Abstract
Osteoarthritis of the knee is commonly a disease which afflicts more than one compartment of the knee so medial compartment arthritis is almost always associated with patellofemoral and or lateral compartment disease to a lesser extent. In a review of 250 consecutive osteoarthritic knees strictly unicompartmental involvement occurred in less than 15% of affected knees. To segmentally replace one compartment when more than one is involved may lead to a suboptimal result from the compartmental replacement as well as lead to pain and failure with mid- to long-term follow up. The long term results with tricompartmental replacement continue to show success rates in the order of 90–95% at 15–20 year follow-up with multiple designs and fixation types. Additionally failure to replace the patella, although popular in Europe, has led to increased anterior knee pain in studies in North America. The disadvantage of tricompartmental knee replacement is the extent of surgical trauma compared to compartmental replacement although newer less invasive approaches may lead to similar recovery to compartmental replacement.
