The Misunderstanding of Posterior Tongue Tie Anatomy and Release Technique

When medical providers and parents hear the phrase “tongue tie”, they most commonly picture a tight anterior tongue tie, where the tip of the tongue is tacked down to the floor of the mouth. I have previously described the difference between anterior and posterior tongue tie (PTT) but the concept still eludes many people. One of the most common statements I hear from medical professionals is that “posterior tongue tie doesn’t exist”. The most basic reason why people claim to not “believe” in PTT (as if it were a spiritual issue rather than an anatomical one) is that they know very little about breastfeeding and the relationship with tongue tie. Some of this sentiment comes from a blatant misunderstanding of the anatomy (they think the tie is in the posterior oral cavity near the tonsils). Others don’t understand the concept because they don’t know what normal infant tongues do during breastfeeding (as shown in ultrasound studies). Finally, most medical providers don’t understand proper examination technique, which prevents them from correlating the symptoms with abnormal anatomy.

There are some published data on the presence of PTT. Cliff O’Callahan and colleagues, in a 2013 paper, treated 299 babies with tongue tie. 84% of those babies had PTT; this number includes babies who previously had an anterior tie that was snipped by a different medical provider. Nevertheless, the majority of babies that presented to his office did not have an anterior tie. Dr. O’Callahan demonstrated clinically significant improvements in breastfeeding quality with a frenotomy. To those who don’t believe that PTT exists, I use this study to demonstrate that release of a tongue tie with no anterior frenulum results in clear clinical improvement. A more recent study from 2015 by Pransky and colleagues retrospectively evaluated 618 babies presenting with breastfeeding symptoms. In this study, almost 20% had PTT alone and a further 5% had both PTT and a lip tie. As is the case with the O’Callahan study, the vast majority of babies in this study showed improvement in breastfeeding quality following frenotomy.

A posterior tongue tie is the presence of abnormal collagen fibers in a submucosal location surrounded by abnormally tight mucous membranes under the front of the tongue. As I wrote in a previous post, a classic anterior tongue tie always has a posterior component behind it. Therefore, any tongue tie causing breastfeeding problems is truly a posterior tongue tie; a percentage of those ties also have an anterior component. Failure to release all of the abnormal collagen fibers results in persistent tongue restriction. When providers claim to release 80-90% of the restriction, the dyad can often see 0% improvement. The other major misconception that people have about PTT anatomy is the idea that the tie is somehow “deep” and that it intertwines with the muscles of the tongue. This is not the case. As seen in the diagrams below, the abnormal collagen fibers of the PTT are intertwined within the mucous membrane covering the tongue muscles. The muscle of the tongue beneath this mucous membrane (the genioglossus muscle) is in a completely different tissue layer and is therefore not involved in tongue tie anatomy nor does it need to be involved in the release procedure.

View fullsize

PTT fibers are centrally located in a layer above the genioglossus muscle

View fullsize

A small window is made through the PTT fibers to begin the release

View fullsize

Release of the mucous membrane on either side of the central window

View fullsize

Final diamond-shaped wound is achieved (top half of wound seen here)

Incomplete release of a tongue tie prevents the tongue from achieving its normal movements during breastfeeding. A common fallacy is that a tongue cannot be tied if it can extend out of the mouth beyond the gumline or lips. This is completely untrue. First, the tongue is capable of numerous different movements, and normal mobility in one direction does not guarantee normal mobility in all directions. Furthermore, the motion of the tongue during breastfeeding is very specific - the primary movement that is important is up, not out. I wrote about breastfeeding mechanics, where we have objective evidence from Donna Geddes’ paper in 2008 (and later corroborated by David Elad’s paper in 2014) demonstrating the importance of the upward motion of the tongue. The lack of strong upward movement, inhibited by a tongue tie’s abnormal collagen fibers restricting the tongue to the floor of mouth or mandible, is shown in common symptoms: poor suction/seal on the breast, frequent breaking of the seal with resultant clicking, air intake (aerophagia), slipping off the breast and having to bite down to hold on to the nipple and so forth. These symptoms can occur with bottle feeding as well.

With an understanding of the normal movement of the tongue during breastfeeding, the medical provider and lactation consultant MUST change how they examine the baby. Without challenging the upward movement of the tongue, they will never understand if a visible and palpable restriction exists. I have previously written about proper examination technique to try and standardize our approach to infant oral examinations.

