Jordy van Sambeeck

Chapter 9 156 measurements is a thorough knowledge on normal and abnormal patellofemoral anatomy, physiology, pathophysiology and surgical treatment. Therefore, we advise that only surgeons educated or experienced in patellofemoral surgery should perform these type of operations. With the right education and experience, intra operative measurement of distance (often in terms of millimeters) in the right plane and direction combined with intra-operative testing for stability, is still the most accurate and reliable verification method to assess if the amount of correction that is achieved is correct so far. The surgeon has to take the lack of dynamic stabilization intra-operatively into account. However, in the future, 3D navigated and controlled surgical instrumentation and patient specific instrumentation can probably improve intra-operative measurement of correction which has been planned using software including dynamic stabilization. Future perspectives on outcome measurement Toimproveourunderstandingofperceiveddisabilitybypatientswithpatellofemoral instability, a multicenter study in which patients are urged to fill out these patellar instability specific PROMs at first consultation and then consequently at follow- up, independent of nonoperative or operative treatment is expedient. This will increase our understanding of the natural course of impact on daily living and quality of life of patellofemoral instability, something we still do not completely understand. A majority of patients are seen first by an orthopedic surgeon at adolescence. The expected impact on their future quality of life is hard to predict and decision making is partly based on personal experience of the surgeon. However, those patients are at an age that they have to make critical choices for the rest of their life and are looking for a more specific answer on the question of the natural course of impact of these complaints. A large epidemiological study in cooperation with general physicians (GP’s) could possibly increase our knowledge on the natural course of impact on quality of life of patellofemoral instability. The future perspectives outlined above illustrate that there are numerous opportunities to optimize the multidimensional treatment of patients with patellofemoral instability. It also illustrates that there is still a research and knowledge gap. Some future research topics that could be explored include: − Assessment and validation of normal values for 4D CT-scanning in normal knees and in knees of patients with patellofemoral instability and trochlear dysplasia. − Which (maybe a new) measurement for lateralization is the optimal for use on 4D CT-scanning? − Validation and assessment of accuracy and clinical relevance of computer simulation based on 4D CT-scanning.