Tensile testing in feline ventral abdominal coeliotomy closure with different sizes of polydioxanone suture material: a biomechanical study.

OBJECTIVES: The aim of this study was to evaluate, in vitro, the load and type of failure of the sutured ventral abdominal fascia of cats with different sizes of suture material made of polydioxanone (PDX) (2-0, 3-0, 4-0, 5-0 USP). METHODS: A total of 32 samples of the ventral abdominal wall from 16 cadaveric cats were harvested using an hourglass-shaped template. The samples were sectioned longitudinally along the linea alba and then sutured together in a continuous pattern using four different randomly assigned sizes of pdx suture material (2-0, 3-0, 4-0, 5-0 USP). A universal testing machine was used for linear distraction of the samples. The tensile strength and type of failure were recorded and analysed. Three types of failure were defined: suture material failure (S), suture line failure (T1) and failure of the abdominal wall further away from the linea alba (T2). RESULTS: The frequency of suture material failure decreased with increasing suture size. Suture size 5-0 failed due to a S failure in 6/8 samples, PDX 4-0 failed in 2/8 samples and PDX 3-0 failed in only 1/8 samples. However, PDX 2-0 failed due to only T1 or T2 failures, with both failures being almost equally represented. No statistically significant differences in the load to failure between PDX 2-0, 3-0 and 4-0 were noted (P >0.05). The risk of suture failure increased with decreasing suture size diameter. CONCLUSIONS AND RELEVANCE: PDX 2-0 and 3-0 can be used without reservation for the closure of ventral midline coeliotomy in cats. Although there was no statistically significant difference between PDX 2-0, 3-0 and 4-0, PDX 4-0 showed a higher probability for suture breakage and should be used only after careful consideration of the patient while clinical evaluation is pending. Pdx 5-0 cannot be recommended as a safe suture size for this type of surgical closure.

Postoperative monitoring of ovariohysterectomy carried out with two types of surgical sutures in shelter cats and differences in selected blood parameters between shelter and pet cats.

BACKGROUND: Reduction of inflammation and early detection of complications after surgical procedures are important objectives for proper veterinary practice. This study aimed to evaluate the differences between shelter and pet female cats in selected acute-phase parameters scheduled to ovariohysterectomy. Postoperative monitoring after ovariohysterectomy with the same laboratory parameters was performed in shelter cats, in which two different types of surgical sutures were used for the entire procedure. The experimental group comprised 40 female cats from animal shelters ('shelter cats,' n = 40). These cats were divided into two subgroups: group A (n = 20) operated on with absorbable sutures and group NA (n = 20) operated on with non-absorbable sutures. In addition, the same parameters were evaluated in pet female cats (n = 19). Blood was collected from shelter cats immediately before surgery (term 0), at 24 and 72 h (terms 1 and 3, respectively), and at 7 and 14 days (terms 7 and 14, respectively) after ovariohysterectomy. Blood samples from the pet cat group were collected only once. RESULT: The mean haptoglobin concentration before ovariohysterectomy in pet cats was significantly lower than that in shelter cats. Fibrinogen concentration was significantly lower in pet cats than in cats from group A. Serum albumin, beta-1, beta-2, and gamma-globulin concentrations were significantly higher in the shelter cats than in the pet cats. Subcutaneous tissue thickening at the site of the postoperative wound was observed in five patients cats (25%) in group A, and two (10%) cats in the NA group. CONCLUSION: These results indicate that ovariohysterectomy leads to local and general inflammatory responses. The majority of cats from animal shelters suffered from subclinical inflammation.

Biomechanical comparison of bone staple fixation methods with suture material for median sternotomy closure using 3D-printed bone models.