Along with the misconceptions about PTT anatomy come misconceptions about PTT release. Many able and skilled providers combine a poor examination technique with apprehension about PTT release. Why is there apprehension about the procedure? The most common reason is the misunderstanding of how deep one must travel to fully release the tethered fibers. As I stated above, the PTT fibers intertwine with the mucous membrane and do not involve the muscle. Proper release technique involves a central release of the fibrous band and then a release of the mucous membrane on either side of the central band. One must release the mucous membrane lateral to the band (resulting in a diamond-shaped wound) because the mucous membrane around the tie has shrink wrapped around the muscle to only allow the movements that were present prior to the tie release. Once the central band is released, you must also release the mucous membrane to allow the tongue to actually move up. The actual depth of the initial incision is surprisingly shallow (approximately 1mm). Neither the central release nor the lateral mucosal releases involve the muscle, so bleeding is kept to a minimum. Also contrary to popular belief, a PTT can be released with scissors or laser - the release technique described above is far more important than the tool used.

View fullsize

Looking from the top down, the grooved director lifts the tongue out of the way, isolating the posterior tongue tie

View fullsize

After central release is made, the mucous membrane release on one side is started

View fullsize

Release is carried to other side

View fullsize

Final diamond-shaped wound is achieved with higher lift with the grooved director

I sincerely hope this post helps to clarify PTT anatomy and to demystify the procedure needed to release tongue ties properly. If you are a clinician reading this and would like additional pictures, videos, or descriptions of the procedure, please email me using the link at the top of my page. For parents, using this post may help your doctors understand PTT anatomy and that a tie can occur without an obvious visible frenulum. For clinicians looking to improve their clinical skills, I highly recommend shadowing a provider who performs this procedure frequently (and for those inclined, you may shadow me by contacting me). This improved understanding of PTT will decrease the number of inadequately released frenula and improve long term breastfeeding success.

The Importance of Active Wound Management Following Frenotomy

One of the more common discussion threads surrounding tongue/lip tie division is the topic of wound reattachment, where dyads exhibit brief windows of symptom resolution only to reverse their progress and return to the original problems with breastfeeding. This post will explain the principles of a complete tongue/lip release, the biology of wound healing, and the necessity for actively managing a wound to prevent scarring.

Frenotomy Wounds

An appropriate procedure for the lip or tongue will result in a complete release of tension caused by the inappropriately tight fibrous band. The best way to know if a proper release has been done is to look at the shape of the wound. For lingual frenotomies, there must be a diamond-shaped wound for the release to be complete. If there is no diamond-shaped wound, then the procedure hasn't fully released the tension. For the upper lip, complete laxity of the central lip should be seen and the tie should be completely lifted off of the gumline. If only a small nick in the lip tie or tongue tie is made, there will be little to no chance of improvement because the wound itself is small. Along the same lines, if the initial procedure was incomplete and scar tissue forms, the wound did not “reattach” - it was just incompletely opened. In contrast, a fully opened wound will pathologically reattach if active wound management isn’t practiced. This pathologic reattachment is different than the typical attachment we see when the tongue or lip heal normally. What we are aiming for is a band that is more flexible and forgiving than what was there prior to the procedure.                            

This sketch of the release of a lip tie shows the result of proper wound management, where a finger is gently run under the lip to separate the lip from the gumline, versus poor wound management, where too much of the lip is allowed to readhere to the gumline. Remember, if the initial release was inadequate, then you would never have achieved the good mobility in the first place, so it can mimic the reattached lip.

The tongue tie wound is more complex. First, just snipping an anterior frenulum does little to improve tongue function for breastfeeding purposes. There is always a posterior, submucosal component of the tongue tie that needs to be released. If the procedure stops short and only the anterior part of the tie is released, no open wound under the tongue results. There must be a diamond-shaped wound in order to have a full release of a tongue tie. After an incomplete procedure, stretches are irrelevant because the size of the wound created is minimal, so it will heal with minimal scarring.  The problem in this scenario is that the tension of the posterior tongue tie is still present and function doesn’t improve. What we want is a procedure that fully releases the tension and doesn’t reattach. This can only be achieved by actively stretching the wound. My protocol for that is here.

