Ulnar-Styloid Nonunion and Partial Rupture of Extensor Carpi Ulnaris Tendon: Two Case Reports and Review of the Literature

Abstract

Two unusual cases of symptomatic partial rupture of the extensor carpi ulnaris tendon associated with ulnar-styloid nonunion are described. Intraoperative findings suggested that the jagged surface of the distal ulna was the cause of flaying. In one case, debridement of the frayed extensor carpi ulnaris tendon and fixation of the ulnar styloid were effective for the relief of symptoms. But after the same procedure in another case, osteosynthesis of the ulnar-styloid could not be attained and tenodesis of the extensor carpi ulnaris tendon to the ulnar head was needed. Partial rupture of the ECU tendon should be taken into account in the differential diagnosis of a patient with ulnar wrist pain after ulnar-styloid fracture.

The management of distal ulnar fractures in adults: a review of the literature and recommendations for treatment

“…There are a number of reasons why a non-united ulnar styloid fracture can become symptomatic: It can be responsible for a non-functioning ulno-radial ligament (peripheral TFCC detachment) [27] (Fig. 6), cause impingement of the overlying ECU tendon [28], abut on the carpus [27, 29] (Fig. 7) or be an irritative loose body [27] (Fig.…”

“…The ulnar styloid nonunion should be treated as a bony nonunion and be reattached to the ulnar head if the fragment is large [27], [28] (Fig. 9).…”

“…If the fragment is small, it should be shelled out and the ulno-radial ligament should be reattached directly to the fovea of the ulnar head [27]. Patients treated in this way have been reported to have good to excellent results [27, 28]. If there is no DRU-joint instability the ulnar styloid can be shelled out without any associated ligament procedure [21, 27, 31].…”

MR Imaging of Trauma: Elbow and Wrist

“…32 Subluxation, dislocation, or tears of the ECU may complicate fractures of the ulnar styloid. 33 Flexor and extensor tendon injuries are more often secondary to an underlying inflammatory arthropathy or overuse syndrome. MR imaging demonstrates tendon thickening, increased intrasubstance signal, fluid in the tendon sheath, and soft tissue edema and thickening.…”

Fixing fractures of the ulnar styloid in distal radius fractures

“…Extensor carpi ulnaris tendon impingement caused by malalignment of a fibrous nonunion may also be responsible for a poor clinical outcome. [ 13 , 14 ]. This condition is rarely found after a distal radius fracture and it is successfully treated with excision of the bony prominence and reconstruction of the floor of the sixth compartment.…”