Mallet Finger Treatment
For acute mallet finger injuries, conservative treatment with continuous splinting of the distal interphalangeal joint (DIPJ) in extension for 6-12 weeks is the primary treatment, with surgery reserved for specific indications including open injuries, fractures involving ≥1/3 of the articular surface with subluxation, or failed conservative management. 1, 2
Initial Assessment
- Obtain radiographs with at least 3 views to evaluate fracture pattern, degree of displacement, articular involvement, and associated soft tissue injuries 3
- Clinical diagnosis is straightforward, but imaging is mandatory to classify the injury and guide treatment 1
- Classify using Tubiana's system: tendinous rupture vs. bony avulsion, with attention to fragment size and DIPJ subluxation 1
Conservative Treatment (First-Line for Most Cases)
Indications
- All tendinous mallet finger injuries 1, 2
- Bony avulsions involving <1/3 of articular surface without subluxation 2
- Reducible subluxations (stage III) 1
Splinting Protocol
- Immobilize DIPJ in slight hyperextension for tendinous injuries or neutral/straight position for bony avulsions 1
- Duration: 6-12 weeks of continuous full-time splinting 1, 4
- Stack splints demonstrate superior grip strength outcomes compared to K-wire immobilization and aluminum orthoses 5
- Various splint types (stack, thermoplastic, aluminum) show comparable results for extensor lag and total active motion 5
- Consider additional 4 weeks of night splinting after full-time immobilization 4
Critical Compliance Points
- Patient must maintain continuous splinting—even brief interruptions can compromise healing 1, 2
- Success depends entirely on patient adherence to the splinting protocol 1
Surgical Treatment
Indications
- Open injuries 2
- Avulsion fractures involving ≥1/3 of articular surface 2
- Palmar subluxation of distal phalanx that is not reducible with splinting (stage IV) 1, 2
- Failed conservative treatment 2
- Fracture fragment displacement >3mm 3
Surgical Approach
- Extra-articular pinning is recommended for irreducible subluxations (stage IV) 1
- Various techniques exist including different approaches, reduction methods, and fixation options 1
- Newer techniques avoiding cartilage damage show promise for bony mallet fingers 6
Post-Treatment Management and Monitoring
Early Mobilization Strategy
- Begin active finger motion exercises immediately after diagnosis for adequately stabilized fractures 3
- Finger motion does not adversely affect properly stabilized fractures 3
- Hand stiffness is the most functionally disabling complication—prevention through early motion is critical 3
Follow-Up Assessment
- Monitor for proper fracture healing and restoration of finger function 3
- Measure extension lag: expect reduction from ~28° initially to ~3° at final follow-up 4
- Assess flexion angle: expect ~68° at final follow-up 4
- Unremitting pain during follow-up warrants immediate reevaluation for complications 3
Expected Outcomes
- With proper conservative treatment, 56% achieve excellent results and 25% achieve good results by Crawford criteria 4
- Mean extension lag improves significantly from 28.3° to 2.6° with appropriate splinting 4
- Success depends critically on patient compliance with the prolonged immobilization protocol 1, 4
Critical Pitfalls to Avoid
- Failure to encourage early motion of non-immobilized joints leads to severe stiffness that is difficult to reverse 3
- Inadequate splinting duration or interruptions in splinting compromise tendon healing 1, 4
- Overlooking displacement or articular involvement on radiographs leads to poor functional outcomes 3
- Untreated mallet finger progresses to chronic deformity, swan-neck deformity, and DIPJ osteoarthritis 1