Rodilla is a low-cost adjustable knee prosthesis. When an amputee has had a transfemoral amputation, they need a prosthesis that replicates the thigh, knee, shin/calf and foot. Rodilla fits into any prosthesis that uses a standard pyramid connector, a common industry part. The design is based on a tension spring mechanism and a single bar linkage system. This allows the amputee to be able to easily walk on variable terrain and adjust the tension in the knee as needed.