WHAT PROPORTION OF KNEE SURGERY PRACTICE IS OSTEOARTHRITIS AND ARE WE TREATING IT CORRECTLY

Introduction Total knee arthroplasty (TKA) accounts for 84% of all knee replacement surgery in the UK (NJR 2009) despite published epidemiological data showing that single compartment disease is most prevalent. We investigated this incompatibility further by describing the compartmental pattern and stage of cartilage loss of all patients with osteoarthritis (OA) presenting to a specialist knee clinic over one year. Methods All new primary referrals in a calendar year by local General Practitioners to knee clinic at a United Kingdom Hospital were assessed. Tertiary referrals and second opinions were excluded. The final diagnosis after all imaging was recorded and tabulated. The standing AP, lateral and skyline radiographs of all cases of arthritis were scored to assess the pattern of disease. Results 1029 new patients attended clinic. OA accounts for 52% of all attendances, meniscal pathology 17%, other diagnoses less than 10% each (Fig.1). 533 patients presented with osteoarthritis, mean age was 65 years (SD 11.6). Only 23% showed a tricompartmental pattern and another 3% medial and lateral compartment. 62% were medial and 8% lateral, approximately half with patellofemoral involvement, and 4% pure patellofemoral (Fig.2). Discussion Osteoarthritis still presents the majority workload for the modern knee surgeon. Tricompartmental disease accounted for only 23% of presentations although joint registry data shows that the majority of patients undergo TKA Interestingly, the majority of these patients did not have full-thickness cartilage loss. Best treatment of end stage, ‘bone-on-bone’ OA is well known to be arthroplasty but the treatment of choice for the commonest presentation, the failing joint with early cartilage loss, is presently unknown.