AIM: To compare the biomechanical properties of three different sternal closure techniques in a 3D-printed bone model of a sternum from a 30-kg dog. METHODS: Median sternotomy was performed on a total of 90 three-dimensional (3D) copies of a polycarbonate (PC) model of a sternum, generated from the CT images of the sternum of a 30-kg German Shepherd dog. Three different methods were used to repair the sternotomies: polydioxanone suture (group PDS, n = 30), stainless steel bone staples (group SS, n = 30), and nitinol bone staples (group NS, n = 30). Each repair method was tested by applying tensile force in one of three ways (longitudinally, laterally, or torsionally) resulting in a sample size of n = 10 for each repair method-loading combination. In all experiments, the loads at 1-mm and 2-mm gap formation, failure, and the displacement at the failure point were measured. RESULTS: In lateral distraction and longitudinal shear tests, NS and SS staple repairs required application of significantly greater force than PDS across all displacement criteria (1 and 2 mm). NS exhibited significantly greater failure load than PDS. In torsion tests, NS required significantly greater application of force compared to SS or PDS at all displacement criteria (1 and 2 mm) and exhibited a greater failure load than PDS. In terms of displacement at failure point, PDS suture showed more displacement than SS or NS across all experiments (laterally, longitudinally, torsionally). CONCLUSIONS: In this study, bone staples were mechanically superior to PDS suture in median sternotomy closure using 3D-printed bone model in terms of 1-mm, 2-mm displacement loads, and displacement at failure. NS had a higher failure load than PDS under lateral, longitudinal, and torsional distraction. CLINICAL RELEVANCE: These study results imply that bone staples can be considered as an alternative surgical method for median sternotomy closure in dogs.

Rectal tear repair using barbed suture in the horse.

OBJECTIVE: To describe the repair utilizing integral-anchor barbed suture in equine rectal tears. ANIMALS: 3 horses aged 3 to 10 years old with grade 3 to 4 rectal tears. CLINICAL PRESENTATION: Grade 3 and 4 rectal tears were referred for surgical repair immediately after iatrogenic tearing or tearing during parturition. Integral-anchor barbed suture (Stratafix Symmetric PDS Plus, size 1, 18" CT-1) was placed using long-handled instruments or hand closure depending on the accessibility and visibility of the tear. Closure of grade 3 tears was performed using a continuous appositional pattern. A horizontal mattress pattern was performed in the grade 4 tear. No other surgical procedures were performed. RESULTS: Two grade 3 tears were successfully repaired with no complications and discharged from the hospital. One grade 4 tear was successfully repaired; however, 4 days post-surgery partial dehiscence of the suture site occurred, and the horse was euthanized. CLINICAL RELEVANCE: Grade 3 rectal tears were repaired successfully by using an integral-anchor barbed suture. No post-operative complications were reported. Blind hand suturing could be performed in cranial locations when the laceration could not be made visible. For grade 4 rectal tears, additional surgical procedures beyond barbed suture closure are needed.

Evaluation of the in vitro performance of the double forwarder knot, compared to square and surgeon's knots using large gauge suture.

OBJECTIVE: The aim of the study was to evaluate the strength and size of the double forwarder (DF) knot in 2 and 3 USP polyglactin 910 when used to form a ligature and to compare the knot holding capacity (KHC), size and weight of the DF knot to surgeon's (SU) and square (SQ) knots with varying numbers of throws. STUDY DESIGN: Laboratory study. STUDY POPULATION: Knotted suture. METHODS: Knots were tied using 2 and 3 USP polyglactin 910 and tested on a universal testing machine under linear tension. Mode of failure and (KHC) were recorded. Knot volume and weight were determined by digital micrometer and balance. KHC, size, and weight between knot type, number of throws, and suture type and size were compared using ANOVA testing, with p < .05 as significant. RESULTS: In both suture types, DF knots had a higher KHC than SQ/SU knots (p < .004), with the exception of SU knots with 6-8 throws in 3 USP polyglactin 910 (p > .42). All DF knots failed by suture breakage at the knot, as did all SQ/SU knots with >6 throws. DF knots in 2 and 3 USP polyglactin 910 were larger and heavier than SQ and SU knots when the same number of throws was applied (p < .003). CONCLUSION: Self-locking DF knots provided increased strength compared to SU/SQ in large gauge suture but only when fewer than six throws are applied to SU/SQ knots. CLINICAL RELEVANCE: The new DF knot could be an alternative for a secure ligature.

Comparison of incisional bursting strength of a bidirectional absorbable knotless suture material versus a standard continuous absorbable suture material for closure of the equine linea alba.

