Pathophysiology II Project

Front

What do you see? :)

Back

Compressive failure of the metaphyseal cortex due to pliable pediatric bone

Answer explanation

A buckle fracture (torus fracture), typically occurs in children due to the compressive force on soft, pliable bone. The metaphyseal cortex buckles under pressure without a complete break, making it a stable and common injury in pediatric populations

Front

What caused this? :'( Options: Acute, high-impact trauma causes immediate and complete cortical bone disruption, Repetitive mechanical loading exceeds the bone’s ability to remodel, leading to microcracks and eventual cortical break, Vitamin D toxicity leads to excessive calcium deposition, weakening the bone, Sudden drop in estrogen levels causes rapid bone demineralization over days

Back

Repetitive mechanical loading exceeds the bone’s ability to remodel, leading to microcracks and eventual cortical break

Answer explanation

This is a hairline fracture! Repetitive mechanical loading exceeds the bone’s ability to remodel, leading to microcracks and eventual cortical break.

Front

What happened? Options: The bone is brittle due to under-mineralization, leading to a complete transverse fracture; The bone cortex on one side fails under tension while the opposite side bends due to increased flexibility; The epiphyseal plate has closed prematurely, leading to uneven bone stress distribution; A lack of osteoblast activity has caused thinning of the periosteum, resulting in bone bowing

Back

The bone cortex on one side fails under tension while the opposite side bends due to increased flexibility.

Answer explanation

This is a greenstick fracture! The bone cortex on one side fails under tension while the opposite side bends due to increased flexibility

Front

A 10-year-old boy presents with fever, localized pain, and swelling in his right tibia. His parents report he had a minor scrape on his leg a week ago. Exam: tenderness, warmth, and erythema. Labs: elevated WBC count and CRP. MRI: bone marrow edema. Most likely diagnosis?

Back

Acute osteomyelitis

Answer explanation

Preceding trauma or skin breach allows S. aureus infection, typically at the metaphysis of long bones (near the knee). Bone pain, fever, elevated inflammatory markers, and MRI abnormalities confirm acute osteomyelitis

Front

65-year-old woman has chronic knee pain that worsens with activity, improves with rest, and lasts <30 min upon waking. Exam: crepitus, DIP joint enlargement. X-ray: joint space narrowing, osteophytes. Diagnosis?

Back

Osteoarthritis

Answer explanation

Overused and Aging of the cushion between joints

Activity-related pain, crepitus, osteophytes, and joint space narrowing: osteoarthritis most likely.

Heberden’s nodes (DIP enlargement) are classic.

Bouchard’s nodes = PIP

Front

A 72-year-old woman sustains a wrist fracture after a minor fall. Loss of bone mass is confirmed by a DEXA T-score of -2.7. What is the underlying pathophysiology?

Back

Increased bone resorption and decreased bone formation

Answer explanation

This is a problem with bone strength and density! Bone fracture from a minor fall suggests osteoporosis.

Osteomalacia: impaired bone mineralization due to vit D def

Paget Disease: excessive bone turnover causes thick, weak, and deformed bones (disorganized)

Malignant plasma cell infiltration → Seen in multiple myeloma

Front

Which of the following spinal nerve roots contribute to the formation of the radial nerve? C3–C5, C5–T1, C6–T2, C7–T1

Back

C5–T1

Answer explanation

The radial nerve originates from the posterior cord of the brachial plexus, which receives contributions from C5 to T1

C3–C5 mainly contribute to the phrenic nerve, which controls the diaphragm

The other options are partially correct do not fully describe the correct nerve pathways.

Front

Erb’s palsy involves which part of the brachial plexus? Options: Upper roots of the brachial plexus (C5–C6), Lower roots of the brachial plexus (C7–T1), Posterior cord of the brachial plexus, Long thoracic nerve

Back

Upper roots of the brachial plexus (C5–C6)

Answer explanation

C5–C6 control the shoulder and upper arm muscles, so damage causes Erb’s palsy with the classic “waiter’s tip” position (arm adducted, internally rotated, extended, and pronated). C7–T1 damage leads to Klumpke’s palsy, affecting the hand muscles.

Front

Which of the following is most likely affected in an ulnar nerve injury at the elbow? Loss of sensation over the lateral forearm, Weakness in wrist extension, Atrophy of the hypothenar muscles, Inability to flex the elbow

Back

Atrophy of the hypothenar muscles

Answer explanation

Atrophy of the hypothenar muscles is associated with ulnar nerve dysfunction, as the ulnar nerve innervates these muscles.

Lateral forearm sensation is supplied by the musculocutaneous nerve, not the ulnar nerve.

Wrist extension is primarily controlled by the radial nerve.

Elbow flexion is mainly performed by the biceps muscle, which is innervated by the musculocutaneous nerve, not the ulnar nerve.

Front

Name the autoimmune disorder resulting from articular cartilage destruction and syndesmophyte formation, leading to spinal bony joint fusion.

Back

Ankylosing spondylitis

Answer explanation

Ankylosing spondylitis (Bamboo spine): chronic inflammatory disease that primarily affects the spine. It causes inflammation of the joints and ligaments in the spine, leading to pain, stiffness, and eventually, fusion of the vertebrae (bones) due to the fibrin deposits that develop mainly in the spine and SI joints.