What type of splint is recommended for a proximal phalanx fracture?

Splinting for Proximal Phalanx Fractures

For proximal phalanx fractures, a custom-molded two-component thermoplastic splint that immobilizes the metacarpophalangeal joint while allowing motion of the proximal and distal interphalangeal joints is the recommended approach. 1

Splinting Principles for Proximal Phalanx Fractures

• The splint should immobilize the metacarpophalangeal joint in 70-90 degrees of flexion (intrinsic plus position) while allowing for motion of the proximal and distal interphalangeal joints 2
• This position creates tension in the extensor aponeurosis which covers two-thirds of the proximal phalanx, providing firm stabilization of the fracture 2
• The wrist should be positioned in approximately 30 degrees of dorsiflexion to optimize fracture alignment 2
• For stable fractures with minimal angulation (less than 10 degrees), buddy taping to an adjacent uninjured finger can provide adequate support 3

Splint Design and Application

• A custom-molded thermoplastic splint is preferable as it can be tailored to the individual's hand size and fracture pattern 1
• The splint should extend beyond the fracture site to include the metacarpophalangeal joint for stability 1
• Padding should be placed between fingers if buddy taping is used to prevent skin maceration 4
• The splint should allow for radiographic evaluation without removal when possible 1

Duration of Immobilization

• Immobilization should be maintained until clinical and radiographic evidence of healing, typically 4-6 weeks 3
• Radiographic follow-up is recommended at approximately 3 weeks to assess healing progress 4
• Early active motion of the interphalangeal joints should be encouraged to prevent stiffness while the metacarpophalangeal joint remains immobilized 1, 2

Special Considerations

• For comminuted proximal phalanx fractures, a more rigid immobilization may be necessary, potentially requiring plate fixation rather than splinting alone 5
• For fractures with significant displacement (>3mm), angulation (>10°), or intra-articular involvement, surgical management may be indicated instead of conservative treatment 3, 5
• If there is concern for rotational deformity, clinical assessment should include evaluation of finger alignment when partially flexed 3

Benefits of Dynamic Treatment

• The dynamic treatment approach with this type of splint allows for simultaneous bone healing and recovery of motion 1
• Studies have shown that 86% of patients treated with dynamic splinting achieve full range of motion at follow-up 2
• This approach prevents the stiffness commonly associated with static immobilization methods 2
• The splint can be used for both nonsurgical management and post-surgical stabilization 1