Aesth Plast Surg (2023) 47:170–180

https://doi.org/10.1007/s00266-022-02996-3

ORIGINAL ARTICLE FACIAL SURGERY

The Surgical Anatomy of the Jowl and the Mandibular Ligament

Reassessed
Lennert Minelli1,2,3,4 • Hun-Mu Yang5 • Berend van der Lei4 • Bryan Mendelson1

Received: 19 April 2022 / Accepted: 4 June 2022 / Published online: 1 September 2022
Ó The Author(s) 2022, corrected publication 2022

Abstract mandibular ligament proper exists only in the deep, sub-

Introduction A visible jowl is a reason patients consider platysma plane, formed by the combined muscular
lower facial rejuvenation surgery. The anatomical changes attachment to the mandible of the specific lower lip
that lead to formation of the jowl remain unclear. The aim depressor muscles and the platysma. The mandibular
of this study was to elucidate the anatomy of the jowl, the ligament does not have a definitive subcutaneous compo-
mandibular ligament and the labiomandibular crease, and nent. The labiomandibular crease inferior to the oral
their relationship with the marginal mandibular branch of commissure marks the posterior extent of the fixed dermal
the facial nerve. attachment of depressor anguli oris.
Materials and Methods Forty-nine cadaver heads were Conclusion Jowls develop as a consequence of aging
studied (16 embalmed, 33 fresh, mean age 75 years). Fol- changes on the functional adaptions of the mouth in
lowing preliminary dissections and macro-sectioning, a humans. To accommodate wide jaw opening with a nar-
series of standardized layered dissections were performed, rowed commissure requires hypermobility of the tissues
complemented by histology, sheet plastination and micro- overlying the mandible immediately lateral to the level of
CT. the oral commissure. This hypermobility over the
Results The jowl forms in the subcutaneous layer where it mandibular attachment of the lower lip depressor muscles
overlies the posterior part of the mandibular ligament. The occurs entirely in the subcutaneous layer to allow the
mandible to move largely independent from the skin. The
short, elastic subcutaneous connective tissue, which allows
this exceptional mobility without laxity in youth, lengthens
with aging, resulting in laxity. The development of sub-
& Lennert Minelli
Lennert.minelli@gmail.com;
cutaneous and dermal redundancy constitutes the jowl in
https://mafac.com.au this location.
Level of Evidence IV ‘‘This journal requires that authors
1
Melbourne Advanced Facial Anatomy Course (MAFAC), assign a level of evidence to each article. For a full
Australasian Society of Aesthetic Plastic Surgeons (ASAPS),
PO Box 592, Toorak, VIC 3142, Australia
description of these Evidence-Based Medicine ratings,
2
please refer to the Table of Contents or the online
Medical Engineering Research Facility (MERF), Queensland
University of Technology (QUT), Brisbane, QLD, Australia
Instructions to Authors www.springer.com/00266.’’
3
Department of Anatomy and Physiology, School of
Biomedical Sciences, The University of Melbourne,
Keywords Facial retaining ligaments
Mandible
Jowl

Melbourne, VIC, Australia Labiomandibular fold
Platysma
Aging
4
Department of Plastic Surgery, University Medical Centre
Groningen, University of Groningen, Groningen, The
Netherlands
5
Department of Anatomy, Yonsei University College of
Medicine, Seodaemun-gu, Seoul, South Korea

