Body Mechanics

What are body mechanics?

Protecting your body while doing various activities and holding positions as you stand, lift, carry, and bend

What is the purpose of body mechanics?

• Conserve energy

• Reduces stress and strain on body structures

• Reduce the risk of personal injury

• This leads to safe movements of the spine

• Promotes and maintains proper body control and balance

• Promotes effective and efficient respiratory and cardiopulmonary function

What are the principles of proper body mechanics?

Size up a load, determine which lift to use, mentally and physically prepare, increase your BOS, position the body closer to the object, tighten core muscles, roll, push, pull or slide object, take your time

What is the Valsa maneuver?

• When someone holds their breath while doing something strenuous

• Dec venous blood flow to the heart

• Inc intrathoracic pressure

• Dec cardiac output

• Inc BP

• Cerebral vessel could rupture

What is COG?

• In the center of the pelvis and anterior to the second sacral segment

• For an object it’s the point at which it is the heaviest

• Positioning a person’s COG closer to an object closer to a COG makes the object easier to move (less torque required)

What is line of gravity (LOG)?

An imaginary line that bisects the body in the sagittal plane

What are causes of potential injuries?

• Lumbar spine is the most vulnerable

• Sensitive structures: ligaments, lumbodorsal fascia, annulus fibrosus of the intervertebral disk, vertebral facets, nerve roots, muscle tissue, vertebral body

• Means of injury: act of lifting, lifting improperly, repetitive lifting, cumulative micro trauma

• Avoid: simultaneous trunk flexion and twisting

What is a deep squat lift?

• Half-squat so hips above knees

• Feet parallel and behind the object

• Arms parallel

• Grasp objects on opposite sides

• Maintain a vertical trunk and lumbar spine in lordosis with anterior pelvic tilt

What is a straight leg lift?

• Knees slightly bent or straight

• Legs parallel

• Arm parallel

• Grasp objects on opposite sides

• Trunk vertical or horizontal

• Lumbar spine remains in lordosis (inward curvature)

What is a one-leg stance lift?

• Used to lift light objects

• Face object

• Feet facing forward

• Weight shifted to one leg

• Partially flex hip and knee on weight-bearing leg

• Extend non-weight bearing leg

• Lift the object as if picking up a golf ball from a tee

What is a half-kneeling lift?

• Kneel on one knee, position behind and on one side of the object

• Position the other leg with the foot flat with both hip and knee flexed at 90 degrees

• Place object on thigh of the flexed leg

• Move the object close to the body

• Begin rising to standing position

• Maintain normal lordosis

What is a traditional lift?

• Face the object with feet facing forward

• Grasp the object underneath with arms parallel

• Contract flexors of the elbow and shoulders

• Contract extensors of the legs

• Hold the object close to the body

• Maintain normal lordosis of the lumbar spine

What is a stoop lift?

• Partially flex hips and knees

• Maintain normal lordosis of the lumbar spine

• Grasp object with hands

• Use legs to raise body and object, keeping the object close to the body

What to do when pushing, pulling, reaching, and carrying?

• Use a crouched or semi-squat position to push/pull

• Appy force parallel to the supporting surface

• Exerts more force at the beginning of the push/pull