There was a dislocation of the greater multiangular 1st metacarpal joint and a fracture of the proximal thumb phalanx, with consequent adduction contracture of the right thumb (Fig. 9 A).

(a) Oblique radiograph of the left thumb demonstrating dorsal subluxation of the first metacarpal bone at the basal joint ... the proximal phalanges of the thumb and index finger, and the ...