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PubMed2006

Synthesis and hydrolysis behaviour of poly(ester anhydrides) from polylactone precursors containing alkenyl moieties.

Hydroxyl-group functional polylactones were prepared and converted to acid- terminated polyesters in a reaction with a series of alkenylsuccinic anhydrides containing 8, 12, or 18 carbons in their alkenyl chains. These polyester precursors were then linked into higher molecular weight poly(ester anhydrides) containing alkenyl moieties in their polyester blocks. The hydrolysis behaviour of the poly(ester anhydrides) was found to depend on the thermal properties of the polyester precursors. For poly(ester anhydrides) prepared from low molecular weight prepolymers with thermal transitions below 37 degrees C, the presence of hydrophobic alkenyl chains in the polyester precursors slowed the rate of weight loss. Poly(ester anhydrides) prepared from higher molecular weight prepolymers showed the opposite weight-loss behaviour; i.e., the crystallinity and thermal transitions of the alkenyl chain-containing poly(ester anhydrides) were low, and the weight loss was faster than for poly(ester anhydrides) without the alkenyl chains. The differences in length of the alkenyl chain, as such, had little effect on the hydrolysis behaviour and thermal properties of the poly(ester anhydrides).

Absorption↗

PubMed2006

Thermal degradation of environmentally degradable poly(hydroxyalkanoic acid)s.

Aliphatic polyesters have attracted industrial attention as environmentally degradable thermoplastics to be used for a wide range of applications. Besides intensive studies on the biodegradability of aliphatic polyesters, understanding of the thermal stability has importance for processing, application, and recycling. The details of thermal degradation processes of five types of aliphatic polyesters; namely, poly(L-lactide), poly(3-hydroxybutyric acid), poly(4-hydroxybutyric acid), poly(delta-valerolactone), and poly(epsilon-caprolactone), were investigated by means of several thermoanalytical techniques under both isothermal and non-isothermal conditions. In this feature article, the thermal degradation behaviors of aliphatic polyesters with different numbers of carbon atoms in the main chain of the monomeric unit are reviewed. In addition, the effects of chain-end structure and residual metal compounds on the thermal degradation processes of aliphatic polyesters consisting of hydroxyalkanoic acid monomeric units are presented. Schemes of thermal degradation reaction of poly(hydroxyalkanoic acid)s.

Caproates↗

PubMedDate not supplied

Structural effects on enzymatic degradabilities for poly[(R)-3-hydroxybutyric acid] and its copolymers.

Poly[(R)-3-hydroxybutyric acid] and its copolymers were prepared by biosynthetic and chemosynthetic methods. The films of polyesters were prepared by both the solution-cast and melt-crystallized techniques. The enzymatic degradation of polyester films was carried out at 37 degrees C in an aqueous solution (pH 7.4) of PHB depolymerase from Alcaligenes faecalis. The rate of enzymatic erosion on the solution-cast films increased markedly with an increase in the fraction of second monomer units up to 10-20 mol% to reach a maximum value followed by a decrease in the erosion rate. Analysis of the water-soluble products liberated during the enzymatic degradation of polyester films showed the formation of a mixture of monomers and oligomers of (R)-3HB and hydroxyalkanoic acids units, suggesting that the active site of PHB depolymerase recognizes at least three monomeric units as substrate for the hydrolysis of ester bonds in a polymer chain. The rate of enzymatic erosion of melt-crystallized polyester films decreased with an increase in crystallinity. PHB depolymerase predominantly hydrolyzed the polymer chains in the amorphous phase and subsequently eroded crystalline phase. In addition, the enzymatic degradation of crystalline phase by PHB depolymerase progressed from the edges of crystalline lamellar stacks. The enzymatic erosion rate of crystalline phase in polyester films decreased with an increase in the lamellar thickness.

Alcaligenes↗

PubMed2001

Fatigue testing median sternotomy closures.

