Which are common management options for a Bennet fracture?

• A. Immobilization in a thumb spica cast
• B. Joint replacement
• C. Observation only
• D. Wrist fusion

Answer: (D)

Bennet fractures involve the base of the first metacarpal at the thumb carpometacarpal (CMC) joint, so treatment aims to keep that joint surfaces aligned during healing and prevent instability. For fractures that are not displaced or are only minimally displaced, immobilizing the thumb and wrist in a thumb spica cast provides stability and allows the fracture to heal without surgical intervention. When a fracture is displaced or unstable, the usual approach is surgical fixation to restore articular congruity, but among the given options, immobilization in a thumb spica cast best reflects the common conservative management. Options like joint replacement or wrist fusion target different joints or conditions and are not standard acute treatments for a Bennet fracture. Observation alone is generally insufficient if there is any displacement or instability, because loss of alignment can lead to chronic subluxation and arthritis.