OBJECTIVE: To evaluate the use of bidirectional knotless barbed suture material for closure of the equine linea alba. STUDY DESIGN: Laboratory study. ANIMAL OR SAMPLE POPULATION: Adult light horse cadavers (n = 24). METHODS: A 25 cm incision was made through the linea alba, and a 200 L polyurethane bladder was positioned within the abdomen. The linea alba was closed either using USP2/EP5 bidirectional polydioxanone barbed suture or USP2/EP5 standard polydioxanone suture in a simple continuous pattern. Closure time was recorded for each suture type. The bladder was air-insufflated at 40 L/min, and the pressure at body wall failure recorded. The length of suture used for wound closure and wound failure modes were recorded. Suture length, closure time, bursting pressure, and failure modes were compared using Welch-Aspin t-tests. RESULTS: The incisional bursting pressure was comparable between the two groups (p > .05). Less suture material (p < .01) was required with the barbed suture than the standard suture. Closure time was less for the barbed suture than the standard suture (p < .01). Suture failure was the main failure mode in both groups (83% cases). CONCLUSIONS: Closure of the equine linea alba using bidirectional barbed suture material reduced the amount of foreign material in the wound and decreased closure time without compromising incisional strength. CLINICAL RELEVANCE: Bidirectional barbed suture material could be considered as an alternative to standard suture materials for closure of the equine line alba.

Biomechanical comparison of canine median sternotomy closure using suture tape and orthopedic wire cerclage.

OBJECTIVE: To compare the mechanical properties of suture tape and orthopedic wire cerclage in an ex vivo canine median sternotomy model. STUDY DESIGN: Ex vivo. ANIMALS: Twelve large-breed canine cadaveric sternums. METHODS: Median sternotomies were performed, leaving the manubrium intact. The specimens were randomly assigned to group W (20-gauge stainless steel orthopedic wire cerclage in a figure-of-eight pattern) or group ST (suture tape in a figure-of-eight pattern). Each specimen was laterally distracted until failure using an electrodynamic materials-testing system. RESULTS: No differences were observed for displacement, yield load, maximum load, implant failure between the groups. The orthopedic wire construct was stiffer than the suture tape construct. CONCLUSION: Suture tape was biomechanically similar to orthopedic wire cerclage for sternotomy closure in dogs, although wire constructs were stiffer. CLINICAL SIGNIFICANCE: Suture tape may represent an alternative to cerclage wire for sternotomy closure in dogs. Additional studies evaluating its clinical use are needed.

Biomechanical evaluation of three adjunctive methods of orthopedic tension band-wire fixation to augment simulated patella tendon repairs in dogs.

OBJECTIVE: To evaluate the effects of three adjunctive methods of tension band wire fixation (TBWF) on the biomechanical properties, gap formation, and failure mode in simulated canine patella tendon rupture (RPT). STUDY DESIGN: Randomized, ex vivo. SAMPLE POPULATION: Paired hindlimbs from 32 dog cadavers. METHODS: Patellar tendons (PTs) and associated bone-muscle-tendon units were harvested. Each PT was transected then sutured using a core locking loop and simple continuous epitendinous pattern. Each hindlimb was randomly assigned to one of three groups (n = 18 hindlimbs/group) using 18 gauge 316 L wire, anchored to the tibial crest distally, to perform transpatellar, suprapatellar, or combined tension band-wire (TBW) augmentation. Ten hindlimbs were utilized as control specimens. Yield, peak, and failure loads, stiffness, loads to 1 and 3 mm gap formation, and failure mode were evaluated. RESULTS: Combined transpatellar and suprapatellar TBW augmentation was superior to transpatellar or suprapatellar groups alone. Yield (p = .0008), peak (p = .004), and failure loads (p = .005) were greater for the combined group than for the transpatellar (p = .048) and suprapatellar groups (p = .01) respectively. There was no difference regarding the occurrence of 1 or 3 mm gap formation (1 mm, p = .05; 3 mm, p = .06); however, loads required to cause gap formation were greater in the combined group (p = .036). Mode of failure differed between techniques used for PT augmentation (p < .001). CONCLUSION: Combined transpatellar and suprapatellar adjunctive TBW augmentation for simulated PT repairs was biomechanically superior to either transpatellar or suprapatellar TBWF alone. CLINICAL SIGNIFICANCE: Combined suprapatellar and transpatellar TBWF may offer a viable surgical option for increased repair-site strength and greater loads to gap formation. Further studies investigating alternative techniques and materials for RPT repair augmentation are warranted.

Influence of three different closure techniques on leakage pressures and leakage location following partial cystectomies in normal dogs.

