 Invitation letters and participant information sheets will be sent out to suitable patients prior to their preoperative consultation. They will be approached at their consultation visit to seek consent to take part in the study. At this time they will be given the opportunity to ask questions about the study. Following written consent, the patient will be randomised using sequentially numbered opaque sealed envelopes. A nominated person, independent of the approach and consent of the patient, will sign and open the envelope and inform the hospital research team of the randomisation. The patient and the university research team will be blinded to randomisation. For each patient arrangements will be made for their preoperative movement analysis testing session. Subsequently, they will have their surgery and rehabilitation prior to discharge according to standard hospital practice. Participants will then return to the hospital for standard follow up appointments at six weeks and one year. At the same time arrangements will be made for them to attend their follow up movement analysis sessions. Clinical data recorded at preoperative assessment and postoperative follow up appointments, such as range of movement, Oxford Knee Score, patient satisfaction, EQ5D and radiographic measurements will be collected for study patients to compare to the functional outcomes measured during the movement analysis sessions. 