Musculoskeletal System
The musculoskeletal system consists of:
o the body's bones
o joints
o muscles.
Humans need this system (1) for support to stand erect, and (2) for movement.
The musculoskeletal system also functions (3) to encase and protect the inner
vital organs (e.g., brain, spinal cord, heart); (4) to produce the red blood cells,
white blood cells, and platelets in the bone marrow (hematopoiesis); and (5) as
a reservoir for storage of essential minerals such as calcium and phosphorus in
the bones.
The skeleton is the bony framework of the body.
It has 206 bones, which support the body like the posts and beams of a
building.
Bone and cartilage are specialized forms of connective tissue.
Bone is hard, rigid, and very dense. Its cells are continually turning over and
remodeling. The joint (or articulation) is the place of union of two or more
bones. Joints are the functional units of the musculoskeletal system because
they permit the mobility needed for activities of daily living (ADLs).
Structure and Function
Components of musculoskeletal system:
In non-synovial joints:
Non-synovial joints: bones united by fibrous tissue or cartilage are:
• Immovable, e.g., sutures in skull
• Slightly movable, e.g., vertebrae
Synovial joints
• Move freely because bones separated and enclosed in joint cavity
• This cavity is filled with a lubricant, or synovial fluid. Just like grease on gears,
synovial fluid allows sliding of opposing surfaces, and this sliding permits
movement.
, • In synovial joints a layer of resilient cartilage covers the surface of opposing
bones. Cartilage is avascular; it receives nourishment from synovial fluid that
circulates during joint movement. It is a very stable connective tissue with a slow
cell turnover. It has a tough, firm consistency yet is flexible. This cartilage
cushions the bones and gives a smooth surface to facilitate movement.
• Muscles (Skeletal, Smooth, Cardiac)
• Temporomandibular joint
• Spine
• Shoulder
• Elbow
• Wrist and Carpals
• Hip
• Knee
• Ankle and Foot
Skeletal Muscles
Each skeletal muscle is composed of bundles of muscle fibers or
fasciculi. The skeletal muscle is attached to bone by a tendon—a
strong fibrous cord. Skeletal muscles produce the following
movements:
o Flexion: bending limb at joint
o Extension: straightening limb at joint
o Abduction : moving limb away from midline of body
o Adduction : moving limb toward midline of body
o Pronation: turning forearm so that palm is down
o Supination: turning forearm so that palm is up
o Circumduction: moving arm in circle around shoulder
o Inversion: moving sole of foot inward at ankle
o Eversion: moving sole of foot outward at ankle
o Rotation: moving head around central axis
o Protraction: moving body part forward, parallel to ground
o Retraction: moving body part backward, parallel to ground
o Elevation: raising a body part
, o Depression: lowering a body part
Subjective Data
Joint pain and loss of function are the most common musculoskeletal
concerns that prompt a person to seek care.
Rheumatoid arthritis (RA) involves symmetric joints; other musculoskeletal
illnesses involve isolated or unilateral joints.
RA pain is worse in the morning when arising; osteoarthritis is worse later in
the day; tendinitis is worse in the morning, improves during the day.
Movement increases most joint pain except in RA, in which movement
decreases pain.
Joint pain 10 to 14 days after an untreated strep throat suggests rheumatic
fever. Joint injury occurs from trauma or repetitive motion.
Decreased ROM may be caused by joint injury to cartilage or capsule or to
muscle contracture.
Inside knee injury can strain or rupture medial ligament; outside injury can
strain or rupture lateral ligament; abrupt twisting can injure anterior
cruciate ligament.
Pop may mean tear in ligament or fracture. With direct knee trauma, obtain
x-ray if the patient is unable to flex knee to 90 degrees or unable to bear
weight, if pain is experienced at fibula head or patella, or if patient is over
age 55 years.
Myalgia is usually felt as cramping or aching.
Viral illness often includes myalgia.
Weakness may involve musculoskeletal or neurologic systems.
Fracture causes sharp pain that increases with movement. Other bone pain
usually feels “dull” and “deep” and is unrelated to movement.
Functional assessment screens the safety of independent living, the need
for home health services, and quality of life.
Assess any self-care deficit.
A strict program of regular high-dose exercises increases bone strength and
reduces fracture risk
Review daily aspirin and NSAID schedule; screen for adverse effects such as
GI pain. Menopausal hormone therapy (estrogen) increases BMD and
reduces fracture rates, although benefits disappear in a few years once
hormones are discontinued.
