Unit 4: Musculoskeletal System

Musculoskeletal System

Most musculoskeletal system disorders are caused by the degeneration of tissue or damage to muscles or bone.

Skeletal System

Made up of over 200 different bones, which are stiff connective tissues in the human body. Bones ensure that our bodies have structure, allows movement, and protects internal organs. They are formed by immature cells called osteoblasts. As bone cells mature they become osteocytes. 

Bone marrow is responsible for the production of red blood cells and platelets

Function of bones:

• Protecting internal organs

• Synthesizing blood cells

• Storing necessary minerals

• Providing the muscular system with leverage to create movement

Joint: the point at which a bone is attached to another bone.

Tendons: connect muscle to bone

Various connective tissues join the parts of the skeleton together to other systems, including ligaments and cartilage.

Disease states that affect the skeletal system are arthritis, gout and osteoporosis.

Arthritis: inflammation in the joints of the body, damaged bone joints lead to arthritis. 

Gout: inflammation and pain in the joints caused by a uric acid imbalance within our bodies

Osteoporosis: causes bone tissue to wear away and makes bones weak and frail.This weakness increases a patient’s chance of obtaining a bone fracture; poor bone mineral density due to the loss or lack of production of calcium content in bone cells, which makes bones more likely to fracture

Arthritis

• Degenerative 

• Inflammation and pain in joints

• SX: swollen and red skin, limited joint movement, and joint pain

• Osteoarthritis – Large joint wear and tear

• Rheumatoid Arthritis (RA) - autoimmune disease that destroys connective tissue

Osteoarthritis

• Most common form of arthritis, usually presents in the hands, knees, hips, lower back and neck, however, can affect any joint.

• Can degrade cartilage, change bone shape and cause inflammation resulting in pain, stiffness and loss of mobility

• There is no cure so therapy is aimed at minimizing pain, continuing physical activities and maintaining a good quality of life.

Symptoms: pain, joint stiffness, limited range of motion, clicking/popping sound around the joint, muscle weakness around the joint, and joint instability.

Treatment of Osteoarthritis

Treatment includes pain and anti-inflammatory medications, which includes various dosage forms (pills, liquids, patches, creams, and injectables)

Analgesics: APAP and Opioids

NSAIDS: ASA, ibuprofen, naproxen, and celecoxib; when NSAIDS are dosed low you get pain coverage, however, you need the higher dose for inflammation coverage.

Cymbalta, Lyrica

Continuation of OA Treatment

Corticosteroids (CCS): prednisone (Deltasone)

• Decrease inflammation 

• Immunosuppressants

• Provide fast, relief

• Short amount of usage time, 3 months  or less

SE: -adrenal insufficiency

      -Increases in blood sugar which can lead to permanent diabetes

      -Bone loss, bone death

      -Weight gain

      -Increased risk of cataracts and glaucoma

      -High Blood Pressure

      -Infections

      -Mood changes

      -skin changes

Counseling: Take with Food

Topical OTC Product to Treat Arthritis

Capsaicin comes from cayenne peppers; warms the skin and blocks the chemical in the nerve cells that sends pain signals to the brain. 

• Examples include Capzasin-HP  (0.1%) and Zostrix (0.025%)

• Capsaicin works best if used several times a day. It might take up to two weeks to feel relief.

• Wear gloves when applying, make sure to wash your hands thoroughly after application

• Salicylates are what relieve pain in aspirin. 

  • Topical treatments include Aspercreme 

• Counterirritants These make the skin feel hot or cold. Those feelings might block pain signals. 

  • Counterirritants might contain menthol or camphor. 

  • Examples include Icy Hot, Biofreeze, and Tiger Balm

• Anesthetics Topical anesthetics cause numbness, which blocks transmission of nerve messages (pain)

  • Ex)  Lidocaine comes in a cream, gel, spray or patch. 

  • Examples include LidoPatch (lidocaine 3.6% and menthol 1.25%) and Icy Hot Max (Lidocaine 4% and menthol 1%)
    

Rheumatoid Arthritis

• Inflammatory, autoimmune condition  where the body’s immune system mistakenly attacks its own body tissues. In RA the lining of the joints is attacked and results in a chronic inflammatory disorder of the joints but can also affect other organs.

• The synovium produces a liquid to help the joint move smoothly. In RA the inflamed synovium gets thicker and makes the joint area feel painful, tender, red, swollen, and painful to move the joint.

• Most cases are symmetrical  (affect both sides of the body) and normally begin with the small joints, affecting the hands, knees, and ankles.

• Symptoms: joint pain longer than 6 weeks, morning stiffness 30 minutes or longer and affects more than one joint on both sides of the body

• There is no cure for RA; goal is to treat early and aggressively to decrease or stop inflammation leading to clinical remission. 

• To treat RA many drugs must turn off the immune system, which makes the body 

 susceptible to infections, cancer, and other diseases

Treatment of RA

NSAIDs 

Corticosteroids: prednisone (Deltasone)

Conventional Disease-Modifying Antirheumatic Drugs (DMARDs)

-Slow disease progression-tries to save joints and tissues from permanent damage

-Each DMARD works differently

-They suppress the immune system to control the inflammation, however, this can lead to increasing the risk of infections

-Side effects limit use (HA, nausea, rash, infection)

BW: Risk of infections (ALL DMARDS)

-all DMARDS require close monitoring, blood tests, and xrays

• Biologic DMARDS: genetically engineered proteins that target specific parts of the immune system that causes increases in inflammation; only available as an injection or IV 

  • Humira, Enbrel and Remicade: decrease the signs and symptoms of moderate to severe RA by reducing joint swelling, pain, fatigue, and morning stiffness.