BACKGROUND: Transitional cell carcinoma (TCC) is the most common neoplasia affecting the canine urinary bladder. Partial cystectomy, when used adjuctively with medical management, has been shown to meaningfully extend medial survival time. Surgical stapling devices have a wide variety of uses and advantages over traditional closure methods and, to date, investigation into their use in canine partial cystectomies has not been documented. OBJECTIVE: To determine the influence of three closure techniques on ex vivo leakage pressures and leakage location following canine partial cystectomy. METHODS: Specimens were assigned to one of three closure techniques: simple continuous appositional closure with 3-0 suture, closure with a 60 mm gastrointestinal stapler with a 3.5 mm cartridge, and placement of a Cushing suture to augment the stapled closure, with each group containing 12 specimens. Mean initial leakage pressure (ILP), maximum leakage pressure (MLP), and leakage location at the time that ILP was recorded were compared between groups. RESULTS: Oversewn stapled constructs leaked at significantly higher ILP (28.5 mmHg) than those in the sutured (17 mmHg) or stapled (22.8 mmHg) group, respectively. MLP was greater in the oversewn stapled construct group compared to other groups. Leakage was detected in 97% partial cystectomies, with leakage occurring from the needle holes in 100% of the sutured closure group, from the staple holes in 100% of the stapled only group, and from the incisional line in 83% and from bladder wall rupture in 8% of the augmented staple closure group. All closure methods withstood normal physiologic cystic pressures. CONCLUSIONS: Placement of a Cushing suture to augment stapled closures improved the ability of partial cystectomies to sustain higher intravesicular pressures compared with sutured or stapled bladder closures alone. Further in vivo studies are required to determine the clinical significance of these findings and the role of stapling equipment for partial cystectomy, as well as the clinical significance of suture penetration through the urinary bladder mucosa during closure.

Prospective, randomized, double blind comparison of suture materials with and without triclosan in dogs undergoing tibial plateau leveling osteotomy.

Objectives: To determine if triclosan-impregnated suture decreases surgical site infection rates after tibial plateau leveling osteotomy (TPLO) in dogs. Sample population: There were 116 dogs with naturally occurring cranial cruciate ligament disease presenting for treatment with TPLO. Procedures: Written consent was obtained by all clients in order to be included in this study. Dogs were randomly assigned a suture type immediately before the start of anesthesia. Infection rates were compared between the suture groups, as were the gender, duration of anesthesia, duration of surgery, age of dog, weight, length of incision, and stifle side. Direct examination by a veterinarian was conducted at 24 h, 10 to 14 d, and 8 to 12 wk after surgery. If the dogs did not return for direct examination, owners were contacted by a veterinarian and phone interviews were conducted. Results: Overall, 12.9% of the incisions were diagnosed with a surgical site infection (SSI). The SSI rate for dogs that received the triclosan suture was 5.35% (3/56), and the rate for dogs that received the regular suture was 19.64% (11/56), with P = 0.016. The duration of anesthesia, duration of surgery, age, weight, length of incision, and right versus left stifle did not show a significant difference in infection rates. The suture type did have a significant effect, and triclosan-impregnated suture had a decreased infection rate when compared to regular suture. Gender also had a significant effect, with P = 0.032. Conclusion: Triclosan-impregnated suture decreased SSI when used for closure in dogs undergoing TPLO. Triclosan-impregnated suture may be considered a material of choice to close surgical wounds at risk of SSI when implants are used.