123
Aesth Plast Surg (2023) 47:170–180 171

Introduction

‘‘Follow? Nay, I’ll go with thee, cheek by jowl.’’ Technology for the definitive study including histology and
–A Midsommer Nights Dreame, William Shake- plastination, and the Yonsei University College of Medi-
speare, 1596 cine for the micro-CT study (Project numbers 14243,
LR2021-4306-4761, and YSAEC22-004).
The jowl is a key stigmatizing feature of the aging human
First, an exploratory study was performed on 21
face and a contributing reason why lower facial rejuvena-
cadavers, fifteen embalmed and six fresh frozen (male =
tion is considered. However, the aging changes in the
10; female = 11; mean age = 76 years) to determine how to
underlying anatomy that lead to the appearance of the jowl
most effectively study this area of complex anatomy. This
and its exact anatomical borders remain unclear. The jowl
involved layered dissections, facelift dissections and
is currently regarded as sagging of redundant facial tissue
macro-sectioning in various planes.
that is bordered anteriorly by the mandibular ligament at
the labiomandibular crease. Release of the mandibular
ligament is indicated in certain situations to obtain full
correction of the jowl during facelift surgery.
The presence of a mandibular ligament was first
described by Furnas in his 1989 classic paper, The
Retaining Ligaments of the Cheek, along with his original
description of the zygomatic ligament. Given the similarity
of their function as retaining ligaments, there has been a
natural assumption that these ligaments are anatomically
similar. Since its description, the role of the mandibular
ligament has been considered central in the development of
the jowl with aging. To date, there have been two different
explanations regarding the place of the ligament in the
pathophysiology of the jowl. Mendelson et al. described
the jowl as being in the deep (sub-platysma) plane, whereas
Reece et al. described its presence in the subcutaneous
plane (supra-platysmal).[1, 2] The mandibular ligament
itself has also been reported with considerable variation
regarding its position and extent (Fig. 1).[1, 3–8] Recent
studies have described the mandibular ligament to extend
up to 65 mm from the midline and 45 mm from the gonial
angle, which locates it much more posterior than at the
anterior border of the jowl.[8, 9] The labiomandibular
crease was demonstrated not to be formed by a ligament Fig. 1 This illustration combines the different historical descriptions
but by the direct insertion of the lower lip muscles into the of the mandibular ligament. Furnas [3] introduced the mandibular
dermis, like the nasolabial crease in the upper lip.[10, 11] ligament as ‘‘a linear series of parallel fibres along the anterior third of
the mandible which interdigitate among the muscle fibres of the
This lack of an agreed understanding has hampered con- platysma and triangularis along their line of attachment to the
fident understanding of this region during facelift surgery. mandible’’. Stuzin et al. [4] described the mandibular ligaments as
Therefore, this anatomical study was undertaken to elucidate osteocutaneous which ‘‘securely fix the parasymphysial dermis to the
the true nature of the jowl, including its bordering structures, underlying mandible’’ and illustrated it as a smaller stout ligament.
Özdemir et al. [5] reported two mandibular ligaments with mean
the labiomandibular crease and the exact location of the widths of 22-32 mm. Mendelson et al. [1] reported it in the sub-
mandibular ligament and its relationship with the marginal platysmal plane: ‘‘the mandibular ligament is located immediately in
mandibular branch of the facial nerve (MMN). front of the masseter’s anterior border’’. Huettner et al. [7] described
two ligaments in the subcutaneous plane: the mandibular osteocuta-
neous ligament (MOCL) with a mean width of 13 mm, and the
platysma mandibular ligament (PML) with a mean width of 22 mm.
Materials and Methods Kang et al. [8] described two mandibular ligaments and one mental
ligament in the sub-platysmal plane. The platysma, DLI and DAO
Ethical approval for the project was granted by the Human mandibular attachments were not mentioned, nor a subcutaneous
extension of these ligaments Reproduced with permission from
Ethics Advisory Groups of the University of Melbourne for Wolters Kluwer Health, Springer Nature, Oxford University Press and
the exploratory study, the Queensland University of Elsevier

