Computed Tomography Evaluation of Distal Screw Penetration in Volar Locking Plate Fixation for Intra-Articular Distal Radius Fractures.

ABSTRACT

PURPOSE: Volar locking plate fixation for distal radius fractures (DRFs) is a technically demanding procedure with a risk of distal screw penetration through the dorsal cortex or the articular surface. This study aimed to investigate the incidence and details of distal screw penetration after volar locking plate fixation for intra-articular DRFs using a CT scan and to evaluate the relationship between the incidence of screw penetration and fracture comminution severity and the clinical complications of screw penetration. METHODS: This was a retrospective case series of 91 adult patients (mean age, 63 years; 27 men) who underwent volar locking plate fixation for intra-articular DRFs from 2015 to 2018. The positioning of the distal screws was evaluated using a postoperative CT scan, and radiological outcomes were compared between the AO C1 and C3 groups. At the final follow-up, tendon rupture and arthritis severity were assessed as clinical complications of dorsal and intra-articular screw penetration. RESULTS: Distal screw penetration was observed in 44 wrists (48%), dorsal cortex screw penetration in 34, intra-articular screw penetration in 13, and both dorsal cortex and intra-articular screw penetration in three. The incidence of intra-articular screw penetration was significantly higher in the C3 group than in the C1 group. No tendon rupture was observed. Multivariable analysis revealed that intra-articular screw penetration was significantly related to high severity of arthritis. CONCLUSIONS: Approximately half of the study patients with intra-articular DRFs had distal screw penetration. The incidence of intra-articular screw penetration was associated with the severity of fracture comminution, and the intra-articular screw penetration was associated with the incidence of early radiocarpal arthritis. Intra-articularly penetrating screws should be replaced as soon as they are discovered, regardless of the length of penetrated screw or absence of patients' subjective symptoms. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic IV.