Journal of shoulder and elbow surgery | 2021
Coronal Shear Fractures of the Distal Humerus Treated According to the Modified Dubberley Classification System.
Abstract
BACKGROUND\nCoronal shear fractures of the capitellum and trochlea are relatively uncommon and can be challenging to treat because of variable articular comminution and poor bone stock. Classification is valuable to help guide surgical decision making and prognosis. The aim of this study was to present a large series of coronal shear fractures treated according to the Modified Dubberley Classification System (MDCS).\n\n\nMETHODS\n45 patients with a coronal shear fracture were followed up (12-93 months, mean 28 months) after surgical intervention. Fractures were classified according to the MDCS by 3 observers and outcome data collected included Oxford Elbow Score (OES), Visual Analogue Pain Score (VAS), range of motion (ROM), complications, and radiographic findings.\n\n\nRESULTS\nThere were 10 type 1; 12 type 2; 8 type 3 and 15 type 4 fractures. There were 26 subtype B fractures (posterior comminution). 37 patients had open reduction and internal fixation (ORIF) and 8 underwent primary arthroplasty. The median OES and VAS were 43(16-48) and 2 (0-9) respectively. Median flexion extension arc was 125° (range 70°-140°). There was no significant difference in OES, VAS or ROM according to fracture type (type 1-4) subtype (type a or b) or treatment method (arthroplasty vs. ORIF). The overall complication and re-operation rates were 31% and 33% respectively. 75% of complications occurred in type 3 and 4 fractures and there was a non-significant trend towards higher complication rate in type B fractures than type A fractures (34% vs. 16%, p=0.19). Patients with a type B fracture who underwent screw only fixation had a significantly lower OES and higher complication rate compared to when they had combined plating with screws (OES, p = 0.03; complications p=0.04) and compared to when an arthroplasty was performed (OES, p=0.05; complications p=0.04).\n\n\nCONCLUSION\nConsistently good outcomes can be achieved by classification and management according to the MDCS. It is recommended that type B fractures undergo combined plate and screw fixation and that type 4 fractures should be considered for arthroplasty because of the higher risk of complications with ORIF.