All joints
Joint guide
MCP joints (knuckles)
The big knuckles where each finger meets the palm bones. They spread, curl, and help form the roof of the hand for grip and cupping.
Diagram
Schematic for orientation — not a substitute for imaging or an in-person exam.
Digit-specific guides
Pages for each finger ray and hinge that roll up to this joint family.
Related anatomy topics
Sources & further reading
We cite major society patient education, NIH institute pages, and MedlinePlus for naming and general joint context. Links open in a new tab; access dates help you judge currency when guidelines update.
- Arthritis of the hand — OrthoInfo — American Academy of Orthopaedic Surgeons(accessed 2026-04-24)
- Hand and wrist anatomy — American Society for Surgery of the Hand(accessed 2026-04-24)
- Hand problems and arthritis — National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIH)(accessed 2026-04-24)