Risk factors for nonunion of ulnar styloid fractures associated with distal radius fractures

Year 2025, Volume: 11 Issue: 4, 683 - 688, 04.07.2025

Emre Kaya , Nurtaç Alper Akdemir , Ali Geçer , Levent Konukoğlu

https://doi.org/10.18621/eurj.1663265

Abstract

Objectives: A major complication of ulnar styloid fractures (USFs) associated with displaced distal radius fractures (DRFs) is nonunion, which can result in pain and instability of the distal radioulnar joint (DRUJ). This study aimed to identify the risk factors influencing the healing of USFs in cases of displaced DRFs, when treated using different methods - either surgically with plate-screw fixation, or conservatively with closed reduction and a plaster cast.

Methods: A total of 41 patients with USFs associated with DRFs, treated either surgically or conservatively, were retrospectively evaluated. Fractures were classified based on the treatment modality (surgical/conservative), demographic data, and radiographic characteristics. The Fernandez classification system was used to categorize DRFs. USF displacement was stratified into two groups: displacement >2 mm and <2 mm. Union and nonunion rates were compared across all parameters.

Results: Of the 41 cases included, 12 DRFs were managed surgically with plate-screw fixation, while 29 were treated conservatively with closed reduction and casting. Union was achieved in 35 cases, whereas nonunion was observed in 6. A statistically significant correlation was found between USF displacement >2 mm and nonunion. No significant association was observed between nonunion and other variables, including treatment modality, age, sex, laterality, or fracture classification.

Conclusions: The development of nonunion in USFs accompanying DRFs is not significantly influenced by treatment modality, age, sex, fracture classification, or side of involvement. However, a displacement of the USF greater than 2 mm is associated with a significantly increased risk of nonunion.

Keywords

Ulnar styloid fractures , distal radius fractures , fracture healing , radioulnar joint , risk factors

Ethical Statement

This study was approved by the Haydarpaşa Numune Training and Research Hospital Non-Interventional Clinical Research Ethics Committee (Decision no. HNEAH-GAEK/KK/2924/150, Date: 19.11.2024).

References

• 1. Shaw JA, Bruno A, Paul EM. Ulnar styloid fixation in the treatment of posttraumatic instability of the radioulnar joint: a biomechanical study with clinical correlation. J Hand Surg Am. 1990;15(5):712-720. doi: 10.1016/0363-5023(90)90142-e.
• 2. Nicolaidis SC, Hildreth DH, Lichtman DM. Acute injuries of the distal radioulnar joint. Hand Clin. 2000;16(3):449-459.
• 3. May MM, Lawton JN, Blazar PE. Ulna styloid fractures associated with distal radius fractures: incidence and implications for distal radioulnar joint instability. J Hand Surg Am. 2002;27(6):965-971. doi: 10.1053/jhsu.2002.36525.
• 4. Ayalon O, Marcano A, Paksima N, Egol K. Concomitant ulna styloid fracture and distal radius fracture Portend Poorer Outcome. Am J Orthop (Belle Mead NJ). 2016;45(1):34-37.
• 5. Yilmaz S, Cankaya D, Karakus D. Ulna styloid fracture has no impact on the outcome but decreases supination strength after conservative treatment of distal radial fracture. J Hand Surg Eur Vol. 2015;40(8):872-873. doi: 10.1177/1753193415583067.
• 6. Belloti JC, Moraes VY, Albers MB, Faloppa F, Dos Santos JB. Does an ulna styloid fracture interfere with the results of a distal radius fracture? J Orthop Sci. 2010;15(2):216-222. doi: 10.1007/s00776-009-1443-7.
• 7. Daneshvar P, Chan R, MacDermid J, Grewal R. The effects of ulna styloid fractures on patients sustaining distal radius fractures. J Hand Surg Am. 2014;39(10):1915-1920. doi: 10.1016/j.jhsa.2014.05.032.
• 8. Walenkamp MM, de Muinck Keizer RJ, Goslings JC, Vos LM, Rosenwasser MP, Schep NW. The Minimum Clinically Important Difference of the Patient-rated Wrist Evaluation Score for Patients With distal radius fractures. Clin Orthop Relat Res. 2015;473(10):3235-3241. doi: 10.1007/s11999-015-4376-9.
• 9. Lindau T, Hagberg L, Adlercreutz C, Jonsson K, Aspenberg P. Distal radioulnar instability is an independent worsening factor in distal radial fractures. Clin Orthop Relat Res. 2000;(376):229-235. doi: 10.1097/00003086-200007000-00031.
• 10. Abid A, Accadbled F, Kany J, de Gauzy JS, Darodes P, Cahuzac JP. Ulna styloid fracture in children: a retrospective study of 46 cases. J Pediatr Orthop B. 2008;17(1):15-19. doi: 10.1097/BPB.0b013e3282f3cacb.
• 11. Burgess RC, Watson HK. Hypertrophic ulnar styloid nonunions. Clin Orthop Relat Res. 1988;(228):215-217.
• 12. Hauck RM, Skahen J 3rd, Palmer AK. Classification and treatment of ulnar styloid nonunion. J Hand Surg Am. 1996 May;21(3):418-422. doi: 10.1016/S0363-5023(96)80355-8.
• 13. Protopsaltis TS, Ruch DS. Triangular fibrocartilage complex tears associated with symptomatic ulnar styloid nonunions. J Hand Surg Am. 2010;35(8):1251-1255. doi: 10.1016/j.jhsa.2010.05.010.
• 14. Kim JK, Yun YH, Kim DJ, Yun GU. Comparison of united and nonunited fractures of the ulnar styloid following volar-plate fixation of distal radius fractures. Injury. 2011;42(4):371-375. doi: 10.1016/j.injury.2010.09.020.
• 15. Tsukazaki T, Iwasaki K. Ulnar wrist pain after Colles' fracture. 109 fractures followed for 4 years. Acta Orthop Scand. 1993;64(4):462-464. doi: 10.3109/17453679308993668.
• 16. Nakamura R, Horii E, Imaeda T, Nakao E, Shionoya K, Kato H. Ulnar styloid malunion with dislocation of the distal radioulnar joint. J Hand Surg Br. 1998;23(2):173-175. doi: 10.1016/s0266-7681(98)80168-x.