Safety and complications of absorbable threads made of poly‐L‐lactic acid and poly lactide/glycolide: Experience with 148 consecutive patients

Effective Management of Thread Misplacement in Thread Lifting Procedures: A Clinical Case Utilizing the Hook for Extraction

Thread lifting is a popular nonsurgical procedure for skin rejuvenation, utilizing bioabsorbable barbed threads inserted into subcutaneous or deeper structures such as the superficial musculoaponeurotic system. Despite its efficacy, complications such as thread misplacement can occur, leading to adverse outcomes such as dimpling, inflammation, and scar formation. This article presents a clinical case involving a 32-year-old woman with a superficially placed thread following a thread-lifting procedure. Using a specialized instrument, the N-Hook, the thread was successfully extracted through a minimally invasive technique. The procedure ensured the complete removal of the thread without complications, restoring patient satisfaction.

An Assessment and Comparison of Adverse Effect Rates in Differing Absorbable Thread Lift Suture Materials

BACKGROUND

Thread lifting, a minimally invasive alternative to facial rhytidectomy, has shifted from using nonabsorbable to absorbable sutures. Although many thread lift options exist, the impact of these different properties on complication rates remains unclear.

OBJECTIVE

To systematically compare thread lift complication rates across different suture materials, textures, fixation methods, and lift locations.

MATERIALS/METHODS

A systematic review was conducted through February 2024, following PRISMA guidelines, using multiple databases. The study focused on absorbable sutures, excluding nonabsorbable materials. Statistical analysis used Chi-Square tests with Bonferroni correction.

RESULTS

Nineteen studies, encompassing 1,406 patients, met inclusion criteria. A total of 876 complications were reported. Ecchymosis (19.49%), swelling (16.79%), and tenderness (9.96%) were the most frequent complications, while hematoma (0.64%), paresthesia (1.14%), and infection (2.49%) were least frequent. Complications varied significantly among the studied factors. Swelling and ecchymosis were more associated with polycaprolactone sutures, barbed threads, and midface lifts. Barbed threads were associated with more complications than smooth or coned threads, as were floating threads compared with fixed threads.

CONCLUSION

Variations in thread lift suture materials and fixation technique were associated with different complication rates. Thread lifts using absorbable sutures exhibited complication rates under 5%, suggesting a generally favorable safety profile.

Efficacy of Lifting Threads Composed of Poly(L-Lactide-Co-ε-Caprolactone) Copolymers Coated With Hyaluronic Acid: A Long-Term Study on Biorevitalizing Properties in Skin Remodeling

BACKGROUND

Facial thread lifting, which is popular in aesthetic medicine because of its minimal invasiveness, has led to advancements in the use of biodegradable polymers such as poly(L-lactide-co-ε-caprolactone) (P(LA/CL)) and its hyaluronic acid-coated variant (P(LA/CL)-HA). These developments enhance biocompatibility and efficacy, offering prolonged benefits through better biostimulation and tissue integration.

METHODS

A controlled experiment involving five 4-month-old female pigs compared the effectiveness of P(LA/CL) and P(LA/CL)-HA threads over six months. After being implanted into the subcutaneous layer parallel to the skin of each pig, the threads were evaluated through histological analysis at intervals (7, 21, 30, 90, and 180 days) to assess changes in dermal and hypodermal structures, collagen types, elastin levels, and tissue integration via stains such as hematoxylin and eosin (H&E), Weigert-Van Gieson, and Sirius Red.

RESULTS

P(LA/CL) and P(LA/CL)-HA threads significantly led to dermal and hypodermal remodeling. By day 180, a comparative analysis via the Wilcoxon test revealed that P(LA/CL)-HA significantly outperformed P(LA/CL) in most histological indicators because of the biostimulatory effects of hyaluronic acid.

CONCLUSIONS

Our study investigated the effects of two types of bioabsorbable threads, P(LA/CL) and P(LA/CL)-HA, on skin remodeling over 180 days in a porcine model. These results highlight the significant role of thread composition in tissue remodeling and suggest that incorporating HA could optimize therapeutic and aesthetic outcomes. Further clinical research is necessary to confirm these findings in human subjects.

