Human Anatomy: Skeletal and Muscular Systems

Skeletal System Overview

• The skeletal system provides structure and protection.
• Bones serve as levers for movement.
• Bones store calcium.
• Bones produce blood cells (red marrow).
• The human body contains 206 bones.
• Red marrow produces blood cells; yellow marrow is composed of fat.

Muscular System

• The body has approximately 650 skeletal muscles.
• These muscles are voluntary and under conscious control.
• Skeletal muscles attach to bones via tendons.
• Muscles assist with posture, produce body heat, and allow movement.

Joints

• Joints are where two or more bones meet.
• Joints exhibit varying ranges of motion (ROM).
• Fibrous joints (e.g., skull sutures) are immovable.
• Cartilaginous joints (e.g., vertebral bodies) are slightly movable.
• Synovial joints (e.g., knee, shoulder) are freely movable.

Common Symptoms and Health History

• Common symptoms include joint pain and stiffness.
• Systemic symptoms associated with joint pain: fever, chills, rash, weakness, and weight loss.
• Other symptoms include low back pain, neck pain, bone pain, muscle pain or cramps, and muscle weakness.
• Extra-articular pain involves pain around the joint (bones, muscles, and tissues).
• Conditions like bursitis, tendinitis, and tenosynovitis fall under this category.

Physical Assessment

• Inspect joint symmetry, alignment, and bony deformities.
• Inspect and palpate surrounding tissues for changes (e.g., skin changes, nodules, muscle atrophy, crepitus).
• Test ROM actively (patient) and passively (examiner).
• Assess for inflammation (swelling, warmth, tenderness, redness).
• Assess muscle strength.
• Observe gait and posture (fall risk assessment).

ROM (Range of Motion) Descriptions

• Abduction: Movement away from the body's midline.
• Adduction: Movement toward the body's midline.
• Circumduction: Circular motion.
• Inversion: Movement inward.
• Eversion: Movement outward.
• Extension: Straightening at a joint, increasing the angle.
• Hyperextension: Joint bending greater than 180 degrees.
• Flexion: Bending at a joint, decreasing the angle.
• Dorsiflexion: Toes pulled up toward the ankle.
• Plantar flexion: Toes pointed away from the ankle.
• Supination: Palms up.
• Pronation: Palms down.

Muscle Evaluation

• Atrophy: Muscles shrink, become flat or concave.
• Tone:
  • Normal: Relaxed with slight residual tension.
  • Increased (hypertonia): Spasticity (muscle spasms) and rigidity (muscle stiffness).
  • Decreased (hypotonia): Flaccid (absence of muscle tone).
• Strength Grading (0-5):
  • 0: No contraction; paralysis.
  • 1: Trace or barely detectable contraction.
  • 2: Movement with gravity eliminated.
  • 3: Movement against gravity.
  • 4: Movement against gravity and some resistance.
  • 5: Movement against full resistance.

Specific Joint Assessments

• TMJ (Temporomandibular Joint): Inspect for swelling or redness. Facial asymmetry and jaw "clicking" are possible symptoms. Palpate in the joint during mouth opening.
• Shoulder: Inspect for swelling, deformities, and muscle atrophy. Inspect the upper extremity for color changes or skin alterations. Palpate bony landmarks. Assess SITS muscles (rotator cuff).
• Elbow: Inspect size, shape, and symmetry. Palpate the olecranon process and epicondyles. Assess for flexion, extension, pronation, and supination. Test for muscle strength.
• Carpal Tunnel: Inspect hand position, palpate for swelling, and assess for radial/ulnar deviation. Evaluate for numbness, tingling, and weakness.
• Wrist: Palpate distal radius and ulna. Assess for swelling and tenderness. Test for flexion, extension, radial/ulnar deviation. Test for muscle strength. Assess grip strength.
• Fingers and Thumb: Assess for flexion, extension, abduction, adduction, and opposition.
• Spine: Inspect posture, alignment, and the spinal curves (concave/convex). Palpate for tenderness or changes in the spinous processes.
• Hip: Inspect gait, symmetry, and ROM. Avoid ROM testing after hip replacement.
• Knee: Inspect gait, symmetry, and contour. Palpate the tibiofemoral joint. Assess ROM for flexion, extension, and rotation. Assess muscle strength.
• Ankle and Foot: Inspect for deformities, swelling, redness, calluses, and corns. Palpate the anterior aspect of the joint, Achilles tendon, and malleoli. Assess ROM (flexion, extension, inversion, eversion) and muscle strength.

Special Conditions

• Rheumatoid Arthritis: Autoimmune disorder; inflammation of joint lining. Characterized by morning stiffness, inflammation, pain, and joint deformity.
• Osteoarthritis: Overuse syndrome (DJD); characterized by joint pain and stiffness, usually after middle age, possible presence of nodes (Heberden and Bouchard).
• Fractures: Trauma, disease, or overuse can cause fractures. Splints, casting, or surgical repair may be required for treatment. Potential for fracture complications (e.g., fat embolism, compartment syndrome, VTE/PE, infection).
• Osteoporosis: Loss of bone mass, often associated with aging, but more common in postmenopausal women.. Calcium intake and weight-bearing exercise can help.

Additional Important Considerations

• Gait Assessment: A crucial element for assessing overall health and potential issues, focusing on the smooth rhythmic flow and symmetry of movement.
• Muscle Strength Assessment: Graded on a scale of 0-5, evaluating the strength and ability of muscles to resist movement against force.

Explore the fundamental aspects of the skeletal and muscular systems in the human body. This quiz covers the structure, function, and health implications of bones, joints, and muscles. Test your knowledge on how these systems support movement and overall health.