Background Open or arthroscopic partial resection of the elongated ulnar styloid is the surgical treatment of choice for ulnar styloid impaction syndrome.Case Description A patient with a severely elongated processus styloideus ulnae (PSU) with a chronic impaction of the distal-radial margin against the triquetrum suffered a traumatic triangular fibrocartilage complex (TFCC) Palmer 1B rupture and DRUJ instability. The length of the PSU was 9mm. After failed conservative treatment, a partial oblique arthroscopic resection of the PSU and simultaneous TFCC reinsertion were performed with uneventful recovery.

Literature Review Arthroscopic resection has emerged as an alternative to the traditional open PSU resection for the treatment of styloid impaction syndrome. A transverse resection is described as the treatment of choice. Regarding the extent of resection subtotal ligament sparing resection or resection to the lower margin have been suggested.

Clinical Relevance Surgical planning of PSU resection should take into consideration the anatomy of the impingement. The extent of resection should be planned individually, and sometimes an oblique resection may be the preferred option.