    BW: serious infections and malignancy

    SE: infections (notify MD of fever, fatigue, cough, or red and painful skin)

    DI: do not use with other biologics; cannot receive live vaccines

    –Need a negative TB test to initiate therapy

    Humira and Enbrel are SQ injectables 

    Remicade is delivered by IV infusion

• Janus Kinase Inhibitors (JAK Inhibitors): block the enzymes janus kinase 1,2, or 3 that signal inflammation and immune responses seen in RA

  • Xeljanz: oral Janus Kinase (JAK) inhibitor, blocks the enzymes responsible for sending inflammatory signals in the body; treats moderate to severe RA

    BW: serious infections, increase risk of death and major CV events, cancer, blood clots in the lungs

    SE: N/V, HA, nasal congestion, diarrhea, upper respiratory infections, ↑ cholesterol levels

    -Need a negative TB test to initiate therapy

    -given by mouth

• Hydroxychloroquine:relatively safe medication to treat mild RA.  

SE: Nausea, diarrhea

• Sulfasalazine: lessens pain/swelling and slows progression of RA

SE: N/V; yellow-orange urine or skin

**DMARDS require close monitoring, blood tests, x rays

Biologics

Biologics are medications that come from organic life. Scientists produce biologic medications by removing organic proteins or genetic materials from cellular lifeforms and, when possible, reproducing them. This means scientists might have to clone genes that reproduce the proteins they need. Or they might implant altered DNA into a living cell and then reproduce it through the cell on a large scale.

Biologic medications are an example of biotechnology. That’s when scientists use biology (the study of living things) to develop new products and technology to address human problems. Biologic drugs (biopharmaceuticals) often treat difficult diseases that traditional human-made drugs can’t successfully treat. But biologics are also much more complicated and expensive to make than synthetic drugs are.

Biosimilars:

• A biosimilar and its original biologic are made from the same types of sources – and have the same treatment risks and benefits.

• Biosimilars are a type of biologic medication that is safe and effective for treating many illnesses.

• A biosimilar and its original biologic have the same treatment risks and benefits.

• Biosimilars may be available at a lower cost than the original biologic

Gouty Arthritis

• Sudden, severe attacks of pain, swelling, redness, and tenderness in one or more joints. These attacks can come and go.

• Caused by accumulation of urate crystals in the joint which lead to inflammation and intense pain due to improper production,decreased  kidney excretion of uric acid and diet

• Big toe is usually the first joint affected, may also present in the ankles and knees

• GA peak after 12-14 hours and slowly go away on their own; Resolves in 3-10 days with treatment

• Inherited, more common in men

What to Avoid:

• Diuretics

• Alcohol

• Aspirin

• Niacin

• Red meat

• Organ meats

• Sugary sodas

Treatment of Gout

• NSAIDs (indomethacin most common)

• Corticosteroids (if one cannot tolerate NSAIDs)

• Colchicine

• Allopurinol

• Febuxostat

Muscular System

Primary function is movement:  muscle contracts and relaxes,  resulting in motion.  

3 Types of Muscle:

1. Cardiac Muscle: only found in the heart.  Heart contracts involuntarily, creating the heartbeat and pumping of blood.

2. Visceral (smooth) Muscle:  tissue found in many of the body’s essential organs including the stomach and intestines.  It contracts involuntarily to move nutrients, blood, and other substances throughout the body.

3. Skeletal Muscle:  responsible for voluntary movement and linked to the skeletal system

Osteoporosis

• Poor bone mineral density due to the loss or lack or production of calcium content in bone cells, which makes bones more likely to fracture.

• Deficiency in estrogen, calcium, and vitamin D

• Reduction of bone production which leads to decreased bone mass

• Occurs in at a faster rate > 50 years old

• Risk factors include gender, heredity, age

• Risk increased with alcohol consumption and smoking

Treatment of Osteoporosis

• Weight bearing exercise

• Calcium

• Vitamin D

• Bisphosphonates

• Selective Estrogen Receptor Modulator

• Estrogen

Bisphosphonates

• Increases bone density

• Can be prescribed to patients to treat and prevent osteoarthritis

• SE: headache, upset stomach, musculoskeletal pain, irritation of the esophagus, nausea, diarrhea

• DI: calcium supplements and antacids (decrease absorption of bisphosphonate) 

• Take at least 30 minutes before first meal of day with 6-8 ounces of water. 

• Remain upright for 30 minutes

• Reclast given via IV route every 1 to 2 years depending on usage

• Actonel and Fosamax typically dosed once a weekly
  

Selective Estrogen Receptor Modulator: Safer to use  than estrogen in patients who have contraindication to estrogen

Muscle Spasms

Muscle cramps: involuntary muscle contractions (spasms) that cause intense pain.

• A muscle spasm is a sudden and involuntary contraction of one or more muscles.

• Can result from: muscle overexertion; pain; fatigue

• Limbs and spine are most often involved

• Acute Spasms: result of muscle injury or overuse

• Chronic Spasms: result from prolonged injury or underlying medical condition

• Muscle Relaxant: a drug that reduces or prevents skeletal muscle contraction and spasms and provides pain relief. Also used to reduce spasticity in multiple sclerosis, cerebral palsy and skeletal muscle injuries.

Muscle Relaxers

• Not specific to injured muscle

• SE: drowsiness, dizziness, sedation, decreased mental alertness, decreased motor abilities; GI upset

• DI: CNS Depressants and alcohol (can lead to increased sedation and respiratory depression)

• Do not operate heavy machinery