Look for the POLESTAR (POsteroLateral Engagement of Soft Tissue And Radial head) while navigating around elbow dislocation

Abstract

Background: Elbow dislocation is frequently associated with bony and osteochondral posterolateral capitellar lesions that are often under-reported. We aim to examine the radiologic signs of posterolateral lesions on computed tomography (CT).

Methods: A retrospective analysis of CT scans was performed. Patients were classified into 4 groups: (1) simple elbow dislocation, (2) elbow dislocation with a fracture of the coronoid tip, (3) elbow dislocation with coronoid tip fracture and a radial head fracture inferior or equal to the anterior third, and (4) terrible triad defined as elbow dislocation with concomitant coronoid and radial head fracture with a more important involvement. Patients with a more complex fracture pattern were excluded. The presence of POsteroLateral Engagement of Soft Tissue And Radial head (POLESTAR) patterns was analyzed and subclassified as impaction type or fragmentation type.

Results: Fifty-one CT scans met the inclusion criteria. POLESTAR lesions were identified in 48 cases (94%): 46% impaction-type and 54% fragmentation-type POLESTAR. Analyzing patients from grade 1 to 4, impaction-type POLESTAR was found, respectively, from 40% to 57%, whereas fragmentation type was present from 60% to 43%.

Conclusions: This study shows a high incidence of POLESTAR lesions (94%) that can be present as impaction type or fragmentation type. Based on our preliminary results, impaction type is more common in grades 3 and 4, whereas fragmentation type is more frequent in grades 1 and 2.

Keywords: CT scan; dislocation; elbow; fracture; lesions; radial head; soft tissue.