Anatomy of Lister's Tubercle: Implications for Volar Locked Plating of the Distal Radius.

BACKGROUND

Determining accurate intraoperative screw length in complex distal radius fractures may pose difficulties. With volar plate fixation, excessive screw length may result in extensor pollicis longus injury and this can be challenging to determine via intraoperative imaging. This study aims to identify the precise anatomic location and parameters of Lister's tubercle on the dorsal aspect of the radius.

METHODS

The anatomy and location of Lister's tubercle was evaluated in 26 cadaveric arms, of which 27% were female, with a mean age of 73.6 years. Additionally, Lister's tubercle was evaluated on 198 computed tomography (CT) scans using a quantitative distal radius surface map. Median age was 28 years, and 28% of the patients were female.

RESULTS

As measured in cadaveric arms, the mean Lister's tubercle length was 12.6 mm, and width was 5.4 mm. The distance from the radial styloid to the distal and proximal border of Lister's tubercle averaged 23.0 and 10.4 mm, respectively. Of the total distal radial width, Lister's tubercle begins 43% from the radial border and spans to 42% of the ulnar border, encompassing 16% of the entire width of the dorsal distal radius. On CT mapping, the distance between the peak of Lister's tubercle and the ulnar and radial border of the radius was 46% and 54%, respectively. Female sex was associated with a smaller distal radius width, but not with a smaller Lister's tubercle.

CONCLUSIONS

Knowledge of Lister's tubercle anatomy may assist in more precise screw placement in volar locked plating of distal radius fractures.

LEVEL OF EVIDENCE

IV-Therapeutic.