Musculoskeletal, Skin, and Connective Tissue- Anatomy and Physiology (2)

Question 1

Iliotibial band syndrome

Answer 1

Overuse injury of lateral knee that occurs primarily in runners. Pain develops 2° to friction of iliotibial band against lateral femoral epicondyle.

Question 2

Medial tibial stress syndrome (shin splints)

Answer 2

Common cause of shin pain and diffuse tenderness in runners and military recruits.

Caused by bone resorption that outpaces bone formation in tibial cortex

Question 3

Limb compartment syndrome

- Definition

Answer 3

Increase pressure within a fascial compartment of a limb (defined by compartment pressure to diastolic
blood pressure gradient of < 30 mm Hg) Ž venous outflow obstruction and arteriolar collapse Ž anoxia and necrosis.

Question 4

Limb compartment syndrome

• Etiology
• Presentation

Answer 4

Causes include significant long bone fractures, reperfusion injury, animal venoms.

Presents with severe pain and tense, swollen compartments with limb flexion. Motor deficits are late sign of irreversible muscle and nerve damage

Question 5

Plantar fasciitis

Answer 5

Inflammation of plantar aponeurosis characterized by heel pain (worse with first steps in the morning or after period of inactivity) and tenderness

Question 6

De Quervain tenosynovitis

Answer 6

Noninflammatory thickening of abductor pollicis longus and extensor pollicis brevis tendons characterized by pain or tenderness at radial styloid.

⊕ Finkelstein test

Question 7

Ganglion cyst

Answer 7

Fluid-filled swelling overlying joint or tendon sheath, most commonly at dorsal side of wrist. Arises from herniation of dense connective tissue.

Question 8

Developmental dysplasia of the hip

Answer 8

Abnormal acetabulum development in newborns. Results in hip instability/dislocation.

Commonly tested with Ortolani and Barlow maneuvers. Confirmed via ultrasound

Question 9

Legg-Calvé-Perthes disease

Answer 9

Idiopathic avascular necrosis of femoral head.

Commonly presents between 5–7 years with insidious onset of hip pain that may cause child to limp. More common in males (4:1 ratio). Initial x-ray often normal.

Question 10

Slipped capital femoral epiphysis

Answer 10

Classically presents in an obese ~12-year-old child with hip/knee pain and altered gait.

Increased axial force on femoral head Ž epiphysis displaces relative to femoral neck.

Diagnosed via x-ray. Treatment: surgery.

Question 11

Osgood-Schlatter disease (traction apophysitis)

Answer 11

Overuse injury caused by repetitive strain and chronic avulsion of the secondary ossification center of proximal tibial tubercle.

Occurs in adolescents after growth spurt. Common in running and jumping athletes. Presents with progressive anterior knee pain.

Question 12

Radial head subluxation (nursemaid’s elbow)

Answer 12

Common elbow injury in children < 5 years.

Caused by a sudden pull on the arm Ž immature annular ligament slips over head of radius. Injured arm held in flexed and pronated position.

Question 13

Types of muscle fibers

- Type 1 muscle

Answer 13

Slow twitch; red fibers resulting from High mitochondria and myoglobin concentration (High oxidative phosphorylation) Ž sustained contraction

Question 14

Types of muscle fibers

- Type 2 muscle

Answer 14

Fast twitch; white fibers resulting from Low mitochondria and myoglobin concentration

Question 15

Endochondral ossification

Answer 15

Bones of axial skeleton, appendicular skeleton, and base of skull.

*Defective in achondroplasia

Question 16

Membranous ossification

Answer 16

Bones of calvarium, facial bones, and clavicle