A midterm follow-up study of bioreconstructive polylactide scaffold implants in metacarpophalangeal joint arthroplasty in rheumatoid arthritis patients.

This paper presents the results of a prospective study of 80 metacarpophalangeal joint arthroplasties, in which biodegradable polylactide 96/4 copolymer scaffolds were used. Twenty-three rheumatoid arthritis patients were assessed at an average of 59 months after operation, which exceeds the resorption time of P(L/D)LA 96/4 according to animal experiments. Palmar subluxation exceeded half of the bone thickness in 39 joints before operation and in nine at the last follow-up. Ulnar deviation decreased from 25 degrees to 5 degrees , extension deficit from 32 degrees to 15 degrees and active flexion from 76 degrees to 63 degrees . The results are comparable with published data on silicone implant arthroplasties. Implant resorption did not induce any significant osteolysis in the medium term and the restoration of the structure and function of the hand was maintained after implant resorption, probably as the guided fibrous tissues had replaced the dissolved implant.