Surgical Indications for Base of Fifth Metacarpal Fractures
Surgical intervention is indicated for base of fifth metacarpal fractures when there is intra-articular displacement of any degree, as these fractures are inherently unstable and require anatomic restoration of the articular surface. 1
Absolute Indications for Surgery
The following criteria mandate surgical fixation:
- Any intra-articular displacement or step-off - These fractures cannot maintain reduction with conservative treatment and will lead to post-traumatic arthritis and functional disability if not surgically addressed 1, 2
- Joint displacement present on imaging - Even minimal articular incongruity requires surgical reduction 3, 4
- Malrotation of the digit - Any rotational deformity is unacceptable and requires operative correction 3, 4
- Angulation >30 degrees - Displacement beyond this threshold will not respond adequately to closed reduction 3, 4
- Shortening >5 mm - Excessive shortening compromises hand function and requires surgical stabilization 3, 4
Additional Surgical Indications
- Open fractures - All open fractures of the fifth metacarpal base require surgical debridement and fixation 3, 4
- Multiple metacarpal fractures - Serial fractures involving multiple metacarpal bones necessitate operative stabilization 3, 4
- Comminuted fractures - Severe fragmentation typically requires open reduction with multiple K-wire fixation to restore articular congruity 1, 2
- Failed closed reduction - When adequate restoration of the articular surface cannot be achieved with closed manipulation, open reduction with plate fixation should be performed 2
Surgical Technique Selection
Attempt closed reduction with percutaneous K-wire fixation first for all intra-articular fractures; reserve open reduction with locking plate fixation for cases where closed reduction fails to achieve adequate articular restoration. 2
- Percutaneous pinning after closed reduction is appropriate for simple fractures and some comminuted patterns when articular congruity can be restored closed 1, 2
- Open reduction with plate fixation should be performed when closed reduction cannot adequately address intra-articular step-off or in severely comminuted fractures 2
- Both techniques achieve satisfactory outcomes with >90% grip strength recovery and nearly full range of motion when properly indicated 2
Critical Pitfalls to Avoid
- Do not rely on closed reduction alone for displaced fifth metacarpal base fractures - These are inherently unstable and will lose reduction, resulting in pain, functional disability, and osteoarthritic changes 1
- Do not accept any degree of intra-articular displacement - Even minimal articular incongruity leads to post-traumatic arthritis 1, 2
- Do not use cast immobilization as definitive treatment for unstable fractures - Conservative management fails in displaced base fractures 3, 4
Expected Outcomes
When surgical indications are properly followed with anatomic reduction and stable fixation, patients achieve:
- Complete osseous union in all cases 2
- Satisfactory functional outcomes with Disabilities of the Arm, Shoulder, and Hand scores indicating minimal disability 2
- Grip strength >90% compared to the contralateral side 2
- Nearly full total active motion of the little finger 2
- Low rates of clinically significant post-traumatic arthritis (grade 1 changes only) 2