General discussion 129 No radiological assessment was used to assess the alignment of the fractures during aftercare treatment and therefore no evidence on the amount of discordance between patient-reported outcomes and radiological alignment is available currently. The answer to this question might indicate whether more frequent/longer radiological follow-up is required in the current PWB aftercare protocols. A long-term follow-up period might be needed to provide more evidence into functional outcome and complications (effectiveness) of PWB in comparison to RWB. In summary, future studies are needed on the long-term (cost)-effectiveness, radiological assessment, and long-term patient-reported outcomes of the PWB strategy in comparison to RWB. Implementation of PWB-based treatment regimen in the rehabilitation community across the world is a challenge that needs to be addressed. This thesis showed that permissive weight bearing is safe, effective and cost-effective to be implemented in trauma patients with peri and or intra-articular fractures of the lower extremities. The patients should not longer be restricted in weight bearing. More insight in permissive weight bearing and more effort is needed to optimize the implementation of permissive weight bearing across the world. Implementation activities will be tailored to barriers and facilitators to change. We identified as most important barriers the necessary change in mindset in trauma- and orthopaedic surgeons who need to de-implement the current strategy of prolonged non-weight bearing and the lack of knowledge in physiotherapists. Implementation activities will focus on increasing awareness in trauma and orthopaedic surgeons. In trauma and orthopaedic surgery the international guidelines of the AO foundation are an important tool in implementing new practices. These guidelines are widely used in Europe and are translated in Dutch language for use at a national level. Adaptation of the AO fracture guideline is important for successful implementation of permissive weight bearing. Furthermore, educational activities have to be deployed to improve knowledge and skills of physiotherapists. These activities will be multimodal and comprise educational materials and large and small scale educational meetings. Finally, an application for mobile devices is needed to guide the permissive weight bearing at patient level.