Analysis of Cervical Angle in the Submental Muscular Medialization and Suspension Procedure

Abstract

Importance

The submental muscular medialization and suspension (SMMS) procedure is an option for addressing an obtuse cervical angle in select patients vs the use of traditional rhytidectomy techniques.

Objective

To compare the change in position of the cervical point between groups undergoing SMMS vs the traditional rhytidectomy technique.

Design, Setting, and Participants

A retrospective review was performed of 141 patients undergoing rhytidectomy in an accredited private surgery center between January 1, 2013, and December 31, 2014, comparing cervical point depth between patients undergoing SMMS vs those undergoing traditional rhytidectomy with platysma plication. Statistical analysis was performed from November 11, 2017, to January 5, 2018.

Interventions

Patients underwent either SMMS or traditional rhytidectomy with platysma plication.

Main Outcomes and Measures

The primary end point was change in the cervical point distance between preoperative and postoperative standardized profile photos.

Results

A total of 141 patients were included in the analysis. A cohort of 46 patients (43 women and 3 men; mean age, 63.5 years [range, 49.0-79.0 years]) underwent neck contouring with the SMMS technique and a cohort of 95 patients (90 women and 5 men; mean age, 61.0 years [range, 48.0-73.0 years]) underwent traditional rhytidectomy with platysmaplasty. The cervical point distance of the SMMS cohort had a mean (SD) postoperative increase of 2.0 (1.05) cm (95% CI, 1.73-2.28; P < .001) compared with 0.78 (0.82) cm in the traditional rhytidectomy cohort (95% CI, 0.54-1.02; P < .001).

Conclusions and Relevance

The results of this study suggest that submental muscular medialization and suspension appears to be an effective option to address the obtuse neck in select patients.

Level of Evidence

3.

This cohort study compares the change in position of the cervical point between groups undergoing the submental muscular medialization and suspension procedure vs those undergoing the traditional rhytidectomy technique.

Key Points

Question

Does the submental muscular medialization and suspension procedure produce greater improvement of the cervical angle in select patients vs traditional rhytidectomy techniques?

Findings

In this cohort study of 141 patients undergoing rhytidectomy, analysis of the change in cervical point position after submental muscular medialization and suspension revealed a statistically significant 2-cm increase in point depth.

Meaning

In select patients with obtuse cervicofacial angle and large submental fat pads, the submental muscular medialization and suspension technique appears to be an effective option to improve cervical point depth and cervicofacial angle.

Introduction

In the last several decades, rhytidectomy techniques have undergone continuous refinements. Despite this evolution, inferiorly displaced hyoid bones, large submental fat pads, and diastasis of the midline neck musculature often limit optimal improvement of the cervical region of the face. It has been the practice of one of us (P.R.L.) for the last decade to address some conditions of obtuse cervical angle with the submental muscular medialization and suspension (SMMS) technique.

Submental muscular medialization and suspension uses the removal of midline subplatysmal fat to expose the medial borders of the anterior digastric muscles. The borders of platysma and anterior digastric musculature are then medialized and suspended posteriorly and superiorly to the mylohyoid fascia using suture plication. In appropriate candidates, the resultant repositioning of the cervical point yields an increased acuity of the cervicomental angle.

The SMMS technique has been detailed in previous publications by Langsdon and Moak.¹ However, at the present time, to our knowledge, there are no studies comparing results of SMMS vs traditional rhytidectomy with platysma plication. In addition, many previous studies evaluating neck contouring techniques have used subjective assessment methods, including patient satisfaction and independent ratings of youth, attractiveness, success, and health.² To increase objectivity in evaluating postoperative results, this study assessed cervical point position as a surrogate for hyomental distance and the cervicomental angle. Cervicomental angle and hyomental distance have both been used in prior studies to objectively analyze outcomes in rhytidectomy.³

Methods

A retrospective observational analysis was undertaken of all consecutive patients undergoing rhytidectomy between January 1, 2013, and December 31, 2014. Selection criteria included patients receiving rhytidectomy with cheek and neck lift, with or without concomitant procedures. Patients undergoing isolated cervicofacial liposuction without platysmaplasty, neck contouring without submental incision, or adjunct chin implantation were excluded. Those with less than 1 year of follow-up were also excluded from the analysis. Patients meeting the inclusion criteria were divided into the following 2 cohorts: those undergoing rhytidectomy with SMMS and those undergoing rhytidectomy with traditional platysmaplasty. Group characteristics and the surgical outcomes of the 2 cohorts were compared. Institutional review board approval was obtained from the University of Tennessee Health Science Center and a waiver of patient consent was granted by this board because the research involved no more than minimal risk to the patient and could not be predictably carried out without such a waiver.

