A cross-sectional study of 100 surgeons and 370 patients awaiting primary total hip or knee replacement was carried out. Oxford hip or knee score questionnaires were sent to the surgeons and patients. They were asked to predict the level of symptoms expected 6 months following surgery. The Oxford scores derive a value of 12-60, with a greater score indicating worsening symptoms. The mean pre-operative score was 45.12 for the hip patients and 42.96 for the knee patients, and the patients expected this to drop to 23.70 and 25.66, respectively, 6 months' postoperatively. This was a significant difference for both groups. The surgeons expected the patients to have a mean postoperative score of 20.91 for the hip group and 22.19 for the knee group. The surgeons' scores were significantly lower than those from the patients. There was a significant difference between the patients' and surgeons' expectations of the results of total knee and hip replacement surgery. The surgeons expected better results than the patients. We believe that this is the first study that directly compares surgeon and patient expectations of lower limb arthroplasty.