FIRST CMC - PART POSITION & STRUCTURES SHOWN

First CMC – AP/AP Axial Projection

Internally rotate hand with fingers extended until posterior surface of thumb is in contact with IR. Immobilize other fingers with tape to isolate thumb if necessary. Align thumb with long axis of the IR. Center first MCP joint to CR and to center of IR. Immobilize if necessary.

First CMC – AP Projection (Burman Method)

Place the IR under the wrist, and center the first CMC joint to the center of the IR. Hyperextend the hand, and have the patient hold the position with the opposite hand or with a bandage looped around the digits. Rotate the hand internally and abduct the thumb so that it is flat on the IR.

First CMC – PA Stress Projection (Folio Method)

Position both hands side by side to center of IR, rotated laterally into oblique position, resulting in PA projection of both thumbs. Place supports as needed under both wrist and proximal thumb regions to prevent motion. Ensure that hands are rotated enough to place thumbs parallel to IR (cassette) for PA projection of both thumbs. Place round spacer (e.g., roll of medical tape) between proximal thumb regions

First CMC – AP/AP Axial Projection

This projection shows the first CMC joint free of superimposition of the soft tissues of the hand.

First CMC – AP Projection (Burman Method)

This image shows a magnified concavoconvex outline of the first CMC joint.

First CMC – PA Stress Projection (Folio Method)

Entire thumbs from first metacarpals to distal phalanges. Demonstrates metacarpophalangeal angles and joint spaces at MCP joints.