OBJECTIVE: Sternal dehiscence is commonly due to wire cutting through bone. With a biological model, we measured the rate of cutting through bone, of standard steel wire closure, peristernal steel wire, figure-of-eight closure, polyester and sternal bands sternotomy closure techniques. METHODS: Polyester, figure-of-eight, peristernal and sternal band closures were tested against standard closure eight times using adjacent paired samples, to eliminate biological variables. Fatigue testing was performed by a computerized materials-testing machine, cycling between loads of 1 and 10 kg. The displacements at maximum and minimum loads were measured during each cycle. Cutting through, manifested by the displacement at the maximum load between the 1st and 150th cycles was measured. The percentage cut-through of each closure method versus standard closure was calculated. RESULTS: The differences in the displacement between each of the polyester (1.01 mm), figure-of-eight (0.52 mm), peristernal (0.72 mm) and sternal band (0.66 mm) groups versus standard closure (0.22, 0.22, 2.1, 3.2 mm) in the paired samples were statistically significant (Student's paired t-test; P<0.01). There were statistically significant differences in the percentage cut-through of polyester, figure-of-eight, peristernal and sternal bands (ANOVA, P<0.001), versus standard closure. CONCLUSIONS: In our sheep sternum model, we have quantified the differing rate of cutting through bone of five types of median sternotomy closure techniques. We have controlled for bone variables by testing each closure versus standard closure using paired adjacent bone samples. Peristernal and sternal band closure techniques are significantly superior to standard closure. The use of polyester and figure-of-eight closures requires caution.

Analysis of Variance↗

PubMed2002

[Application of FTIR micro-spectroscopy in the tribology].

The wave number of characteristic absorption peak nu asC-O-C of the polyester formed on the frictional process were determined by Fourier Transform Infrared (FTIR) Micro-spectroscopy, and the wave number displacement of characteristic absorption peak nu asC-O-C was analyzed based on the conversion mass of polyester formed. The internal relations between anti-wear order rule of hydroxyl fatty acids and vibration absorption peak nu asC-O-C of polyester formed by hydroxyl fatty acids was deduced according to these results, and the anti-wear order of hydroxyl fatty acids was reasonably explained, that is 13, 14-di-hydroxydocosanoic acid > 13 (14)-monohydroxydocosanoic acid = 9,10-dihydroxyoctadecanoic acid > 9,10,12-trihydroxyoctadecanoic acid > 9(10)-monohydroxyoctadecanoic acid. A net polyester film is formed by 13, 14-dihydroxydocosanoic acid and a linear polyester film is formed by 9, (10)-monohydroxyoctadecanoic acid and 13(14)-monohydroxydocosanoic acid.

Absorption↗

PubMed1998

Long-term complications associated with prosthetic repair of incisional hernias.

OBJECTIVE: To determine whether the type of prosthetic material and technique of placement influenced long-term complications after repair of incisional hernias. DESIGN: Retrospective cohort analytic study. SETTING: University-affiliated hospital. PATIENTS: Two hundred patients undergoing open repair of abdominal incisional hernias with prosthetic material between 1985 and 1994. INTERVENTIONS: Four types of prosthetic material were used and placed either as an onlay, underlay, sandwich, or finger interdigitation technique. The materials were monofilamented polypropylene mesh (Marlex, Davol Inc, Cranston, RI), double-filamented mesh (Prolene, Ethicon Inc, Somerville, NJ), expanded polytetrafluroethylene patch (Gore-Tex, WL Gore & Associates, Phoenix, Ariz) or multifilamented polyester mesh (Mersilene, Ethicon Inc). MAIN OUTCOME MEASURES: The incidence of recurrence and complications such as enterocutaneous fistula, bowel obstruction, and infection with each type of material and technique of repair were compared with univariate and multivariate analysis. RESULTS: On univariate analysis, multifilamented polyester mesh had a significantly higher mean number of complications per patient (4.7 vs 1.4-2.3; P<.002), a higher incidence of fistula formation (16% vs 0%-2%; P<.001), a greater number of infections (16% vs 0%-6%; P<.05), and more recurrent hernias (34% vs 10%-14%; P<.05) than the other materials used. The additional mean length of stay to treat complications was also significantly longer (30 vs 3-7 days; P<.001) when polyester mesh was used. The deleterious effect of polyester mesh on long-term complications was confirmed on multiple logistic regression (P=.002). The technique of placement had no influence on outcome. CONCLUSION: Polyester mesh should no longer be used for incisional hernia repair.

Cutaneous Fistula↗

PubMed2004

Microfluidic devices obtained by thermal toner transferring on glass substrate.

