Elasticity and breaking strength of synthetic suture materials incubated in various equine physiological and pathological solutions

The Degradation of Absorbable Surgical Threads in Body Fluids: Insights from Infrared Spectroscopy Studies

This study investigates the degradation of six different types of absorbable surgical threads commonly used in clinical practice, focusing on their response to exposure to physiological fluids. The threads were subjected to hydrolytic and enzymatic degradation in physiological saline, bile, and pancreatic juice. Our findings demonstrate that bile and pancreatic juice, particularly when contaminated with bacterial strains such as Escherichia coli, Klebsiella spp., and Enterococcus faecalis, significantly accelerate the degradation process. Using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and tensile strength testing, we observed distinct differences in the chemical structure and mechanical integrity of the sutures. Principal component analysis (PCA) of the FTIR spectra revealed that PDS threads exhibited the highest resistance to degradation, maintaining their mechanical properties for a longer duration compared with Monocryl and Vicryl. These results highlight the critical role of thread selection in gastrointestinal surgeries, where prolonged exposure to bile and pancreatic juice can compromise the suture integrity and lead to postoperative complications. The insights gained from this study will contribute to improving the selection and application of absorbable threads in clinical settings.

In vitro evaluation of the effect of tris-EDTA and 0.0005% chlorhexidine solution on the strength of two absorbable sutures

OBJECTIVE

To determine the effect of 0.0005% chlorhexidine and tris-EDTA solution on the strength of three commonly used suture types for closure of equine ventral midline celiotomy.

STUDY DESIGN

Controlled laboratory study.

SAMPLE POPULATION

Knotted loops (n = 10/group, 150 knot constructs total).

METHODS

Strands of 2 polyglactin 910, 3 polyglactin 910, and 2 polydioxanone were tied to form knotted loops. All knotted loops were mounted on a tabletop force measurement machine system and loaded at 100 mm/min until the breaking force (N) was determined. The breaking force (N) of knotted loops using dry suture was recorded at study start, then of knotted loops soaked in either 0.0005% chlorhexidine and tris-EDTA for 20 min followed by incubation in equine serum (treatment) or serum alone (control) for 14 and 21 days. Analysis of variance (ANOVA) compared the breaking force between the treatment and control groups at each time point.

RESULTS

There was no significant difference in the breaking force of 2 USP polyglactin 910 (p = .35, confidence interval [CI] = -0.21-0.59), 3 USP polyglactin 910 (p = .61, CI = -0.41-0.24), or 2 USP polydioxanone (p = .76, CI = -0.63-0.46) soaked in 0.0005% chlorhexidine and tris-EDTA solution followed by equine serum when compared to each respective suture soaked in equine serum only.

CONCLUSION/CLINICAL SIGNIFICANCE

Since 0.0005% chlorhexidine and tris-EDTA solution did not exhibit a significant effect on the breaking force of the absorbable sutures studied, the solution may be used for incisional lavage in the clinical setting.

The effect of medical grade honey on tensile strength, strain, and Young's modulus of synthetic absorbable suture material used in equine surgery

BACKGROUND

Medical grade honey (MGH) has been introduced as a protective measure against surgical site infections in equine surgery, but the effect on suture material has not been investigated.

OBJECTIVE

To evaluate the effect of MGH on the tensile properties of three synthetic absorbable suture materials.

STUDY DESIGN

In vitro experiments.

METHODS

Ten strands of Polydioxanone USP 2 (PD2), Polyglactin 910 USP 2 (PG2) and Polyglecaprone USP 2-0 (PC2-0) were incubated 1, 7, 14, 21 and 28 days in MGH, phosphate-buffered saline (PBS), equine plasma (EP) and MGH mixed with equine plasma (HP). Mechanical testing was performed recording maximum load at failure (N), strain at failure and Young's modulus (N/mm2 ). The results were reported from a Welch or regular ANOVA.

RESULTS

PD2 in MGH had a significantly higher tensile strength compared to PD2 in EP (p < 0.05, mean difference (md) = 16.95 N, CI95% (9.19-24.70 N)) and PBS (p < 0.05, md = 14.48 N CI95% (6.73-22.23 N)) on day 7 and the remaining time points. PG2 incubated in MGH had a significantly higher tensile strength compared to EP (p < 0.05, md = 69.28 N CI95% (64.16-74.40 N)) and PBS (p < 0.05, md = 56.90 N CI95% (51.78-62.02 N)) until day 28. PC2-0 incubated in MGH had a significantly higher tensile strength compared to EP (p < 0.05 md = 12.40 N CI95% (4.59 N-20.20 N)) and PBS (p < 0.05 md = 11.23 CI95% (3.42-19.03 N)) on day 7 and the remaining time points.