123
172 Aesth Plast Surg (2023) 47:170–180

Based on this feasibility study, a definitive study was posterior end of the mandibular ligament. This area exhi-
conducted using standardized dissections on 14 cadavers, bits the longest length of the retinacula cutis fibres in the
one embalmed and thirteen fresh (non-frozen) (male = 8; subcutaneous plane on histology and micro-CT (see fur-
female = 6; mean age = 80 years). For the dissection, ther: ‘‘Superficial part of the Mandibular Ligament’’). The
following markings and measurements, a skin incision was sub-platysmal structures do not add to the jowl volume but
made over the clavicles through the subcutaneous fat to the to adjacent prominences: the buccal fat pad bulges superior
platysma. Then, a sweeping motion of a no. 10 blade was to the jowl, and the submandibular gland, when prominent,
used along the superficial surface of the platysma to define is inferior to the jowl
areas of increased attachment of the skin to the platysma.
The distance from the midline to such attachments was Deep Part of the Mandibular Ligament
measured. Dissection was then performed at the deep sur-
face of the platysma to determine the deep part of the In the sub-platysmal plane are the attachments of the pla-
mandibular ligament as well as the attachments of the tysma, DLI and DAO into the anterior third of the mand-
platysma, DLI and DAO to the mandible. ible. These three muscles attach to the mandible in a
Finally, objective technical investigations were used to particular and consistent manner, with the platysma most
complement the dissection findings: caudal, the DLI attachment most cephalad, and the DAO in
between these two muscles (Fig. 2). Posterior to the
(1) Histology of full-thickness macro-sections of the jowl
mandibular ligament, the platysma is loosely ‘‘connected’’
region was studied in thirteen samples of six cadavers
to the mandible by areolar connective tissue which allows
(male = 3; female = 3; mean age = 77 years).
significant mobility of the platysma over the mandible
(2) Sheet plastination of the head and neck of ten fresh
(Video 1). The muscle fibres of this posterior part of the
cadavers was processed by von Hagens Plastination
platysma continue over the mandible, without skeletal
in the axial, sagittal and coronal planes using their
attachment, to insert directly into the buccinator and the
latest technique (n = 10; male = 4; female = 6; mean
orbicularis oris muscle at the modiolus. The DLI was
age: 67 years).[12]
confirmed to be part of the platysma layer, being entirely
(3) High-resolution micro-CT of the mandibular area was
continuous with it (including the same direction of muscle
performed on two hemifaces of one cadaver to
fibres) and with no overlap being present between these
confirm the anatomy in a three-dimensional way
two muscles. Removal of the DAO, which overlies both
(male, 67 years).[13]
muscles, demonstrated this continuity (Fig. 3, Video 2).
The only firm attachment of the musculoaponeurotic
layer (Layer 3) to the mandible was that of these three
Results muscles, which we considered to be the ‘‘mandibular
ligament’’ of the deep plane, more for descriptive purposes.
The anthropometric results of the mandibular area are The mean extent of this mandibular ligament starting
shown in Table 1. The series of standardized anatomical from the midline was 63.1 mm in men and 59.3 mm in
dissections demonstrated that the jowl is a localized area of women, corresponding with the location of maximal jowl
redundant skin and subcutaneous fat, that the anterior fullness, not the anterior border of the jowl (Table 1). The
border of the jowl and labiomandibular crease is not mean distance from the posterior end of the mandibular
defined by a specific osteocutaneous ligament but by there ligament to the masseter muscle attachment was a mere 5.2
being a change in subcutaneous connective tissue organi- mm. Moreover, in two cases there was no space between
zation, and that the deep part of the mandibular ligament is the two, and in one case, they even overlapped with the
the unique combined attachment of the platysma, DLI and masseter attaching inferior and the platysma, DLI and
DAO into the mandible which actually underlies the jowl DAO attaching superior on the mandible (Fig. 4.A).
partly, not borders it anteriorly. The sheet plastination
confirmed these observations, while the histology and Superficial Part of the Mandibular Ligament
micro-CT results demonstrated the true anatomical nature
of the jowls. In the subcutaneous plane, no significant ligaments were
identified. The retinacula cutis fibres attaching the skin to
The Jowl the platysma are not denser/thicker in the area overlying
the deep mandibular ligament than in the surrounding
The jowl is situated entirely in the supra-platysmal plane, subcutaneous tissues. Instead of providing stout fixation,
as redundant subcutaneous tissue with overlying skin. The the subcutaneous retinacula cutis septa are longer in the
maximal jowl fullness corresponds with the area over the area of the jowl than in other areas, which allows

123
Aesth Plast Surg (2023) 47:170–180 173

Table 1 Measurements on the jowl, mandibular ligament and relevant structures obtained from a standardized series of dissections on twelve
fresh (non-frozen) cadavers

Mean (mm) SD (mm) Range (mm)

Midline—Mental Tubercle 13.0 3.8 9 - 19

Midline—Corner of Mouth 34.4 3.9 29 – 40
Midline—Marionette Crease 40.6 4.1 35 – 47
Midline—Posterior extent of Mandibular Ligament 61.7 4.9 52 – 68
Midline—Gonial Angle 113.2 7.4 101 – 123
Posterior extent of Mandibular Ligament—Masseter Muscle 5.2 5.0 -6 – 10
Posterior extent of Mandibular Ligament—Mental Foramen 21.8 2.3 19 – 26
Posterior extent of Mandibular Ligament—MMN (n. VII) 1.5 0.5 1–2
Midline—Anterior Jowl Border 40.3 3.6 33 – 44
Midline—Maximal Jowl Fullness 61.1 6.9 48 – 72
Midline—Posterior Jowl Border 78.5 8.3 67 – 98
Gonial Angle—Anterior Jowl Border 68.2 11.3 48 – 91
Gonial Angle—Maximal Jowl Fullness 49.2 9.4 33 – 69
Gonial Angle—Posterior Jowl Border 30.7 8.0 19 – 50

significant mobility of the skin over the fixed platysma resistance. For the untrained eye this might appear as ‘‘skin
(Fig. 5). However, when performing a deep subcutaneous tethering’’ but this is, in fact specifically ‘‘muscle tether-
dissection at the lower trunks of these retinacular fibres, the ing’’ (Video 3).
flap does appear more tethered to the platysma over this
area than over the surrounding areas. This is not because of The Labiomandibular Fold and Crease
the presence of a strong ligament in the subcutaneous
connective tissues, but because the platysma at this loca- The labiomandibular crease represents the start of the so-
tion is tethered by its attachment to the mandible. Whereas called perioral adhesion zone where the upper and lower
traction on the flap in all other areas results in gliding of the lip muscles insert directly into the dermis. This dermal-
platysma over the deeper tissues, in contrast to traction muscle adhesion starts at the alar base to include the lip
over the deep mandibular ligament, which is met with levator muscles forming the nasolabial crease, continues

123
174 Aesth Plast Surg (2023) 47:170–180

submental crease. The net effect of these muscles inserting

into the dermis is a radical change in the subcutaneous
layer (Layer 2). Whereas lateral to the crease the subcu-
taneous fat allows mobility of skin over the muscles,
medial to the crease the skin and mimetic muscles are
adherent and move as one entity. Sheet plastination con-
firmed this configuration (Fig. 6).
The labiomandibular fold is most defined just inferior to
the modiolus, where the platysma emerges from under-
neath the DAO and inserts directly into the skin and into
the orbicularis oris muscle (Fig. 6A). When following the
crease inferiorly, it becomes less distinct, partially over-
lying the DAO. Here, the DLI and mentalis muscles are
seen inserting into the dermis in a more diffuse way
(Fig. 6B).