Comparaison prospective, randomisée, en double aveugle des matériaux de suture avec et sans triclosan chez les chiens subissant une ostéotomie de nivellement du plateau tibial. Objectifs: Déterminer si la suture imprégnée de triclosan diminue les taux d'infection du site opératoire après une ostéotomie de nivellement du plateau tibial (TPLO) chez le chien. Échantillon de population: Il y avait 116 chiens avec une pathologie naturelle du ligament croisé crânial se présentant pour un traitement avec TPLO. Procédures: Un consentement écrit a été obtenu par tous les clients afin d'être inclus dans cette étude. Les chiens ont été répartis au hasard à un type de suture immédiatement avant le début de l'anesthésie. Les taux d'infection ont été comparés entre les groupes de suture, de même que le sexe, la durée de l'anesthésie, la durée de la chirurgie, l'âge du chien, le poids, la longueur de l'incision et le côté du grasset. Un examen direct par un vétérinaire a été effectué à 24 h, 10 à 14 j et 8 à 12 semaines après la chirurgie. Si les chiens ne revenaient pas pour un examen direct, les propriétaires étaient contactés par un vétérinaire et des entretiens téléphoniques étaient menés. Résultats: Dans l'ensemble, 12,9 % des incisions ont été diagnostiquées avec une infection du site opératoire (SSI). Le taux de SSI pour les chiens ayant reçu la suture au triclosan était de 5,35 % (3/56) et le taux pour les chiens ayant reçu la suture régulière était de 19,64 % (11/56), avec P = 0,016. La durée de l'anesthésie, la durée de la chirurgie, l'âge, le poids, la longueur de l'incision et le grasset droit versus le gauche n'ont pas montré de différence significative dans les taux d'infection. Le type de suture avait un effet significatif et la suture imprégnée de triclosan avait un taux d'infection réduit par rapport à la suture ordinaire. Le sexe avait également un effet significatif, avec P = 0,032. Conclusion: La suture imprégnée de triclosan a diminué le SSI lorsqu'elle était utilisée pour la fermeture de l'incision chez les chiens subissant une TPLO. La suture imprégnée de triclosan peut être considérée comme un matériau de choix pour fermer les plaies chirurgicales à risque de SSI lorsque des implants sont utilisés.(Traduit par Dr Serge Messier).

Clinical outcomes of the use of unidirectional barbed sutures in gastrointestinal surgery for dogs and cats: A retrospective study.

OBJECTIVE: To report the clinical outcomes of gastrointestinal surgery using unidirectional barbed sutures in single-layer appositional closure in dogs and cats. STUDY DESIGN: Retrospective and descriptive study. SAMPLE POPULATION: Twenty-six client-owned dogs; three client-owned cats. METHODS: Medical records of dogs and cats that received gastrointestinal surgery closed with unidirectional barbed sutures were reviewed to collect information on signalment, physical examinations, diagnostics, surgical procedures, and complications. Short- and long-term follow-up information was collected from the medical records, the owners, or the referring veterinarians. RESULTS: Six gastrotomies, 21 enterotomies, and nine enterectomies were closed with a simple continuous pattern with unidirectional barbed glycomer 631 sutures. Nine dogs had multiple surgical sites closed with unidirectional barbed sutures. None of the cases in the study developed leakage, dehiscence, or septic peritonitis during the 14-day short-term follow up. Long-term follow up information was collected for 19 patients. The median long-term follow-up time was 1076 days (range: 20-2179 days). Two dogs had intestinal obstruction due to strictures at the surgical site 20 and 27 days after surgery. Both were resolved with an enterectomy of the original surgical site. CONCLUSION: Unidirectional barbed suture was not associated with a risk of leakage or dehiscence after gastrointestinal surgery in dogs and cats. However, strictures may develop in the long term. CLINICAL SIGNIFICANCE: Unidirectional barbed sutures can be used during gastrointestinal surgery in client-owned dogs and cats. Further investigation of the role of unidirectional barbed sutures leading to abscess, fibrosis, or stricture is necessary.

Ex-vivo biomechanical analysis of an original repair of canine calcaneal tendon rupture using a synthetic implant as mechanical support fixed by sutures in the proximal tendinous part and by an interference screw in the bone distal part.

Background: Rupture of the common calcaneal tendon is the second most frequent tendon rupture in dogs and may lead to severe lameness and pain. Surgical repair consists of re-apposition of the damaged tendon ends using sutures, but this type of repair is not always possible especially if the tendon has retracted. Tendon augmentation with an ultra-high molecular weight polyethylene (UHMWPE) implant is a recent solution to support the sutures and allow the repair of the canine calcaneal tendon. However, its biomechanical fixation strength remains untested for this pathology. Aim: To evaluate the biomechanical fixation strength of a UHMWPE implant for the repair of the canine calcaneal tendon. Methods: Ex-vivo biomechanical study was carried out on eight cadaveric hindlimbs from four adult dogs. Hindlimbs were tested under two independent modalities: proximal tendinous fixation (PTF) and distal calcaneus fixation (DCF), using a testing machine. PTF was achieved by eight simple interrupted polypropylene sutures performed through the UHMWPE implant. The latter was sandwiched inside the gastrocnemius tendon, which had previously been incised over about 5 cm longitudinally, and through the tendon of the superficial digital flexor. DCF was performed using an interference screw, which locked the UHMWPE implant into a calcaneus tunnel drilled perpendicularly. Results: Yield, failure load, and linear stiffness (mean ± SD) for the DCF modality were 920 ± 139 N, 1,007 ± 146 N, and 92 ± 15.21, respectively, which were greater than for the PTF modality (663 ± 92 N, 685 ± 84 N and 25.71 ± 5.74, respectively, p < 0.05). Failure modes were different between fixation modalities: for PTF it was suture breakage (n = 7/8), while for DCF it was implant damage and slippage (n = 8/8). Conclusion: The biomechanical fixation strength of the UHMWPE implant was greater for DCF than that of PTF, and should be suitable for calcaneal tendon repair in dogs. The clinical prediction of rupture of this calcaneal tendon repair will occur at the level of the PTF.

