Each and every metacarpal includes a foundation, shaft along with a head. The medial and lateral surfaces with the metacarpals are concave, allowing for attachment from the interossei muscles. Boutonniere Deformity: The MCP (metacarpophalangeal) joints as well as DIP (distal interphalangeal) joints are impacted.  The first harm is always to flexion https://www.theorthopaedicandpainpractice.com/what-are-the-different-bones-found-in-my-hand/