MAIN LIMITATIONS

The sutures were unloaded during incubation and a single cycle to failure test was only performed, which does not reflect the in vivo environment where shear forces are present.

CONCLUSIONS

MGH did not negatively affect the tensile strength of the suture material and can safely be applied in contact with suture materials commonly used in equine surgery.

A preliminary investigation of the subcutaneous tissue reaction to a 3D printed polydioxanone device in horses

BACKGROUND

A 3D printed self-locking device made of polydioxanone (PDO) was developed to facilitate a standardized ligation technique. The subcutaneous tissue reaction to the device was evaluated after implantation in ten horses of mixed age, sex and breed and compared to loops of poly(lactic-co-glycolic acid) (PLGA). In two of the horses, the implants were removed before closing the skin. The appearance of the implants and surrounding tissue was followed over time using ultrasonography. Implants were removed after 10 and 27 (± 1) days for histologic examination.

RESULTS

On macroscopic inspection at day 10, the PDO-device was fragmented and the surrounding tissue was oedematous. On ultrasonographic examination, the device was seen as a hyperechoic structure with strong acoustic shadowing that could be detected 4 months post-implantation, but not at 7 months. Histology revealed a transient granulomatous inflammation, i.e., a foreign body reaction, which surrounded both PDO and PLGA implants. The type and intensity of the inflammation varied between individuals and tissue category.

CONCLUSIONS

The 3D printed PDO-device caused a transient inflammatory reaction in the subcutaneous tissue and complete resorption occurred between 4 and 7 months. Considering the intended use as a ligation device the early fragmentation warrants further adjustments of both material and the 3D printing process before the device can be used in a clinical setting.

An Evaluation of the Tensile Strength of Polyglactin Sutures After Immersion in Different Herbal Mouthwashes: An In Vitro Study

Background The process of suturing is essential to the healing of surgical wounds. Sutures on surgical wounds from fabric approximate ligament tissues, control haemorrhage, and assist the primary healing process in oral surgical procedures. The oral environment may cause the suture to lose its tensile strength, which causes tissue to open and spread infection. Different mouthwashes are recommended for effective oral hygiene maintenance postoperatively. Ideally, the use of mouthwashes should not alter the mechanical properties of suture materials. A suture material's tensile strength or ability to endure tension during knotting and long-term wound protection is measured. Aim The aim of the current study is to assess the tensile strength of polyglactin sutures following immersion in herbal mouthwashes. Methods Two commercially available synthetic braided polyglactin 910 absorbable sutures (Vicryl and Seamcryl) were chosen to assess their tensile strength following immersion in two kinds of herbal mouthwashes: nilavembu (Andrographis paniculata) silver nanoparticle mouthwash and clove-uni stevia mouthwash. The tensile strength of the sutures was evaluated using an ElectroPuls® E3000 (Instron, Norwood, MA, USA) universal testing machine. The data were transferred to IBM Statistical Package for Social Sciences (SPSS) software version 23.0 (IBM Corp., Armonk, NY, USA), wherein the tensile strength values of Vicryl and Seamcryl after immersion in two different mouthwashes compared with control were statistically analysed using a one-way analysis of variance (ANOVA) test. Results The tensile strength of Vicryl suture material was found to be higher in the clove-uni stevia mouthwash group than in the nilavembu silver nanoparticle mouthwash and control (p-value=0.000, which is statistically significant). The tensile strength of Seamcryl suture material was found to be higher in the clove-uni stevia mouthwash group than in the nilavembu silver nanoparticles mouthwash and control (p-value=0.001, which is statistically significant). Conclusion Nilavembu silver nanoparticle mouthwashes analysed in the present study decreased the tensile strength property of Vicryl suture material after immersion for 24 hours, whereas clove-uni stevia mouthwash was shown to increase the tensile strength of both Vicryl and Seamcryl suture materials. Therefore, the selection of suture material and the postoperative prescription of mouthwash should be considered for a better clinical outcome.