The musculoskeletal system consists of:
o the body's bones
o joints
o muscles.
Humans need this system (1) for support to stand erect, and (2) for movement.
The musculoskeletal system also functions (3) to encase and protect the inner
vital organs (e.g., brain, spinal cord, heart); (4) to produce the red blood cells,
white blood cells, and platelets in the bone marrow (hematopoiesis); and (5) as
a reservoir for storage of essential minerals such as calcium and phosphorus in
the bones.
The skeleton is the bony framework of the body.
It has 206 bones, which support the body like the posts and beams of a
building.
Bone and cartilage are specialized forms of connective tissue.
Bone is hard, rigid, and very dense. Its cells are continually turning over and
remodeling. The joint (or articulation) is the place of union of two or more
bones. Joints are the functional units of the musculoskeletal system because
they permit the mobility needed for activities of daily living (ADLs).
Structure and Function
Components of musculoskeletal system:
In non-synovial joints:
Non-synovial joints: bones united by fibrous tissue or cartilage are:
• Immovable, e.g., sutures in skull
• Slightly movable, e.g., vertebrae
Synovial joints
• Move freely because bones separated and enclosed in joint cavity
• This cavity is filled with a lubricant, or synovial fluid. Just like grease on gears,
synovial fluid allows sliding of opposing surfaces, and this sliding permits
movement.
, • In synovial joints a layer of resilient cartilage covers the surface of opposing
bones. Cartilage is avascular; it receives nourishment from synovial fluid that
circulates during joint movement. It is a very stable connective tissue with a slow
cell turnover. It has a tough, firm consistency yet is flexible. This cartilage
cushions the bones and gives a smooth surface to facilitate movement.
• Muscles (Skeletal, Smooth, Cardiac)
• Temporomandibular joint
• Spine
• Shoulder
• Elbow
• Wrist and Carpals
• Hip
• Knee
• Ankle and Foot
Skeletal Muscles
Each skeletal muscle is composed of bundles of muscle fibers or
fasciculi. The skeletal muscle is attached to bone by a tendon—a
strong fibrous cord. Skeletal muscles produce the following
movements:
o Flexion: bending limb at joint
o Extension: straightening limb at joint
o Abduction : moving limb away from midline of body
o Adduction : moving limb toward midline of body
o Pronation: turning forearm so that palm is down
o Supination: turning forearm so that palm is up
o Circumduction: moving arm in circle around shoulder
o Inversion: moving sole of foot inward at ankle
o Eversion: moving sole of foot outward at ankle
o Rotation: moving head around central axis
o Protraction: moving body part forward, parallel to ground
o Retraction: moving body part backward, parallel to ground
o Elevation: raising a body part
, o Depression: lowering a body part
Subjective Data
Joint pain and loss of function are the most common musculoskeletal
concerns that prompt a person to seek care.
Rheumatoid arthritis (RA) involves symmetric joints; other musculoskeletal
illnesses involve isolated or unilateral joints.
RA pain is worse in the morning when arising; osteoarthritis is worse later in
the day; tendinitis is worse in the morning, improves during the day.
Movement increases most joint pain except in RA, in which movement
decreases pain.
Joint pain 10 to 14 days after an untreated strep throat suggests rheumatic
fever. Joint injury occurs from trauma or repetitive motion.
Decreased ROM may be caused by joint injury to cartilage or capsule or to
muscle contracture.
Inside knee injury can strain or rupture medial ligament; outside injury can
strain or rupture lateral ligament; abrupt twisting can injure anterior
cruciate ligament.
Pop may mean tear in ligament or fracture. With direct knee trauma, obtain
x-ray if the patient is unable to flex knee to 90 degrees or unable to bear
weight, if pain is experienced at fibula head or patella, or if patient is over
age 55 years.
Myalgia is usually felt as cramping or aching.
Viral illness often includes myalgia.
Weakness may involve musculoskeletal or neurologic systems.
Fracture causes sharp pain that increases with movement. Other bone pain
usually feels “dull” and “deep” and is unrelated to movement.
Functional assessment screens the safety of independent living, the need
for home health services, and quality of life.
Assess any self-care deficit.
A strict program of regular high-dose exercises increases bone strength and
reduces fracture risk
Review daily aspirin and NSAID schedule; screen for adverse effects such as
GI pain. Menopausal hormone therapy (estrogen) increases BMD and
reduces fracture rates, although benefits disappear in a few years once
hormones are discontinued.