Principles of Wound Healing

While some of the principles of wound healing inside the mouth also apply to wounds on the skin, there are certain characteristics that are unique to oral wounds. The best description of these characteristics is in the book “Oral Wound Healing” by Hannu Larjava (2012). When a wound is created, it will undergo specific, predictable changes in an attempt to close that wound. Within 24 hours of wound creation, the edges of the wound begin to migrate towards the center of the wound so that the edges can try and eventually zipper together with a mucous membrane covering. This migration is facilitated by a scaffolding that forms over the wound (this is the white/yellow color we see as an oral wound is healing).  At the same time, granulation tissue begins to fill the wound. Granulation tissue serves to reform the connective tissue that gives the new wound strength. It does this by migrating new blood vessels into the area and forming a matrix of fibers that are the precursors to scar formation. It can take months for the mature wound to finally form. During this time, wound contraction occurs as the scar fibers organize.

How does this apply to tongue tie and lip tie? When a provider creates a wound in the mouth to try and release a tethered band, the mouth will try close that wound. In the context of tongue tie and lip tie, we want those wounds to heal in an open conformation rather than closed back together. It is also important to translate this expected progression of wound healing into what should visibly happen to the wounds. Lip releases heal extremely well and aren’t typically subjected to what happens under the tongue. It is important, however, to understand that there will be a new band connecting the lip to the gumline - that's part of normal lip healing. For the tongue, the first 5-7 days following a frenotomy demonstrate a soft wound with good mobility. As time goes on, the diamond under the tongue will start to contract and get firm. This is most prevalent between days 10-21 after a procedure. The scar tissue developing within the diamond will ultimately loosen again after day 21, and can take months to fully soften and mature.

View fullsize

Horizontal vs Vertical Healing

Remember, once an open wound is created in the mouth, the body will try to close the wound and contract toward its center. The end result is that the lip will try to stick back down to the gumline and the tongue will try to stick back down to the floor of mouth. The trick to achieving optimal results is to try and guide the tissue, through proper stretches, to heal in a way that maximizes vertical movement. This vertical movement is important for upward flanging of the lip and more importantly, upward movement of the tongue towards the palate to form the seal necessary for vacuum generation.

Tools and Techniques

To my knowledge, there haven’t been any published studies that demonstrate superior wound healing outcomes with a particular surgical technique or instrument. Some laser studies show potential benefits when studied in the lab or in animal models, but so far no human studies exist that demonstrate a difference. What is important to recognize is that the tool being used for the procedure really doesn’t matter. What matters is the depth of the release - an adequate release resulting in a diamond-shaped wound needs stretching regardless of the instrument that was used to create the wound.

Why do some wounds behave poorly and result in inflexible scar formation? There are many potential reasons:

1. The release was inadequate from the beginning so scar tissue forms on top of already immobile tissue    
2. Poor adherence to wound stretching protocols
3. Poor surgical technique - cutting too deep (muscle damage) and stimulating a more rigorous inflammatory response
4. Delivery of too much energy to the wound, either by the inadequately trained laser provider who turns a 45 second procedure in a much longer exposure to laser energy or laser settings that are inappropriate
5. Inherent scar forming tendencies of the patient

While the success of the procedure doesn’t come from the tool used, my experience has been that the use of electrocautery causes more collateral damage (when compared to laser or scissors), resulting in more scarring. There are always exceptions to this rule, so it is important to know how to choose your provider appropriately.

The most successful approach to tongue/lip tie revision includes:

1. The IBCLC, who helps to establish better latch mechanics and positioning in addition to improving sucking skills
2. A therapist to help resolve muscle tension which can inhibit both the latch and proper wound healing
3. The provider, who should create a proper wound and manage the healing in a way to maximize the mobility of the lip and/or tongue 

This multidisciplinary approach is the key to successful rehabilitation from a problematic nursing relationship.

How to Take Appropriate Pictures for Tongue Tie or Lip Tie Evaluation

This post has one basic goal: to teach you how to take appropriate pictures of the tongue or lip to help others evaluate your baby from a distance.

1) taking good pictures requires 2 people. A tongue selfie does no one any good. One person lifts the lip or the tongue and the other snaps the picture.

2) get good illumination - a decent LED headlight now costs less than $20.

3) Proper positioning - the lip and the tongue should move up for normal breastfeeding. Getting your fingers under the lip or under the tongue is important for testing if you can easily pick the tongue up. Position yourself from above so that the baby's feet are moving away from you.