Axial twisting within an ending loop of a continuous suture pattern affects the biomechanical properties of knots of certain suture sizes and types.

OBJECTIVE: To determine whether axial twisting within an ending loop negatively impacts maximum load to failure and failure mode of suture knots. SAMPLES: 525 knots (15 samples each of 7 different suture types/sizes tested in 5 knot-twist configurations each). PROCEDURES: Each suture type (polydioxanone [PDO], Monoderm [polyglecaprone 25], and Nylon) and size (1, 0, 2-0, 3-0) were used to create a starting square knot, and each of the following ending square knot configurations: 0 twists, 1 twist, 4 twists, and 10 twists. Each suture was tested for failure using a universal testing machine (Instron, Instron Corp) with a 100 kg load cell at a speed of 100 mm/min. Each suture and knot was evaluated for a mode of failure using gross evaluation of the knots and video footage recorded during testing. Maximum load at failure (P-value set at .005) and failure mode (p-value set at 0.003) were recorded for each group. RESULTS: Maximum load at failure was decreased in knots tied within ending loops containing more twists for some types and sizes of the suture. With 4 twists, 0-PDO, 1 PDO, and 2-0 Nylon was more likely to fail at the knot than knots with 0 twists. All sutures containing 10 twists, except 3-0 Monoderm, were more likely to fail at the knot than knots with 0 twists. CLINICAL RELEVANCE: The number of twists within the ending loop may not increase the risk of failure at the knot; however, it can decrease the maximum load to failure at a knot, particularly as the suture size increases.

Comparison of incisional gastropexy with and without addition of two full-thickness stomach to body wall sutures.

OBJECTIVE: To compare complications between a modified incisional gastropexy (MIG) technique and standard incisional gastropexy (SIG). ANIMALS: 347 client-owned dogs. PROCEDURES: Dogs that had undergone SIG or MIG from March 2005 through April 2019 were identified through a medical record search of the University of Missouri Veterinary Health Center. The MIG technique is identical to SIG except 2 additional simple interrupted sutures are added, 1 cranial and 1 caudal to the continuous suture line, going full thickness into the stomach to ensure engagement of submucosa. Medical record information was used to identify intraoperative, postoperative, and short-term complications, and telephone or email communication to pet owners and/or referring veterinarians was used to identify complications (short-term and long-term) after discontinuance of care at the University of Missouri Veterinary Health Center. Intraoperative, postoperative, short-term, and long-term complications were analyzed in aggregate within 6 matched groupings: (1) gastropexy for gastric dilatation-volvulus, (2) prophylactic gastropexy without other procedures, (3) gastropexy with ovariohysterectomy, (4) gastropexy with castration, (5) gastropexy with splenectomy, and (6) gastropexy with celiotomy other than splenectomy. Overall rates of complications potentially attributed to gastropexy were compared between SIG and MIG using the Fisher exact test. Overall rates of complications not attributed to gastropexy were compared between SIG and MIG using the χ2 test. RESULTS: There were no significant differences in overall complication rates between SIG and MIG. CLINICAL RELEVANCE: Surgeons who feel that engagement of gastric submucosa is important for gastropexy success may use the MIG technique with minimal fear of complications. However, superiority of one technique over the other cannot be determined on the basis of this study.

Addition of two full-thickness simple interrupted sutures to standard incisional gastropexy increases gastropexy biomechanical strength.

