Electra Trapezio Metacarpal Prosthesis: Results of the First 100 Cases

Abstract

The Elektra trapeziometacarpal prosthesis is a cementless, unconstrained prosthesis made by Fixano with titanium and chrome-cobalt steel. This paper examines the results of the first 100 prostheses used by the author for one indication only, viz. painful trapeziometacarpal osteoarthritis. The average follow-up period was 54 (range 36-78) months. Studies of pain, mobility and grip and pinch strength were carried out, the results of which were good in 83 cases. Seven dislocations occurred. Five of these were following severe trauma. The commonest complication was a lack of osteointegration of the trapezial part of the prosthesis, which occurred in 15 cases. Sinking into the metacarpal of the distal stem occurred early in the series in two cases. Some others complications were observed: allergy to the metal (one case), fracture after direct trauma of the thumb (one case) and very painful osteoarthritis of the scaphotrapeziotrapezoid joint (one case).

Prospective 1-Year Follow-Up Study Comparing Joint Prosthesis With Tendon Interposition Arthroplasty in Treatment of Trapeziometacarpal Osteoarthritis

“…Previously, this prosthesis has only been evaluated by the inventor in a report presenting the results of his first 100 patients with an average follow-up period of 54 months. 30 Parameters of pain, ROM, and strength were improved by the joint prosthesis, and the overall success rate was 83%. The major complication was lack of osteointegration of the trapezial cup, resulting in aseptic loosening in 15 patients.…”

“…31 Operative techniques Joint prosthesis surgery: An unconstrained, cobalt-chromium/titanium, hydroxyapatite-coated trapeziometacarpal joint prosthesis (Elektra) was implanted using cementless, press-fit technique as described previously. 30 In brief, the osteoarthritic joint-bearing metaphysis of the metacarpal bone was resected, and manual reaming of the medullar canal was performed until stable cortical bone contact was achieved. The hydroxyapatite-coated metacarpal stem was gently impacted into the metacarpal canal until its beveled edge was flush with the surface of the osteotomy.…”

“…In 2006, the inventor of the Elektra prosthesis reported on the first 100 patients with a mean follow-up period of 53 months. 30 He demonstrated improvements of strength, range of motion (ROM), and pain relief. However, in 15% of the patients, loosening of the cup was reported (93% of cases with nonfixation of the cup developed within the first 9 months postoperatively).…”

Trapeziometacarpal osteoarthritis: pyrocarbon interposition implants

“…Since this treatment showed poor outcomes and a high rate of complications, as reported in several studies (12)(13)(14)(15), this procedure was limited to low-demand patients affected by rheumatoid arthritis (16). This kind of prosthesis was followed by the development of several metal total joint implants (ball-andsocket prostheses) which showed good results (17). However, the main problem with these implants was radiographic loosening of the trapezial component (18,19).…”

Early Outcomes of Pyrolytic Carbon Hemiarthroplasty for the Treatment of Trapezial-Metacarpal Arthritis

“…11 Steel metal-on-metal prostheses provided a good alternative, demonstrating durability; however, aseptic loosening, particulate wear, and metal allergies remained a problem. 12 Pyrolytic carbon, in comparison with previous prostheses, is a synthetic material developed in the 1960s. Pyrolytic carbon has an elastic modulus that is similar to that of cortical bone, which aids in dampening stresses at the bone-prosthetic interface and enhances biological fixation.…”