understanding
Preparing to lift 3
All instructions should be brief and concise
Lead into the action by using phrases such as one…two…three
Be prepared at all times to anticipate unexpected events (patient may have been minimum assist before and becomes maximum assist on this current lift)
Safety of transfer 1
Make sure the patient is pre-positioned
Use mechanical devices or equipment if necessary (hoist, transfer board, cart)
Raise or lower the bed as necessary
Use gravity or momentum
Always have assistance available before you attempt to complete a transfer you cannot safely perform alone
Safety of transfer 2
Never bend and twist when lifting or reaching for an object
This causes stress and strain to muscles ligaments and articulations in the posterior area of the spine and trunk
Always stoop or squat if the object is below the level of your waist
If reaching above your head use a foot stool or ladder
Safety of transfer 3
- Be aware of your own physical abilities and limitations
- Perform activities within your limits
- If attempting activities that are outside of your limits or if you aren’t sure of this, ask for assistance
- Your primary goal is to perform the activity safely, efficiently and with minimal stress or strain
Lifting principles and techniques 1
- The position of the lumbar spine is important during lifting
- Stress can be caused by the posture or position a person uses, the weight or size of the object or the repetitiveness of the activity
- Stress also occurs due to poor physical condition of the structures of the lumbar spine and abdominal muscles or being in a sustained flexed lumbar position
Lifting principles and techniques 2
- Injuries can occur from a single act of lifting a heavy object, lifting improperly or repetitive lifting
- Most injuries to the low back are caused by cumulative episodes of microtrauma caused by repetitive lifting
lifting principles and techniques
To avoid injury:
Maintain good general body strength and flexibility
Maintain proper nutrition (are you hydrated?)
Get appropriate rest
What is the best resting position of the spine?
Always use good posture
Always use proper body mechanics
Faulty posture
Stressful living and work habits
Poor use of body mechanics
Repetitive microtrauma
Poor flexibility of muscles and ligaments of the back and trunk
Decline in general physical fitness
Improper lifting
Common causes of back problems
- The lumbar spine should be maintained in a neutral position
- The neutral position includes a lordosis in the lumbar spine
- This reduces stress on the major structures of the lumbar area
- When the lumbar spine is in a position of lordosis there will be a decrease tendency to bend forward at the waist during lifting
Proper posture
Proper posture
Flexion of hips and knees allow us a lower center of gravity and provides an effective position for muscles of the lower extremities to perform the lift
Isometric contraction of the abdominal muscles helps provide stability and decreases the load to the lumbar spine
Deep squat lift (p75-76)
Hips are below the level of the knees
Lifters feet straddling object
Maintain trunk in a vertical position
Lumbar spine remains in lordosis
Do we not consider what the abs are doing?
Lifting techniques
Lifting techniques 2
A half squat is performed, hips are above the level of the knees
Feet are positioned parallel to one another and remain behind the object
Trunk is maintained in a more vertical position and lumbar spine remains in lordosis
What about the abs?
*the text figures for deep and power look very similar. There are small noted differences.
Power lift (p75-76)
Lifting techniques
Knees are slightly flexed or fully extended
Feet either parallel to each other or straddle the object
The trunk is positioned either vertically or horizontally
Lumbar spine remains in lordosis
And the abs???
Straight leg lift (p75 & 77)
Lifting techniques
use for lifting light objects easily lifted with one hand
Face the object with body weight shifted onto the forward lower extremity
Weight-bearing lower extremities partially flexed at the hip and knee
Non-weight-bearing lower extremity is extended to counter balance the forward movement of the trunk
- One leg stance lift (p75 & 77)
Lifting techniques
Face the object with the feet anteriorposterior on each side of the object
Lower extremities are in a deep squat
Grasp the side of the object with extremities parallel or anterior-posterior to one another
The lift is started by flexor muscles of the upper extremities partially lifting the object
Lower extremities then raised the body with object to an upright position
Object should be held close to the body and lumbar spine maintained in normal of the lordosis
Traditional lift (p78)
Pushing pulling reaching and carrying
- The same principals used for lifting apply to pushing and pulling activities
- In a therapy department this could include moving a gurney, pushing or pulling a wheelchair, or moving equipment.
Pushing, pulling, reaching and carrying
- When possible use a crouch or semi-squat position to push or pull.
- Remember…. center of gravity near to the objects center of gravity to increase your stability
- when pushing and pulling things, force should be applied parallel to the surface over which the object is to be moved and in the line of movement desired.
Pushing, pulling, reaching, and carrying 2
- Consideration should be given on how to overcome the effects of inertia and friction in the influence of vector forces
- Inertia and friction are forces and slow or inhibit movement of an object
- Be prepared to use greater effort when beginning to push or pull as more force is required to move a stationary object
- Hello Physics!!! Ahh… the memories….
Reaching overhead
it is less strenuous if you can lower the object or raise your position
Why?
Posture and Body Control
Prevention of back and neck problems is important in the workplace
- Good posture, strength and flexibility are important factors
- Poor posture can cause prolonged tension on muscles or joints causing chronic muscle and joint strains
- Poor physical conditioning leads to loss of the strength and endurance
- Sustained posture can result in pain and fatigue
Posture and body control
Ideal alignment per plumb line assessment:
- Slightly anterior to the lateral malleolus
- Slightly anterior or through the knee
- Through the greater trochanter or
- Midway through the trunk
- Through the shoulder
- Through the bodies of the cervical vertebrae
- Through the lobe of the ear
Posture and body control
The posture that places minimal stress on the back is in sitting
Proper sitting posture includes a resting position for the upper extremities and an absence of a forward head posture
Lumbar support in sitting can improve posture
Posture and body control 4
Sustained standing causes postural fatigue and can worsen kyphosis
Correcting faulty posture is important for preventing __________?
injuries
Posture and body control
- Providing information on basic anatomy of the body can be important.
- Instruction in use of proper body mechanics and correcting faulty positions should occur during therapy
- Simple exercises including posterior pelvic tilt, knee to chest, partial sit-ups, hamstring stretches, hip extension stretch, press ups, wall slides and neck stretches can be helpful.
Posture and body control
Instruct patients in methods to protect or to relieve back stress
- Place 1 foot on a stool while standing
- Use of a lumbar cushion or role while sitting
- Proper positioning at a desk or table
- Frequent changes in positions that can reduce back stress or strain
- it might be important for the work or home environment to be evaluated
