Thumb Proximal Phalanx Fracture Management
Immobilization Technique
- Immobilize a proximal thumb phalanx fracture with a thumb‑spica splint that holds the thumb in an intrinsic‑plus (balanced) position while permitting full wrist flexion‑extension; maintain rigid immobilization for 3–6 weeks. 1
- The splint must lock the metacarpophalangeal (MCP) joint but allow interphalangeal (IP) joint motion to reduce the risk of joint stiffness. 1
Imaging
- Obtain immediate three‑view radiographs (postero‑anterior, lateral, and oblique) to evaluate fracture displacement, articular involvement, and malrotation. 1
- Do not rely on only two‑view radiographs, as they may miss displacement, articular involvement, or malrotation. Use three‑view imaging for comprehensive assessment. [1][5]
Rehabilitation
- Initiate active IP‑joint range‑of‑motion exercises immediately while the MCP joint remains splinted, to prevent stiffness of the distal thumb joints. 4
- Instruct the patient to move the IP joint through a complete range of motion regularly throughout the immobilization period. 1
Indications for Surgical Referral
- Refer for orthopedic consultation if any of the following are present:
- Fracture displacement greater than 3 mm.
- Involvement of more than one‑third of the articular surface.
- Interfragmentary gap exceeding 3 mm.
- Clinical malrotation (e.g., scissoring of the thumb when the patient makes a fist).
All criteria are based on radiographic and clinical assessment. 1
Follow‑Up Protocol
- Obtain repeat radiographs at 10–14 days to confirm that fracture alignment is maintained. 1
- Continue radiographic monitoring at 3 weeks and again at the end of immobilization. 1
- Total immobilization time for stable, minimally displaced fractures should be 3–6 weeks. 1