Thread lifting, or suture suspension, is a facial rejuvenation technique in which practitioners insert and pass one or more threads under the skin surface, pull to lift the ptotic tissue and anchor the threads at the site of entry.1-6 This technique has been studied for more than 20 years.7
The goal of thread lifting is to reposition soft tissue (such as superficial fat pads) without undermining tissue, while maintaining safety and producing sustainable results.7,8 Middle-aged patients with mildly/moderately ptotic tissues and good skin quality have been considered ideal candidates for thread lift procedures.9 Traditionally, patients with heavy tissues or thin skin have not been considered candidates, but I have found that the technique described below overcomes many of these shortcomings.9
Since the practitioner’s technique is the bridge between basic science and clinical outcome, optimising each step in thread placement is essential for success.
Step-by-step protocol
Superficial fat pads are the targets and mediators of tissue repositioning.9 The technique for repositioning these pads is based on vectors created by volumisation (i.e. restoring facial volume in a specific area) and tissue-engaging polydioxanone (PDO) threads.9,10 When a superficial fat pad is located in the fixed-masticatory area of the face, lifting vectors are created through volumisation.9,10 For example, when the lateral orbital superficial fat pad is volumised and anchored by the zygomatic retaining ligament, both a vertical vector and an oblique medial vector are created.9,10
Superficial fat pads located in the mobile-mimetic zone of the face, however, are better repositioned with oblique vectors created by tissue-engaging PDO threads rather than volumisation.9 I have observed that each time I place a tissue-engaging thread, whether knowingly or by default, I go through 12 steps/decisions to properly reposition the target tissue. These are outlined below, offering practitioners a possible framework against which to align their own thread lifting practice with any kind of thread.
1. Identify the target structure
The anatomical structure and its characteristics form the basis for selecting the design, material and length of the thread.11 In my experience, four conditions determine the holding power and length of the thread to be used. If the superficial fat pads in the mobile area of the face are to be repositioned, the threads are anchored to the superficial fat pad in the fixed masticatory area of the face. The cogs and barbs of the thread are attached to the fibrous septa present in superficial fat, retinaculum cutis superficialis, retaining ligaments and septa, and the superficial fat is used to advance the cannula.
The thread must have sufficient holding power (for example, at least 1kg of linear tension to prevent the pad from slipping) and a length approximately equal to the target structure. Depending on the size of the fat pad, a 60mm thread is appropriate to reposition the narrow nasolabial sup fat pad, and an 80-100mm thread is suitable to reposition the jowl fat pad.9-11
2. Know the anatomy of the thread
A bidirectional thread has five components: the trim zone, lifting cogs, intermediate area without cogs, anchoring cogs and disengagement component (the majority of threads in use are bidirectional).9 Familiarity with the position of each component helps the practitioner to know the anatomical structures in contact with each component.
3. Select an appropriate entry point
Depending on the structure to reposition, the entry point may be proximal, middle or distal to the structure.12,13 I have found that a proximal entry point provides more control over the target, avoids having to circumvent the curvature of the facial skeleton and adapts better to the repositioned fat pad without causing the skin to fold (Figure 1).
4. Determine the lifting vector
The practitioner needs to determine the number, direction and magnitude of the lifting vector. One vector is sufficient to reposition a single fat pad as adding more vectors only increases structures to lift but does not improve efficacy. More weight to lift increases the risk that the repositioned pad will slip, and a single vector requires only one tract for anaesthesia.9,14
As for direction, oblique is preferred because it distributes the weight of the fat pad between the cogs and stem of the thread; the latter is the sturdiest part of the thread with a typical tensile strength of 10 newtons. If the direction of the lifting vector is vertical, all the tension falls on the cogs, thus increasing the risk that the pad will slip out of place.15
According to the triangle law of vector addition, the magnitude of the vector must overcome the weight of the fat pad and its attachments (dermis and SMAS), muscular forces, gravity and the holding tension over time (Figure 1).16 Magnitude can be achieved by dividing the main vector into a proportional number of additive sub-vectors with entry points along the main vector.16
5. Place the escalating sub-vectors
In my approach, each sub-vector is obtained by placing one thread, and then another through the same entry point. The second thread reduces the holding tension of the first thread, allowing the practitioner to tie and tighten a knot. The knot and the lifting cogs of the first and second thread work together to lift the fat pad. To reduce the holding tension of the first sub-vector, a second sub-vector is inserted into a second entry point and follows the same direction as the main vector. The addition of this sub-vector also helps to stabilise the system. The total number of sub-vectors is proportional to the magnitude of forces needed to keep the fat pad at its new position.