Engineering of Bioresorbable Polymers for Tissue Engineering and Drug Delivery Applications

Herein, the recent advances in the development of resorbable polymeric-based biomaterials, their geometrical forms, resorption mechanisms, and their capabilities in various biomedical applications are critically reviewed. A comprehensive discussion of the engineering approaches for the fabrication of polymeric resorbable scaffolds for tissue engineering, drug delivery, surgical, cardiological, aesthetical, dental and cardiovascular applications, are also explained. Furthermore, to understand the internal structures of resorbable scaffolds, representative studies of their evaluation by medical imaging techniques, e.g., cardiac computer tomography, are succinctly highlighted. This approach provides crucial clinical insights which help to improve the materials' suitable and viable characteristics for them to meet the highly restrictive medical requirements. Finally, the aspects of the legal regulations and the associated challenges in translating research into desirable clinical and marketable materials of polymeric-based formulations, are presented.

Efficacy and Safety of Fillers for the Treatment of Nasolabial Folds: A Network meta-Analysis of Randomized Controlled Trials

BACKGROUND

Nasolabial fold formation is increasingly becoming a cause of concern for many people. However, no network meta-analysis has compared the efficacy of different fillers in treating nasolabial folds. This network meta-analysis simultaneously compared the efficacy and safety of various fillers.

METHODS

We included randomized controlled trials (RCTs) that used fillers to treat nasolabial folds. We extracted data of Wrinkle Severity Rating Scale (WSRS), Global Esthetic Improvement Scale (GAIS, investigator) scores, GAIS scores (self-reported) and adverse events.

RESULTS

We included 13 RCTs. WSRS scores at 6 months were higher in patients receiving HA than those receiving poly (L-lactic acid) (mean difference [MD] 0.630, 95% confidence interval [CI] 0.275, 0.985) but significantly lower in patients receiving HA than in those receiving bovine collagen (MD - 0.580, 95% CI - 0.777, - 0.383) and porcine collagen (MD - 0.525, 95% CI - 0.790, - 0.260). Regarding adverse events, HA was significantly less likely to cause nodule formation compared with bovine collagen (RR 0.593, 95% CI 0.438, 0.803).

CONCLUSION

HA is a safe filler for correcting nasolabial folds, and poly (L-lactic acid) showed potential in treating nasolabial folds.

LEVEL OF EVIDENCE I

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Immediate effect of different herbal solutions on tensile strength of suture materials in oral cavity

This pilot study evaluated the immediate effect of different herbal solutions in oral use on the tensile strength of the sutures used in oral surgical procedures. Three frequently used suture materials, polyglactin 910 (PGA), poliglecaprone (PGCL), and polypropylene (PP), were chosen in a 4-0-gauge size. The sutures' tensile stress was evaluated before being immersed (baseline) and after immersion at 24 h, 1 week, and 2 weeks in four different media: artificial saliva, chlorhexidine, Commiphora myrrh, and frankincense. The tensile strength was assessed by applying a 50 N load at a standardized speed of 2 mm/min. The data were analyzed using one-way and three-way analysis of variance (ANOVA) and the Tukey post hoc test with a significance level of p ≤ 0.05 significance level. The mean values of the maximum load showed a significant statistical difference across the three types of sutures (PGA, PGCL, and PP). The mean tensile strength of the PP suture was statistically lower than that of the other sutures. There was a statistically significant difference in the mean tensile strength of the PGA suture when stored in chlorohexidine media and the PGCL suture for frankincense media. The tensile strength for all sutures was the lowest value when immersed in Commiphora myrrh media. Home-prepared herbal solutions can affect the tensile strength and maximum load of suture materials. Careful and controlled use of herbal solutions after any dental surgical procedures is advisable.

What are filling (volumizing) threads?

Facial aging prompts a shift in the demands for lifting procedures, transitioning from targeted improvements in younger individuals to overall facial contour enhancements as skin elasticity declines in later years. This paper examines the evolution of PDO volumizing threads, delineating their development from initial limitations to contemporary innovations aimed at addressing tissue deformation and maintaining thread integrity post-insertion. Categorizing these threads based on elasticity, shape, and functionality underscores their versatility and application nuances, catering to specific wrinkle correction, contour sculpting, and facial volume restoration. The discussion emphasizes the pivotal role of thread characteristics in achieving optimal outcomes while minimizing potential complications. By delving into historical contexts, mechanisms, effectiveness, and thread classification, this paper equips practitioners with a comprehensive understanding to make informed decisions in selecting threads for volumizing thread procedures. Recommendations for future research directions, including long-term safety assessments and patient-specific outcomes, seek to enhance the clinical utility and applicability of this analysis.

