A rare bilateral variant of the levator claviculae: a case report

The levator claviculae is a rare anatomical variant located in the posterior cervical triangle, typically unilateral and left-sided, with an estimated prevalence of 1-2% of the population. We report a bilateral and asymmetric levator claviculae identified during a cadaveric dissection by first-year medical students. Recognizing this variation is of clinical interest and holds educational value for anatomical training.

The muscle was identified on both sides, each with two heads, with a more prominently developed appearance on the right. The short head originated from the transverse process of the third cervical vertebrae, while the long head originated from the transverse process of the second cervical vertebrae. The muscle on the right side inserted onto the posterolateral border of the clavicle, while on the left, it inserted into the middle of the clavicle. Bilateral innervation originated from the second, third, and fourth cervical spinal nerve rami. Blood supply to the right side originated from the transverse cervical artery, while the dorsal scapular artery supplied the left side.

This report highlights the embryological basis and clinical significance of this rare anatomical variant. Clinically, its misinterpretation could affect radiological assessment, medical diagnosis, surgical procedures, and patient outcomes.

Collectively, understanding rare anatomical variants holds clinical and educational value, shedding light on cadaveric dissection as a valuable tool not only in medical education but also in improving surgical outcomes and clinical assessment.