Fig. 2 The deep part of the mandibular ligament is the combined Marginal Mandibular Nerve
mandibular attachment of the platysma, depressor labii inferioris
(DLI) and the depressor anguli oris (DAO). It has a specific
A wafer of deep fat is consistently seen overlying the
organization with the platysma attaching most caudal, the DLI
attaching most cephalad and the DAO attaching in the middle. The mandible between the bulk of the masseter muscle and the
posterior part of the platysma also inserts directly into the buccinator mandibular ligament (Fig. 4B). This fat also covers the
and the modiolus. The middle part of the platysma ‘‘disappears’’ deep anterior extension of the masseter muscle, which is often
to the DAO to ‘‘reappear’’ at its medial border and insert into the
overlooked. The following structures were consistently
lower lip dermis and orbicularis oris muscle. This part was previously
called the ‘‘depressor labii lateralis’’ by Le Louarn.[23] The fixed visualized within this wafer of fat: the facial vein posteri-
anterior part of the platysma inserts into the mandible as part of the orly, the facial artery anteriorly, and the MMN crossing
mandibular ligament but then continues further to the lower lip under both vessels superficially. The main branch of the MMN
the name ‘‘depressor labii inferioris’’, which is embryologically and
was always in intimate relation with the mandibular liga-
evolutionary part of the platysma muscle. When dissecting in the deep
plane, it is the posterior end of the platysma attachment which can be ment, passing 1 - 2 mm from it to continue cephalad to the
felt as the ligament when palpating the flap anteriorly ligament still deep to the platysma, DLI and DAO (Fig. 4C,
Video 2).

Discussion

This unique anatomical study, with initial exploratory

dissections and macro-sectioning, a series of standardized
layered dissections complemented by histology, sheet
plastination and micro-CT has clearly clarified the fol-
lowing structures: the jowl is redundant subcutaneous tis-
sue with its overlying skin, not bordered anteriorly by an
osteocutaneous mandibular ligament but by the perioral
adhesion zone of direct lower lip muscle insertion into the
dermis. The mandibular ligament proper is present only in
the deep (sub-platysmal) plane and extends underneath the
jowl up to the level of the maximal jowl fullness, not to the
Fig. 3 This right side of a fresh cadaver demonstrates the lower lip anterior border of the jowl. The MMN branch passes the
depressors. Removal of the depressor anguli oris (DAO) demonstrates mandibular ligament in a much more intimate position than
the continuity of the platysma as the depressor labii inferioris (DLI),
being a continuation of the same muscle
was previously suggested.

over the anterior part of the modiolus and the superomedial Functional Anatomy
border of the DAO forming the labiomandibular crease to
finally include the transversus menti muscle forming the The entire mandibular anatomy in the jowl area reflects the
complex functional requirements necessary for opening the

123
Aesth Plast Surg (2023) 47:170–180 175

complex lip movement (Fig. 7). In addition, humans have

mimetic muscles of the lower lip (depressors), which
attach in a relative broad area onto the mandible, being
approximately 3 cm posterior to a vertical line though the
oral commissure.