Ultrasound-guided thread lifting for the prevention of parotid gland and diagnosing parotid duct complications

BACKGROUND

Thread lifting is a common minimally invasive plastic surgery procedure. Parotid gland injury caused by thread lifting is a known complication; however, visual evidence of this complication is lacking.

OBJECTIVES

This study aimed to present cases of parotid gland injury by thread lifting shown using ultrasound and to discuss the importance of ultrasound detection of the location of the parotid gland before thread insertion.

METHODS

This study included eight patients diagnosed with parotid gland perforation and one with parotid duct injury due to threads from November 2020 to October 2022.

RESULTS

Six patients showed tenderness and swelling, three were asymptomatic, and one with duct injury showed severe swelling and pain. Although the severity and duration of symptoms have differed, we confirmed the progress of improvement with conservative treatment and confirmed ultrasound findings progressed.

CONCLUSIONS

Using ultrasound to detect the parotid gland's location before thread lifting might reduce the chance of parotid duct injury. Identifying immediate parotid duct or gland injury with ultrasound can help to act quickly for delayed pain or swelling and reduce the likelihood of additional complications.

Antimicrobial Photodynamic Therapy in the Approach of Complication After Implantation of Spiculated Polydioxanone Threads

The present manuscript is a clinical case report in which antimicrobial photodynamic therapy (aPDT) - using a low-power laser (660 nm) associated with methylene blue photosensitizer (0.01%) - was considered for treating a case of complication after implantation of spiculated polydioxanone (PDO) threads, an aesthetic procedure worldwide performed in facial cosmetic non-surgical procedures. A 72-year-old female patient presented an infection in the face region where the PDO thread was implanted (mandible angle). After divulsion and local drainage, it was decided to associate aPDT using a low-level laser associated with a 0.01% methylene blue photosensitizer. Two sessions of aPDT were performed - on sequential days - and within 48 hours the region was dry and without signs of secretion. The use of aPDT seems to be a promising and effective option in cases of infections after implantation of PDO threads, consisting of a safe technique, of low execution complexity and without adverse effects.

Cosmetic dermatology in menopause

ABSTRACT

Skin changes that accompany aging lead many to seek treatments that restore a more youthful appearance. Common issues of concern include skin tone, wrinkles, skin thinning, sagging, laxity and decreased elasticity, and hollowing of the face. This work discusses these concerns and their anatomic bases and highlights evidence for a causal role played by menopause-associated hormonal changes where such evidence exists. In addition, treatment options are discussed, with an emphasis on minimally invasive approaches. A variety of modalities are discussed, including botulinum toxins, fillers, multiple types of lasers, radiofrequency devices, focused ultrasound, chemical peels, and thread lifts. These interventions, often in combination, can achieve goals of patients seeking aesthetic rejuvenation.

Safety of Aesthetic Medicine Procedures in Patients with Autoimmune Thyroid Disease: A Literature Review

Autoimmune thyroid diseases are the most common organ-specific autoimmune diseases, affecting 2-5% of the world's population. Due to the autoimmune background of thyroid diseases, we analyzed a wide range of cosmetic procedures, from minimally invasive cosmetic injections (mesotherapy) to highly invasive procedures, such as lifting threads. Out of the seven categories of treatments in aesthetic medicine analyzed by us-hyaluronic acid, botulinum toxin, autologous platelet-rich plasma, autologous fat grafting, lifting threads, IPL and laser treatment and mesotherapy-only two, mesotherapy and lifting threads, are not recommended. This is due to the lack of safety studies and the potential possibility of a higher frequency of side effects in patients with autoimmune thyroid diseases.

Safety Profile of Thread Lifts on the Face and Neck: An Evidence-Based Systematic Review

BACKGROUND

"Thread lifting" has quickly gained popularity as a minimally invasive treatment for facial rejuvenation. However, the effectiveness is questionable, and the safety and adverse effects are often not discussed.

