What is the treatment for a dorsal dislocation of the proximal interphalangeal (PIP) joint of the index finger?

Treatment for Dorsal Dislocation of PIP Joint of Index Finger

Immediate closed reduction followed by buddy taping and early active motion is the treatment of choice for simple dorsal PIP dislocations, with radiographs obtained before and after reduction to rule out fracture-dislocations requiring surgical intervention.

Initial Assessment and Reduction

Radiographic Evaluation

• Obtain 3-view radiographs immediately before attempting reduction to differentiate simple dislocations from fracture-dislocations, as bony fragments involving ≥40% of the articular surface require surgical management 1, 2
• Post-reduction radiographs are mandatory to confirm concentric joint reduction and exclude fracture fragments 3

Closed Reduction Technique

• Most dorsal PIP dislocations reduce easily with longitudinal traction and gentle pressure over the dorsally displaced middle phalanx 4, 5
• The palmar plate typically returns to its anatomic position upon closed reduction in simple dislocations, with the collateral ligaments realigning without interposition 2
• If closed reduction fails after one or two attempts, suspect soft tissue interposition (typically the palmar plate buttonholing between joint surfaces) and proceed directly to open reduction 4, 5

Post-Reduction Management

Immobilization Strategy

• Apply a dorsal extension-block splint maintaining the PIP joint in 20-30 degrees of flexion to prevent hyperextension while allowing flexion 2
• Buddy tape the index finger to the middle finger for additional stability 3
• Duration of splinting: 3-4 weeks for stable reductions 2

Early Active Motion Protocol

• Begin active PIP flexion exercises immediately within the protective splint to prevent the most functionally disabling complication—joint stiffness 3, 6
• Active motion of uninvolved MCP and DIP joints should start immediately 3, 6
• Passive extension exercises are contraindicated during the first 3-4 weeks 2

Critical Assessment for Malrotation

• Examine finger alignment during active flexion at every follow-up visit, as rotational deformities become apparent when fingers flex toward the scaphoid tubercle 3
• Look for scissoring (finger crossing over adjacent digits), which is the hallmark sign of rotational malalignment requiring immediate intervention 3
• Compare the cascade of fingers when making a gentle fist to the contralateral hand 3

Surgical Indications

Absolute Indications for Open Reduction

• Irreducible closed dislocations after one or two gentle attempts, suggesting volar plate or collateral ligament interposition 4, 5
• Open (compound) dislocations require open reduction combined with debridement 7, 4
• Fracture-dislocations with volar fragment ≥40% of articular surface 1, 2
• Palmar subluxation of the middle phalanx on lateral radiographs (>3mm displacement) 6

Relative Surgical Indications

• Chronic dislocations (>2-3 weeks old) may require distraction techniques or open reduction 1
• Incarceration of flexor tendons in the fracture site (rare) 7

Follow-Up Protocol

Timing of Reassessment

• First follow-up at 7-10 days to assess for malrotation and obtain repeat radiographs 3
• Weekly visits during the first 3-4 weeks to monitor reduction stability 3
• Any unremitting pain during immobilization warrants immediate reevaluation for loss of reduction or malrotation 3, 6

Expected Outcomes

• Simple dislocations treated with closed reduction and early motion typically achieve 12-91 degrees of PIP motion 1
• Stiffness is the most common complication and is directly related to prolonged immobilization without active motion 3, 6

Common Pitfalls to Avoid

• Never attempt multiple forceful closed reduction attempts, as this increases soft tissue trauma and the risk of converting a simple dislocation to a complex injury requiring surgery 4, 5
• Avoid rigid immobilization in full extension, which promotes flexion contractures and stiffness 2
• Do not delay radiographs, as fracture-dislocations require different management algorithms 6, 8
• Failure to assess for malrotation within the first 1-2 weeks may result in permanent rotational deformity requiring corrective osteotomy 3