FIRST CARPOMETACARPAL (CMC) JOINT

Question 1

PP: Shoulder, elbow & wrist on same plane (prevent carpal bones elevation & closing 1st CMC joint); arm internally rotated; hand hyperextended; dorsal aspect of thumb against IR
RP: 1st CMC joint
CR: ┴; 10-15o proximally (Lewis Method); 15o proximally (Rafert-Long Method)
SS: 1st CMC joint
ER: To demonstrate arthritic changes; fractures; 1st CMC joint displacement; Bennett’s fracture
Angulation Rationale: To project soft tissue of the hand away from 1st CMC joint; help open joint space

Answer 1

ROBERT METHOD
AP PROJECTION

Question 2

PP: Hand hyperextended; opposite hand hold the hyperextended hand or bandage loop around digits; hand rotated internally; thumb abducted
RP: 1st CMC joint
CR: 45otoward the elbow
SS: Magnified 1st CMC joint
ER: To provide a clearer image of 1st CMC than standard AP

Answer 2

BURMAN METHOD
AP PROJECTION

Question 3

PP: Hands rested on medial aspect; distal portion of both thumbs wrap around by a rubber band; thumb in PA plane
RP: b/n level of MCP joints of both hands
CR: ┴
SS: 1st CMC joint; bilateral MCP joints & MCP angles
ER: Useful for diagnosis of ulnar collateral ligament (UCL) rupture\

Answer 3

FOLIO METHOD/SKIER’S THUMB
PA PROJECTION