@article{mckay_duffy_chang_beamon_moore_2023, title={Biomechanical evaluation of three adjunctive methods of orthopedic tension band-wire fixation to augment simulated patella tendon repairs in dogs}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.14000}, abstractNote={AbstractObjectiveTo 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 designRandomized, ex vivo.Sample populationPaired hindlimbs from 32 dog cadavers.MethodsPatellar 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.ResultsCombined 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).ConclusionCombined transpatellar and suprapatellar adjunctive TBW augmentation for simulated PT repairs was biomechanically superior to either transpatellar or suprapatellar TBWF alone.Clinical significanceCombined 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.}, journal={VETERINARY SURGERY}, author={McKay, Rachel M. and Duffy, Daniel J. and Chang, Yi-Jen and Beamon, Weston and Moore, George E.}, year={2023}, month={Aug} } @article{hawbecker_duffy_chang_moore_2023, title={Influence of Kirschner-Wire Insertion Angle on Construct Biomechanics following Tibial Tuberosity Osteotomy Fixation in Dogs}, ISSN={["2567-6911"]}, DOI={10.1055/s-0042-1759868}, abstractNote={Abstract Objectives The aim of this study was to evaluate the effect of Kirschner wire insertion angle on the biomechanical characteristics following tibial tuberosity osteotomy fixation in dogs. Study Design Twelve pairs of cadaveric tibia were harvested and randomly assigned to two treatment groups. Kirschner wires were placed either transversely (0 degrees) or placed caudodistally (30 degrees) with respect to the tibial tuberosity osteotomy. Each limb acted as its own respective control. Radiographic analysis allowed for the calculation of Kirschner wire insertion angle variance. Constructs were tested to monotonic failure while evaluating yield, peak, and failure forces, construct stiffness, and failure mode. Results Kirschner wire insertion angles were 1.1 ± 2.2 degrees and 30.5 ± 2.3 degrees, respectively, for 0-degree and 30-degree groups (p <0.0001). Yield (p = 0.0095), peak (p <0.024) and failure loads (p <0.030) were all significantly greater for Kirschner wires inserted at an angle of 0 degrees compared with 30 degrees. Construct stiffness did not differ regardless of insertion angle (p = 0.068). Failure mode did not differ (p = 0.87) with tibial tuberosity avulsion and Kirschner wire pull-out seen in the majority of constructs (67%). Conclusion Kirschner wires placed transversely (0 degrees) for tibial tuberosity osteotomy fixation were biomechanically superior, increasing yield, peak, and failure forces by 1.6 times, 1.3 times, and 1.4 times, respectively, to those placed in a caudodistal (30 degrees) orientation. Kirschner wire insertion angle is an important consideration following tibial tuberosity osteotomy in dogs, with Kirschner wires placed at 0 degrees conferring increased resistance of the repair to construct deformation.}, journal={VETERINARY AND COMPARATIVE ORTHOPAEDICS AND TRAUMATOLOGY}, author={Hawbecker, Tyler J. and Duffy, Daniel J. and Chang, Yi-Jen and Moore, George E.}, year={2023}, month={Jan} } @article{haas_duffy_kendall_chang_moore_2023, title={Influence of three different closure techniques on leakage pressures and leakage location following partial cystectomies in normal dogs}, ISSN={["2053-1095"]}, DOI={10.1002/vms3.1137}, abstractNote={AbstractBackgroundTransitional 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.ObjectiveTo determine the influence of three closure techniques on ex vivo leakage pressures and leakage location following canine partial cystectomy.MethodsSpecimens 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.ResultsOversewn 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.ConclusionsPlacement 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.}, journal={VETERINARY MEDICINE AND SCIENCE}, author={Haas, Jason M. and Duffy, Daniel J. and Kendall, Allison and Chang, Yi-Jen and Moore, George E.}, year={2023}, month={Jun} } @article{beamon_duffy_chang_moore_2022, title={Effect of calcanean bone-tunnel orientation for teno-osseous repair in a canine common calcanean tendon avulsion model}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13796}, abstractNote={AbstractObjectiveTo determine the influence of bone‐tunnel anchoring technique on teno‐osseous repair of the common calcanean tendon (CCT) in dogs.Study designRandomized, ex vivo, biomechanical.PopulationForty‐two skeletally mature canine hindlimbs.MethodsCanine hindlimbs were dissected to produce a model simulating avulsion of the CCT and accessory tendons from the calcaneus. Hindlimbs were randomized to 1 of 3 anchoring techniques (n = 14/group): a single transverse tunnel (TT), vertical tunnels (VT), or modified bone tunnels (MT) for teno‐osseous repair in a 3‐loop‐pulley (3LP) pattern using 0 USP polypropylene. Yield, peak and failure loads, construct stiffness, loads to produce a 3 mm teno‐osseous gap, and failure modes were compared between groups.ResultsThe only difference detected consisted of TT constructs yielding at loads 25% higher than MT constructs (P = .027).ConclusionAlthough yield loads were lower in MT constructs than other groups, the bone‐tunnel anchoring techniques tested here did not appear to influence the biomechanical properties or gapping characteristics of teno‐osseous repairs in this canine CCT avulsion model.Clinical significanceAll drilling techniques and bone‐tunnel orientations tested in the study reported here offer viable options to reattach the CCT to the calcaneus. Surgeons should evaluate how bone‐tunnel orientation may affect placement of adjunctive fixation methods to stabilize the talocrural joint after primary CCT repair in dogs.