Volar Plate Injury to the Proximal Interphalangeal Joint (PIPJ)
Summary
The Volar Plate is a thick fibrocartilaginous ligament on the palmar aspect of the Proximal Interphalangeal Joint (PIPJ), preventing hyperextension. Injury occurs via a forced hyperextension mechanism (e.g., ball sport "jammed finger"). It ranges from a simple ligament sprain to a complete rupture or bony avulsion fracture. The primary goal of management is to maintain joint stability while preventing stiffness. Prolonged immobilisation leads to permanent flexion contractures. Most injuries are stable and managed with short-term protection (buddy strapping) and early mobilisation. Unstable injuries (large articular fractures with dorsal subluxation) require extension block splinting or surgery. [1,2]
Key Facts
- Mechanism: Hyperextension of PIPJ.
- Anatomy: The Volar Plate originates on the proximal phalanx and inserts into the base of the middle phalanx. It forms the floor of the joint.
- Radiology: Often shows a small bony avulsion fleck at the base of the middle phalanx (Volar aspect).
- Golden Rule: "Movement is Life". The PIPJ is unforgiving and becomes stiff very quickly. Start moving immediately (within limits of pain).
- Prognosis: Permanent fusiform swelling ("Fat Finger") is common and may persist forever, long after pain resolves.
Clinical Pearls
The "V Sign": On a true lateral X-ray, if the joint space is congruent (parallel lines), it is stable. If the joint opens up like a "V" on the dorsal side, the middle phalanx is subluxing dorsally. This is unstable and needs an extension block splint.
Rule out Central Slip: A "jammed finger" can also rupture the Central Slip (extensor tendon). Perform Elson's Test. If missed, this leads to a Boutonnière deformity.
Don't pull it!: Laypeople often pull a "dislocated" finger to reduce it. This is usually fine, but ensure post-reduction X-rays are done to check for intra-articular fractures.
Incidence
- extremely common sports injury (Basketball, Netball, Cricket, Rugby).
- Most common ligamentous injury of the hand.
Demographics
- Young active adults.
- Hand dominance: No preference.
Anatomy
- Volar Plate: Prevents hyperextension.
- Check Rein Ligaments: Lateral extensions attaching to proximal phalanx.
- Collateral Ligaments: Provide varus/valgus stability.
Injury Patterns
- Type I (Hyperextension): Avulsion of volar plate from distal insertion. Often with small bone fragment.
- Type II (Dorsal Dislocation): Complete rupture allowing middle phalanx to sit dorsal to proximal phalanx.
- Type III (Fracture-Dislocation): Large bony avulsion (>40% articular surface) compromising stability.
Symptoms
Red Flags
Look
- Swelling.
- Bruising (volar aspect).
- Cascade (fingers should point to scaphoid).
Feel
- Tenderness: Specific localised tenderness over the volar aspect of the PIPJ.
- Collaterals: Check tenderness on sides (Collateral Ligament injury often co-exists).
Move
- Active Range of Motion (ROM): Assess flexion/extension. Pain usually limits extension.
- Stability Testing:
- Hyperextension Stress: Gently extend PIPJ. Compare laxity to normal side.
- Varus/Valgus Stress: Test collaterals (at 30 degrees flexion).
Special Tests
- Elson's Test: Bend PIPJ 90° over table edge. Ask patient to extend against resistance.
- Normal: Strong extension, DIPJ remains floppy.
- Central Slip Injury: Weak extension, DIPJ becomes rigid (due to lateral band over-pull).
Imaging
- X-Ray Hand (AP, Lateral, Oblique): Mandatory.
- Look for: Avulsion fracture at base of middle phalanx.
- Lateral View: Crucial to checking congruency. Is the middle phalanx centered? Or is it slipping dorsally?
- Pilon Fracture: Comminuted intra-articular fracture (axial load).
Management Algorithm
PIPJ INJURY
↓
X-RAY
↓
┌───────────┼──────────────┐
NO FRACTURE SMALL(less than 30%) LARGE(>30%)
Or Stable AVULSION Or Subluxed
↓ ↓ ↓
STABLE STABLE UNSTABLE
↓ ↓ ↓
BUDDY STRAP BUDDY STRAP DORSAL BLOCK
Immediate Immediate SPLINT
Motion Motion Refer Hand Surg
1. Stable Injuries (Sprain or Small Avulsion)
Definition: No subluxation on X-ray, less than 30% articular surface involved.
- Buddy Strapping: Tape injured finger to adjacent finger (e.g., Middle to Ring). Acts as a dynamic splint.
- Mobilisation: IMMEDIATE. Encourage full flexion.
- Extension: Avoid forced hyperextension (passive) for 3-4 weeks.
- Edema Control: Ice, elevation, Coban tape.