OBJECTIVE

To identify and discuss the adverse effects associated with various types of threads.

MATERIALS AND METHODS

Studies describing the use of thread lifts were identified using a PubMed search. Inclusion criteria included studies in which barbed and nonbarbed threads were used for the face and neck.

RESULTS

Fifty-nine articles consisting of 14,222 patients (14,134 barbed, 81 nonbarbed, and 7 combined cases) were included. The most common side effects overall were facial asymmetry (n = 6,143), edema/tumefaction (n = 453), and ecchymosis (n = 407). Serious adverse effects were rare and consisted of paresthesias, alopecia, and injuries to vessels/glands. Most adverse effects were transient and self-resolving, with the exception of contour irregularities, injuries to vessels/glands, infections, and inflammatory reactions.

CONCLUSION

Most side effects associated with threads were self-resolving, whereas more serious cases subsided with treatment. Future studies are critical to further determine whether thread lifting provides long-lasting, safe, and satisfying results.

Efficacy and safety of thread embedding acupuncture for facial expression muscles atrophy after peripheral facial paralysis: study protocol for a randomized controlled trial

BACKGROUND

Facial expression muscles atrophy is one kind of sequelae after peripheral facial paralysis. It causes critical problems in facial appearance of patient as well as social and psychological problems. This study aims to evaluate the efficacy and safety of Thread-embedding acupuncture (TEA) for the management of facial expression muscles atrophy after peripheral facial paralysis.

METHODS

This is a patient-assessor blinded, randomized, sham-controlled trial. A total of fifty-six eligible patients will be randomly divided into TEA (n=28) and sham TEA (STEA) (n=28) groups. Both groups will receive TEA or STEA treatment at the frontal muscle and the depressor anguli oris muscle, at one predefined points once a week for eight weeks. Additionally, both groups will receive traditional acupuncture treatment at ten acupoints (GB20, LI4, LR3, GB12, ST7, SI18, LI20, BL2, SJ23, ST4) twice a week for eight weeks as a concurrent treatment. B-mode ultrasonography will be used to assess the changes in facial expression muscle thickness ratio of the affected/healthy side at baseline and at 10 weeks after screening, as the primary outcome. House-Brackmann Grade and lip mobility score will be measured and analyzed at baseline and 4, 8, 10, and 12 weeks after screening, as secondary outcomes.

DISCUSSION

The study will compare TEA with sham TEA to explore the feasibility for TEA in improving facial expression muscles atrophy after peripheral facial paralysis.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR1900027170. Registered on 3 November 2019, http://www.chictr.org.cn/edit.aspx?pid=45173&htm=4.

A Meta-Analysis and Systematic Review of the Incidences of Complications Following Facial Thread-Lifting

BACKGROUND

Facial thread-lifting (FTL) has gained more popularity, but the incidences of complications following FTL remain controversial. We aimed to perform a meta-analysis and systematic review to estimate the incidences of complications and to compare the short- and long-term satisfaction rates following FTL.

METHODS

We searched PubMed, Web of Science, Embase and Cochrane library for eligible studies. The primary outcome was the incidences of complications following FTL. The secondary outcome was the satisfaction rate immediately and 6-month after FTL. The pooled incidences of complications and 95% confidence intervals were estimated using random-effects models.

RESULTS

A total of 26 studies were included in this meta-analysis. Swelling was the most commonly reported complication with a pooled incidence of 35%, followed by skin dimpling (10%), paresthesia (6%), thread visibility/palpability (4%), infection (2%), and thread extrusion (2%). Absorbable threads were associated with a significantly lower risk of paresthesia (3.1% vs. 11.7%) and thread extrusion (1.6% vs. 7.6%) than non-absorbable threads. Patients older than 50 years had a significantly higher risk of dimpling (16% vs. 5.6%) and infection (5.9% vs. 0.7%) than their younger counterparts. In addition, the pooled long-term satisfaction rate was significantly decreased compared to it immediately after FTL (88% vs. 98%).