OBJECTIVE: To compare the acute strength (failure load and work to failure) of standard incisional gastropexy (SIG) and modified incisional gastropexy (MIG). ANIMALS: 37 pig cadavers. PROCEDURES: Stomachs and right abdominal walls were harvested from pigs euthanized for reasons unrelated to this study. The tissues were stored in lactated Ringer's solution overnight in a 5 °C cooler. Matching body wall and stomach tissue pairs were randomized and divided into 2 groups, on which either SIG or MIG was performed the following day. The MIG technique was identical to SIG except 2 additional simple interrupted sutures, 1 cranial and 1 caudal to the continuous suture line, were placed full thickness into the stomach to ensure engagement of the submucosa. After gastropexy, the samples underwent biomechanical testing. Information regarding change in position and load was generated by the MTESTQuattro software. Mode of failure was examined after the procedure was complete. RESULTS: The MIG had higher failure load and work to failure compared to SIG. All failures were caused by gastric tissue tearing. CLINICAL RELEVANCE: The MIG is biomechanically superior to SIG and may provide more security than SIG during healing. However, clinical study is needed to ascertain if there is a difference in gastropexy failure and complications between these 2 techniques.

A biomechanical comparison of a novel two-loop suture technique and two sutures for laryngoplasty in the horse.

OBJECTIVES: Evaluation of the strength of the novel suture technique by comparison with a 2-interrupted suture technique. SAMPLE: 40 equine larynges. PROCEDURES: 40 larynges were used; 16 laryngoplasties were performed using the currently accepted 2-suture technique and 16 using the novel suture technique. These specimens were subjected to a single cycle to failure. Eight specimens were used to compare the rima glottidis area achieved with 2 different techniques. RESULTS: The mean force to failure, as well as the rima glottidis area of both constructs, were not significantly different. The cricoid width did not have a significant effect on the force to failure. CLINICAL RELEVANCE: Our results suggest that both constructs are equally strong and can achieve a similar cross-sectional area of the rima glottidis. Laryngoplasty ("tie-back") is currently the treatment of choice for horses with exercise intolerance due to recurrent laryngeal neuropathy. Failure to maintain the expected degree of arytenoid abduction post-surgery occurs in some horses. We believe this novel 2-loop pulley load-sharing suture technique can help achieve and, more importantly, maintain the desired degree of abduction during surgery.

Influence of conventional versus unidirectional barbed suture on leakage pressures in canine vesicourethral anastomosis: An ex-vivo study.

OBJECTIVE: To compare leakage pressures of vesicourethral anastomosis (VUA) performed with conventional and unidirectional barbed sutures in canine cadaveric tissue. STUDY DESIGN: Experimental, ex-vivo, randomized study. ANIMALS: A total of 24 male canine bladders with the urethra. METHODS: Specimens after prostatectomy were randomly divided into a unidirectional barbed suture (UBS) or a conventional suture (C) group. For the UBS group, the VUA was performed with 4-0 unidirectional barbed sutures. For the C group, the VUA was performed with 4-0 monofilament absorbable suture. The VUA was completed with two simple continuous sutures. Surgical time, leakage pressure, site of leakage, and the number of suture bites were recorded. RESULTS: The median suturing time was 12.70 minutes (range: 7.50-16.10 min) for the UBS group and 17.30 minutes (range: 14.00-21.30 min) for the C group (p < .0002). The median leakage pressure was 8.60 mmHg (range: 5.00-17.20 mmHg) for the UBS group and 11.70 mmHg (range: 6.00-18.50 mmHg) for the C group (p = .236). The median number of suture bites was 14 (range:11-27) for the UBS group and 19 (range:17-28) for the C group (p = .012). CONCLUSION: Unidirectional barbed suture does not statistically affect the acute leakage pressure of VUA in normal cadaveric specimen. It resulted in a shorter surgical time and fewer suture bite placements. CLINICAL SIGNIFICANCE: A urinary catheter will still be required when a unidirectional barbed suture is used to complete a VUA in dogs to prevent extravasation of urine in the postoperative period.

Tensile strength and knot security of five suture materials exposed to natural summer conditions of a temperate lake.