Opening the Mouth

The mean opening of the mouth (and thus lowering of the

mandible) in the Caucasian population is approximately 5
cm (range 3.7 – 6.7 cm).[14] While the chin and lower lip
skin simply follows the mandible, the position of the oral
commissure and especially the cheek does not lower by the
same amount. Lowering of the mandible therefore needs to
be largely independent from the soft tissues in order to
prevent the cheek to be pulled down during mouth opening.
In humans, the area where the mandible must glide inde-
pendent from the soft tissues is much larger than in most
other species due to the narrow mouth (Fig. 7). Further-
more, the broad mandibular attachment of mimetic muscles
in humans causes these muscle origins to be dragged along
when lowering the mandible. As the lip depressors elon-
gate, the overlying skin which lacks this intrinsic stretching
capability needs to allow the underlying muscles and
mandible to glide. This need for gliding requires a spe-
cialized subcutaneous connective tissue arrangement in this
Fig. 4 Fresh cadaver dissections of the right mandible. A The mean
area, not a firm immobile osteocutaneous ligament (Fig. 8).
distance from the posterior end of the platysma attachment to the
masseter is 5.2 mm (SD = 5.0 mm), but in some cases, such as the one
seen here, the two muscle attachments ‘‘overlap’’, with the platysma, Development of Jowls
DLI and DAO taking origin superior and the masseter taking origin
inferior on the mandible. B Repositioning the deep fascia over the
The functional anatomy may explain how the formation of
mandible demonstrates there is a wafer of fat overlying the mandible
and masseter posterior to the mandibular ligament (also clear in C.). the jowl is related to the necessity for skin gliding.
Coursing vertically through this fat are the facial vein posteriorly and Whereas in youth, the subcutaneous connective tissue is
the facial artery anteriorly with the marginal mandibular nerve elastic and shorter, in due time with aging, it loses this
(MMN) crossing both vessels superficially. The fat over the nerve has
elasticity and lengthens, resulting in secondary subcuta-
been removed to enhance visualization. The main branch of the MMN
is always in close relationship with the mandibular ligament, passing neous laxity that constitutes the jowl. The jowl is maximal
it at only 1 - 2 mm to then continue forward, cephalad to the ligament overlying the most posterior part of the mandibular liga-
towards the mentalis, still deep to the platysma, DLI and DAO. ment, as most gliding of the skin over the muscles occurs
C With the upper part of the platysma, DLI and DAO flipped over to
here. Towards the chin, the necessity for skin to glide
reveal what is behind, the continuation of the main branch of the
MMN is visualized passing towards the mentalis muscle. The mental lessens and thus waning of the jowl anteriorly. Posterior to
nerve is seen exiting the mental foramen at approximately 22 mm the mandibular ligament, gliding of the mandible occurs
from the end of the mandibular ligament mostly in the sub-platysmal plane (premasseter space),
reducing the necessity for skin to glide and thus waning of
mouth, mastication and mimetic activity. All these actions the jowl posteriorly (Video 1). No individual gliding of the
require slightly different planes of mobility and points of skin over the muscle is possible nor necessary over the area
attachments, which explain the effects seen with aging in of the perioral adhesion zone.
this region, i.e. the jowl.
The Mandibular Ligament
Speech and Mimicry
Since its first description in 1989, most clinicians were
In contrast to other mammalian species, humans have a satisfied with the concept that an osteocutaneous ligament
relatively narrow mouth and commissures to allow must mark the anterior border of the jowl. Since then,
research regarding this idea has focused on uncovering the

123
176 Aesth Plast Surg (2023) 47:170–180

Fig. 5 Overview of the subcutaneous soft tissue organization at the skin to glide over the mandibular ligament when opening the mouth.
level of the jowl approximately at the most posterior end of the Note how the retinacula cutis are oriented downwards with the mouth
mandibular ligament. Typical (A) histology with the mouth closed closed, but upwards with the mouth open, allowing the gliding of the
and (B) micro-CT with the mouth open, of the jowl demonstrates the mandible and muscle attachment underneath. When dissecting in the
enormous mobility of the skin and subcutaneous fat in this area. deep subcutaneous plane, the length of these retinacula cutis cannot
Instead of a stout ligament in the subcutaneous layer, the retinacula be perceived as they are cut at their base (trunk), and they can be
cutis connecting the skin to the muscles over the mandibular ligament perceived as subcutaneous ‘‘mandibular ligaments’’
are longer than in the other supra-platysmal areas. This allows the

Fig. 6 Sheet plastination sections through three planes of the chin labiomandibular crease or fold can be pinpointed. Whereas posteri-
region demonstrate the shift from loose areolar tissue in the normal orly, the dermis is loosely connected to the muscles, this connection
cheek and neck tissues to dense adhesion of the lower lip muscles and becomes more defined at the anterior third of the DAO, with thicker
the dermis in the perioral adhesion zone. A Axial section through the and shorter retinacula cutis. At the anterior border of the DAO, the
cephalad part of the lower lip. Observe the retinacula cutis fibres DLI also starts inserting directly into the lower lip skin. C Sagittal
connecting the dermis to the muscle are longer in the cheek, abruptly section of the chin segment showing the relatively uniform tight
shortening anteriorly in the perioral region over the DAO to become attachment of the dermis that maintains the soft tissue connection
absent medial to the DAO. B Axial section through the caudal part of with the mandible on movement. Note the abrupt change in the neck
the lower lip demonstrates a more subtle transition and no real inferior to the submental crease

123
Aesth Plast Surg (2023) 47:170–180 177

was consistently discovered much further posterior than the

anterior border of the jowl: it was identified along the entire
fixed platysma.[9]

The Labiomandibular Fold and Crease

Our anatomical study confirms previous reports that the

labiomandibular crease is not caused by an osteocutaneous
ligament but simply marks the start of the insertion of the
lower lip muscles into the dermis similar to the nasolabial
crease of the upper lip (i.e. perioral adhesion
zone).[10, 11, 18–20] In addition to the report of Pessa
et al. describing DAO inserting into the dermis superiorly
in the crease, this study showed that (from superior to
inferior) platysma, DLI and mentalis add to this dermal
insertion along the superomedial border of the DAO.[10]
Whereas the crease is very well defined superiorly, the
inferior extent is not.

