Assertion: metacarpal's base | /r/CapableOf | form trapeziometacarpal joint
Facets:
Source sentences:
text: On its head, it articulates with the proximal phalanx of the thumb  to form the first metacarpophalangeal joint, while the base of the first metacarpal articulates with the carpal bone trapezium to form the carpometacarpal joint of the thumb or the trapeziometacarpal joint (TMJ) .