CONCLUSION

Non-absorbable threads and older age of patients are associated with higher risks of complications. Therefore, we recommend a judicious use of non-absorbable threads and FLT in older patients. Furthermore, it should be discussed with patients preoperatively that the rejuvenation effect of FTL may not maintain in the long-term.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Facial Thread Lifting Complications in China: Analysis and Treatment

Background:

Facial thread lifting technology has been applied for more than 30 years, with relatively few complications. In 2014, China approved polydioxanone thread (an absorbable barbed thread) for large-scale nonsurgical facial lifting. However, due to surgeons’ lack of overall experience, the complications of polydioxanone thread facelift have been relatively high.

Methods:

From April 2014 to January 2020, a total of 190 patients with postoperative complications of facelifts were treated after they underwent thread lifting in other hospitals. Of these, 189 patients were women and one was a man; the age of patients ranged from 28 to 62 years, with an average age of 37.4 years.

Results:

Patients were mainly treated in our outpatient clinic for the following complications: skin dimpling (77 cases, 40.5%); contour irregularity (32 cases, 16.8%); visible threads (31 cases, 16.3%); thread extrusion (10 cases, 5.3%); infection (17 cases, 8.9%); swelling (nine cases, 4.7%); incomplete facial paralysis (five cases, 2.6%); hyperpigmentation (four cases, 2.1%); hematoma (four cases, 2.1%); allergy (one case, 0.05%). Follow-up was scheduled 1–24 weeks after treatment.

Conclusions:

The most common complications of facial thread lifting are, in the following order, skin dimpling, contour irregularity, visible threads, and thread extrusion. The reasons for complications are mainly unfamiliarity with facial anatomy, unskilled surgical operation, and misunderstanding of the facial aesthetics of Asian women.

Revision and Secondary Facelift: Problems Frequently Encountered

Revision facelift is a very challenging operation. The goal of our study was to examine the most common problems that the facelift surgeon has to face in a revision case and to suggest ways of solving them.

Methods

A review of all patients from 2012 to 2017 in whom rhytidectomy was performed by the senior author was conducted.

Results

During the 5-year study period, the author performed 552 face lifts. After the review to confirm revision procedures, a total of 72 revision facelifts were found. On reviewing the most common problems encountered in our facelifts, we found that in addition to the stigmata of the primary facelift, which are thoroughly analyzed in our article, a new type of stigmata has been added nowadays to the revision facelift-that of the various noninvasive interventions that patients undergo after their first facelift, in their effort to postpone or avoid a second operation. In all the abovementioned cases, the surgeon has to modify his basic surgical plan accordingly, to be able to improve or solve all of those problems during the revision surgery.

Conclusions

The modern facelift surgeon often has to face much more than the stigmata of the primary facelift or the natural aging process. Thus, he/she should be appropriately trained to solve any problem we might encounter in a revision case.

Minimally Invasive Aesthetic Treatment of the Face and Neck Using Combinations of a PCL-Based Collagen Stimulator, PLLA/PLGA Suspension Sutures, and Cross-Linked Hyaluronic Acid

Background

Combinations of minimally invasive procedures (MIPs) are often used in aesthetic treatments and are increasingly considered as the new standard of care. Three agents with specific properties are available in this perspective: a polycaprolactone (PCL)-based collagen stimulator, a poly-L-lactic acid (PLLA)- and a poly-glycolic acid (PLGA)-based resorbable suspension suture with a 3D-cone technology, and a cross-linked hyaluronic acid (HA).

Objective

To develop the first practice guidelines on rejuvenation treatment of the face and the neck using combinations of these agents, whether associated or not with other widely used MIPs such as botulinum neurotoxins or energy-based devices.

Methods

A multi-disciplinary, multi-national board of plastic surgeons and dermatologists convened to develop guidelines using a predefined consensus method. The consensus was defined as ≥83% agreement rate between participants.

Results

Practice guidelines and algorithms, describing optimal procedure sequence and spacing, are proposed for the treatment of upper-, mid-, lower-face and neck, combining the PCL collagen stimulator, the PLLA/PLGA suspension sutures, and the cross-linked HA, whether associated or not with other MIPs.

Conclusion

These new guidelines provide general support to optimal management strategies. Individual treatment plans should be adapted according to the physician’s individual competence and the patient’s preferences.

Outcomes in thread lift for face, neck, and nose; A prospective chart review study with APTOS

INTRODUCTION

To evaluate the surgical efficacy and outcomes related to midface, mandible, neck (and double chin), and nose lifting with APTOS thread lift.