4) Here’s a video on how to elevate the lip or the tongue: https://vimeo.com/

5) For the person taking the picture, make sure you position yourself so you can bring the entire frenulum in view. One trick is to have the focus already set by focusing on the mouth before you do the elevation. On iPhones (and possibly Android phones), holding your finger on the desired area of focus for several seconds will result in a locked “autofocus/autoexposure”, so that it won’t try to refocus as the baby moves. Another trick is to just hold the shutter down and take a rapid burst of photos to see if you can find a suitable picture. Along similar lines, you could take a video and then choose a screen shot later.

Tongue tie vs lip tie: which is more to blame?

As awareness about the impact of tongue tie and lip tie on breast-feeding has become more widespread, more and more people are having questions about how to best evaluate babies with breastfeeding problems. Many people focus on lip tie as the major problem with breastfeeding. I receive many pictures of babies' lips from parents who are wondering whether a simple lip revision will take care of their problems.

Why is there such a focus on the lip? I have several theories:

1) It's an easy structure to evaluate.

2) Many parents and practitioners are confused about the difference between a normal labial frenulum and a lip tie. I've written about that previously.  

3) The procedure and the recovery are relatively easy. The stretching exercises for the lip are well-tolerated and the reattachment rate is extremely low. 

Wouldn't it be great if such a simple lip procedure took care of so many problems? I do think that the upper lip plays a role in normal breast-feeding. With a lip tie, the child has difficulties flanging the upper lip, and this can cause muscular tension that can make opening the mouth widely very difficult. The result is a shallow latch, a small mouth (baby can't open widely), nipple pain and nipple trauma. In my experience, if a baby comes to my office with breastfeeding problems and has a tie, 99% of the time that child will have a tongue tie. They may also have a lip tie (about 50-60% of the time) accompanying the tongue tie but isolated lip tie is very uncommon - it makes up less than 1% of the babies that I treat. Those few babies have normal tongue function; the lip restriction is the only obstacle to achieving a normal latch. For most babies, however, a tongue restriction is the problem.

Why do I think that the tongue is usually to blame?

1) The tongue is the active muscle in breastfeeding. It is responsible for the creation of negative pressure that is necessary to nurse normally. The lip, on the other hand, is a relatively static/passive component of normal breastfeeding. It can get in the way, but a normal lip doesn't guarantee normal feeding. A normal tongue, on the other hand, is much more predictive of normal breastfeeding. 

2) Almost every published paper demonstrating the benefit of frenotomy on breastfeeding included patients who only had a tongue tie release. Most ignored the lip. Despite ignoring the lip, the available evidence shows that lingual frenotomy alone was beneficial. 

3) When the tongue is tethered, it can affect the lip's function. If the tongue does not form the peristaltic wave necessary for vacuum generation, the baby can forcefully try to suck the breast in. This can cause the upper (and lower) lip to get sucked in, again causing the mouth to stay closed. This can mimic a lip tie because many people equate a rolled-in lip with a lip tie when it's really the tongue's fault. Think of the lip motions necessary to use a straw: the lips must purse with strength to hold suction. In people with facial paralysis (like with Bell's Palsy or who have suffered a stroke), they are unable to purse the lips on the affected side and the suction is weak and liquid can dribble out. How does this relate to a baby? If a baby's tongue isn't working appropriately, they will often purse their lips to hold on tightly to the breast - this can result in the upper (and lower) lip turning in, even if there's no true lip tie.

Remember, most of the symptoms common to tied children are caused by the tongue's inability to move up: clicking, poor suction, poor breast drainage, leaking out the sides of the mouth, slipping to the end of the breast, popping on and off the breast, poor weight gain, falling asleep prematurely only to wake up hungry later, reflux/colic symptoms and pain/nipple trauma. The one major overlapping symptom set with isolated lip ties occurs in moms who have lots of pain and nipple damage without the other tongue symptoms. If the tongue has good superior movement in the mouth, then I will treat the upper lip alone and wait to determine if something else needs to be done.

If a practitioner focuses on a lip tie without evaluating the tongue or determines that the tongue is "normal" even in the presence of the aforementioned symptoms of tongue restriction, it may be an indication of inadequate education or experience in diagnosing or treating tongue ties. In my mind, the tongue should be the first place a practitioner should look before even worrying about the lip. Quite often, I will only treat the tongue if I'm not sure of the impact of the lip on the breastfeeding relationship. In those instances, I usually never see those babies back because the tongue release alone is sufficient to improve that relationship.