Review Question - QID 217389

This patient has sustained a rotatory volar PIP dislocation, which commonly results in a proximal phalanx that has button-holed through the central slip and lateral band. Flexion of the PIPJ to 90 degrees can relax the volarly displaced lateral band and allow for successful reduction.

There are three main types of phalangeal dislocations: dorsal, volar, and lateral. Volar dislocations are further broken down into simple and rotatory. Simple dislocations result in a tear of the central slip, allowing the middle phalanx to displace directly volar. These are reduced with flexion and a dorsally directed force at the base of the middle phalanx. Rotatory dislocations involve volar translation of the middle phalanx with a rupture of one of the collateral ligaments and one of the condyles of the proximal phalanx button-holes through the lateral band and central slip. This can make reduction challenging. If only direct traction is applied, the lateral band and central slip will tighten around the condyle and prevent reduction. If closed reduction is not successful, open reduction through a dorsolateral approach is utilized to also evaluate the collateral ligament and allow for reconstruction if necessary.

Khouri et al provide a review article discussing the diagnosis and treatment of proximal interphalangeal joint injuries. They review fractures of the head of the proximal phalanx, dislocations, fracture-dislocations, and fractures of the base of the middle phalanx. They state the main goal of any treatment is to provide a congruent PIPJ and allow for early motion, as the PIPJ is notorious for the development of arthrofibrosis after injury.

Saitta and Wolf review PIPJ dislocations specifically. In the review, a majority of PIPJ dislocations can be managed by closed means, but a select few need surgical intervention. They discuss primary soft tissue repair, tenodesis, and suture anchor reconstruction techniques. Late sequelae of PIPJ dislocations involve contracture, so initial surgical intervention should allow for a stable joint and early range of motion to minimize this complication.

Figure A is the AP and lateral radiographs of a rotatory volar PIPJ dislocation. The AP shows the rotatory nature of this injury the best as you get a direct AP view of the proximal phalanx and an oblique view of the dislocated middle phalanx. Illustration A shows an intraoperative picture of an irreducible rotatory PIPJ dislocation. The black arrow is the radial-sided proximal phalanx condyle trapped between the central slip (black arrowhead) and volar subluxed lateral band (white arrow).

Incorrect answers:
Answer 1: Although volar rotatory dislocations require open reduction more often than dorsal and lateral dislocations, they do not ALWAYS require surgery.
Answer 2: Direct in-line traction will likely cause the noose of the lateral band and central slip to tighten around the proximal phalanx condyle and prevent reduction.
Answer 4: Hyperextension of a rotatory volar dislocation will cause further volar translation of the lateral band, and likely not result in a successful reduction.
Answer 5: PIPJ dislocations are unlikely to spontaneously reduce without some sort of external force applied.