Effect of Common Mouthwashes on Mechanical Properties of Suture Materials Used in Dental Surgeries: A Laboratory Experiment

Background: Sutures play a pivotal role in promoting healing in any surgical procedure. However, the versatile nature of the oral environment entails additional properties in the suture materials to assure uneventful healing. A surgeon needs to understand these delicate intricacies in the immediate postoperative phase and needs some kind of algorithm in the selection of sutures that suits the different surgical scenarios. Therefore, a study was designed to observe the effect of four different types of mouthwash, viz. Avohex, Aloedent, Parodontax and Betadine, on the mechanical properties of Vicryl (polyglactin 910), PTFE (polytetrafluoroethylene), Prolene (polypropylene) and Mersilk. Methods: A total of 288 suture samples were divided in four equal groups (72 = each group) and used for the experiments. Tensile load, tensile strength as well as percentage elongation of the suture materials were evaluated in the various stated media at 3rd, 7th, 10th and 14th days, which were compared with the controls. The results were analyzed statistically and inferences were drawn. Results: Mersilk in (Avohex, Parodontax and Betadine) solutions showed a statistically significant decrease in tensile load over time. All the sutures had the highest tensile strength in Parodontax and had the lowest in Betadine solution. Vicryl and PTFE presented significant percentage elongation over time as compared to Prolene and Mersilk. Conclusion: The author has given certain recommendations but also states that there is no standard rule for the use of a particular suture material in all clinical situations. However, the selection of the suture material should be based on the type of surgery and preferences of the surgeon.

Which Suture to Choose in Hepato-Pancreatic-Biliary Surgery? Assessment of the Influence of Pancreatic Juice and Bile on the Resistance of Suturing Materials—In Vitro Research

(1) Background: The choice of appropriate surgical suture during operation is of great significance. Currently, there are no objective studies regarding the resistance of commonly used sutures in biliary tract surgery. (2) Methods: This fact leads one to conduct research concerning the resistance of the sutures (Polydioxanone, Poliglecaprone, Poliglactin 910, and their analogues coated with antibacterial triclosan) in the environment of sterile and contaminated bile and pancreatic juice. Tensile strength was tested at days 0, 7, 14, 21, and 28 of research. The study was performed in in vitro conditions for 28 days. (3) Results: Pancreatic juice and bile has a significant influence on the tensile strength of each suture. (4) Conclusions: The study indicated that sutures made of polydioxanone had the best qualities during the entire experiment.

In Vivo Versus In Vitro Degradation of a 3D Printed Resorbable Device for Ligation of Vascular Tissue in Horses

A resorbable 3D printed polydioxanone (PDO) device is manufactured to facilitate ligation of vascular tissue during surgery. The device must provide sufficient mechanical performance throughout the healing period. Therefore, degradation and mechanical performance of the device are investigated as a function of in vivo and in vitro aging. During aging the PDO device released cyclic and linear water-soluble products. In vivo aging resulted in higher relative number of linear oligomers in comparison to in vitro aging. A major loss of mechanical performance is observed after only 10 days in vivo and the Young's modulus (E) and tensile strength at break (σ_b ) decreased by 28% and 54%, respectively. This is in contrast to in vitro aging, where no loss of mechanical properties is observed during the same period. The in vivo aged devices exhibit clear holes in the matrices after 28 days, while apparent cracks are observed first after 140 days in vitro. These results highlight the sensitivity of the degradation process of resorbable devices with regards to the interactions of the device with the surrounding environment (tissues) and demonstrate the importance of in vivo testing as compliment to in vitro testing before clinical use of devices.

Tensile properties of synthetic, absorbable monofilament suture materials before and after incubation in phosphate-buffered saline

OBJECTIVE

To compare tensile properties of synthetic, absorbable, monofilament suture material before and after incubation in phosphate-buffered saline (PBS).

STUDY DESIGN

Two sizes (2-0 and 3-0) of Biosyn, Maxon, Monocryl, PDS II, Securocryl, and Securodox were tested.

SAMPLE POPULATION

Ten suture loops per group.

METHODS

Tensile strength, elongation, and modulus of suture loops were measured at baseline and after 7, 14, 21, or 28 days of incubation in PBS.

RESULTS

Size, suture material, and size × suture material interaction influenced maximum breaking load, maximum elongation, and modulus of elasticity. At baseline, 2-0 and 3-0 Maxon had the highest breaking loads (111.67 N and 79.71 N, respectively) for their size, and 2-0 PDSII and 3-0 Securodox had the lowest (68.71 N and 48.73 N, respectively). Maxon 2-0 and 3-0 had the greatest elongations (9.68 mm and 8.45 mm, respectively) for their size, and 2-0 Biosyn and 3-0 Securocryl had the least (7.21 mm and 6.58 mm, respectively). Biosyn 2-0 and 3-0 had the highest modulus. With incubation, Maxon (2-0), PDS II (2-0, 3-0), and Securodox (2-0, 3-0) maintained or gained strength over 4 weeks. Strengths of 2-0 and 3-0 Biosyn and 3-0 Maxon were maintained for 2 weeks, while Monocryl and Securocryl lost 20% to 44% of baseline strength within 1 week and 60% to 72% within 2 weeks. Day 7 strengths of 2-0 Biosyn and 2-0 Monocryl were greater than baseline strength of 2-0 PDS II. Strength of 3-0 Biosyn at day 14 was greater than strength of Monocryl at days 7 and 14 and greater than strength of 3-0 PDS II, 3-0 Securodox, and 3-0 Securocryl at baseline and days 7 and 14.