2. Unstable Injuries (Dislocation or Large Fracture)
Definition: Dorsal subluxation, V-sign, or large fragment.
- Dorsal Blocking Splint:
- Splint placed on the back of the finger.
- Blocks extension at ~20-30 degrees (preventing subluxation).
- Allows checking full flexion (patient exercises within splint).
- Gradually straighten splint by 10 degrees each week over 3-4 weeks.
- Referral: Hand Surgery/Therapy.
3. Surgical Management
Rarely needed.
- Indications: Irreducible dislocation (soft tissue interposition), large fracture fragment (>40-50%) causing chronic instability.
- Procedures:
- Open Reduction Internal Fixation (ORIF).
- Volar Plate Arthroplasty.
- K-wire fixation.
Flexion Contracture (Stiffness)
- The most common complication.
- PIPJ gets stuck in flexion (cannot straighten fully).
- Cause: Prolonged immobilization or scarring of volar plate.
- Treatment: Dynamic splinting (Capener splint), Hand therapy. Hard to treat once established.
Swan Neck Deformity
- The opposite problem (Hyper-mobility).
- PIPJ Hyperextension + DIPJ Flexion.
- Cause: Laxity of volar plate from severe injury that was not protected from hyperextension.
- Treatment: Surgery (Tenodesis).
Chronic Swelling
- "Fat Finger". Fusiform thickening of collateral ligaments/scar tissue.
- Often permanent (explain this to patient early to manage expectations).
- Mild/Moderate: Good functional recovery. Full range of motion usually returns, but 5-10 degree extension lag is common (and functionally acceptable).
- Severe: Variable. High risk of stiffness/arthritis (OA) in long term.
Key Guidelines
| Guideline | Organisation | Key Recommendations |
|---|---|---|
| Hand Fractures | BSSH (British Soc. Surgery Hand) | Early mobilisation for stable volar plate injuries is superior to splinting. |
| Finger Injuries | ACEP / Emergency Medicine | X-ray everyone to rule out avulsion. Check Elson's test. |
Landmark Studies
1. Ginn et al. (2005)
- Comparison: Buddy taping vs Splinting for Volar Plate avulsions.
- Result: Buddy taping group had better range of motion and returned to work/sport sooner. No difference in pain.
- Impact: Shifted practice away from rigid aluminium splints ("Zimmer splints").
2. Effect of Immobilisation
- Studies consistently show PIPJ immobilisation >3 weeks leads to permanent stiffness.
What is the Volar Plate?
It is a strong ligament on the palm-side of your middle knuckle. It stops your finger bending backwards too far. When you jam your finger (like catching a basketball), this ligament can tear or pull off a tiny chip of bone.
Do I need a cast?
NO. The worst thing for this injury is to keep it still. If you keep it straight in a splint, it will stiffen up and may never bend properly again.
Treatment
- Buddy Strap: Tape it to the neighbour finger. This protects it but lets you move it.
- Move it: Bend it as much as pain allows. Keep it moving to pump the swelling away.
- Don't force it back: Don't push it backwards (extension) for 3-4 weeks.
Will the swelling go down?
The swelling will go down, but the knuckle often remains slightly thicker ("fat") forever. This is just scar tissue and is nothing to worry about.
Primary Sources
- Chadzynski GL, et al. Management of acute proximal interphalangeal joint hyperextension injuries. J Hand Surg Am. 2008;33:1631-1638.
- Ginn TA, et al. Prospective study of buddy taping versus splinting for volumetric and range of motion assessment. J Hand Surg Am. 2005;30:1102.
- Kiefhaber TR, Stern PJ. Fracture dislocations of the proximal interphalangeal joint. J Hand Surg Am. 1998;23:368-380.
Common Exam Questions
- Emergency Medicine: "Patient with jammed finger. X-ray shows small volar avulsion. Treatment?"
- Answer: Buddy strap and immediate mobilisation.
- Orthopaedics: "What is Elson's Test used for?"
- Answer: To detect Central Slip injury (which requires splinting in extension), distinguishing it from Volar Plate injury (which requires early movement).
- Anatomy: "Structure preventing PIPJ hyperextension?"
- Answer: Volar Plate.
- Complication: "Untreated volar plate injury leads to what deformity?"
- Answer: Swan Neck Deformity (PIPJ hyperextension, DIPJ flexion).
Viva Points
- Elson's Test Mechanism: Bending PIPJ 90° pulls central slip taut. If intact, extending against resistance is strong and lateral bands are loose (DIPJ floppy). If ruptured, lateral bands tighten to extend PIPJ, making DIPJ rigid.
- V-Sign: Importance of true lateral X-ray to detect dorsal subluxation.
Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. Clinical decisions should account for individual patient circumstances. Always consult appropriate specialists.