Revision options for discontinued trapeziometacarpal arthroplasties: compatibility with currently available implants.

Abstract

Surgical revision options for failed trapeziometacarpal total joint replacement include implant replacement and trapeziectomy. However, discontinuation of older implants complicates revision with original components, particularly as removing a well-fixed metacarpal stem can be challenging. This study examined the feasibility of pairing discontinued stems (Arpe, Elektra and Ivory) with currently available necks (Maïa, Moovis and Touch). We analysed the metallurgical composition, insertion depth, contact surface area and mechanical stability for all possible combinations of these implants. Our findings show compatibility of both Ivory and Arpe stems with the Touch neck and of the Elektra stem with the Moovis neck. Under strict lateral loading, fixation was stable up to 826.87 N, surpassing <i>in vivo</i> forces. Microscopic evaluation after the biomechanical load-to-failure test showed negligible damage to the connecting surfaces. These results suggest that it is safe to pair discontinued stems with currently available necks in revision trapeziometacarpal total joint arthroplasty.