Anatomy of the Platysma and Lip Depressor Muscles

Abstract

The popularity of submental suctioning, platysmaplasty neck lifts, and now Botulinum A exotoxin injections into the neck has increased dramatically. A detailed working knowledge of clinical platysma and lip depressor muscle anatomy is of paramount importance to successfully anesthetize and block the treated areas, to avoid injury to important vessels, nerves, and deeper cervical structures, and to optimally treat the problem areas. A simple, user-friendly knowledge can be obtained by remembering simple mnemonics relating to (1) specific target areas, (2) anatomic relationships, and (3) topographic clinical landmarks.

Liposuction of Neck and Jowls: Five-Incision Method Combining Machine-Assisted and Syringe Aspiration

“…The incidence of fat overresection from the jowls and of injury to the marginal mandibular nerve is relatively low. 3 A single patient in this series experienced temporary paresis of the marginal mandibular nerve. In this area it is preferable to aspirate from the deeper levels of the jowl fat pad.…”

Asymmetrical Smiles Corrected by Botulinum Toxin Serotype A

“…It is essential that a physician possess a comprehensive understanding of the functional anatomy of the mimetic muscles of the face when treating patients with BTX 4,5 . When evaluating the patients in this pilot study, it became apparent that the asymmetries of their lower lips were created by the enhanced downward pull of one of the paired DLIs 6 . The idiosyncratic, unilateral, hyperkinetic DLI of the lower lip caused an ipsilateral retraction of the lip margin lower than its contralateral side, which resulted in lip asymmetry during a smile or while laughing.…”

Anatomical Dissection and Modified Sihler Stain of the Lower Branches of the Facial Nerve

“…Localized contraction may cause platysmal bands of the aging neck, and platysmal hyperkinesis resulting from faulty nerve regeneration can cause more severe aesthetic and functional deformities of the neck. 3,[12][13][14][15] Despite these clinically significant problems, the cervical branch has received little attention in the surgical literature. The purpose of this study was to provide a detailed description of the anatomy and function of the cervical branch of the facial nerve to guide surgeons operating in the face and neck in planning incisions, injecting botulinum toxin type A, performing dissections in the submandibular region, and devising therapies for functional or aesthetic deformities of the neck.…”

“…3,4,14 Alternatively, this could result from coinnervation of the lip depressors by both the marginal mandibular and cervical branches of the facial nerve. 15,16 Studies of the anatomy and function of the cervical branch are few and have failed to clarify this controversy. Anatomical studies using embalmed cadaver specimens are limited in their ability to trace peripheral nerves to their fine terminal branches and end targets.…”