Fibromatosis Colli

  • Etiology: birth trauma -> sternocleidomastoid muscle hemorrhage / pressure necrosis -> fibrosis -> contracture of sternocleidomastoid muscle
  • Imaging: right > left, spindle shaped enlargement of sternocleidomastoid muscle lower half
  • Clinical: conservative range of motion therapy

Cases of Fibromatosis Colli

CT and US of fibromatosis coli / torticollis tumor
Axial CT with contrast of the chest (above) shows asymmetry of the sternocleidomastoid muscles, right larger than left. Transverse US of the chest (middle) at the same level of the CT better shows the enlarged right sternocleidomastoid muscle. Sagittal US of the sternocleidomastoid muscles (bottom) shows the normal smooth contour of the left sternocleidomastoid muscle and the spindle shaped appearance of the right sternocleidomastoid muscle.
US of fibromatosis coli
Transverse US of the neck shows a normal sized hyopechoic left sternocleidomastoid muscle lying above the jugular vein and carotid artery. The right sternocleidomastoid muscle is more heterogenous in echotexture and is 3-4 times larger in size than the left.
US of fibromatosis coli
Transverse US of the neck shows a normal sized hypoechoic right sternocleidomastoid muscle lying above the jugular vein and carotid artery. The left sternocleidomastoid muscle has a heterogenous echotexture and is 5-6 times larger in size than the right.