Abstract
Aims: The purpose of this study is to compare the radiographic results of two different glenoid component designs by analyzing the radiolucent lines (RLL).
Methods: Sixty-three shoulder arthroplasties with primary osteoarthritis were divided into two groups based on glenoid component type: thirty-five shoulders with flat back, and thirty-one shoulders with convex back, polyethylene glenoid implants. The radiolucenct lines were analyzed on fluoroscopically positioned, postoperative AP radiographs. The RLL Score (RLLS) was calculated using the technique of Molé. The RLLS was compared between the two groups.
Results: On the immediate postoperative radiographs the average of total RLL score was 1.67 in Group 1 and 0.98 in Group 2 (p< 0.0005). There was a statistically significant association between the type of implant and the incidence of radiolucency behind the faceplate as well (p< 0.0005). On the 2-year postoperative radiographs the average RLL score was 4.19 in the Group1 (2.86 under the tray, and 1.33 around the keel), and 3.23 in Group2 (p=0.02) (2.09 under the tray, and 1.14 around the keel). The radiolucency behind the face-plate (p< 0.0005) was significantly greater in the flat back group, but not around the keel (p=0.427). There was no significant difference between the two groups regarding the degree of RLL score progression.
Conclusions: The initial and mid-term RLLS is better with convex than fl at back glenoid component.
Theses abstracts were prepared by Professor Dr. Frantz Langlais. Correspondence should be addressed to him at EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