OBJECTIVE: Wild fish and other aquatic ectotherms are often subjected to procedures during field research that require wound closure using sutures. A variety of absorbable sutures are available for such purposes, yet degradation processes are highly dependent on temperature, and the environments in which wild ectotherms are released are almost always colder than the conditions for which absorbable sutures are typically designed (i.e., ~37°C). We therefore studied the degradation of various suture materials under a set of biologically relevant conditions for temperate freshwater fish. METHODS: Using a force gauge, we tested the tensile strengths and knot securities of loops tied with five different absorbable suture materials (PDS-II, dyed coated Vicryl, undyed coated Vicryl, plain gut, and chromic gut) prior to and during submersion in a temperate lake over an 8-week period. RESULT: The naturally derived collagen-based suture materials (i.e., plain gut and chromic gut) exhibited major decreases in tensile strength within 2 weeks of submersion but maintained relatively high knot security throughout the study period. The synthetic suture loops had poorer initial knot securities that increased following submersion and showed little to no evidence of degradation after 8 weeks. CONCLUSION: Variable rates of absorbable suture degradation, or lack thereof, were observed. We discuss the implications of these trends for fish welfare considerations such as suture retention, wound healing, inflammation, and infection under natural conditions.

The effect of cyanoacrylate on knot elongation in three sutures used for prosthetic laryngoplasty in the horse.

OBJECTIVE: This study investigated the elongation following cyclic loading on square knots of 5 USP multifilament long-chain ultra-high molecular weight polyethylene core (UHMWPE), 2 mm woven UHMWPE tape, and 5 USP braided polyester, with and without cyanoacrylate glue. STUDY DESIGN: Experimental study. SAMPLE POPULATION: n = 4. METHODS: Three conditions (suture without knot, suture with knot, suture with knot + cyanoacrylate) were evaluated for each suture material on a mechanical test stand by measuring the increased length of the construct after cycling from 25 to 50N for 1000 repetitions at 20 mm/second. Knot elongation was determined by subtracting the length of the control suture from the suture with knot or suture with knot + cyanoacrylate. The data were analyzed with a linear regression model with robust estimation of variance. Post-hoc analysis determined the model adjusted differences (square knot vs. cyanoacrylate) as a difference from control. t-tests were conducted to identify the significant findings. RESULTS: Total elongation of polyester (6.2-7.8 mm) was greater than multifilament UHMWPE (3.4-6.4 mm) and UHMWPE tape (2-3.7 mm) for all conditions. Polyester had the lowest knot elongation (1.6 mm) and the addition of cyanoacrylate decreased knot elongation for polyester by 1 mm. CONCLUSIONS: Polyester had the most total construct elongation followed by multifilament UHMWPE and UHMWPE tape. Polyester showed the least knot elongation and cyanoacrylate decreased this knot elongation. CLINICAL SIGNIFICANCE: Total construct and knot elongation should be considered as contributing factors to loss of arytenoid abduction following prosthetic laryngoplasty when using polyester, multifilament UHMWPE, or UHMWPE tape. Addition of cyanoacrylate to polyester knots should be explored to limit elongation.

Tissue sealing versus suture ligation in open canine ovariectomy: Surgical times, intraoperative nociceptive response and frequency of complications.

BACKGROUND: In this study, we compared two different techniques currently used for open canine ovariectomy: traditional method utilising absorbable suture and vessel sealing device (ENSEAL® Ethicon Endo-Surgery, Cincinnati, OH). OBJECTIVES: The aim of this study was to compare the surgical times, intraoperative nociceptive response and the frequency of intraoperative complications in the canine ovariectomy procedure using these two techniques. METHODS: Forty bitches were randomly divided into two groups. The Control Group (C) will use a classic open surgery approach using ligatures with absorbable suture and ovarian resection with a scalpel blade. In the Group E, resection of ovarian structures was performed with ENSEAL® tissue sealer device. For each dog the surgical times, the intraoperative nociceptive response (measuring heart rate, respiratory rate and non-invasive blood pressure) and the intraoperative complications were measured to compare the effectiveness of the two techniques. RESULTS: The results of this study showed that the procedures performed using ENSEAL® were faster than the traditional techniques using surgical suture. Instead, the results regarding the nociception and the safety of the two procedures are similar. CONCLUSIONS: The present study shows that the use of ENSEAL® significantly shortened the surgical time. Meanwhile, its use was found to be similarly safe and efficient in terms of intra-operative nociception, as the classical techniques with absorbable suture. Canine ovariectomy using ENSEAL® device is more practical and faster than the traditional technique; the routine use of this device is considered a useful alternative for the canine neutering.