Multifragmentary extraarticular or diaphyseal fracture

Multifragmentary metaphyseal and shaft fractures of the middle phalanx are classified according to AO/OTA as 78.2–5.2.1A, 2B, 2C, and 3A, respectively, where 2–5 indicates which finger is injured.

$Illustration of multifragmentary extraarticular and diaphyseal fracture of the middle phalanx, AO/OTA 78.2–5.2.1A, 2B, 2C, 3A.$

Comminuted fractures are rarely isolated injuries, as they usually result from high-energy trauma (crushing). Soft-tissue lesions are associated with edema, fibrosis, and stiffness.

Although there is an abundant blood supply in the hand, the soft tissues attached to multiple small fragments are at risk of poor perfusion. Both the soft tissues and the bone fragments are at risk of poor healing.

Rotational deformity

In fractures distal to the proximal interphalangeal (PIP) joint, overlap of neighboring fingers may occur when there is substantial rotational displacement.

$Illustration of oblique extraarticular and diaphyseal fractures of the middle phalanx, overlap may occur with rotational displacement.$

Outcomes

Outcome of fractures of the middle phalanx is usually more favorable than those of the proximal phalanx. This is largely because limitations in distal interphalangeal (DIP) joint motion are not such a disability as similar stiffness of the PIP and metacarpophalangeal (MCP) joints.

AP view of the whole hand and true lateral view of the finger are needed for diagnosis.

$Illustration of multifragmentary extraarticular and diaphyseal fracture of the middle phalanx, AP and lateral views needed.$