CPT Anatomy & Physiology Fundamentals 3 — Questions and Answers
Question 1: Which type of joint allows the greatest range of motion and is most commonly affected by conditions requiring lower-limb prosthetics?
- Fibrous joint
- Cartilaginous joint
- Synovial joint (Correct answer)
- Gomphosis
Correct answer: Synovial joint
Synovial joints provide the greatest range of motion and include joints like the hip and knee that are central to prosthetic gait.
Question 2: The ischial tuberosity is a critical loading point in ischial containment sockets. To which bone does this structure belong?
- Ilium
- Pubis
- Ischium (Correct answer)
- Femur
Correct answer: Ischium
The ischial tuberosity is the roughened inferior projection of the ischium and bears body weight during sitting.
Question 3: Which physiological process causes post-amputation edema in the residual limb, and understanding it helps technicians recommend appropriate sock ply management?
- Decreased oncotic pressure
- Disrupted lymphatic drainage (Correct answer)
- Increased venous return
- Reduced arterial perfusion
Correct answer: Disrupted lymphatic drainage
Amputation disrupts lymphatic vessels, impairing fluid drainage and causing edema that the prosthetic socket must accommodate.
Question 4: A residual limb shows a scar over a bony prominence. Which anatomical principle explains why this area is at highest risk for skin breakdown?
- Increased blood perfusion at scar tissue
- Reduced tissue compressibility over bony prominences (Correct answer)
- Scar tissue has heightened pain sensitivity
- Bony prominences attract more friction
Correct answer: Reduced tissue compressibility over bony prominences
Tissue over bony prominences has less compressibility, concentrating interface pressure and increasing skin breakdown risk.
Question 5: Which of the following muscles, when spastic or contracted in a transtibial amputee, most commonly causes a knee flexion contracture?
- Rectus femoris
- Vastus medialis
- Hamstrings (Correct answer)
- Tibialis anterior
Correct answer: Hamstrings
Hamstring spasticity or contracture causes persistent knee flexion, complicating transtibial prosthetic alignment.
Question 6: Periosteum covers the external surface of bone. Which cell layer within the periosteum is directly responsible for bone repair after fracture?
- Fibrous outer layer
- Inner cambium (osteogenic) layer (Correct answer)
- Haversian system
- Sharpey's fibers
Correct answer: Inner cambium (osteogenic) layer
The inner cambium (osteogenic) layer of the periosteum contains osteoprogenitor cells that proliferate during bone healing.
Question 7: Which nerve is responsible for sensation over the dorsum of the foot and is commonly assessed in dysvascular lower-limb amputees?
- Sural nerve
- Saphenous nerve
- Deep peroneal nerve (Correct answer)
- Tibial nerve
Correct answer: Deep peroneal nerve
The deep peroneal nerve innervates the first web space and dorsal foot, and its assessment helps evaluate residual limb neurological status.
CPT Anatomy & Physiology Fundamentals 3
Which type of joint allows the greatest range of motion and is most commonly affected by conditions requiring lower-limb prosthetics?