Ulnar styloid impaction syndrome refers to wrist pain due to a long ulnar styloid process impacting upon the triquetral bone.
An ulnar styloid >6 mm in length is commonly regarded as being long. Impaction results in chondromalacia of the opposing articular surfaces, i.e. the proximal pole of the triquetral bone and ulnar styloid tip.
Treatment and prognosis
Surgical removal of the ulnar styloid process can effectively treat the condition.
A similar but distinct impaction syndrome due to non-union of the ulnar styloid (commonly following fracture) can also occur. This syndrome more commonly involves disruption of the TFCC complex.
- 1. Cerezal L, del Piñal F, Abascal F et-al. Imaging findings in ulnar-sided wrist impaction syndromes. Radiographics. 22 (1): 105-21. Radiographics (full text) [pubmed citation]
- 2. Zahiri H, Zahiri CA, Ravari FK. Ulnar styloid impingement syndrome. (2010) International orthopaedics. 34 (8): 1233-7. doi:10.1007/s00264-010-0969-9 - Pubmed
- 3. Luis Cerezal, Francisco del Piñal, Faustino Abascal, Roberto García-Valtuille, Teresa Pereda, Ana Canga. Imaging Findings in Ulnar-sided Wrist Impaction Syndromes1. (2002) RadioGraphics. 22 (1): 105-21. doi:10.1148/radiographics.22.1.g02ja01105 - Pubmed
Related Radiopaedia articles
- wrist fractures and dislocations
- distal radial fracture
- carpal bones
- carpal instability
- triangular fibrocartilaginous complex (TFCC) injuries
- ulnar-sided wrist impaction and impingement syndromes
- soft tissue and tendons