The metacarpals (MCP’s) form the bases of our finger and our knuckles are the ends of these bones. These injuries are less common than injuries to the PIP and DIP joints (Dines et al., 2012).
As in all finger joints, the main movements in the MCP is extension, flexion, adduction, abduction and circumduction.
Repetitive gripping and grasping can cause pressure over the top of the knuckles; generally Sprains and dislocations of the metacarpophalangeal (MCP) joint of the finger are relatively rare due to the protected position of this joint in the hand.
Buddy taping or strapping is a quite common way to splint the injury until the pain fades (Dines et al., 2012).
Dines J.M. et al., 2012, Sports Medicine in Baseball, Lippincott Williams & Wilkins, Philadelphia, PA, p:300