**Core Concept**
Mallet finger is a type of finger injury where the extensor tendon of the distal interphalangeal (DIP) joint is torn, causing an inability to actively extend the DIP joint. This injury often occurs when a person tries to catch a ball or object with their finger, resulting in forced flexion of the DIP joint.

**Why the Correct Answer is Right**
In the case of a suspected mallet finger injury with normal X-rays, the most appropriate management is to splint the DIP joint in extension to prevent further flexion and allow for healing of the extensor tendon. This can be achieved with a dorsal splint, which is a type of splint that is placed on the back of the finger to immobilize the DIP joint in extension. The splint should be worn for 6-8 weeks to allow for adequate healing of the tendon.

**Why Each Wrong Option is Incorrect**
**Option A:** Immediate surgical intervention is not typically indicated for a suspected mallet finger injury with normal X-rays. Surgery may be necessary in cases where the tendon is severely damaged or if there is a delay in seeking medical attention.

**Option B:** A dorsal splint is the preferred method of immobilization for a suspected mallet finger injury, not a buddy taping method where the injured finger is taped to an adjacent finger.

**Option C:** A mallet finger injury does not typically require a period of immobilization in flexion, as this would exacerbate the injury by preventing the tendon from healing in its normal anatomic position.

**Option D:** A mallet finger injury is not typically managed with a cast, as this would be too restrictive and may lead to stiffness in the involved finger.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that mallet finger injuries can often be managed conservatively with a dorsal splint, but if there is any suspicion of a more severe injury or if the patient is not improving with conservative management, surgical evaluation should be considered.

**Correct Answer:** B. Buddy taping