Age, sex, follow-up period, complications and postoperative change in cervical point depth were analyzed. All cases were performed by one of us (P.R.L.) at a private, state-licensed, Medicare-certified surgery center. Standardized, 5-view rhytidectomy photographs were recorded before surgery and throughout the follow-up period. Cervical point depth was used as a marker for surgical outcome. The cervical point was measured before and 1 year after surgery for all patients. Lateral view photographs taken in horizontal Frankfurt plane were used for assessment of the cervical point. The cervical point depth was determined by creating a 90° right angle between a horizontal line drawn through the deepest cervical point and a vertical line passing through the fixed bony landmarks of the subnasale and pogonion (Figure 1). The postoperative change in horizontal limb distance from the cervical point was measured and compared between the 2 cohorts. All photographs were standardized in terms of focal length and distance to the camera. Photographs were assessed using Mirror software (Canfield Scientific).

Figure 1. Technique for Measuring Change in Cervical Point Distance.

A, Before surgery. B, After surgery. A vertical line is drawn from the subnasale through the pogonion. A horizontal limb is drawn 90° tangential to the vertical, through the deepest cervical point. The difference in horizontal limb length represents the change in cervical point distance.

Description of Surgical Techniques

In the traditional rhytidectomy with platysma plication performed by one of us (P.R.L.), the submental area is addressed through a 2.5-cm incision. Subcutaneous elevation of the skin is completed widely and inferiorly, just beyond the thyroid notch, with sharp and blunt dissection. A 4-mm liposuction cannula is used for superficial liposuction of preplatysmal fat. If significant submental fat pad is present, limited lipectomy in the midline can be completed. A strip of the dehisced midline platysmal fascia is then removed and platysmal bands, if present, are divided as low as the thyroid cartilage. Interrupted, buried mattress sutures are next used to plicate the medial borders of the platysma, similar to corset platysmaplasty.⁴ The skin is closed with a running, locking suture.

The SMMS technique (Figure 2) differs from the above technique. In the SMMS technique, after the exposure of the medial borders of the platysma muscle, a layer of subplatysmal fat is removed and the mylohyoid fascia is exposed at the deep extent of the dissection and the anterior digastric musculature is exposed at the lateral extent. A thin layer of fat superior to the digastric muscles, when present, can also be removed with judicious liposuction. The mylohyoid muscle is now exposed between the medial borders of the anterior bellies of the digastric muscles. The resultant void after subplatysmal fat excision is closed by plicating and suspending the medial borders of the digastric muscles with interrupted, buried sutures. A total of 2 to 3 sutures are needed to complete the plication from just above the hyoid to the submental crease.^1,5 Plication of the digastric musculature results in posterior and superior displacement of the cervical point. Platysmal plication is then completed, with deep portions of each suture suspending to the deeper digastric muscles. Additional lateral cutaneous undermining is used to correct any cutaneous bunching.

Figure 2. Submental Muscular Medialization and Suspension (SMMS) Technique.

A, Exposure of preplatysmal fat. B, Excision of preplatysmal fat. C, Excision of subplatysmal fat with exposure of the digastric muscles and mylohyoid fascia. D, Suture medialization of the digastric muscles with suspension to the mylohyoid fascia. E, Suture medialization of the digastric muscles with suspension to the mylohyoid fascia. F, Suture medialization of the platysma. G, Before SMMS; H, After SMMS. The images were created by and reproduced with the permission of Phillip R. Langsdon, MD.

Statistical Analysis

Statistical analysis was performed from November 11, 2017, to January 5, 2018. All results were analyzed using IBM SPSS Statistics, version, 24 (IBM Corp). Standard t test was used to compare the change in cervical point position of patients who underwent SMMS with those undergoing traditional facelift with platysmaplasty. All P values were from 2-sided tests and results were deemed statistically significant at P < .05.

Results

A total of 141 patients met inclusion criteria and were included in the analysis. Forty-six patients (32.6%) underwent neck contouring with the SMMS technique (43 women and 3 men; mean age, 63.5 years [range, 49.0-79.0 years]) and 95 patients underwent traditional rhytidectomy (90 women and 5 men; mean age, 61.0 years [range, 48.0-73.0 years]). A decision to perform SMMS was made by one of us (P.R.L.) for patients considered to have significant anatomical variations that were unlikely to be corrected with traditional rhytidectomy. Palpation of substantial midline deep subplatysmal fat in the presence of an obtuse cervical angle was used to determine the possibility of angle improvement. All patients who met inclusion criteria were included in the final analysis, with no loss to follow-up.

The cervical point distance measured from the pogonion showed a mean (SD) increase postoperatively of 2.0 (1.05) cm (95% CI, 1.73-2.28; P < .001) compared with 0.78 (0.82) cm in the non-SMMS group (95% CI, 0.54-1.02; P < .001).

Two patients in the SMMS group (4.3%) required early needle aspiration for a small submental serosanguinous accumulation, as did 5 patients (5.3%) in the non-SMMS group. One patient in each group required opening of the submental incision for evacuation. There were no cases of facial paralysis in either group. Two patients in the SMMS group (4.3%) and 4 patients in the non-SMMS group (4.2%) required the application of nitroglycerin, 2%, ointment (Nitro-Bid; Fougera Co) 3 times a day for decreased perfusion of the posterior skin flap. No patient had skin loss or permanent scarring requiring reoperation. No patient required surgery for scar revision.

