participate in bone remodeling by assisting in the breakdown of bone tissue.
the removal of old bone by osteoclasts (resorption) and the deposition of new bone by osteoblasts (ossification).
three types of cartilage
Hyaline cartilage: the most common, contains a moderate amount of collagen fibers. Found in the trachea, bronchi, nose, epiphyseal plate, articular surfaces of bones
Elastic cartilage: contains both collagen and elastic fibers, is more flexible than hyaline cartilage. Found in ear, epiglottis, larynx.
Fibrous cartilage (fibrocartilage): consist mostly of collagen fibers, tough tissue that often functions as a shock absorber. Found between vertebral discs; forms protective cushion between bones of pelvic girdle, knee, shoulder.
layers of connective tissue with intermeshed fibers that can withstand limited stretching.
small sacs of connective tissue lined with synovial membrane and containing viscous synovial fluid.
awareness of self in relation to the environment
Genetic Risk to Musculoskeletal Disorders
involves human leukocyte antigens (HLAs)
systemic lupus erythematosus
Osteoporosis: influence bone mineral density, bone size, quality and turnover.
Osteoarthritis, Gout, and Scoliosis:
Muscular Dystrophy: most common types are X-linked recessive disorders.
Performed on the supine patient with sciatica or leg pain
Passively raise patients leg 60 degrees or less.
Positive: pt. complains of pain along distribution of sciatic nerve.
Positive: indicates nerve root irritation from intervertebral disc prolapse and herniation, particularly at the level of L4-5 or L5-S1
Aspiration of fluid from a joint through a needle. [G. arthron, joint + G. kentesis, puncture]
Assessment Abnormalities: Achilles tendonitis
Description: Pain in posterior leg, initially when running or walking. Can progress to pain at rest.
Possible etiology and significance: Cumulative stress on Achilles tendon resulting in inflammation.
Assessment Abnormalities: ataxic gait
Description: Staggering, uncoordinated gait often with sway.
Possible etiology and significance: Neurogenic disorders (e.g., spinal cord lesion).
Assessment Abnormalities: atrophy
Description: Flabby appearance of muscle leading to decreased function and tone.
Possible etiology and significance: Muscle denervation, contracture, prolonged disuse as a result of immobilization.
Assessment Abnormalities: contracture
Description: Resistance of movement of muscle or joint as a result of fibrosis of supporting soft tissues.
Possible etiology and significance: Shortening of muscle or ligaments, tightness of soft tissue, incorrect positioning of immobilized extremity.
Assessment Abnormalities: ganglion cyst
Description: Small fluid-filled bump or mass over a tendon sheath or joint, usually on dorsal surface of wrist or foot.
Possible etiology and significance: Inflammation of tissues around a joint, which can increase in size or disappear.
Assessment Abnormalities: muscle spasticity
Description: Increased muscle tone (rigidity) with sustained muscle contractions (spasms); stiffness or tightness may interfere with gait, movement, speech.
Possible etiology and significance: Neuromuscular disorders such as multiple sclerosis (MS) or cerebral palsy.
Assessment Abnormalities: myalgia
Description: General muscle tenderness and pain
Possible etiology and significance: Chronic rheumatic syndromes (e.g., fibromyalgia). Overuse, injury, or strain.
Assessment Abnormalities: plantar fasciitis
Description: Burning, sharp pain on sole of foot; worse in the morning.
Possible etiology and significance: Chronic degenerative/reparative cycle resulting in inflammation.
Assessment Abnormalities: scoliosis
Description: Asymmetric elevation of shoulders, scapulae, and iliac crests with lateral spine curvature.
Possible etiology and significance: Idiopathic or congenital condition, fracture of dislocation, osteomalacia.
Description and Purpose: Assesses presence of autoantibody (rheumatoid factor) in serum. Factor is not specific for rheumatoid arthritis and is seen in other connective tissue diseases and in a small percentage of normal population.
Reference interval: Negative or titer <1:17
Does not require fasting.
Diagnostic Study: Markers of Muscle Injury: creatine kinase (CK)
Description and Purpose: Highest concentration found in skeletal muscle. Increased levels found in progressive muscular dystrophy, polymyositis, and traumatic injuries.
Male: 20-200 U/L
Female: 20-180 U/L
Does not require fasting.
Diagnostic Study: Markers of Muscle Injury: potassium
Description and Purpose: Increased in muscle trauma as cell destruction releases this electrolyte into serum. Cardiac dysrhythmias can be caused by hyperkalemia or hypokalemia
Diagnostic Study: Markers of Muscle Injury: aldolase
Description and Purpose: Useful in monitoring muscular dystrophy and dermatomyositis [A progressive condition characterized by symmetric proximal muscular weakness with elevated muscle enzyme levels and a rash, typically a purplish-red or heliotrope erythema on the face, and edema of the eyelids and periorbital tissue; affected muscle tissue shows degeneration of fibers with a chronic inflammatory reaction; occurs in children and adults, and in the latter may be associated with visceral cancer. [dermato- + G. mys, muscle, + -itis, inflammation]].