The platysma muscle has been widely studied in its course through the cervical region in an attempt to develop more effective surgical approaches for rejuvenation. As a person ages, the platysma muscle becomes thinner, less defined, and ptotic, which results in the clinical appearance of a sagging neck that prompts patients to undergo neck-lift procedures. However, little is known about the course of the platysma in the mid and lower face and the implications on facial aging.
Bae et al (Plast Reconstr Surg. 2016;138:365-371) performed a cadaveric dissection of the facial portion of the platysma muscle to delineate the morphology and extension of the muscle in the mid and lower face. Thirty-four adult hemifaces were dissected. The demographics were broken down by age (mean, 71.4 years; range, 41–93 years), gender (29 men; 5 women), and ethnicity (14 Korean; 20 Thai). The extension of the platysma was documented according to a grid the authors created. The grid was divided along 3 horizontal lines (H1–H3) and 3 vertical lines (V1–V3). The intersection of these lines created a grid that was comprised of 3×3 squares and was labeled superior (S1–S3), middle (M1–M3), and inferior (I1–I3). H1 was a line drawn horizontally from the tragus to the lateral orbit, H2 was a line from the earlobe to the nasal ala, and H3 was a line from the angle of the mandible to the corner of the mouth.
The extension pattern of the facial portion of the platysma muscle was classified into patterns: A (n=3; S1–S2, M1–M3, and I1-I3 were covered by the muscle), B-1 (n=20; M1–M3, I1–I3), B-2 (n=9; M1–M2, I1–I3), and C (n=2; I1-I3).
The platysma muscle is divided into anterior and posterior portions. The anterior platysma ascends superiorly and medially in the face to interdigitate with the depressor anguli oris and the depressor labii inferioris muscles. The morphology pattern of the posterior platysma varied and was classified into 1 of 3 patterns: straight (n=13), straight-curved (n=18), and curved (n=3). The straight pattern showed platysma fibers that travel parallel to the mandibular malar line and head toward the zygomaticus major or the orbicularis oculi muscles. The straight-curved type has fibers that travel straight from the neck to the face but then curve, heading toward the risorius, zygomaticus major, or orbicularis oculi muscle depending on the extent of the platysma muscle in the area. The curved type has fibers that run parallel to the zygomaticus arch and interdigitate with the orbicularis oculi muscle and either the risorius or zygomaticus major muscle.
What’s the issue?
For many years, the cervical platysma muscle was studied and surgical approaches were modified to enhance results. The authors of this study have taken the study of the platysma muscle further to delineate its course through the face. Knowledge of the various pathways of the muscle can help us determine the most natural direction to resuspend ptotic facial tissue during surgery and minimally invasive procedures such as thread-lifting. The most salient points include: (1) the lower one-third of the masseter muscle is covered by the platysma, and (2) straight-curved was the most common morphology type, suggesting that the vector for repositioning the platysma muscle is vertical.
Although Bae et al do not discuss the use of botulinum toxin (BTX) in the treatment of the platysma, the results of this study further support the importance of BTX to the lower face. We can look back at more than 14 years of cosmetic use of BTX for the glabella and see the reduced number of brow-lift surgeries nationwide. Although the preventative effects of BTX on brow depression still need to be scientifically proven, it may behoove us to think preventatively on the use of BTX in the platysma to minimize ptosis of the lower face and neck. The results of this anatomic study support the importance of tailoring the approach to the dynamic lines caused by the platysma muscle in each patient to address jowls and neck bands. Have you been offering lower face BTX treatments to patients in an effort to reduce lower face aging?