Discussion

Despite years of evolution in rhytidectomy techniques, a subgroup of patients characterized by an inferiorly positioned hyoid, large submental fat pad, and an obtuse cervicofacial angle often have less than desirable improvement in the cervical angle after traditional rhytidectomy. It has been the practice of one of us (P.R.L.) to use the SMMS technique to achieve improved results in properly selected patients. Patients were selected for this technique either by presurgical palpation of subplatysmal fat between the base of the tongue and hyoid or on discovery during the surgical procedure. Despite anecdotal success with this technique, to our knowledge, no study currently exists that objectively compares the results of SMMS technique with those of traditional rhytidectomy techniques.

The results of this investigation support the notion that application of the SMMS technique in select patients can aid in achieving an improved cervicomental angle beyond that achievable with traditional rhytidectomy techniques. Patients undergoing the SMMS technique during the time period defined in the study achieved a mean (SD) posterior displacement of the cervical point of 2.0 (1.05) cm, compared with a mean (SD) posterior displacement of 0.78 (0.82) cm in those undergoing standard rhytidectomy technique using platysma plication. The posterior displacement of the cervical point increases the acuity of the cervicomental angle, a critical feature of the youthful neckline.

Removal of the subplatysmal, submental fat pad and medialization of the anterior digastric muscles distinguishes this technique from traditional plastysma plication techniques. Accordingly, the void created and filled by plicating the medial borders of the platysma and digastric muscles likely accounts for the increases in the cervical point distance identified in the study. This increase in distance can be particularly robust in patients with a large subplatysmal medial fat collection, as has been the experience of one of us (P.R.L.) (Figure 3).

Figure 3. Patient Before and 12 Months After Rhytidectomy With Submental Muscular Medialization and Suspension, Upper Eyelid Blepharoplasty, and Lower Eyelid Blepharoplasty .

A, Before surgery. B, After surgery. Note the change in cervical point and acuity of the cervicomental angle.

The technique has its limitations. Although the subplatysmal fat can be addressed in the midline, it is not technically practical to attempt eradication of subplatysmal fat very far lateral to the anterior digastric muscles. In addition, despite posterior and superior anchoring of the midline muscular tissue, hyoid position still places a limiting factor on the degree of improvement that can be obtained. Thick anterior digastric muscles may also limit improvement. However, these muscles may be shaved with sharp and electrocautery dissection to reduce muscle bulk. Despite these limitations, the SMMS technique still provides superior results for select patients compared with traditional techniques, with no concomitant increase in the risk or complication profile of the procedure.

Failure to medialize and suspend the deep musculature after removal of the fat between the deep surface of the platysmal muscle plane and the mylohyoid fascia may result in a deep cervical concavity. Failure of the suspension-medialization suture may also result in a concavity. It is the routine of one of us (P.R.L.) to use either a nonresorbable suture such as a large-diameter Ethibond (Ethicon) or a long-lasting absorbable suture such as 2-0 or larger polydioxanone (Ethicon). One of us (P.R.L.) abandoned the use of quickly absorbable suture such as Vicryl (Ethicon) because of the development of a midline diastasis in the year before this study.

Another factor limiting maximal outcome is the patient with advanced tissue elasticity loss, such as those with advanced age and severe musculocutaneous ptosis. In any patient with advanced tissue ptosis who is undergoing rhytidectomy, it is our normal practice to remind patients of the possible need for a rhytidectomy tuck up procedure as early as 1 year after surgery because of the degradation of youthful tissue elasticity. This is especially important in candidates for the SMMS procedure because lateral cervical resagging will enhance any slight submental concavity. Therefore, when faced with advanced musculocutaneous ptosis, advanced age, and an obtuse cervical angle resulting from ptosis and subplatysmal fat, performing secure deep plane cheek elevation, careful submental SMMS sculpting, and a planned 1-year repeated superior advancement of cheek flaps may be necessary to achieve optimal results.

Limitations

This study is limited in the selection bias of patients undergoing the SMMS technique. As not all patients require the implementation of the SMMS technique, it is impossible to truly randomize patients to treatment groups. The experience and expertise of the surgeon in evaluating a patient’s anatomy with consideration of his or her desired results is paramount to determining the intervention most suitable. This limitation was mitigated to the best of our ability with use of a large sample size and evaluation of all patients during the study to provide for the broadest range of presurgical neck condition. Intuitively, one would expect that surgical results would improve as the surgeon’s familiarity with the technique increased. Our results may be on the higher end of the spectrum of expected outcomes using this particular technique.

Conclusions

The SMMS technique has been used to help address suboptimal outcomes from traditional rhytidectomy in patients with an obtuse cervical mental angle. The technique, using the removal of the midline subplatysmal fat with medialization and superior suspension of the midline neck musculature, has provided improved anecdotal results in the past. This study objectively verifies a significant increase in the distance of the cervical point achieved using the SMMS technique compared with rhytidectomy with platysma plication alone. The SMMS technique should be considered an appropriate option to achieve desirable results in properly selected patients with large submental fat pads, a low-lying hyoid bone, and diastasis of the deep, midline neck musculature and an obtuse cervical angle.