The Levator Claviculae Muscle Presenting as a Neck Mass.

The levator claviculae muscle is an uncommonly encountered muscle variant, occurring in 1% to 2% of the human population. Most accounts of the levator claviculae muscle have been reported in association with routine cadaveric examination and as an incidental finding by computed tomography (CT) and magnetic resonance (MR) imaging. We report a case of this variant muscle presenting as a soft-tissue mass within the neck of a young male. Furthermore, we discuss the embryologic origin, imaging features and clinical implication.