6. Place the fat pad in the ultimate position
Before placing the cannula, the practitioner should envision and create a blueprint for the final result. The cannula should meet the fat pad at its ultimate location, and be placed in relation to surrounding structures (Figure 2). As long as you are in the right plane, there are no specific areas to be avoided, but one should be careful in the temporal and marginal mandibular nerve danger zones. I have observed that if tissues are manipulated after the thread is released, wrinkles or dimples may appear on the skin.9
7. Decide how the cannula should advance
If cogs on the thread have a helicoid distribution, the practitioner should advance the cannula linearly. If the cogs are distributed in a single plane, the cannula should be rotated while advancing to improve its septal engagement.9 When using an L-tip cannula, if the width of the septal opening coincides with the width of the cog, there is a larger chance that the cog will not engage the septum. By rotating the cannula, different septal opening designs are created, thus increasing the chance for septal engagement.
8. Advance the cannula
The delta lift depends on how far from the entry point the last anchoring cog is placed. In my practice, I have seen that the greater the distance, the greater the lift.10
9. Spread the facial skin along the cannula
Once the tip of the cannula reaches the most distant point and before releasing the thread, I advise that the practitioner should spread/ reposition skin along the cannula to avoid the development of a skin wrinkle (Figure 3).
10. Maintain the golden ratio
I have found that before releasing a thread, the practitioner should be certain that the superficial fat pad is in its desired and final position, the lifting and anchoring cogs are in contact with the correct structures and the skin is repositioned correctly.9 Failure to position these items correctly will result in wrinkles or dimples, as I have observed.
11. Trim the excess smooth thread
Trimming the smooth thread all the way to the first lifting cog avoids any discomfort, which is often associated with leaving the smooth area of the thread in the mobile part of the face. This can also lead to thread extrusion and poking of the skin.
12. Aim to elicit a mechanobiological adaptation
Fat pad lifting occurs in three stages. During the first three months (Stage 1), lifting depends on the mechanical interaction of tissue-engaging thread and tissue.4,17 Between three and nine months (Stage 2), lifting depends on tissue adhesion secondary to the fibrotic response generated by the thread material and thickness.18 After nine months (Stage 3), fat pad repositioning depends on the mechanobiological adaptation of the retaining ligaments.18 The latter mechanism is triggered by changing the tension profile of retaining ligaments over a long period of time.18 These mechanical signals, through transduction, result in increased collagen production (at high tension) or reduced collagen production (at low tension) as described in Figure 4.18
Contraindications for treatment
Absolute contraindications for thread lifts are infection/inflammation at the proposed treatment site, pregnancy and unrealistic patient expectations, as these can lead to dissatisfaction and patient wellbeing should be prioritised.19 Relative contraindications are thin skin and heavy tissues, but advanced thread practitioners may still be able to treat such patients with experience and detailed knowledge of the facial nerve and vessel anatomy.19
Achieving optimal results
The facial rejuvenation technique described here provides a step-by-step guide to repositioning fat pads of the face by thread lifting to obtain optimal, long-term results with minimum discomfort to the patient. The exact duration of threads’ effectiveness depends on the exact technique used: if the lifting effect is only due to mechanical tissue, results will last about three months; if the lifting effect is carried by tissue adhesion caused by a biological response, results could last six to 12 months; and if a mechanobiological adaptation of supporting structures is created, results can last over a year.9
Through adherence to these 12 steps, I have achieved successful outcomes for more than 1,300 patients, with varying duration dependent on thread type.