METHODS

In this prospective review chart study, a total of 58 patients were included (from July 2018 to July 2019). All participants underwent facial thread lifting using APTOS. The patients were followed up first week, third, and sixth month after lifting surgery. Outcomes were assessed by two surgeons and patients based on the GAIS score. All data were analyzed by SPSS-17 software with chi-square test.

RESULTS

A total of 58 patients (Mean ± SD: 52.52 ± 10.58) (F: 45, Mean ± SD:53.13 ± 11.27 years, M:13, Mean ± SD: 50.38 ± 9.43 years) were included in the study. The most common sites for the face-lifting surgery were midface and mandibular (N = 45, 77.5%), neck (N = 10, 17.3%), and nose (N = 3, 5.2%), respectively. The level of satisfaction remained unchanged (after 6 months), about 80%, for the patients, increased from 90.7% (first week) to 94.8% (sixth month) after surgery, and increased from 93.1% (first week) to 94.8% (sixth month after surgery). The highest rate of potential complications after the surgery was related to ecchymosis (17 cases, 30%), followed by complications of pain (N = 10, 17.2%), tumefaction (N = 4, 6.9%), and dimple (N = 1, 1.7%) were reported.

CONCLUSION

The results showed that satisfaction in patients and surgeons increased over time (after 6 months). Postoperative (minor) complications were also assessed and ecchymosis was found to be the most common complication. However, the proportion of postoperative complications was relatively low.

Suture Lifting: A Review of the Literature and Our Experiences

BACKGROUND

In the past 5 years, several absorbable sutures for use in minimally invasive suture lifts have appeared on the market. These newer sutures were preceded by several iterations of nonabsorbable counterparts, all of which were eventually removed from the market because of complications.

OBJECTIVE

This review will provide a history of suture lift experience, review the published evidence on the safety and efficacy of currently available absorbable suture lift materials, and detail the clinical experience of the authors using these products.

MATERIALS AND METHODS

A review of relevant clinical terms was performed on PUBMED and MEDLINE databases. All articles were reviewed, and further studies examined from citations of selected articles. Articles that focused on suture lifting using extensive dissection were excluded.

RESULTS

Twelve studies detailed the results of absorbable suture lifting largely through patient satisfaction surveys or retrospective chart review of cases. No randomized controlled studies were available.

CONCLUSION

Data on suture lifting are limited, with largely descriptive and retrospective case reports available in the literature entailed Oxford Centre evidence-based medicine Levels 2a to 5. Based on the available data, suture lifting appears to be safe and well tolerated, with patient satisfaction similar to or above that reported for other noninvasive lifting and tightening procedures. However, due to the lack of randomized controlled trials, the authors give the suture lifting Strength of Recommendation Level C. Further controlled studies are necessary to determine efficacy, longevity, and safety of this technology.

In Vitro Degradation of Polydioxanone Lifting Threads in Hyaluronic Acid

Recently, some clinicians have proposed implanting polydioxanone (PDO) threads imbibed in hyaluronic acid (HA), arguing that this may reinforce the lifting effects. However, this is controversial because PDO sutures are hydrophilic and the presence of HA could increase the rate of hydrolysis. The aim of this study was to demonstrate the degradation of PDO lifting threads in HA through ultramicroscopy. It was a qualitative research and preclinical trial. Three, 1-cm-long, segments of 23-G PDO threads were immersed in 1.5-mL non-crosslinked HA in previously labeled, sterile microcentrifuge tubes. These were observed by ultramicroscopy at 4× and 10× after 24, 48, and 72 h. Microphotographs taken after 24 h show structural changes in the fibers, presenting an increase in interlaminar spaces and dilution of violet pigmentation. At 48 h, degradation continues. PDO hygroscopy is observed as aqueous content between the peripheral layers and the central core of the thread. At 72 h, as the pigment is released, larger empty spaces are observed in the central column of the thread, and there is disorganization of the peripheral fibrils with fraying all along the fiber. HA induces rapid biodegradation of the PDO thread by hydrolysis beginning 24 h after contact of the thread with the biomaterial. The non-crosslinked HA is a powerful catalyzing agent for hydrolytic degradation of the PDO thread, because this thread is highly hydrophilic. Clinically, embedding PDO threads in HA accelerates biodegradation of the suture.