Flexible Hinge Silicone Implant with or without Titanium Grommets for Arthroplasty of the First Metatarsophalangeal Joint

Abstract

To review outcomes of 37 patients who underwent arthroplasty of the first metatarsophalangeal joint using flexible hinge silicone implants with or without titanium grommets. 36 women and one man (63 feet) underwent arthroplasty of the first metatarsophalangeal joint for rheumatoid arthritis (RA) using Swanson flexible hinge silicone toe implants with or without titanium grommets. 20 women (35 feet) aged 31 to 72 (mean, 52) years with Steinbrocker grade II (n=4), grade III (n=6), and grade IV (n=10) RA of the feet were treated with the implant without grommets, whereas 16 women and one man (28 feet) aged 48 to 73 (mean, 60) years with Steinbrocker grade III (n=4) and grade IV (n=13) RA of the feet were treated with the implant with grommets. Pain levels were self-rated. Degenerative changes and the presence of osteophytes or deformity were recorded, as were breakage or deformation of the implants, radiolucencies around the implant, implant loosening, silicone-induced synovitis, and sclerosis around the implant. All patients reported pain relief from severe to mild or moderate. Respectively for the feet with and without grommets, the rates of implant deformation were 25% and 63% (p=0.031), whereas the rates of moderate-to-severe radiolucencies (>2 mm) were 4% and 34% (p=0.004). Sclerosis developed around the implant in all feet. Titanium grommets appear to protect the implant and improve clinical outcomes.