A system for attaching a middle phalanx and a proximal phalanx together may include a middle component and a proximal component. The middle component may have a middle component bone fastener implantable into a first bore formed in the middle phalanx, and a middle component attachment end with a first engagement feature with a first shape. The proximal component may have a proximal bone fastener implantable into a second bore formed in the proximal phalanx, and a proximal component attachment end with a second engagement feature with a second shape. The first engagement feature may be movable into engagement with the second engagement feature along an engagement direction that is generally perpendicular to the middle phalanx and/or the proximal phalanx. The second shape may be complementary to the first shape such that the first engagement feature interlocks with the second engagement feature.