The goal of reducing the length of a patient's hospital stay after orthopaedic surgery has recently gained much interest from surgeons and hospital administrators. The influence of hospital stay reduction on qualitative outcome is not always documented. The purpose of this study was to investigate this relationship in more detail. We report our experience with patients undergoing total knee arthroplasty. In 2000, an in-hospital clinical pathway for patients undergoing total knee arthroplasty was instituted at the University Hospitals Pellenberg, Belgium. We evaluated this pathway in 103 patients by using a pre-experimental, interrupted, time-series design. This pathway significantly decreased length of stay by 33% without negatively affecting functional outcomes during hospitalisation. In further research also the long-term effects have to be studied.