Five Questions to Identify Patients With Osteoarthritis of the Knee

Abstract Background To treat the increasing number of patients with Osteoarthritis (OA) of the knee, high volume institutions rely on central referral services as first contact point. Depending on the grading of arthritis patients will be referred to a non-operative or operative care provider. The current study reports on a simple five step questionnaire to identify patients with OA (KL grade ≥ 2) of the knee to improve efficiency of referrals. Methods We included 998 patients that contacted the Physician Referral Service at the author’s institution complaining of knee pain and divided them into two groups. The study group included patients with an appointment and consisted of 646 patients (345 women (53.4%) and 301 men (46.6%)). X-Rays of the knee were graded according to the Kellgren/ Lawrence (KL) classification system. The control group of patients that did not make an appointment consisted of 352 patients (187 women (53.1%) and 165 men (46.9%)). These patients were contacted to evaluate if they had been diagnosed with OA of the knee since their initial call, to assure that the study group was not exposed to a selection bias. Results Logistic regression revealed five questions as significant predictors for OA of the knee (KL grade ≥ 2). When combining both groups, an 86.9% sensitivity, a 73.3% specificity and an 84.3% overall accuracy were reached, when patients answered three or more questions positively. Conclusion The current study revealed a simple five step questionnaire to identify patients with OA of the knee. Implementation of the questionnaire has the potential to improve the accuracy of referral processes and streamline organization prior to the first medical appointment.