Introduction: Oxford Unicompartmental knee arthroplasty (UKA) is now performed using a minimally invasive surgical (MIS) technique. Although early results are encouraging, the studies assessing outcome could be criticised for the restricted number of patients and centres involved. A multi-centre follow-up of patients is required to confirm the preliminary findings.

Aim: To examine early clinical outcome in patients with minimally invasive Oxford medial UKA using a multi-centre, multi-surgeon design.

Materials and Methods: This prospective study was carried out in three centres with involvement of six surgeons. All patients undergoing cemented Oxford UKA for medial OA using MIS were included. 231 consecutive UKAs with a minimum follow up of 2 years (mean: 2.84) were assessed using objective and functional Knee Society Score (KSS).

Results: There were 108 females and 102 males (21-bilateral) with average age of 66.8 years (42 – 86). No significant difference was noted between various age groups or between different surgeons. Three knees were revised: one for infection, one for unexplained pain and one for bearing dislocation. Cumulative survival rate at 2 years was 98.6% with 93% patients having good or excellent KSS rating.

Conclusions: This multi-centre study has confirmed preliminary findings that Oxford UKA using a minimally invasive approach is safe and effective.