A new process for the manufacture of microfluidic devices based on deposition of laser-printing toner on glass substrates is described. It is an alternative method to the toner on polyester film (toner-polyester) one, previously introduced. Commercial laser printers cannot print directly on glass, thus the toner must first be printed on a special paper and then transferred by heating under pressure to the glass surface. Although this procedure is more complex than the toner-polyester one, it can be repeated several times, yielding multiple toner layers. Even without special alignment equipment, up to four layers could be satisfactorily piled up. Characterization tests revealed that the toner-glass devices have similar behavior as toner-polyester ones regarding the toner layer porosity. The main advantages of the toner-glass technology are improved mechanical stability, possibility of multiple toner layers, augmented electroosmotic flow (EOF), and improved heat transfer. On the other hand, toner adhesion to glass is weaker than to polyester, which limits the device lifetime and usable liquid media. The measured EOF mobility (3.5 x 10(-4) cm2.V(-1).s(-1) for pH 7) suggests that it is mainly determined by the glass surface, being little influenced by the toner walls. Microchip electrophoresis with contactless conductivity detection and photometric detection were implemented using toner-glass devices.

Electrophoresis, Microchip↗

PubMed2004

Endovascular repair of paraanastomotic aneurysms after previous open aortic prosthetic reconstruction.

The aim of this study was to evaluate the effectiveness of endovascular repair of anastomotic and true aortic and iliac aneurysms occurring after prior polyester graft repair for abdominal aortic aneurysms (AAA) or aortoiliac obstructive disease. Between July 1999 and January 2003, 14 patients underwent endovascular treatment of aortic pseudoaneurysms (n = 6) or iliac aneurysms (2 patients with pseudoaneurysms and 6 patients with true aneurysms) occurring 4 to 18.4 years (mean, 8.8 years) after open aortic surgery. No patient had symptoms or positive parameters for infection of the original polyester graft. Eleven patients, including one patient with both a proximal anastomotic and a true iliac aneurysm, were treated with AneuRx (n = 8), Talent (n = 2), or Quantum LP (n = 1) bifurcated stent grafts. Three patients with an infrarenal anastomotic pseudoaneurysm were treated with a tube stent graft (Talent [n = 2] and AneuRx [n = 1]). Endovascular stent grafts were successfully inserted in all patients. Procedure-related complications or death was not seen. During a median follow-up of 12 months (range, 3-40) all anastomotic and/or true aneurysms treated with bifurcated stent grafts maintained excluded. However, two out of three patients, treated with a tube graft for proximal aneurysm exclusion, were converted. In both patients the tube stent graft did not migrate from the level of the renal arteries but fixation failed between the stent graft and the previous polyester graft, creating endotension in the thrombus of the aneurysm sac. In one of these patients the old anastomotic aneurysm ruptured 16 months after stent graft placement and the patient died 1 day after conversion because of mesenterial ischemia. At 1 year follow-up the second patient was converted successfully after enlargement of his anastomotic aneurysm due to similar disconnection between the stent graft and the polyester graft. From this experience with endovascular stent grafts, we conclude that these can be used successfully to exclude anastomotic or true aneurysms after open aortic surgery. Exclusion of aneurysms at the proximal anastomosis with tube stent grafts is apparently not durable because of the insecure distal fixation in polyester grafts. Endovascular repair with bifurcated stent grafts, however, seems to be effective at midterm follow-up.

Aged↗

PubMed1996

Growth-Associated Production of Poly(3-Hydroxyvalerate) from n-Pentanol by a Methylotrophic Bacterium, Paracoccus denitrificans.

Paracoccus denitrificans accumulated a polyester in its cells during growth on n-pentanol. The composition of the polyester varied during the cultivation: the level of the 3-hydroxyvalerate unit in the polyester increased, and eventually a homopolymeric poly(3-hydroxyvalerate) [P(3HV)] accumulated to an amount 22 to 24% of the cell dry weight. Growth-associated polyester synthesis was considerably affected by n-pentanol when its concentration was controlled at several levels. Maximum accumulation of the polyester was obtained at 0.02% (vol/vol). Physical and mechanical characteristics of the P(3HV) were determined and compared with those of other homo- and copolyesters. The P(3HV) was dextrorotatory and had number-averaged and weight-averaged molecular masses of 128,000 and 888,000 Da, respectively, with a rate of polydispersity of 6.93. The level of tensile strength of the P(3HV) was lower, and its extension to break was higher than that of the poly(3-hydroxybutyrate) homopolyester.

Journal Article↗

PubMed1994

Airway hyperresponsiveness, prevalence of chronic respiratory symptoms, and lung function in workers exposed to irritants.

