The Presence and the Location of an Ulnar Styloid Fracture Associated With Distal Radius Fracture Predict the Presence of Triangular Fibrocartilage Complex 1B Injury

Purpose

To investigate the correlation between ulnar styloid fracture (USF) associated with distal radius fracture (DRF) and triangular fibrocartilage complex (TFCC) injuries and to elucidate whether the presence or location of an USF in a patient with DRF predicts the presence of traumatic TFCC injuries.

Methods

From 2005 to 2018, an arthroscopic evaluation was performed to detect TFCC injuries associated with DRF. The presence and location of USFs were evaluated using computed tomography. TFCC injuries were classified in accordance with Palmer's classification. All wrists were divided into group A (DRF without USF) and group B (DRF with USF). The incidence of TFCC injuries in the 2 groups was compared. group B was then divided into 2 subgroups in accordance with the USF location: the tip or middle fracture subgroup and the base fracture subgroup. Data were analyzed with significance set at P < .05.

Results

One hundred thirty-eight patients were enrolled in this study. Group A included 42 wrists in 42 patients, whereas group B included 96 wrists in 96 patients. There were significant differences between the 2 groups regarding the incidence of traumatic TFCC injuries (P = .036) and TFCC 1B injury (P = .002), although there were no differences between the 2 groups regarding age, sex, injured side, direction of displacement, and type of DRF. Within group B, the tip and middle fracture subgroup included 37 wrists in 37 patients, whereas the base fracture group included 59 wrists in 59 patients; a significant difference was observed between the two subgroups regarding the incidences of TFCC 1B injuries (P = .044).

Conclusions

The presence of USF associated with DRF predicted the presence of frequently occurring traumatic TFCC injury and TFCC 1B injury. Moreover, the location of USFs was a predictive factor for TFCC 1B injury in adults with DRF. On the other hand, traumatic TFCC injury had occurred in adults with DRF, regardless of the presence of USF.

Level of evidence

Level IV, Case series.