The Professor tells me there is a muscular slip, a dependence of the platysma myoides, which is called the risorius Santorini.
If so, perhaps the platysma could be observed in such cases.
On cutting through the skin and platysma some small veins may be met with: they should be clamped with forceps and divided.
In only four of the cases was the platysma visibly contracted; and it did not begin to contract until the patients began to cry.
Several persons have pointed out my error about the platysma.
It must include skin, fascia, and platysma, and the flap must be thrown upwards.
In all cases the contraction of the platysma causes the wound to gape widely, and its edges tend to be turned in.
I find, to my surprise, whenever I act thus my platysma contracts.
He then voluntarily shuddered, as he had done on former occasions, but the platysma was not then affected.
The platysma myoides, which is well developed on the neck, belongs to this system, but cannot be voluntarily brought into action.
platysma pla·tys·ma (plə-tĭz'mə)
n. pl. pla·tys·mas or pla·tys·ma·ta (-mə-tə)
A platelike muscle in the neck extending to the lower face with origin from the subcutaneous layer and fascia covering the greater pectoral and deltoid muscles at the level of the first or second rib, with insertion to the mandible, the risorius muscle and platysma of the opposite side, with nerve supply from a branch of the facial nerve, and whose action depresses the lower lip and wrinkles the skin of the neck and the upper chest.