Which of the following finger has two dorsal interossei (AIIMS May 2019)
(A) Little (B) Ring (C) Middle (D) Index
(C) Dorsal interossei: Dorsal interossei are major abductors of index, middle & ring fingers. Most dorsally situated of all intrinsic muscles. Palpated through skin on dorsal aspect of hand. Tendons of dorsal interossei pass dorsal to deep transverse metacarpal ligament. - 1st dorsal interosseous muscle - largest & inses into lateral side of index finger. - 2nd& 3rd interosseous muscle - inse into lateral & medial sides respectively of middle finger. - 4th dorsal interosseous muscle - inses into medial side of ring finger. Thumb & little finger do not have dorsal interossei as they have their own abductors in thenar & hypothenar muscle groups respectively. Dorsal interossei + palmar interossei + lumbricals flex-metacarpophalangeal joint & extend inter - phalangeal joint.