Upper limb

Articular cartilage of metacarpals and phalanges of hand (MCP, PIP, DIP)

Cartilagines articulares metacarpalium et phalangium manus

Origin

Hyaline cartilage on metacarpal heads, trochlear surfaces of proximal, middle, and distal phalanges

Insertion

Opposing articular surfaces of MCP, PIP, and DIP/IP digital joints

Function

Enables frictionless flexion and precise dexterity during power grip and fine pinch activities

Innervation

Avascular and aneural

Movement & chain

Gliding-rolling kinematics during digital flexion and extension

Palpation

Not palpated directly

Clinical

Heberden's nodes (DIP osteoarthritis) and Bouchard's nodes (PIP osteoarthritis); rheumatoid arthritis with ulnar drift.

Segmental innervation

C7–T1

In clinical practice

Hand therapy, paraffin wax baths, active-assisted range of motion, and ring splinting

Region in the model

Upper limb