The association between occupational exposure to airway irritants and the prevalence of chronic respiratory symptoms and level of lung function, and whether these associations were modified by airway hyperresponsiveness, smoking, and a history of allergy were studied in 668 workers from synthetic fibre plants. Respiratory symptoms were recorded with a self administered Dutch version of the British Medical Research Council questionnaire, with additional questions on allergy. Airway responsiveness was measured by a 30 second tidal breathing histamine challenge test. On the basis of job titles and working department, the current state of exposure of all workers was characterised as (1) no exposure, reference group; (2) white collar workers; (3) SO2 HCl, SO4(2); (4) polyester vapour; (5) oil mist and vapour; (6) polyamide and polyester vapour; (7) multiple exposure. Workers exposed to airway irritants were not simultaneously exposed to airborne dust. Airway hyperresponsiveness (AHR), defined as a 20% fall in forced expiratory volume in one second (FEV1) at < or = 32 mg/ml histamine, was present in 23% of the subjects. The association between exposure groups and prevalence of symptoms was estimated by means of multiple logistic regression; the association with level of lung function (forced vital capacity (FVC), FEV1, maximum mid-expiratory flow rate (MMEF)) was estimated by means of multiple linear regression. Both methods allow simultaneous adjustment for potential confounding factors. The exposure groups were associated with a higher prevalence of chronic respiratory symptoms. Lower prevalence of symptoms was found for workers exposed to SO2, HCl, and SO4(2-), most likely due to pre-employment selection procedures. Current smoking, AHR, and a history of allergy were significantly associated with a higher prevalence of chronic respiratory symptoms, independent of each other, and independent of irritant exposure. The association between exposure and prevalence of symptoms was greater in smokers than in ex-smokers and non-smokers. This difference was most clearly seen in the polyester vapour and polyamide and polyester vapour group. No modification of the association between exposure groups and prevalence of symptoms by airway hyperresponsiveness could be shown. The exposure groups were not significantly associated with a lower level of lung function. Adjustment for chronic respiratory symptoms did not change the results. There were no indications of a possible interaction between exposure and AHR, current smoking, or a history of allergy on lung function. Workers of the polyester vapour and the oil mist and vapour group with >10 years of exposure had a lower FEV1 (beta = -295 and -358 ml) and significantly lower MMEF (beta = -1080 and -1247 ml/s; p < 0.05) than the reference group. The number of workers of both group were, however, small (n = 10 and n = 13 respectively). More investigations between low level exposure to irritant and respiratory health.

Adult↗

PubMed2004

The effect of surface finishing and storage solutions on the color stability of resin-based composites.

BACKGROUND: The authors tested the hypothesis that surface-finishing treatments and the type of storage solutions significantly affected the staining of resin-based composites, or RBCs, and unfilled resins, or URs. METHODS: Fifty-four RBC and 54 UR disks were polymerized through a polyester film strip (Mylar, DuPont, Wilmington, Del.) and polished in one of three groups: 1-micrometer aluminum oxide, 15-microm diamond plate and no treatment (polyester film). All specimens were immersed in water for two days and then in coffee, cola or red wine for seven more days at 37 C. The authors recorded tristimulus color measurements before the immersions; after one and two days in water; and after one, two, three and seven days in the storage solutions. RESULTS: Most of the color changes occurred between day 2 in water and day 7 in the staining solution. Analysis of variance showed that the finishing treatment and storage solution significantly influenced the overall color change (deltaE), and interactions occurred between the finishing treatment and the storage solution (P < .0001) for both materials. RBC specimens generally exhibited greater color changes than did UR specimens. The polyester film finishing exhibited the greatest amount of color change, while the diamond finishing exhibited the least amount of color change. Immersion in wine caused the greatest color change for both materials; cola and coffee resulted in the smallest color change for RBC and UR specimens, respectively. CONCLUSIONS: Finishing treatments and storage solutions significantly affect the surface staining of RBC materials. Polyester film finishing and red wine produced the greatest color change after seven days for RBC specimens. CLINICAL IMPLICATIONS: Clinicians should remove the polyester film-finished surface and advise patients that drinking wine could intensify surface staining on RBC restorations.

Aluminum Oxide↗

PubMed2006

[Study of FTIR spectra and thermal analysis of polyurethane].