Marginal Mandibular Nerve

Fig. 7 This illustration comparing the human to the dog illustrates The standardized set of anatomical dissections in our study
how much soft tissue needs to glide over the mandible posterior to the reliably located one branch of the MMN in much closer
oral commissure for the jaw to open. The human has a very narrow proximity to the mandibular ligament than previously
mouth combined with a broad mimetic muscle attachment (platysma,
DLI, DAO). This combination requires for skin to glide over this area suggested. Whereas Huettner et al. described its presence at
(or rather the mandible and muscle attachments to glide under the a mean distance of 9.7 mm from the subcutaneous
skin), eventually creating the jowl ‘‘mandibular ligament’’, we found it consistently present in
close proximity, only 1-2 mm from the deep mandibular
true nature and location of this ligament. However, the pres- ligament.[7] The explanation for the disparity in the find-
ence of an osteocutaneous ligament at this location would ings from Huettner et al. is understandably due to the
impair mouth opening by directly tethering the mandible to different depth of dissecting the mandibular ligament. The
the midcheek skin and via the skin to the zygoma. ligament we isolated and consider to be the real mandibular
Our study provides clear evidence that the mandibular ligament is in the deep plane, whereas Huettner’s plane of
ligament exists only in the deep plane (sub-platysmal) as dissection was in the subcutaneous plane. As the MMN
the muscular attachment of the platysma, DLI and DAO to runs in the deep plane (sub-platysmal), to visualize the
the mandible, not in the subcutaneous plane. Interestingly, MMN required the removal of a strip of overlying pla-
this pattern of attachment of these muscles to the mandible tysma, DLI and DAO to then measure the distance from the
had already been described in classic anatomical text- ‘‘deep’’ MMN to the ‘‘subcutaneous’’ mandibular ligament.
books.[15, 16] In the subcutaneous layer, the long reti-
nacula cutis provided mobility rather than fixation. Implications for Rhytidectomy
Interestingly, this organization is remarkably similar to the
mandibular septum described by Reece, Pessa and Correction of the jowl by a deep-plane, sub-platysmal
Rohrich.[17] lower facelift technique might seem counterintuitive in the
Skin tethering as seen during a subcutaneous dissection presence of the mandibular attachment of the platysma
at this location may mimic a subcutaneous mandibular impairing lifting the platysma and overlying anterior part
ligament but was clearly demonstrated to be nothing more of the jowl. However, the laxity of the elastic platysma
than a reflection of the underlying muscle tethering to the muscle sheet allows significant lifting despite its
mandible. The lack of a true osteocutaneous ligament mandibular attachment, with the overlying tissues being
explains the large variety of descriptions of subcutaneous redraped and the jowl effaced by this manoeuvre. The
mandibular ligaments by previous authors who were improvement of the jowl obtained using the deep-plane
looking to define a subcutaneous ligament in this area. This (sub-platysma) lower facelift technique thus results from
understanding also explains why the mandibular ligament tightening the laxity of the elastic platysma superior to its
attachment. This lift is transmitted through the retinacula

123
178 Aesth Plast Surg (2023) 47:170–180

Fig. 8 This illustration demonstrates how the different areas across the mandible-muscle complex at the common mandibular attachment
the mandible react to opening of the mouth. At the premasseter space of the platysma, DLI and DAO. At the perioral adhesion zone (red),
(blue), opening the mouth results in gliding of the platysma over the opening the mouth results in en-bloc movement of the mandible,
masseter without need for additional skin gliding. At the mandibular lower lip muscles and the skin, maintaining constant relationships
ligament (yellow), opening the mouth requires the skin to glide over

