His own research is focused on biomechanics and hip and knee arthroplasty surgery. He has contributed to the construction of one of Sweden’s largest hip and knee arthroplasty center in Sweden located in Lindesberg where much of the research is performed. Per Wretenberg is head of a project that aims for better precision during arthroplasty surgery (navigation) and also a project that focuses on evaluation of implant function in the body. The research is done in close collaboration with the industry.