The thermal behavior of polyester-polyurethane and polyether-polyurethane in air atmosphere was investigated by using FTIR analysis in the temperature range from 20 to 400 degrees C. The thermal degradation behaviors of polyester-polyurethane and polyether-polyurethane in different atmospheres were investigated by using thermogravimetry analysis (TG) in the temperature range from 20 to 700 degrees C. The FTIR results together with the TG investigations showed that polyester-polyurethane has two degradation steps in air, but polyether-polyurethane has only one degradation step. The thermal analysis results also showed that the onset degradation temperature of polyether-polyurethane is lower than that of polyester-polyurethane, suggesting that the thermal stability of polyester-polyurethane is higher than polyether-polyurethane, and the onset degradation temperature of polyurethane in air is lower than that in nitrogen, suggesting that the presence of oxygen affects significantly the break of the polymeric chains.

English Abstract↗

PubMed1988

[Polymer fibers in surgery. III].

Polyester fibres were started to be used as synthetic polymer material in the mid-1950's. In comparison with polyamides they have a greater chemical and biological durability. Their elasticity, resistance to weather, abrasive strength, low susceptibility to sorption, distortion strength, no toxicity, resistance to heat treatment in sterilization, moderate capillarity, gave the polyesters their present wide usability in various fields of surgery. Polyester fibres most frequently used are: ethyl terephthalate, lawsan, dacron, terylene, elana, torlene, terytal, tetron, etc. They are used as surgical threads, knitted and weaved fabric, vascular prostheses, tendons, ligaments and bands in hernia plastic operation, in reconstruction of abdomen wall and chest and in diaphragm prosthetics. In most cases the grafts had a high mechanical and physical resistance, were biologically immune, and healed well. Polyester fibres can be modified in order to increase the durability of their anastomosis with organic tissues and to give them long gemicidal activity. The main factors which cause the fibre decomposition are the processes of hydrolysis, oxidation, and enzymatic deconstruction. In many reports knitted and gauze fabric were said to be superior to the knitted ones. It was found that by use of polyester vascular prostheses good results can be obtained in implanting them to the aorta and its branches, while in implanting into small and medium blood vessels thrombi form. On the basis of macrokinetic parameters of lavsan prostheses destruction in the organism a method for predicting the length of the exploatation properties loss of the polymer were proposed. The results were mostly convergent with the experimental ones.

Animals↗

PubMed1995

Accelerated healing of cardiovascular textiles promoted by an RGD peptide.

Polytetrafluoroethylene (PTFE) and polyethylene terephthalate (Dacron polyester) fabrics are used extensively in cardiovascular devices, e.g. heart valve sewing cuffs and vascular prostheses. While devices containing these fabrics are generally successful, it is recognized that fabrics cause complications prior to tissue ingrowth due to their thrombogenic nature. A surface active synthetic peptide, called PepTite Coating (PepTite), which was modeled after the cell attachment domain of human fibronectin has been marketed as a biocompatible coating. This peptide stimulates cell attachment through the arginine-glycine-aspartic acid (RGD) sequence. Modification of medical implants with PepTite has been shown to promote ingrowth of surrounding cells into the material leading to better tissue integration, reduced inflammation and reduced fibrotic encapsulation. In this study, polyester and PTFE textiles were modified with PepTite. The effectiveness of this coating in enhancing wound healing was investigated in a simple vascular and cardiac valve model. Our results indicate that the RGD-containing peptide, PepTite, promoted the formation of an endothelial-like cell layer on both polyester and PTFE vascular patches in the dog model. PepTite was also found to promote the formation of a significantly thinner neointima (pannus) on polyester as compared to that on its uncoated control. These results were corroborated in the cardiac valve model in which a greater amount of thin pannus and less thrombus were seen on coated polyester sewing cuffs than on control uncoated cuffs. This research shows the promising tissue response to RGD coated textiles and the potential role of this peptide in material passivation via accelerated healing.

Amino Acid Sequence↗

PubMed2004

Electrophoresis microchip fabricated by a direct-printing process with end-channel amperometric detection.

We describe the development of an electrophoresis microchip fabricated by a direct-printing process, based on lamination of printed polyester films with end-channel amperometric detection. The channel structures are defined by polyester (base and cover) and by a toner layer (walls). The polyester-toner devices presented an electroosmotic flow (EOF) magnitude of approximately 10(-5) cm2 V(-1) s(-1), which is generated by a polymeric mixture of the toner and polyester composition. The microelectrodes used for detection were produced combining this laser-printer technology to compact discs. The performance of this device was evaluated by amperometric detection of iodide and ascorbate. The detection limits found were 500 nmol.L(-1) (135 amol) and 1.8 micromol.L(-1) (486 amol) for iodide and ascorbate, respectively.

