Radiographic Risk Factors for Flexor Tendon Ruptures Following Distal Radius Volar Plating.

PURPOSE: To identify radiographic risk factors for flexor tendon ruptures following volar distal radius plating.

METHODS: This was a case-control study of 27 patients with complete flexor tendon rupture following volar plating of distal radius fractures and 73 control patients who underwent volar plating and did not rupture. Demographic and radiographic parameters were recorded including radial inclination, Soong class, lateral carpal alignment using the capitate-to-axis-of-radius distance (CARD), and volar tilt. Univariable and multivariable logistic regression modeling were used to determine independent predictors of rupture.

RESULTS: The rupture group consisted of 25 females and 2 males. The mean age at flexor tendon rupture was 66.9 years. When radiographic variables were included in the multivariable model, analysis revealed that CARD was the only significant predictor of tendon rupture when a plate was prominent. The mean CARD for the rupture group was 9.8 mm, with a range of 4.9-20 mm. The mean CARD for the control group was 3.5 mm, with a range of -2.9 mm to 11.6 mm.

CONCLUSION: In this analysis, CARD was the strongest predictor of attritional flexor tendon rupture in the setting of a prominent volar plate. Intraoperative correction of lateral carpal alignment based on CARD may decrease the risk of flexor tendon rupture when the plate is prominent.

TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.