A cautionary case: osteoporotic femur fracture after robotic-assisted total knee arthroplasty

Osteoporosis is a disease of low bone mass which leads to an increased risk of fracture. The prevalence of osteoporosis is greatest amongst postmenopausal women who also form a large portion of patients with osteoarthritis presenting for total knee arthroplasty. We present a case of a 77-year-old female with knee osteoarthritis and osteoporosis on denosumab who underwent robotic-assisted total knee arthroplasty. Postoperatively, she suffered an atraumatic midshaft femur fracture at the pin site associated with the use of intraoperative robotic technology. This is a unique complication related to the use of robotics which requires additional skeletal fixation versus standard arthroplasty surgical technique. We recommend caution and further study regarding the use of robotics in total knee arthroplasty in the setting of osteoporosis and denosumab use.