OTC Orthopaedic Technologist 4 — Questions and Answers
Question 1: Which bone is most commonly fractured in the wrist and is at high risk for avascular necrosis due to its blood supply?
- Lunate
- Scaphoid (Correct answer)
- Trapezium
- Hamate
Correct answer: Scaphoid
The scaphoid is the most commonly fractured carpal bone and receives most of its blood supply distally, making proximal pole fractures prone to avascular necrosis.
Question 2: What is the primary purpose of bivalving a cast?
- To allow the cast to dry faster
- To relieve pressure and accommodate swelling (Correct answer)
- To convert a short cast to a long cast
- To strengthen the structural integrity
Correct answer: To relieve pressure and accommodate swelling
Bivalving (splitting the cast longitudinally on two sides) relieves circumferential pressure, accommodating acute swelling and reducing the risk of compartment syndrome.
Question 3: A patient with a hip fracture placed in Buck's skin traction should have the weight limited to what maximum?
- 2–5 lbs (Correct answer)
- 5–10 lbs
- 10–15 lbs
- 15–20 lbs
Correct answer: 2–5 lbs
Buck's traction uses skin adhesives or foam boot and is limited to 2–5 lbs (1–2 kg) to prevent skin breakdown and circulatory compromise.
Question 4: Which assessment tool using the mnemonic '6 Ps' is used to evaluate neurovascular status of an extremity in a cast?
- Pain, Pallor, Pulselessness, Paresthesia, Paralysis, Pressure (Correct answer)
- Pulse, Pressure, Position, Pain, Pallor, Paresthesia
- Pain, Pulse, Pressure, Pallor, Pulselessness, Paralysis
- Pallor, Paresthesia, Paralysis, Pulselessness, Pain, Poikilothermia
Correct answer: Pain, Pallor, Pulselessness, Paresthesia, Paralysis, Pressure
The 6 Ps of vascular assessment are Pain, Pallor, Pulselessness, Paresthesia, Paralysis, and Pressure (or Poikilothermia), used to detect compartment syndrome and vascular compromise.
Question 5: Which of the following splint types is used to immobilize the thumb and wrist for conditions such as de Quervain's tenosynovitis?
- Ulnar gutter splint
- Thumb spica splint (Correct answer)
- Volar wrist splint
- Sugar tong splint
Correct answer: Thumb spica splint
A thumb spica splint immobilizes the thumb and wrist, making it appropriate for scaphoid fractures, de Quervain's tenosynovitis, and thumb UCL injuries.
Question 6: When removing a cast with a cast saw, the blade oscillates rather than rotates. Why is this design important?
- It cuts faster through fiberglass
- It prevents lacerating skin by stopping when it meets soft tissue (Correct answer)
- It reduces heat generated during cutting
- It allows the technician to cut in any direction
Correct answer: It prevents lacerating skin by stopping when it meets soft tissue
The oscillating blade of a cast saw cuts rigid casting material but stops cutting when it contacts the yielding soft tissue of the skin, preventing lacerations.
Question 7: A displaced femoral neck fracture in an elderly patient is most often treated with which surgical option to reduce risk of avascular necrosis?
- Open reduction and internal fixation with cannulated screws
- Hemiarthroplasty or total hip arthroplasty (Correct answer)
- Long leg casting
- Skeletal traction alone
Correct answer: Hemiarthroplasty or total hip arthroplasty
Displaced femoral neck fractures in elderly patients are commonly treated with hemiarthroplasty or total hip arthroplasty because fixation carries a high risk of AVN and nonunion.
OTC Orthopaedic Technologist 4
Which bone is most commonly fractured in the wrist and is at high risk for avascular necrosis due to its blood supply?