Page 2101 - Saunders Comprehensive Review For NCLEX-RN

acetylcholinesterase.
e. Calcium is required for muscle fiber
contraction and acts as a catalyst for
the enzyme needed for the sliding-
together action of actin and myosin.
f. Following contraction, adenosine
triphosphate transports calcium out to
allow actin and myosin to separate and
allow the muscle to relax.
3. Skeletal muscles
a. Skeletal muscles are attached to 2 bones
by cartilaginous tendons called
enthuses (the connective tissue between
tendon or ligament and bone).
b. The point of origin is the point of
attachment that does not move.
c. The point of insertion is the point of
attachment that moves when the
muscle contracts.
d. Skeletal muscles act in groups.
e. Prime movers contract to produce
movement.
f. Antagonists relax.
g. Synergists contract to stabilize body
movement.
h. Nerves activate and control the
muscles.

E. Bone healing

1. Description: Bone union or healing is the process that
occurs after the integrity of a bone is interrupted.
2. Stages (Fig. 60-1)
II. Risk Factors Associated with Musculoskeletal Problems: See Box 60-1 for
more information
III. Diagnostic Tests
A. Radiography and magnetic resonance imaging (MRI) (refer to
Chapter 58 for information on MRI)
1. Description: Radiography and MRI are commonly
used procedures to diagnose problems of the
musculoskeletal system.

2. Interventions

a. Handle injured areas carefully and
support extremities above and below
the joint.
b. Administer analgesics as prescribed
before the procedure, particularly if

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