Treatment of Non-Displaced Fracture at the Base of the Proximal Phalanx of the Fifth Digit
A non-displaced fracture at the base of the proximal phalanx of the fifth digit should be treated conservatively with buddy taping to the fourth digit and immediate mobilization, avoiding rigid immobilization that can lead to joint stiffness.
Conservative Management Approach
The optimal treatment prioritizes functional recovery over anatomical perfection, particularly for the fifth digit where minor malalignment is well-tolerated 1.
Immobilization Technique
Buddy taping is the preferred method:
- Tape the injured fifth digit to the adjacent fourth digit using soft padding between fingers 1
- This provides dynamic stabilization while allowing controlled motion 1
- Avoid rigid splinting or casting, which commonly results in decreased finger mobility despite achieving exact fracture reduction 2, 3
Mobilization Protocol
Immediate mobilization should begin:
- Active range of motion exercises in both the proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints prevent stiffness and rotational deformities 3
- The metacarpophalangeal (MCP) joint can be gently mobilized as tolerated 3
- Early functional movement achieves bony healing and full mobility simultaneously rather than sequentially 3
Alternative Functional Splinting (If Needed)
If additional support is required for patient comfort or fracture stability:
Use an intrinsic-plus position splint:
- Position the wrist in 30 degrees of dorsiflexion 3
- Flex the MCP joint to 70-90 degrees 3
- Keep the interphalangeal joints free for active motion 3
- This position tightens the extensor aponeurosis, which covers two-thirds of the proximal phalanx and provides natural splinting 3
Expected Outcomes
The evidence strongly supports conservative management:
- 100% fracture union rate with buddy taping and immediate mobilization 1
- 86% of patients achieve full range of motion 3
- High patient satisfaction with minimal residual pain 1
- Malrotation requiring surgery is rare (occurring in <6% of cases) 1
- No cases of nonunion or delayed union 1
Monitoring Requirements
Follow-up radiographs should be obtained:
- At 1-2 weeks to confirm maintenance of alignment 4
- At 4 weeks to assess healing progression 4
- Buddy taping typically continues for 3-4 weeks until clinical union 1
Red Flags Requiring Surgical Referral
Refer to orthopedic surgery if:
- Angulation exceeds 10 degrees in any plane 4
- Malrotation is present (assessed by observing the digital cascade with fingers flexed) 4, 5
- Displacement occurs or increases on follow-up radiographs 2
- The fracture becomes unstable after attempted closed reduction 5
Common Pitfalls to Avoid
- Do not use rigid plaster immobilization for stable non-displaced fractures, as this leads to interphalangeal joint stiffness that is difficult to reverse 3
- Do not delay mobilization beyond what is necessary for initial pain control, as early motion is critical for optimal functional outcomes 3, 1
- Do not ignore rotational alignment on clinical examination—even subtle malrotation can cause significant functional impairment 4, 5