cutis to reduce the overlying dermal laxity, which flattens Limitations of the Study
the jowl to a significant degree.
The release of the true (deep) mandibular ligament can The cadavers studied were all from a similar age (range 56
only be done through a subperiosteal release of the broad – 97). As the jowl appears and progresses over time, it
ligament, e.g. through a submental incision. This is because would be ideal to study the development of the jowl
releasing the mandibular ligament in the deep plane carries throughout aging done on groups of cadavers of different
too much risk due to the close proximity of the MMN and ages. Sheet plastination was only obtained in three planes,
is therefore not recommended. Release of the ‘‘mandibular axial, sagittal and coronal. Ideally, a plane perpendicular to
ligament’’ in the subcutaneous plane is simply releasing the the mandible would be used. Histological investigations
connection of the dermis of the anterior jowl to the mus- required the removal of the mandible and after laying the
culoligamentous attachment of the platysma, DLI and sample flat on a cardboard for fixing. Ideally, the anatomy
DAO. Unlike the idea that this happens at the anterior would be investigated with the tissues undisturbed, e.g.
border of the jowl, this actually occurs along the anterior with decalcification of the mandible in situ.
half of the jowl which explains why this manoeuvre is
successful: it was never clear before how it could be ben-
eficial to release a ligament anterior to the jowl when the Conclusion
redraping is posterior. Instead, what is actually released is
the tethering of the skin over the mandibular ligament at The jowl, a stigmatizing sign of aging in humans, results
the anterior half of the jowl. This release may be indicated from aging of the constantly moving subcutaneous tissues
(1) to tighten submental laxity from the lateral approach or and skin overlying the mandible. The presence of this
(2) to release a significant residual skin crease in this area, mobile tissue in humans results from the evolution of the
using the submental approach.[21, 22] mouth and its mimetic muscles. The mandibular ligament

123
Aesth Plast Surg (2023) 47:170–180 179

proper is not osteocutaneous nor stout, as it does not have a long as you give appropriate credit to the original author(s) and the
stout subcutaneous component, nor does it constitute the source, provide a link to the Creative Commons licence, and indicate
if changes were made. The images or other third party material in this
anterior border of the jowl. It is present only in the deep article are included in the article’s Creative Commons licence, unless
plane and is a different name for the mandibular attach- indicated otherwise in a credit line to the material. If material is not
ment of the mimetic muscles (platysma, DLI and DAO) included in the article’s Creative Commons licence and your intended
and is present under the anterior half of the jowl. The use is not permitted by statutory regulation or exceeds the permitted
use, you will need to obtain permission directly from the copyright
labiomandibular crease is not formed by a ligament, holder. To view a copy of this licence, visit http://creativecommons.
instead it relates to the insertion of the lower lip depressors org/licenses/by/4.0/.
into the dermis. The MMN is in direct proximity of the
mandibular ligament, and release of the mandibular liga-
ment in the deep plane is contraindicated. Release of a References
‘‘mandibular ligament’’ at the anterior border of the jowl is
a misconception. 1. Mendelson BC, Freeman ME, Wu W, Huggins RJ (2008) Sur-
gical anatomy of the lower face: the premasseter space, the jowl,
Supplementary InformationThe online version contains and the labiomandibular fold. Aesthet Plast Surg 32:185–195.
supplementary material available at https://doi.org/10.1007/s00266- https://doi.org/10.1007/s00266-007-9060-3
022-02996-3. 2. Reece EM, Rohrich RJ (2008) The aesthetic jaw line: manage-
ment of the aging Jowl. Aesthet Surg J 28:668–674. https://doi.
Acknowledgements The authors acknowledge the donors and fam- org/10.1016/j.asj.2008.09.007
ilies of the Body Donor Programs of the University of Melbourne, 3. Furnas DW (1989) The retaining ligaments of the cheek. Plast
Queensland University of Technology and Yonsei University who Reconstr Surg 83:11–16. https://doi.org/10.1097/00006534-
have made this study possible. Specific thanks go to Matt Wissemann 198901000-00003
and Ian Mellor of the Medical Engineering Research Facility (MERF) 4. Stuzin JM, Baker TJ, Gordon HL (1992) The relationship of the
for their assistance in the laboratory and Assoc. Prof. Quentin Fogg superficial and deep facial fascias: Relevance to rhytidectomy
from the University of Melbourne and Prof. Cameron Brown from the and aging. Plast Reconstr Surg 89:441–449. https://doi.org/10.
Queensland University of Technology for their supervision. The 1097/00006534-199203000-00007
authors thank Tae-Hyeon Cho of the Department of Anatomy of the 5. Özdemir R, Kilinç H, Ünlü ER et al (2002) Anatomicohistologic
Yonsei University College of Medicine for providing high-resolution study of the retaining ligaments of the face and use in face lift:
micro-CT scans. Also, Ms Erica Mu and Dr Darryl Whitehead from retaining ligament correction and SMAS plication. Plast Reconstr
the School of Biomedical Sciences of The University of Queensland Surg 110:1134. https://doi.org/10.1097/01.prs.0000021442.
and Rory Bown and Felicity Lawrence from the CARF Histology 30272.0e
Laboratory at the Queensland University of Technology for providing 6. Alghoul M, Codner MA (2013) Retaining ligaments of the face:
the pristine histology outcomes. The authors are grateful for the help review of anatomy and clinical applications. Aesthet Surg J
of Dr Vladimir Chereminskiy and Daniela Albinus from von Hagens 33:769–782. https://doi.org/10.1177/1090820x13495405
Plastination for providing high-quality sheet plastination slices. 7. Huettner F, Rueda S, Ozturk CN et al (2015) the relationship of
Specific thanks go to Dr Naveen Somia and Dr Tim Papadopoulos for the marginal mandibular nerve to the mandibular osseocutaneous
revision of the manuscript. ligament and lesser ligaments of the lower face. Aesthet Surg J
35:111–120. https://doi.org/10.1093/asj/sju054
8. Kang MS, Kang HG, Nam YS, Kim I-B (2016) Detailed anatomy
Funding Open Access funding enabled and organized by CAUL and
of the retaining ligaments of the mandible for facial rejuvenation.
its Member Institutions. All authors declare that they have nothing to
J Craniomaxillofac Surg 44:1126–1130. https://doi.org/10.1016/j.
disclose. No funding was received for this article.
jcms.2016.06.018
9. Langevin CJ, Engel S, Zins JE (2008) Mandibular ligament
Declarations
revisited. In: Presented at the annual meeting of the Ohio Valley
Society of Plastic Surgeons. Cleveland, Ohio. May 2008.
Conflict of interest The authors declare that they have no conflicts of 10. Pessa JE, Garza PA, Love VM et al (1998) The anatomy of the
interest to disclose. labiomandibular fold. Plast Reconstr Surg 101:482–486. https://
doi.org/10.1097/00006534-199802000-00037
Ethical Approval Ethical approval for the project was granted by the 11. Sandulescu T, Franzmann M, Jast J et al (2019) Facial fold and
Human Ethics Advisory Groups of the University of Melbourne for crease development: a new morphological approach and classi-
the exploratory study, the Queensland University of Technology for fication. Clin Anat 32:573–584. https://doi.org/10.1002/ca.23355
the definitive study including histology and plastination, and the 12. Hagens GV (1979) Impregnation of soft biological specimens
Yonsei University College of Medicine for the micro-CT study with thermosetting resins and elastomers. Anatomical Rec
(Project numbers 14243, LR2021-4306-4761, and YSAEC22-004). 194:247–255. https://doi.org/10.1002/ar.1091940206
13. O. J, Kwon H-J, Cho T-H, et al (2021) Micro-computed
Informed Consent For this type of study, informed consent is not tomography with contrast enhancement: an excellent technique
required. for soft tissue examination in humans. PLoS ONE 16:e0254264.
https://doi.org/10.1371/journal.pone.0254264
Presented at ISAPS 2021 World Congress in Vienna, Austria. 14. Mezitis M, Rallis G, Zachariades N (1989) The normal range of
mouth opening. J Oral Maxil Surg 47:1028–1029. https://doi.org/
Open Access This article is licensed under a Creative Commons 10.1016/0278-2391(89)90174-2
Attribution 4.0 International License, which permits use, sharing, 15. Bannister LH, Berry MM, Collins P (1995) Gray’s anatomy, 38th
adaptation, distribution and reproduction in any medium or format, as edn. Churchill Livingstone, London