Ascorbic Acid↗

PubMed1993

Effect of different types of textile fabric on spermatogenesis: an experimental study.

The effect of different types of textile fabric on spermatogenesis was studied. Twenty-four dogs were divided into two equal groups, one of which wore cotton underpants and the other polyester ones. Seven dogs wearing nothing were used as controls. The underwear was fashioned to fit loosely in the scrotal area so as to avoid its insulating effect. It was worn continuously for 24 months during which the semen character, testicular temperature, hormones (serum testosterone, follicle stimulating hormone, luteinizing hormone, prolactin) and testicular biopsy were examined. The garment was then removed, and the same investigations repeated through another 12 months. The results were analysed statistically. In the polyester group the testicular temperature showed insignificant changes during the period when the pants were worn (P > 0.05). By the end of the 24 months there was a significant decrease in sperm count and motile sperms, with an increase in abnormal forms (P < 0.001); the testicular biopsy showed degenerative changes. After garment removal the semen character improved gradually to normal in 10 dogs; two remained oligozoospermic. There were insignificant changes (P > 0.05) in hormones during the study. In contrast, the cotton and control groups showed insignificant changes (P > 0.05) in all the aforementioned parameters during the 36 months of the study. The polyester pants thus had a deleterious effect on spermatogenesis in the dogs which was, however, reversible in the majority of cases. The cause of this effect is unknown, but it may be assumed that the electrostatic potentials generated by the polyester fabric play a role in it.

Animals↗

PubMed2000

Peritoneal adhesions to prosthetic materials: choice of mesh for incisional hernia repair.

BACKGROUND: In many cases, incisional hernia repair requires the use of prosthetic materials. The aim of this experimental study in a rat model was to assess the role of polyglactin 910 mesh and fluoropassivated polyester mesh in preventing the formation of adhesions. METHODS: In the first experiment, the formation of peritoneal adhesions was assessed after insertion of polypropylene, polypropylene combined with polyglactin 910, or no mesh. In the second experiment, adhesion formations were compared after insertion of fluoropassivated polyester, polypropylene, and no mesh. RESULTS: The first experiment showed no significant difference in adhesion formations between the polypropylene mesh and the combined mesh; however, when no mesh was used, there were significantly fewer adhesions in both experiments (p < 0.01). The second experiment showed a significantly lower degree of adhesions and a lower Adhesion Index after insertion of fluoropassivated polyester mesh than when polypropylene mesh was used (p = 0.04). CONCLUSIONS: Adding polyglactin 910 mesh to polypropylene mesh to prevent the formation of adhesions is not an effective measure. Fluoropassivated polyester meshes appear to provide a better alternative to the use of polypropylene meshes for incisional hernia repair in humans in terms of the formation of adhesions.

Animals↗

PubMed2006

Optimum location of knot for tendon surgery in side-locking loop technique.

BACKGROUND: Although various tendon repair techniques have been reported to achieve stronger repair, suture failures tend to occur near the knot. We experimentally investigated whether the location of a single core suture knot affects the biomechanical properties of the repair. METHODS: Transected bovine tendons (male Japanese black cattle, 24 months old) of the medial gastrocnemius (9-11 x 14-16 mm in diameter) were sutured with the side-locking loop technique using a USP2-sized polyethylene and polyester multifilament suture or polyester multifilament suture. The knot was made using 7 simple square ties (a surgeon's knot plus 5 ties) at three locations; on the loop, between the tendon stumps, or between the loops burying the knot in a tendon slit using a scalpel. A cyclical loading protocol from 10N to 100N was used and the loading was repeated 10,000 times. FINDINGS: The gap was most decreased and the ultimate strength was most increased when the knot was located between the loops when using a polyethylene and polyester multifilament suture. Cross-sectional area of the tendon showed the ratio of the buried knot relative to the tendon was only 1.6-2.3%, and the polyethylene and polyester multifilament suture was very durable against frictional abrasion. INTERPRETATION: We found that the knot between the loops, buried in the bovine tendon provided the optimum results.

Animals↗