3.1 Musculoskeletal

Which combination correctly matches a bone constituent with its primary contribution to bone properties?

• Collagen — confers hardness and rigidity

• Calcium and phosphate — embed in collagen to confer hardness and rigidity

• Osteocytes — build new bone matrix

• Osteoclasts — are mature bone cells

Which statement best distinguishes compact bone from spongy bone?

• Compact bone contains many marrow-filled spaces; spongy bone is densely organized

• Compact bone is arranged in an organized fashion; spongy bone contains many marrow-filled spaces

• Compact bone is only found at the ends of long bones; spongy bone lines the medullary cavity

• Compact bone houses yellow marrow; spongy bone houses red marrow only in flat bones

Damage to which structure during growth can prevent a bone from reaching its mature length?

• Periosteum

• Epiphyseal plate (growth plate)

• Medullary cavity

• Articular cartilage

Which statement accurately describes the role of ligaments and synovial fluid in freely moving joints?

• Ligaments lubricate the joint, and synovial fluid holds articulating bones together

• Ligaments hold articulating bones together and provide strength, while synovial fluid lubricates the joint

• Synovial fluid strengthens ligaments, while ligaments cushion bones

• Ligaments attach muscle to bone, while synovial fluid nourishes tendons only

A patient presents with weakness in voluntary movement of the limbs due to impaired nerve stimulation at the myoneural junction. Which muscle type and connection are primarily involved?

• Smooth muscle connected to bones by ligaments

• Cardiac muscle connected to bones by tendons

• Skeletal muscle connected to bones by tendons

• Smooth muscle connected to bones by tendons

Which diagnostic test measures the electrical activity of muscles to help evaluate neuromuscular function?

• X-ray

• Magnetic resonance imaging (MRI)

• Arthroscopy

• Electromyography (EMG)

A patient with bone pain, fever, and leukocytosis after trauma is suspected of having an uncommon bacterial infection of bone. Which diagnosis best fits these signs and history?

• Osteoporosis

• Osteomyelitis

• Paget's disease

• Osteogenic sarcoma

Which scenario best illustrates the pathophysiology of osteoporosis as described?

• Bone formation outpaces bone resorption leading to enlarged skull and nerve compression

• Bone resorption exceeds bone formation resulting in porous, fragile bones prone to compression fractures

• Bacterial spread from lungs to bones affecting ends of long bones and vertebrae

• Soft, deformed bones in early childhood due to inadequate vitamin D

An adult presents with back fatigue, difficulty breathing from severe spinal curvature, and X-ray confirms an exaggerated posterior curve of the thoracic spine. Which condition is most likely?

• Scoliosis

• Kyphosis

• Osteomalacia

• Rickets

Which sign is most indicative of an open (compound) fracture rather than a closed fracture?

• Intense pain without visible deformity

• Swelling and bruising only

• Broken skin with protruding bone

• Numbness and tingling without skin damage