OTC Orthopaedic Technologist Certified Orthopaedic Appliances and Bracing 4 — Questions and Answers
Question 1: A patient with rheumatoid arthritis develops ulnar drift of the metacarpophalangeal joints. Which orthosis design best addresses this deformity?
- Cock-up wrist splint
- Ring splint
- Ulnar deviation orthosis with radially directed corrective straps (Correct answer)
- Resting hand orthosis in intrinsic-plus position
Correct answer: Ulnar deviation orthosis with radially directed corrective straps
An ulnar deviation orthosis with radially directed corrective straps applies forces that counteract the characteristic ulnar drift at the MCP joints seen in rheumatoid arthritis.
Question 2: The CROW (Charcot Restraint Orthotic Walker) boot is primarily indicated for which patient population?
- Post-tibial tendon rupture
- Acute ankle sprains in athletes
- Charcot neuroarthropathy in diabetic patients (Correct answer)
- Heel spur syndrome unresponsive to orthotics
Correct answer: Charcot neuroarthropathy in diabetic patients
The CROW boot immobilizes and offloads the foot in patients with Charcot neuroarthropathy to prevent progressive bony collapse and ulceration.
Question 3: When applying a short arm cast, how far distally should the cast extend on the palmar surface to preserve metacarpophalangeal joint motion?
- Proximal palmar crease
- Distal palmar crease (Correct answer)
- Midpalm level
- Web space of thumb
Correct answer: Distal palmar crease
Ending the cast at the distal palmar crease allows full MCP flexion while still adequately immobilizing the wrist and distal radius.
Question 4: Which principle explains why a three-point pressure system is effective in orthotic management of spinal deformities?
- It distributes load equally across all vertebral levels
- Two counter-forces oppose one primary corrective force to create moment correction (Correct answer)
- It uses electrical stimulation to activate paraspinal muscles
- It stretches ligamentous structures through distraction
Correct answer: Two counter-forces oppose one primary corrective force to create moment correction
The three-point system applies one primary corrective force at the apex of the deformity while two counter-forces above and below create a corrective bending moment.
Question 5: A mallet finger injury resulting from disruption of the terminal extensor tendon is typically treated with which orthosis position?
- DIP joint in slight flexion
- DIP joint in full extension or slight hyperextension (Correct answer)
- PIP joint in extension with DIP free
- Full finger extension in a static hand orthosis
Correct answer: DIP joint in full extension or slight hyperextension
A mallet finger splint holds the DIP joint in full extension or slight hyperextension continuously for 6-8 weeks to allow the extensor tendon to heal in continuity.
Question 6: Which type of foot orthosis is best suited to address plantar fasciitis by unloading the plantar fascia insertion?
- Rigid arch support with metatarsal pad
- Heel cup with plantar fascia groove and medial arch support (Correct answer)
- Full-length flat insole
- Toe separator with metatarsal dome
Correct answer: Heel cup with plantar fascia groove and medial arch support
A heel cup with a plantar fascia groove and medial arch support reduces tension at the calcaneal insertion while controlling pronation that stresses the fascia.
Question 7: After application of a fiberglass cast, what is the minimum time a technologist should typically advise a patient to wait before bearing full weight on a lower extremity cast?
- Immediately upon completion
- 20-30 minutes (Correct answer)
- 2-4 hours
- 24 hours
Correct answer: 20-30 minutes
Fiberglass casting tape reaches maximum structural strength within 20-30 minutes of application, after which it can safely support weight bearing.
OTC Orthopaedic Technologist Certified Orthopaedic Appliances and Bracing 4
A patient with rheumatoid arthritis develops ulnar drift of the metacarpophalangeal joints.
Which orthosis design best addresses this deformity?