Results of unicompartmental knee replacement

To present the results of medial unicompartmental knee replacement of patients admitted at a university hospital in Jeddah, Saudi Arabia.

Of the 99 patients who received medial hemiarthroplasty of the knee since 1989 to 2005, 90 patients (132 operations) with a minimum follow up of one year were evaluated at King Abdul-Aziz University Hospital in Jeddah. Only one patient (2 prostheses) was lost for follow up. Eleven patients (11 prostheses) died after an average time of 108.5 months (36-180 months). Scores were registered according to the Knee Society Clinical Rating System.

There was a significant improvement in all functional scores postoperatively throughout the follow up period. One patient developed symptomatic deep vein thrombosis in the calf of the operated leg. There were no other perioperative complications. Twelve patients (14 prostheses) underwent conversion to total knee replacement due to either aseptic loosening of the tibial component (1 prosthesis) or polyethylene wear (3 prostheses) or progression of degenerative disease in the lateral compartment (7 prostheses). Two of these 12 patients (3 prostheses) were operated on at another hospital and no information on the reason for operation is available.

Unicompartmental knee replacement can be used successfully for the treatment of medial gonarthrosis. Given the proper patient's selection and technical expertise, hemiarthroplasty can give results comparable to or even better than high tibial osteotomy or total knee replacement.