A minimum 15 year follow-up study
Squire MW, Callaghan JJ, Goetz DD, Sullivan PM, Johnston RC Department of Orthopaedic Surgery, University of Iowa College of Medicine, Iowa City 52242, USA.

Abstract — One hundred forty cemented unicompartmental knee replacements [partial knee resurfacing] were inserted in 103 patients between 1975 and 1982. Fifty-two patients were women and 51 were men. One hundred twenty-five were medial compartment knee replacements and 15 were lateral knee replacements. At minimum 15 year follow-up 34 patients with 48 knee replacements were living; only four patients with four knee replacements were lost to follow-up. Average preoperative and final follow-up Hospital for Special Surgery knee scores were 57 and 82 points, respectively for the knees of living patients. Average preoperative and final follow-up Knee Society clinical and Knee Society functional scores were 31 and 42, and 85 and 71 points, respectively. For all knees, 10.2% (14 knees) were revised [4.4% (six knees) for tibial loosening, 5.1% (seven knees) for disease progression, and .7% (one knee) for pain]. For patients living 15 years, 12.5% (six knees) were revised [2.1% (one knee) for tibial loosening, and 10.4% (five knees) for disease progression]. Revision for failure of fixation of these unicompartmental replacements was comparable with that reported for fixed bearing total knee replacement. Disease progression (46%; 62 of 136 knees) and tibial subsidence with wear (10.4%; 15 of 136 knees, five of which required revision) were the major long term problems in this group of patients.
 
Clinical Orthopaedics, (367):61-72 , October 1999