Abstract
Introduction: Unicompartmental knee Arthroplasty (UKA) is a commonly used and accepted treatment for Osteoarthritis (OA) in the medial compartment. How-ever, despite some good results1 there is still a reluctance to use this procedure in the lateral compartment for the same indications, as the procedure is considered technically difficult, and not as successful2. This study reports the clinical outcome of lateral UKAs in comparison with medial UKAs, TKAs and a normal population group using a knee score designed to highlight the shortcomings of TKA3.
Methods: 20 consecutive patients over 2 years following lateral UKA were functionally assessed. They were compared with 3 groups of 20 age and sex matched patients: those who had undergone medial UKA or TKA in the same time period, or normal controls from an upper limb clinic. Clinical function was assessed at least 2 years postoperatively, using the ‘total knee questionaire’3. This consists of 55 scaled multiple choice questions. The score is derived from the product of three scales: the importance of a specific activity, the frequency with which it is undertaken, and the ease with a patient can perform it.
Results: 90% of the patients reported that they were either satisfied or very satisfied with their lateral UKA, with 95% of the patients in the medial UKA group and 75% in the TKA group reaching this level of satisfaction. The average Composite Score for the lateral UKA group was significantly better compared with the TKA group (p < 0, 05). (Kneeling – (5,72/4,45), Gardening – (7,32/5,18), Pivoting – (7,83/6,78) and Walking with heavy bags (8,2/5,97)). The Total Composite Score was significantly better (p< 0, 05) in Patients after lateral UKA (7,14) compared to patients who underwent TKA (5,99). No statistically significant differences in the Total Composite Score was found between both the lateral & medial UKA patients taken as a single group compared with the control group.
Conclusion: Lateral Unicompartmental Knee Arthroplasty achieves superior knee function in comparison to Total Knee Arthroplasty, so is worth considering as an option in for early OA of the lateral compartment.
Correspondence should be addressed to: EFORT Central Office, Technoparkstrasse 1, CH – 8005 Zürich, Switzerland. Email: office@efort.org
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