CHT Splinting & Orthotic Fabrication Flashcards

Relative motion flexion orthoses (yoke splints) are used to treat:

Answer: Sagittal band rupture (extensor tendon subluxation)

Relative motion flexion orthoses hold the involved MCP in slight relative flexion compared to adjacent digits, reducing extensor tendon subluxation while maintaining function in sagittal band injuries.

When splinting for de Quervain tenosynovitis, which structure must be immobilized?

Answer: Thumb CMC and MCP joints (thumb spica)

A thumb spica orthosis immobilizes the thumb CMC and MCP joints to rest the APL and EPB tendons within the first dorsal compartment, the structures irritated in de Quervain tenosynovitis.

Low-temperature thermoplastic materials with high resistance (drapability) are best suited for:

Answer: Large orthoses requiring structure over long levers

High-resistance (less drapable) thermoplastics maintain their shape under gravity, making them appropriate for large orthoses like elbow or forearm-based designs that need structural rigidity.

A mallet finger orthosis should immobilize the DIP joint in:

Answer: Full extension or slight hyperextension (0–5°)

The DIP joint is splinted in full extension or slight hyperextension (0–5°) to allow the disrupted terminal extensor tendon to heal in an approximated position.

The purpose of including a metacarpal bar in a hand-based orthosis is to:

Answer: Distribute pressure across the palm and stabilize the MCP joints

A metacarpal bar distributes orthotic forces across the transverse metacarpal arch and serves as the anchor for MCP joint positioning or digit outriggers.

Buddy taping or a buddy strap orthosis is most appropriate for:

Answer: Stable PIP fractures or collateral ligament sprains

Buddy strapping pairs the injured digit to an adjacent stable digit, providing lateral support for collateral ligament sprains or stable PIP fractures while allowing protected early motion.