During fixation of Bennett’s fracture, which muscle hinders it?
**Core Concept**
Bennett's fracture is a type of intra-articular fracture of the base of the first metacarpal bone in the thumb. The fixation of Bennett's fracture involves stabilizing the fracture fragments to promote healing. However, the anatomy of the thumb and surrounding muscles can hinder this process.
**Why the Correct Answer is Right**
The muscle that hinders the fixation of Bennett's fracture is the abductor pollicis longus (APL). The APL muscle inserts on the base of the first metacarpal bone and the distal radius, allowing it to abduct the thumb. When the thumb is in a position of abduction, the APL muscle can pull the fracture fragments apart, hindering the fixation of Bennett's fracture.
**Why Each Wrong Option is Incorrect**
**Option A:** The flexor pollicis longus (FPL) muscle is not directly involved in the fixation of Bennett's fracture, as it primarily controls flexion of the thumb.
**Option B:** The extensor pollicis brevis (EPB) muscle, while involved in thumb extension, is not the primary muscle that hinders the fixation of Bennett's fracture.
**Option C:** The adductor pollicis muscle, which adducts the thumb, is not typically involved in the fixation of Bennett's fracture.
**Clinical Pearl / High-Yield Fact**
To successfully fix Bennett's fracture, the surgeon must take into account the anatomy of the thumb and the surrounding muscles, particularly the abductor pollicis longus. A thorough understanding of the thumb's musculature is essential to ensure proper fixation and promote healing.
**Correct Answer: D. Abductor pollicis longus**