Development and clinical application of meniscal unicompartmental arthroplasty.

About one-third of osteoarthritic patients requiring knee replacement have focal lesions limited mainly to the medial compartment and can achieve excellent postoperative function after medial unicompartmental replacement. However, late failures of many unicompartmental prostheses require revision at a rate about twice that of total knee replacement. The use of a fully conforming mobile-bearing meniscal unicompartmental prosthesis in the hands of experienced surgeons can reduce revision rates to levels equivalent to the best results achieved with total knee replacement. The paper argues the case for such a prosthesis and demonstrates that the usual modes of failure of unicompartmental arthroplasty, most of them biomechanical, can thereby be avoided.