chap 12

• Musculoskeletal system includes muscles, tendons, and ligaments that attach to the bone and joints and rely on the nervous and endocrine system
• Human skeleton has 206 bones
• Skeleton not only gives structure but also stores minerals and helps muscles move
• Calcium is essential for bone strength, and its levels are regulated by hormones like calcitonin and parathyroid hormone
• Thyroid produces calcitonin, which allows calcium to remain in the bone and not move into the blood
• Parathyroid secretes Parathyroid hormone, which increases the amount of calcium in the blood and leads to the loss of calcium in the bones
• Calcium assists with muscle contraction and nerve pulses
• Meds used to treat muscular disorders include Cyclobenzaprine (Flexeril), antispasmodics like Metaxalone (Skelaxin), and sometimes benzodiazepines like Diazepam (Valium)
• Newer drugs like Duloxetine (Cymbalta) are used for chronic back pain
• Botulinum toxin type A (Botox) can be used to relax muscles by blocking acetylcholine and is also helpful for migraines, limb spasticity, abnormal head position, neck pain, underarm sweat, and certain eye muscle problems
• Myasthenia Gravis is an autoimmune disease that causes fatigue and weakness due to the loss of acetylcholine receptors, treated with Cholinesterase inhibitors like Neostigmine
• Fibromyalgia is characterized by chronic pain in muscles and soft tissues surrounding joints, treated with physical therapy, antidepressants, anti-inflammatory meds, trigger point therapy, and narcotics
• Abnormal calcium levels can lead to conditions like Osteomalacia in adults, Rickets in children, and Osteoporosis, which is caused by a lack of calcium and vitamin D
• Paget's disease enlarges bones excessively, making them weak and fragile, treated with calcitonin, bisphosphonates, calcium, and vitamin D
• Arthritis and gout can cause inflammation of the bone and joints
• Osteoarthritis is erosion of bone where the bone and joint meet, affecting middle-aged or older people, or those who are active or inactive
• Rheumatoid arthritis is an autoimmune condition affecting joints, treated with nonsteroidal anti-inflammatory drugs (NSAIDs)
• Gout is caused by a buildup of uric acid in the joints, treated with NSAIDs, colchicine, and antigout medications like Allopurinol or Febuxostat
• Various medications like COX-2 inhibitors, disease-modifying antirheumatic drugs (DMARDs), and glucocorticosteroids are used to manage arthritis and related conditions
• Musculoskeletal System:

  • Consists of muscles, tendons, ligaments (attach muscle to bones), and 206 bones
  • Nervous system controls movement
  • Bones provide structure and store minerals like calcium, magnesium, and potassium
• Endocrine system:

  • Thyroid produces calcitonin, allowing calcium to remain in bone
  • Parathyroid gland produces parathyroid hormone, increasing calcium in the blood (loss of calcium in bones)
• Muscular Disorders:

  • Ailments originating in the brain: cerebral palsy, stroke, multiple sclerosis
  • Ailments originating in muscle tissue: muscle injuries, muscular dystrophy
• Medications for Muscular Disorders:

  • Muscle symptoms: muscle spasms, dystonia (abnormal tension)
  • Treatments: muscle relaxants like cyclobenzaprine (Flexeril), antispasmodics like metaxalone (Skelaxin) to inhibit neurological activity causing spasms or rigidity
  • Benzodiazepines (Valium) may be given to enhance effectiveness of above medications
• Myasthenia Gravis:

  • Progressive autoimmune disease causing skeletal muscle fatigue and weakness
  • Treatment: cholinesterase inhibitors like neostigmine to facilitate acetylcholine accumulation
• Fibromyalgia:

  • Disorder of chronic pain in muscles and soft tissue surrounding joints
  • Treatment includes decreasing contributory factors, physical therapy, antidepressants, anti-inflammatory medications, trigger point injections, and narcotic analgesics
• Abnormal Calcium Levels:

  • Hypocalcemia (low blood calcium) risk factors include smoking, lack of exercise, high alcohol consumption, etc.
  • Osteomalacia in adults and rickets in children result from low calcium levels
  • Osteoporosis occurs with lack of calcium, leading to bone holes and easy fractures
  • Treatment involves vitamin D for absorption, calcium supplements, estrogen replacement therapy, and medications like Fosamax
• Paget’s Disease:

  • Chronic disease enlarging bones, resorbing bone excessively
  • Treatment includes calcitonin, bisphosphonates, calcium, and vitamin D supplements
• Medications for Bone and Joint Inflammation:

  • Osteoarthritis: erosion of bone at joints, treated with NSAIDs
  • Rheumatoid arthritis: autoimmune condition affecting joints, treated with DMARDs like gold aurothioglucose, Rheumatrex, Neoral, and Azulfidine
• Gout:

  • Form of arthritis from uric acid build-up in joints
  • Treatment during acute attack includes NSAIDs, colchicine, glucocorticoids; after attack, anti-gout medications like allopurinol or febuxostat are used
• Nonsteroidal Anti-Inflammatory Drugs (NSAIDs):

  • Reduce inflammation but have concerns like GI bleeding, renal, and cardiac damage
  • Aspirin and other analgesics used topically and orally for pain relief
• Cyclooxygenase-2 (COX-2) Inhibitors:

  • Technically NSAIDs, decrease prostaglandin production causing pain and inflammation
  • May increase heart problem risks, contraindicated in sulfa drug allergy
• Disease-Modifying Anti-Rheumatic Drugs (DMARDs):

  • Used in rheumatoid arthritis when other drugs are ineffective
  • Suppress autoimmune response and immunity systemically, may slow joint destruction
  • Examples include gold aurothioglucose, Rheumatrex, Neoral, and Azulfidine
• Corticosteroids:

  • Mimic cortisol to reduce inflammation, used short-term due to decreased infection-fighting ability
• Medications for Phantom Limb Pain:

  • Impulses from brain and spinal cord not recognizing limb absence
  • Treatment includes tricyclic antidepressants, anticonvulsants, and narcotics to manage pain