Which device would be most effective for achieving a functional grasp in a patient with C6 AIS A SCI who has functional wrist extension but no active finger flexion?

Which device would be most effective for achieving a functional grasp in a patient with C6 AIS A SCI who has functional wrist extension but no active finger flexion?

• A. Mobile arm support
• B. Universal cuff
• C. Rocker knife
• D. Tenodesis splint

Answer: (D)

The key idea is using the tenodesis effect: when the wrist is extended, the finger flexors are put on stretch in a way that causes the fingers to flex passively around an object. In someone with a C6 AIS A SCI, wrist extension is typically preserved, while active finger flexion is lost. A tenodesis splint positions the wrist to extend, so the fingers automatically curl into a grasp without requiring active finger flexion. This creates a functional grasp and release with minimal voluntary finger movement. Mobile arm support helps stabilize the arm but doesn’t directly enable finger flexion. A universal cuff relies on finger flexion and hand shape to hold objects. A rocker knife requires some usable finger control and a stable grasp pattern. The tenodesis splint uniquely converts available wrist movement into a reliable grasp, making it the best choice for enabling functional grasp in this scenario.

The key idea is using the tenodesis effect: when the wrist is extended, the finger flexors are put on stretch in a way that causes the fingers to flex passively around an object. In someone with a C6 AIS A SCI, wrist extension is typically preserved, while active finger flexion is lost. A tenodesis splint positions the wrist to extend, so the fingers automatically curl into a grasp without requiring active finger flexion. This creates a functional grasp and release with minimal voluntary finger movement.

Mobile arm support helps stabilize the arm but doesn’t directly enable finger flexion. A universal cuff relies on finger flexion and hand shape to hold objects. A rocker knife requires some usable finger control and a stable grasp pattern. The tenodesis splint uniquely converts available wrist movement into a reliable grasp, making it the best choice for enabling functional grasp in this scenario.