CONCLUSION

Suture tensile properties varied with suture size, composition, and brand. At baseline, Maxon suture had the greatest strength and elongation, and Biosyn had the greatest stiffness.

CLINICAL SIGNIFICANCE

Tensile strength retention, when reported as a percentage of original strength, provides insufficient information for comparison of suture tensile properties.

The Impact of γ-Irradiation and EtO Degassing on Tissue Remodeling of Collagen-based Hybrid Tubular Templates

Clinical implementation of novel products for tissue engineering and regenerative medicine requires a validated sterilization method. In this study, we investigated the effect of γ-irradiation and EtO degassing on material characteristics in vitro and the effect on template remodeling of hybrid tubular constructs in a large animal model. Hybrid tubular templates were prepared from type I collagen and Vicryl polymers and sterilized by 25 kGray of γ-irradiation or EtO degassing. The in vitro characteristics were extensively studied, including tensile strength analysis and degradation studies. For in vivo evaluation, constructs were subcutaneously implanted in goats for 1 month to form vascularized neo-tissue. Macroscopic and microscopic appearances of the γ- and EtO-sterilized constructs slightly differed due to additional processing required for the COL-Vicryl-EtO constructs. Regardless of the sterilization method, incubation in urine resulted in fast degradation of the Vicryl polymer and decreased strength (<7 days). Incubation in SBF was less invasive, and strength was maintained for at least 14 days. The difference between the two sterilization methods was otherwise limited. In contrast, subcutaneous implantation showed that the effect of sterilization was considerable. A well-vascularized tube was formed in both cases, but the γ-irradiated construct showed an organized architecture of vasculature and was mechanically more comparable to the native ureter. Moreover, the γ-irradiated construct showed advanced tissue remodeling as shown by enhanced ECM production. This study shows that the effect of sterilization on tissue remodeling cannot be predicted by in vitro analyses alone. Thus, validated sterilization methods should be incorporated early in the development of tissue engineered products, and this requires both in vitro and in vivo analyses.

Techniques for the Management of Failed Surgery for Fractures of the Neck of Femur

Background:

The majority of modern surgical treatments for managing hip fracture in the elderly are successful and result in a very low rate of revision surgery. Subsequent operations are however occasionally necessary. Optimal management of complications such as infection, dislocation or failed fixation is critical in ensuring that this frail patient group is able to survive their treatment and return to near normal function.

Methods:

This paper is a discussion of techniques, tips and tricks from a high volume hip fracture unit

Conclusion:

This article is a technique-based guide to approaching the surgical management of failed hip fracture treatment and includes sections on revising both failed fixation and failed arthroplasty.

Knot Security of 5 Metric (USP 2) Sutures: Influence of Knotting Technique, Suture Material, and Incubation Time for 14 and 28 Days in Phosphate Buffered Saline and Inflamed Equine Peritoneal Fluid

OBJECTIVES

To evaluate knot security for 3 knot types created in 3 commonly used 5 metric suture materials incubated in physiological and pathological fluids.

STUDY DESIGN

In vitro mechanical study.

SAMPLE POPULATION

Knotted suture loops (n = 5/group).

METHODS

Loops of 3 different suture materials (glycolide/lactide copolymer; polyglactin 910; polydioxanone) were created around a 20 mm rod using 3 knot types (square [SQ], surgeon's [SK], and triple knot [TK]) and were tested to failure in distraction (6 mm/min) after tying (day 0) and after being incubated for 14 and 28 days in phosphate buffered saline (PBS) or inflamed peritoneal fluid. Failure load (N) and mode were recorded and compared.

RESULTS

For polydioxanone, significant differences in force to knot failure were found between SQ and SK/TK but not between SK and TK. The force required to break all constructs increased after incubation in phosphate buffered saline (PBS). With glycolide/lactide copolymer no differences in force to knot failure were observed. With polyglactin 910, a significant difference between SQ and TK was observed, which was not seen between the other knot types. Incubation in inflamed peritoneal fluid caused a larger and more rapid decrease in force required to cause knot failure than incubation in PBS.

CONCLUSIONS

Mechanical properties of suture materials have significant effects on knot security. For polydioxanone, SQ is insufficient to create a secure knot. Additional wraps above a SK confer extra stability in some materials, but this increase may not be clinically relevant or justifiable. Glycolide/lactide copolymer had excellent knot security.