What are the next steps in managing a patient with an oblique, non-displaced fracture of the proximal phalanx of the little finger after self-reduction of a lateral dislocation of the PIP (proximal interphalangeal) joint?

Assessing for Malrotation in Proximal Phalanx Fracture After PIP Joint Dislocation

The most critical assessment for malrotation involves examining finger alignment during active flexion, as rotational deformities become most apparent when the fingers flex toward the scaphoid tubercle—any scissoring, overlap, or deviation from parallel alignment indicates malrotation requiring immediate intervention. 1

Key Clinical Questions to Diagnose Malrotation

Active Range of Motion Assessment

• Ask the patient to actively flex all fingers together into a fist and observe whether the fingernails align in parallel planes—normally, all fingers should point toward the scaphoid tubercle without crossing over adjacent digits 1, 2
• Examine for scissoring during active flexion, where the injured little finger crosses over or under the ring finger, which is the hallmark sign of rotational malalignment 1
• Compare the cascade of the fingers when making a gentle fist—the injured finger should follow the same arc as the contralateral hand 2

Static Alignment Evaluation

• Inspect the fingernail orientation at rest—all fingernails should be in the same plane when fingers are extended; rotational deformity causes the nail of the affected finger to point in a different direction 1
• Assess the pulp-to-pulp relationship by having the patient touch each fingertip to the thumb—the injured finger should contact the thumb pad symmetrically compared to the opposite hand 2
• Examine finger alignment in full extension—look for any rotational deviation where the finger appears twisted along its longitudinal axis 1

Functional Testing

• Test grip strength and observe finger positioning during power grip—malrotation will cause the affected finger to assume an abnormal position relative to adjacent digits 3
• Ask about functional difficulties such as inability to grip objects properly or fingers "getting in the way" of each other, which suggests rotational malalignment 2

Critical Timing Considerations

Malrotation assessment must be performed immediately, as your patient is only 2 days post-injury and still within the window for non-operative correction if caught early. 1 The absence of scissoring at the time of injury does not exclude the development of malrotation after the fracture was identified, particularly with oblique fracture patterns that are inherently rotationally unstable. 3, 4

Red Flags Requiring Immediate Intervention

• Any degree of scissoring during active flexion mandates fracture realignment, as even 5 degrees of rotational deformity translates to 1.5 cm of fingertip deviation 4
• Persistent or worsening pain during the first 2 weeks should prompt reevaluation for malrotation or loss of reduction 5, 1
• Inability to achieve full active flexion without finger overlap suggests rotational malalignment requiring correction 2

Common Pitfalls to Avoid

The most dangerous pitfall is assuming that non-displaced fractures on radiographs cannot have rotational deformity—standard radiographs are notoriously poor at detecting rotation, which is a purely clinical diagnosis. 4 The oblique fracture pattern in your patient carries inherent rotational instability even when non-displaced on X-ray. 3, 4

Buddy taping to the ring finger, while providing support, can mask subtle malrotation during examination—you must remove the splint and assess active motion of the little finger independently before making treatment decisions. 6

Management Algorithm Based on Findings

If No Malrotation Detected:

• Continue conservative management with the intrinsic-plus brace for 3 weeks as planned 1
• Institute immediate active finger motion exercises for all uninvolved joints to prevent stiffness, which is the most functionally disabling complication 5, 1
• Obtain repeat radiographs at 10-14 days to ensure fracture position is maintained 7

If Malrotation Present:

• Immediate closed reduction under digital block should be attempted for fractures less than 1 week old 4
• Surgical intervention is indicated if closed reduction fails to correct rotation or if the fracture is unstable after reduction 3, 4
• Percutaneous fixation yields the highest post-operative range of motion (86.5 degrees) for unstable proximal phalanx fractures requiring surgical stabilization 3

Active finger motion exercises should be performed immediately following diagnosis regardless of treatment method, as finger motion does not adversely affect adequately stabilized fractures but significantly reduces the risk of debilitating stiffness. 5, 1