Evaluation of thirty eight cemented pegged glenoid components with variable backside curvature: two-year minimum follow-up.

Background: The PERFORM™ pegged glenoid system has been used for shoulder arthroplasty since 2012. This system offers multiple backside curvatures per size to better match variable patient anatomy. As a result, less reaming is required and subchondral bone is preserved-a critical factor in preventing glenoid migration and loosening, thus enhancing implant longevity.

Purpose: The purpose of this study was to analyze all radiographic modifications around this new glenoid implant.

Method: Thirty-eight shoulders which received the PERFORM™ pegged glenoid component between June 2012 and January 2014 for primary or secondary osteoarthritis were reviewed at two-years minimum follow-up. There were 13 men and 22 women with an average age of 67 years. Humeral components were an uncemented short stem implant in nine (23%) and a resurfacing implant in 29 (77%).

Results: At 27-months average follow-up (24-41), Constant score improved from 30 to 65 points. Range of motion improved significantly at follow-up from 100° to 142° for the anterior elevation, and from 15 to 40° for the external rotation. Radiographic lucent lines (RLL) were observed post-operatively in eight cases (21%), and in 16 cases (42%) at the last follow-up with an increase of the RLL score from 0.36 ± 0.8 to 1.3 ± 2 (p < 0.001) without signs of loosening (RLL > 12). One revision has been performed after anterior shoulder dislocation, rotator cuff tear and glenoid component migration. RLL score was not correlated with dominant side, sex, age, or Constant score.

Discussion-conclusion: The cemented pegged glenoid component with multiple backside curvatures gave satisfactory results at two-years minimum follow-up for up to three years with a low RLL score. Long-term studies are mandatory to confirm these results.