Assessment of Forearm Rotational Control Using 4 Upper Extremity Immobilization Constructs

Area of Science:

• Orthopedic surgery
• Biomechanics
• Fracture management

Background:

• Forearm immobilization is crucial for treating distal radius, scaphoid, and metacarpal fractures.
• Various splinting and casting techniques exist, each with potential differences in rotational control.

Purpose of the Study:

• To compare the rotational immobilization effectiveness of sugar-tong splints (STS), short arm casts (SAC), Munster casts (MC), and long arm casts (LAC).
• To evaluate immobilization at the distal radioulnar joint (DRUJ), carpus, and metacarpals.

Main Methods:

• Cadaveric upper extremity specimens were used with K-wires to measure rotational arcs.
• Immobilization was sequentially applied with STS, SAC, MC, and LAC.
• Supination and pronation forces were applied to quantify rotational motion.

Main Results:

• Long arm casts (LAC) and Munster casts (MC) provided the most effective rotational immobilization.
• Above-elbow constructs (MC, LAC) were significantly superior to below-elbow constructs (SAC).
• Circumferential constructs (SAC, MC, LAC) outperformed the non-circumferential sugar-tong splint (STS).

Conclusions:

• Both circumferential casting and proximal extension improve wrist rotational control.
• Extending immobilization beyond the elbow did not provide additional rotational stability.