What is the treatment for an ulnar styloid fracture?

Treatment of Ulnar Styloid Fractures

Most ulnar styloid fractures associated with distal radius fractures should be treated conservatively without surgical fixation, as they do not significantly affect functional outcomes regardless of union status. 1, 2

Primary Treatment Approach

Conservative (non-operative) management is the standard treatment for the majority of ulnar styloid fractures. The key decision point is whether the distal radioulnar joint (DRUJ) remains stable after the radius fracture is addressed 1, 3, 4:

When Conservative Treatment is Appropriate:

• Undisplaced ulnar styloid fractures should be managed non-operatively 5
• Asymptomatic nonunions do not require surgical intervention 5
• Stable DRUJ after radius fixation - even with base fractures, conservative treatment provides equivalent long-term outcomes to surgery 3, 4
• Both tip and base fractures when the DRUJ is stable can be left untreated without affecting patient outcomes 2

Evidence Supporting Conservative Management:

The most compelling recent evidence shows:

• No difference in functional outcomes at 1 year whether ulnar styloid fractures are present or absent, treated or untreated, united or nonunited 2
• In a prospective study of 134 surgically treated distal radius fractures, 52% had concomitant ulnar styloid fractures; 76% remained nonunited at 1 year, yet there was no statistical difference in QDASH scores (6.7 vs 8.4, p=0.47) or PRWE scores (4.8 vs 7.5, p=0.24) between patients with and without ulnar styloid fractures 2
• Better wrist function at 6 months with non-surgical treatment compared to operative fixation 3
• Higher complication rates with surgical fixation (OR 14.3) 3

When Surgical Treatment is Indicated

Surgery should be reserved for the minority of cases with persistent DRUJ instability after radius fixation. 3, 4

Specific Surgical Indications:

• Displaced fractures with DRUJ instability confirmed by intraoperative ballottement testing after radius fixation 5, 3
• Type 2 nonunions (associated with DRUJ subluxation) that are symptomatic 6
• Large base fragments (>2mm articular step-off) with documented instability 1, 6

Surgical Options Based on Fragment Size:

• Large fragments with DRUJ instability: Open reduction and internal fixation (tension band wiring or angle-stable hook plate) 5, 6
• Small fragments with DRUJ instability: Fragment excision with triangular fibrocartilage complex (TFCC) repair to the distal ulna 6

Clinical Decision Algorithm

1. First, adequately treat the distal radius fracture 1
2. Assess DRUJ stability after radius fixation using ballottement testing 3, 4
3. If DRUJ is stable: No treatment of ulnar styloid fracture needed, regardless of fracture location or displacement 1, 2, 4
4. If DRUJ remains unstable: Consider surgical fixation or TFCC repair 3, 4, 6

Important Caveats

• The 75% nonunion rate with conservative treatment does not correlate with worse outcomes 2
• Routine fixation is not indicated as standard of care 3
• Conservative treatment requires average 6.6 weeks of supination sugar-tong splinting for DRUJ instability cases 4
• Surgical complications include higher infection risk and the need for hardware removal 3
• Long-term outcomes are equivalent between conservative and operative treatment when DRUJ stability is achieved 4

Management of Symptomatic Nonunions

For established symptomatic nonunions presenting later:

• Type 1 (stable DRUJ): Simple excision of the fragment provides satisfactory pain relief 6
• Type 2 (unstable DRUJ): Requires TFCC reconstruction with either fragment fixation (if large) or excision with TFCC repair 6