The Musculoskeletal System Quiz

The Musculoskeletal System

• Comprises of soft tissue (muscles, tendons, ligaments) and bones & joints
• Bone anatomy:
  • Long bones (e.g., femur, humerus)
  • Epiphyseal growth plate (active during adolescence)
• Bone healing process involves several stages:
  • Hematoma formation: a framework for healing created by fibrin and platelets
  • Procallus formation: fibro- and osteoblasts build granulation tissue (procallus)
  • Callus formation: procallus hardens with calcium and phosphate deposition
  • Replacement: callus replaced by lamellar or trabecular bone
  • Remodeling: bone remodeled to its pre-injury shape and size

Types of Joints

• Fibrous joints: bones directly connected by fibers (no movement)
• Cartilaginous joints: bones connected through cartilage (shock absorption and limited movement)
• Synovial joints: bones connected via synovial membrane (most movement)

Soft tissue

• Ligament: connects bone to bone
• Tendon: connects muscle to bone
• Muscle types
  • Skeletal muscle (voluntary, striated)
  • Smooth muscle (involuntary, non-striated)

Osteoporosis

• A condition causing bone weakness leading to fractures
• Potential causes:
  • decreased estrogen and testosterone
  • sedentary lifestyle
  • inadequate vitamin D and calcium intake
  • certain medications (e.g., steroids)
• Clinical manifestations:
  • pain
  • bone deformities
  • fractures
  • kyphosis (spinal curvature)
  • diminishing height
• Prevention:
  • Regular weight-bearing exercise
  • Sufficient calcium and vitamin D intake during adolescence
• Treatment:
  • SERMs, bisphosphonates, denosumab, teriparatide

Osteomyelitis

• Bone infection primarily caused by Staphylococcus aureus
• Can occur from:
  • external penetrating wound
  • existing infection
  • sepsis (bloodstream infection)
• Spreads under the periosteum and along the bone shaft or marrow
• Clinical manifestations:
  • Localized inflammation (pain, redness, loss of function, increased temperature)
  • Systemic symptoms (fever, elevated white blood cell count)
  • Necrotic bone tissue visible on imaging
• Treatment:
  • Surgical debridement and antibiotics

Osteoarthritis

• Also known as degenerative joint disease
• Age-related disorder affecting synovial joints
• Characterized by:
  • Cartilage loss in the joint
  • Bone sclerosis
  • Bone spur formation
• Clinical manifestations:
  • Pain, stiffness, enlargement, deformity, limited mobility of affected joint
  • Joint swelling (Herberden and Bouchard nodes)
  • Localized symptoms; no systemic manifestations

Ankylosing Spondylitis

• Chronic autoimmune inflammatory disease affecting the spine or sacroiliac joints
• Associated with HLA-B27 (human leukocyte antigen)
• Causes stiffening and fusion of the joints (ankylosis)
• Primarily affects the axial skeleton (spine)
• Clinical manifestations:
  • Low back pain, stiffness, restricted motion
  • Loss of lumbar curvature ("bamboo spine")
  • Kyphosis (outward curvature of cervical spine)
  • Chest pain/restricted chest movement
  • Fibrotic changes to organs
• Treatment:
  • Supportive therapy (physical therapy, occupational therapy)
  • Support groups
  • Non-steroidal anti-inflammatory drugs, pain medications
  • Local steroid injections to affected joints

Gouty Arthritis

• Metabolic disorder caused by high uric acid concentrations
  • Overproduction or inability to excrete uric acid
  • Uric acid is a product of purine metabolism, obtained from body or diet
  • Uric acid excreted through urine or stool
• Build-up of uric acid leads to crystallization and deposition in tissues
  • Causes acute joint pain and inflammation
  • Can deposit in cartilage, tendons, soft tissues (tophi - visible nodules)
• Other signs & symptoms:
  • Typically affects the big toe
  • Pain worse at night
  • Recurrent attacks of the same joint
• Treatment:
  • Weight reduction
  • Dietary changes (avoiding alcohol, shellfish, high-purine foods)
  • Pharmaceuticals

Pediatric Issues

• Scoliosis:
  • Caused by vertebral rotation (spinal curvature)
  • Treatment depends on the severity:
    • Bracing: for curvature between 25-40 degrees (prevents progression)
    • Surgery: for curvature greater than 40-50 degrees
• Bowing fracture:
  • Occurs primarily in children (due to thinner cortex in bones allowing for elasticity)
  • Mechanism: falling on outstretched hand, causing radial and ulnar bowing fractures
  • No visible fracture on x-ray but bone is bent

Test your knowledge on the musculoskeletal system, including bone anatomy, the healing process, and types of joints. This quiz covers essential concepts such as long bones, joint types, and the stages of bone healing. Perfect for students in anatomy or related health fields!