Geometric knee replacement arthroplasty: Indications for operation and preliminary experience

Geometric total knee replacement arthroplasty is not recommended for general use until a longer follow up is available. The early results of the operation are encouraging enough, however, to warrant further clinical trial. Failures of previous surgery have been salvaged successfully, and severe conditions of the knee joint have been treated that previously could bave been managed only by arthrodesis. At the present time the geometric total knee replacement is indicated in patients who have had previous osteotomies, tibial plateau or femoral mold arthroplasties, or synovectomies that have failed to provide pain relief and stability. The contraindications for tibia osteotomy are reasonable indications for geometric total knee replacement: a flexion contracture of 20° or more, gross instability, and disease involving both compartments of the knee joint. In rheumatoid arthritis, when the disease is past the synovial stage and joint damage is present with instability and a flexion contracture of more than 20°, a geometric total knee replacement may be a more appropriate operation than tibial plateau replacement, femoral mold arthroplasty, or hinged total knee replacement. Obviously a longer follow up is needed to verify this impression.