Treatment of Radial-Sided PIP Joint Avulsion Fracture
For a possible avulsion fracture on the radial aspect of the PIP joint, initial conservative treatment with extension splinting is recommended for stable injuries, with close monitoring for displacement or rotation that would necessitate surgical intervention.
Initial Assessment and Classification
The radial aspect of the PIP joint can sustain avulsion fractures involving either the collateral ligament attachment or, less commonly, combined injuries. The critical first step is determining joint stability and fracture displacement 1, 2.
Key radiographic parameters to evaluate:
- Degree of fragment displacement and rotation (not just fragment size) 1
- Presence of joint subluxation or dislocation 1
- Articular congruity and step-off 2
A common pitfall is focusing solely on fragment size rather than displacement and rotation, which are the actual predictors of conservative treatment failure 1.
Conservative Management Approach
Initial treatment for stable PIP joints without significant displacement should be extension splinting for 2 weeks, followed by active range of motion exercises 3, 1.
- Extension splinting prevents flexion contracture while allowing the volar plate or collateral ligament to heal 3
- Fragment size and comminution are NOT predictive of treatment success 1
- What matters is displacement, rotation, and whether joint dislocation occurred at injury 1
Contraindications to conservative treatment:
- Joint dislocation at time of injury 1
- Significant fragment displacement or rotation on radiographs 1
- Persistent joint subluxation after closed reduction 2
Surgical Indications and Timing
If conservative treatment fails (persistent pain, limited motion, or instability), delayed fragment excision at an average of 75 days produces favorable outcomes 1. This approach is preferable to immediate surgery for borderline cases because:
- Postoperative joint protection is not necessary after delayed excision 1
- Pain resolves and range of motion improves after fragment removal 1
- It avoids unnecessary surgery in cases that would have healed conservatively 1
For unstable fracture-dislocations requiring immediate surgery:
- Interfragmentary screw fixation is preferable to plate fixation when technically feasible 4
- Screw fixation results in better DIP joint range of motion (average 53° vs 34° flexion) 4
- Plate fixation has higher rates of hardware removal and need for arthrolysis 4
- If plating is necessary, use the shortest plate possible to minimize stiffness 4
Post-Treatment Protocol
After conservative treatment or surgical fixation:
- Splinting for 2 weeks maximum 3, 4
- Early active range of motion exercises starting at 2 weeks 4
- Monitor for flexion contracture development, which may require arthrolysis if >30° 4
The evidence strongly supports that almost all volar plate avulsion fractures of stable PIP joints should receive initial conservative treatment, with surgery reserved for clear failures 1. This staged approach optimizes outcomes while avoiding unnecessary operative intervention.