123
180 Aesth Plast Surg (2023) 47:170–180

16. Lightoller GH (1925) Facial muscles: the modiolus and muscles 21. Connell BF, Gaon A (1983) Surgical correction of aesthetic
surrounding the Rima Oris with some remarks about the Pan- contour problems of the neck. Clin Plast Surg 10:491–505
niculus Adiposus. J Anat 60:1–85 22. Marten TJ (2008) High SMAS facelift: combined single flap
17. Reece EM, Pessa JE, Rohrich RJ (2008) The mandibular septum: lifting of the jawline, cheek, and midface. Clin Plast Surg
anatomical observations of the jowls in aging—implications for 35:569–603. https://doi.org/10.1016/j.cps.2008.04.002
facial rejuvenation. Plast Reconstr Surg 121:1414–1420. https:// 23. Louarn CL (2016) A new approach to functional anatomy of the
doi.org/10.1097/01.prs.0000302462.61624.26 lower face: Role of the hyoplatysmal ligament, of the platysma
18. Ghassemi A, Prescher A, Riediger D, Axer H (2003) Anatomy of and of the depressor labii lateralis. Ann De Chir Plastique
the SMAS revisited. Aesthet Plast Surg 27:258–264. https://doi. Esthétique 61:101–109. https://doi.org/10.1016/j.anplas.2015.12.
org/10.1007/s00266-003-3065-3 002
19. Gardetto A, Dabernig J, Rainer C et al (2003) Does a superficial
musculoaponeurotic system exist in the face and neck? An Publisher’s Note Springer Nature remains neutral with regard to
anatomical study by the tissue plastination technique. Plast jurisdictional claims in published maps and institutional affiliations
Reconstr Surg 111:664–672. https://doi.org/10.1097/01.prs.
0000041538.49139.11
20. Kwon H-J, Cho TH et al (2020) The Nasolabial fold: a micro-
computed tomography study. Plast Reconstr Surg 145:71–79.
https://doi.org/10.1097/prs.0000000000006328

123