Abstract: An endoprosthetic metatarso-phalangeal replacement joint permitting dorsi and plantar flexion with minimal medial and lateral motion and true ginglymus motion. The device includes a male joint member that is surgically implanted in the proximal phalangeal base, the male member including a metallic cylinder connected to a tissue-inert plastic intramedullary stem, the cylinder having inert material embedded therein integrally coupled to said stem forming a drum-shaped head. The embedded inert material walls at each end of the head are recessed. The female joint member includes a molded, tissue-inert plastic intramedullary stem integrally formed with a socket having a partially cylindrical wall of a predetermined arcuate length relative to the axis longitudinally of the intramedullary stems that receives the drum-shaped head of the male joint member.