TNCC Musculoskeletal Trauma 2 — Questions and Answers
Question 1: A patient with a femur fracture develops sudden onset chest pain, hypoxia, and petechiae on the chest and axillae 48 hours post-injury. Which complication is most likely?
- Pulmonary embolism
- Fat embolism syndrome (Correct answer)
- Pneumothorax
- Cardiac contusion
Correct answer: Fat embolism syndrome
Fat embolism syndrome classically presents 24–72 hours after long bone fractures with the triad of hypoxemia, neurologic changes, and petechial rash on the upper body.
Question 2: When assessing a patient with a suspected pelvic fracture, which clinical sign indicates significant retroperitoneal hemorrhage?
- Cullen's sign
- Grey Turner's sign (Correct answer)
- Kehr's sign
- Rovsing's sign
Correct answer: Grey Turner's sign
Grey Turner's sign (flank ecchymosis) indicates retroperitoneal hemorrhage, which is a serious complication of pelvic fractures due to disruption of pelvic vasculature.
Question 3: A patient arrives after a crush injury to the lower extremity. Which serum lab value is the BEST early indicator of rhabdomyolysis?
- Serum creatinine
- Creatine kinase (CK) (Correct answer)
- Myoglobin
- Lactate dehydrogenase
Correct answer: Creatine kinase (CK)
CK is the most sensitive and specific marker for skeletal muscle damage, rising within 2–12 hours of injury and peaking at 24–72 hours.
Question 4: Which type of pelvic fracture is associated with the highest risk of life-threatening hemorrhage?
- Lateral compression fracture
- Vertical shear fracture
- Anterior-posterior compression fracture (Correct answer)
- Acetabular fracture
Correct answer: Anterior-posterior compression fracture
Anterior-posterior compression (open-book) fractures disrupt the pelvic ring and tear the posterior venous plexus and iliac vessels, causing massive hemorrhage.
Question 5: During reassessment, a patient with a tibial fracture reports worsening pain that is unresponsive to opioid analgesia and pain with passive stretch of the toes. What is the priority intervention?
- Elevate the limb above heart level
- Apply ice to reduce swelling
- Notify the physician immediately for compartment pressure measurement (Correct answer)
- Administer a higher dose of analgesic
Correct answer: Notify the physician immediately for compartment pressure measurement
Pain unrelieved by opioids and pain with passive stretch are hallmark signs of acute compartment syndrome requiring urgent pressure measurement and possible fasciotomy.
Question 6: A patient with an open femur fracture requires antibiotic prophylaxis. According to evidence-based guidelines, which antibiotic class should be administered first?
- Fluoroquinolones
- First-generation cephalosporins (Correct answer)
- Aminoglycosides
- Vancomycin
Correct answer: First-generation cephalosporins
First-generation cephalosporins (e.g., cefazolin) are the first-line prophylactic antibiotic for open fractures to reduce infection risk from gram-positive organisms.
Question 7: A patient sustained an elbow dislocation and now reports numbness and tingling in the ring and little fingers. Which nerve is most likely injured?
- Radial nerve
- Median nerve
- Ulnar nerve (Correct answer)
- Musculocutaneous nerve
Correct answer: Ulnar nerve
The ulnar nerve runs posterior to the medial epicondyle and is the most commonly injured nerve with elbow dislocations, causing numbness in the 4th and 5th digits.
TNCC Musculoskeletal Trauma 2
A patient with a femur fracture develops sudden onset chest pain, hypoxia, and petechiae on the chest and axillae 48 hours post-injury.
Which complication is most likely?