Nature of Movement Flashcards
Balance and Alignment
Correct body alignment reduces strain on musculoskeletal structures, aids in
maintaining adequate muscle tone, promotes comfort, and contributes to
balance and conservation of energy. Without balance control the center of
gravity is displaced. Individuals require balance for maintaining a static
position (e.g., siing) and moving (e.g., walking). Disease, injury, pain,
physical development (e.g., age), and life changes (e.g., pregnancy)
compromise the ability to remain balanced. Medications that cause dizziness
and prolonged immobility affect balance. Impaired balance is a major threat to
mobility and physical safety and contributes to a fear of falling and selfimposed
activity restrictions
Gravity and Friction
Weight is the force exerted on a body by gravity. The force of weight is always
directed downward, which is why an unbalanced object falls. Unsteady
patients fall if their center of gravity becomes unbalanced because of the
gravitational pull on their weight. Patients who are at risk for being unsteady
require the use of safe patient-handling techniques.
Friction is a force that occurs in a direction to oppose movement. The greater
the surface area of the object that is moved, the greater the friction. A larger
object produces greater resistance to movement. In addition, the force exerted
against the skin while the skin remains stationary and the bony structures
move is called shear. Unfortunately a common example is when the head of a
hospital bed is elevated beyond 60 degrees and gravity pulls a patient so that
the bony skeleton moves toward the foot of the bed while the skin remains
against the sheets. The blood vessels in the underlying tissue are stretched and
damaged, resulting in impeded blood flow to the deep tissues. Ultimately
pressure injuries often develop within the undermined tissue; the surface tissue
appears less affected. To decrease surface area and reduce
friction when patients are unable to assist with moving up in bed, use
ergonomic assistive devices such as a full-body hydraulic lift.
Nervous System
The nervous system regulates movement and posture. The precentral gyrus, or
motor strip, is the major voluntary motor area and is in the cerebral cortex. A
majority of motor fibers descend from the motor strip and cross at the level of
the medulla. Movement is impaired by disorders that alter neurotransmier
production, transfer of impulses from the nerve to the muscle, or activation of
muscle activity.
Ligaments, Tendons, and Cartilage
Ligaments are white shiny, flexible bands of fibrous tissue that bind joints
together, connect bones and cartilages, and aid joint flexibility and support.
Tendons are white, glistening, fibrous bands of tissue that connect muscle to
bone and are strong, flexible, and inelastic. Cartilage is nonvascular (without
blood vessels) supporting connective tissue located chiefly in the joints and
thorax, trachea, larynx, nose, and ear (see Chapter 38). The characteristics of the
cartilage change with the aging process.
Joints
The region where two or more bones attach is referred to as a joint.
Ligaments, Tendons, and Cartilage
Ligaments are white shiny, flexible bands of fibrous tissue that bind joints
together, connect bones and cartilages, and aid joint flexibility and support.
Tendons are white, glistening, fibrous bands of tissue that connect muscle to bone and are strong, flexible, and inelastic. Cartilage is nonvascular (without
blood vessels) supporting connective tissue located chiefly in the joints and
thorax, trachea, larynx, nose, and ear (see Chapter 38). The characteristics of the
cartilage change with the aging process.
Nervous System
The nervous system regulates movement and posture. The precentral gyrus, or motor strip, is the major voluntary motor area and is in the cerebral cortex. A majority of motor fibers descend from the motor strip and cross at the level of the medulla. Movement is impaired by disorders that alter neurotransmitter
production, transfer of impulses from the nerve to the muscle, or activation of muscle activity.
Postural Abnormalities
Congenital or acquired postural abnormalities affect the efficiency of the musculoskeletal system and body alignment, balance, and appearance.
Postural abnormalities can cause pain, impair alignment or mobility, or both.
Abnormalities page 2769
Muscle Abnormalities
Diseases lead to numerous alterations in musculoskeletal function. For example, the muscular dystrophies are a group of familial disorders that cause degeneration of skeletal muscle fibers. They are the most prevalent of the muscle diseases in childhood. Patients with muscular dystrophy experience
progressive, symmetrical weakness and wasting of skeletal muscle groups,
with increasing disability and deformity.
Damage to the Central Nervous System
Damage to any component of the central nervous system that regulates
voluntary movement results in impaired body alignment, balance, and
mobility. Trauma from a head injury, ischemia from a stroke (cerebrovascular
accident [CVA]), or bacterial infection such as meningitis can damage the
cerebellum or the motor strip in the cerebral cortex. Damage to the cerebellum
causes problems with balance, and motor impairment is directly related to the
amount of destruction of the motor strip. For example, a person with a rightsided
cerebral hemorrhage with necrosis has destruction of the right motor
strip that results in left-sided hemiplegia. Trauma to the spinal cord also
impairs mobility. For example, a complete transection of the spinal cord results
in a bilateral loss of voluntary motor control below the level of the trauma
because motor fibers are cut. Neurodegenerative disorders also have a negative
impact on mobility. For example, symptoms of Parkinson’s disease may
include rigidity, tremors, and postural instability (Shin et al., 2017).
Direct Trauma to the Musculoskeletal System
Direct trauma to the musculoskeletal system results in bruises, contusions,
tears, sprains, and fractures. A fracture is a disruption of bone tissue
continuity. Fractures most commonly result from direct external trauma, but
they also occur as a consequence of some deformity of the bone (e.g.,
pathological fractures of osteoporosis, Paget’s disease, metastatic cancer, or
osteogenesis imperfecta). Young children are usually able to form new bone
more easily than adults and, as a result, have few complications after a
fracture. Treatment often includes positioning the fractured bone in proper
alignment and immobilizing it to promote healing and restore function. Even
this temporary immobilization results in some muscle atrophy loss of muscle
tone, and joint stiffness.
Joint Disease
Osteoarthritis, loss of the articular cartilage, is the most common
noninflammatory arthritis, while rheumatoid arthritis is an example of a
noninfectious inflammatory arthritis (McCance and Huether, 2017). In the
acute care seing, nurses may care for patients with a variety of conditions
who also have a history of joint disease. In addition, nurses care for medical or
surgical admissions related to a specific joint disorder. An example of this is
the patient admied for a total joint replacement.
