Mallet finger is characterized by which of the following findings?

Mallet finger is characterized by which of the following findings?

• A. The inability to actively extend the DIP joint is a hallmark.
• B. The inability to passively extend the DIP joint completely never requires surgery.
• C. Up to one-third distal extensor tendon injuries are not associated with an avulsion fracture.
• D. Immobilization of the DIP joint in flexion for 6-8 weeks.

Answer: (A)

Mallet finger is a disruption of the distal extensor mechanism at the DIP joint, most often from an avulsion of the extensor tendon off the distal phalanx. The key clinical feature is the inability to actively straighten the fingertip at the DIP—the finger droops and cannot be extended by the patient. Passive extension is possible because the joint itself can be moved into extension with help, distinguishing this injury from a complete torn extensor mechanism. Because the main concept centers on lost active extension, this finding is the most specific and reliable sign. In contrast, some mallet injuries occur with an avulsion fracture, and not all cases require surgery—large avulsion fragments or joint subluxation can necessitate operative management, so the statement that surgery is never required is not correct. Some injuries can occur without a fracture, but the hallmark remains the loss of active DIP extension. Additionally, the DIP is typically immobilized in extension during treatment, not flexion.

Mallet finger is a disruption of the distal extensor mechanism at the DIP joint, most often from an avulsion of the extensor tendon off the distal phalanx. The key clinical feature is the inability to actively straighten the fingertip at the DIP—the finger droops and cannot be extended by the patient. Passive extension is possible because the joint itself can be moved into extension with help, distinguishing this injury from a complete torn extensor mechanism.

Because the main concept centers on lost active extension, this finding is the most specific and reliable sign. In contrast, some mallet injuries occur with an avulsion fracture, and not all cases require surgery—large avulsion fragments or joint subluxation can necessitate operative management, so the statement that surgery is never required is not correct. Some injuries can occur without a fracture, but the hallmark remains the loss of active DIP extension. Additionally, the DIP is typically immobilized in extension during treatment, not flexion.