Orthopedics Question Bank

Read the Orthopedics Question Bank sample questions

1. 1.A 24-year-old man sustains a mid-shaft humeral fracture in a fall. On exam he cannot extend his wrist or fingers and has decreased sensation over the dorsal first web space. Which nerve is most likely injured?

   • A.Radial nerveCorrect
   • B.Median nerve
   • C.Ulnar nerve
   • D.Musculocutaneous nerve

   Why: The radial nerve runs in the spiral groove along the posterior humeral shaft and is the nerve most commonly injured with mid-shaft humeral fractures. Wrist drop with sensory loss over the dorsal first web space is the classic presentation. Most radial nerve palsies from closed fractures are neurapraxias that recover spontaneously.

2. 2.A 30-year-old woman falls on an outstretched hand and has isolated wrist pain. Radiographs show a fracture line through the waist of the scaphoid. Which factor most explains the high risk of avascular necrosis of the proximal pole?

   • A.Rich periosteal blood supply
   • B.Retrograde blood supply entering distallyCorrect
   • C.Abundant nutrient artery to the proximal pole
   • D.Extensive muscular attachments

   Why: The scaphoid receives its dominant blood supply from branches of the radial artery entering distally and dorsally, so flow to the proximal pole is retrograde. A proximal waist or proximal-pole fracture can therefore devascularize the proximal fragment, causing avascular necrosis and nonunion. This anatomy underlies the emphasis on early diagnosis and immobilization.

3. 3.A 6-year-old child has an extension-type supracondylar humerus fracture. The hand is pink and warm but the radial pulse is absent and capillary refill is 2 seconds. What is the most appropriate initial management?

   • A.Immediate exploration of the brachial artery
   • B.Observation with repeat exam in 24 hours
   • C.Urgent closed reduction and pinningCorrect
   • D.Apply a long-arm cast in full extension

   Why: A pink, perfused but pulseless hand is usually addressed by urgent closed reduction and percutaneous pinning, which frequently restores the pulse by relieving arterial kinking or tethering. Perfusion, not merely the palpable pulse, guides the need for vascular exploration. If the hand remains poorly perfused after reduction, then vascular exploration is indicated.

4. 4.A 40-year-old man has a comminuted radial head fracture involving the entire head with more than three fragments and a block to rotation. According to the Mason classification, which type is this?

   • A.Type I
   • B.Type II
   • C.Type IV
   • D.Type IIICorrect

   Why: Mason type III radial head fractures are comminuted fractures involving the entire head that are typically not amenable to fixation. Type I are nondisplaced, type II are displaced with a single fragment, and the modified Mason type IV describes a radial head fracture with an associated elbow dislocation. Comminuted type III injuries often require radial head replacement.

5. 5.A 55-year-old woman falls and sustains a distal radius fracture with the distal fragment dorsally displaced and dorsally angulated. This pattern is best described as which eponymous fracture?

   • A.Colles fractureCorrect
   • B.Smith fracture
   • C.Barton fracture
   • D.Chauffeur fracture

   Why: A Colles fracture is a distal radius fracture with dorsal displacement and dorsal angulation, classically from a fall on an outstretched hand producing a dinner-fork deformity. A Smith fracture is the volar-displaced reverse pattern. A Barton fracture is an intra-articular shear fracture and a chauffeur fracture involves the radial styloid.

6. 6.A 20-year-old man dislocates his shoulder anteriorly. Which nerve is most at risk, and what finding would confirm its injury?

   • A.Musculocutaneous nerve; weak elbow flexion
   • B.Axillary nerve; numbness over the lateral shoulderCorrect
   • C.Radial nerve; wrist drop
   • D.Long thoracic nerve; winged scapula

   Why: The axillary nerve wraps around the surgical neck of the humerus and is the nerve most commonly injured in anterior shoulder dislocation. Sensory testing over the lateral deltoid (regimental badge area) and deltoid motor function should be documented before and after reduction. Most axillary nerve injuries in this setting are transient neurapraxias.

7. 7.A 35-year-old man presents with a fracture of the proximal ulna and an associated dislocation of the radial head. What is this injury pattern called?

   • A.Galeazzi fracture-dislocation
   • B.Essex-Lopresti injury
   • C.Monteggia fracture-dislocationCorrect
   • D.Nightstick fracture

   Why: A Monteggia fracture-dislocation is a proximal ulna fracture with radial head dislocation. The direction of radial head dislocation follows the apex of the ulnar fracture angulation, as described by the Bado classification. In adults, anatomic reduction and stable fixation of the ulna are essential to reduce and maintain the radial head.

8. 8.A 45-year-old woman sustains a distal-third radial shaft fracture with disruption of the distal radioulnar joint. What is the eponym and the definitive adult treatment?

   • A.Monteggia; ulnar plating
   • B.Colles; closed reduction and casting
   • C.Nightstick; functional bracing
   • D.Galeazzi; open reduction and internal fixation of the radiusCorrect

   Why: A Galeazzi fracture is a distal radial shaft fracture with disruption of the distal radioulnar joint. In adults this is inherently unstable and requires open reduction and internal fixation of the radius, after which distal radioulnar joint stability is reassessed. Nonoperative treatment in adults has a high rate of loss of reduction and is not recommended.

9. 9.A 60-year-old man has a mid-shaft humeral fracture treated in a functional (Sarmiento) brace. Which is the most important reason this technique often succeeds?

   • A.Gravity and muscle compression align the fracture as motion is allowedCorrect
   • B.The humerus requires perfect anatomic alignment to heal
   • C.The shoulder must be immobilized in abduction
   • D.Rotational alignment is unimportant for upper limb function

   Why: Functional bracing of the humeral shaft relies on gravity-assisted alignment and soft-tissue compression while allowing motion at the shoulder and elbow. The humerus tolerates moderate angulation and shortening because of the mobility of the adjacent joints, so nonoperative treatment yields high union rates. Rigid immobilization is generally unnecessary for most closed humeral shaft fractures.

10. 10.A 28-year-old man with a forearm crush injury reports severe pain out of proportion to injury, worsening with passive finger extension, and a tense swollen forearm. What is the most appropriate next step?

    • A.Elevate the limb and reassess in the morning
    • B.Apply a tight compressive dressing
    • C.Obtain an MRI of the forearm
    • D.Measure compartment pressures or proceed to fasciotomyCorrect

    Why: Pain out of proportion to injury and pain with passive stretch are the earliest and most reliable signs of acute compartment syndrome. When clinical suspicion is high, urgent fasciotomy is indicated, and compartment pressure measurement can support the diagnosis when the exam is equivocal. Elevation and tight dressings can worsen perfusion and must be avoided.