}, journal={VETERINARY SURGERY}, author={Beamon, Weston L. and Duffy, Daniel J. and Chang, Yi-Jen and Moore, George E.}, year={2022}, month={Mar} } @article{downey_duffy_chang_fisher_moore_2022, title={Effect of epitendinous suture augmentation to a double Krackow suture pattern for canine gastrocnemius tendon repair}, volume={83}, ISSN={["1943-5681"]}, DOI={10.2460/ajvr.21.07.0100}, abstractNote={Abstract OBJECTIVE To evaluate the effect of a double Krackow suture pattern (DK), with and without epitendinous suture augmentation (ES), in a canine gastrocnemius tendon (GT) model. SAMPLE Paired GTs from 12 adult dog cadavers and 4 control GT. PROCEDURES GTs were assigned to 2 groups (n = 12/group). Transverse tenotomy was performed and repaired with a DK or DK + ES. Yield, peak, and failure force, stiffness, occurrence of 1-and 3-mm gapping, and failure mode were examined. RESULTS Yield, peak, and failure loads were greater for DK + ES. Yield force was 48% greater for DK + ES (mean ± SD, 149.56 ± 53.26 N) versus DK (101.27 ± 37.17 N; P = 0.017). Peak force was 45% greater for DK + ES P < 0.001). Failure force was 47% greater for DK + ES (193.752 ± 31.43 N) versus DK (131.54 ± 22.28 N; P < 0.001). Construct stiffness was 36% greater for DK + ES (P = 0.04). All 12 DK and 10 of 12 DK + ES repairs produced a 1-mm gap, with all DK and 4 DK + ES repairs producing a 3-mm gap (P < 0.001). Loads required to create a 3-mm gap were significantly greater for DK + ES (P < 0.013). Suture breakage occurred in all DK repairs, which differed from DK + ES, where suture breakage (7/12) and tissue failure (5/12; P = 0.037) predominated. CLINICAL RELEVANCE Augmentation of a primary DK repair with an ES significantly improved construct strength in canine GT constructs while increasing loads required to cause 1- and 3-mm gap formation, respectively. ES augmentation is a simple technique modification that can be used to significantly increase construct strength, compared with DK alone. }, number={7}, journal={AMERICAN JOURNAL OF VETERINARY RESEARCH}, author={Downey, Amy C. and Duffy, Daniel J. and Chang, Yi-Jen and Fisher, Matthew B. and Moore, George E.}, year={2022}, month={Jul} } @article{chang_duffy_beamon_moore_2022, title={Ex vivo biomechanical characteristics and effects on gap formation of using an internal fixation plate to augment primary three-loop pulley repair of canine gastrocnemius tendons}, volume={83}, ISSN={["1943-5681"]}, DOI={10.2460/ajvr.21.07.0088}, abstractNote={Abstract OBJECTIVE To evaluate the effects of using an internal fixation plate to augment primary 3-loop pulley (3LP) repair of canine gastrocnemius tendons (GTs). SAMPLE 48 cadaveric GTs from 24 adult dogs. PROCEDURES GTs were dissected free from other tissues, transected, and randomly assigned to 4 groups (n = 12/group). GTs were repaired with 2-0 polypropylene with a 3LP repair alone or a 3LP repair augmented with a 3-hole veterinary cuttable plate (3VCP), a 5-hole veterinary cuttable plate (5VCP), or a 7-hole veterinary cuttable plate (7VC P). Biomechanical loads, construct stiffness, gap formation, and failure modes were compared between groups. RESULTS Yield, peak, and failure loads were all significantly increased for the 5VCP and 7VCP groups, compared with the 3LP alone group. Increasing plate length from 3VCP to 5VCP and from 3VCP to 7VCP increased yield, peak, and failure loads. No differences were found between the 3LP and 3VCP groups with regard to yield and peak loads, but failure load was increased in the 3VCP group. Loads to create 1-mm and 3-mm gaps were significantly greater for the 5VCP and 7VCP groups, compared with the 3LP alone and 3VCP groups. Mode of plate attachment failure differed among groups. CLINICAL RELEVANCE Tendon plate augmentation may be a viable surgical option to increase the strength of the tenorrhaphy in dogs. However, in vivo studies evaluating the effects of plate augmentation on the tendon blood supply and progression of healing are needed prior to clinical application. }, number={4}, journal={AMERICAN JOURNAL OF VETERINARY RESEARCH}, author={Chang, Yi-Jen and Duffy, Daniel J. and Beamon, Wes and Moore, George E.}, year={2022}, pages={305–311} } @article{duffy_chang_moore_2022, title={Influence of barbed suture oversew of the transverse staple line during functional end-to-end stapled anastomosis in a canine jejunal enterectomy model}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13827}, abstractNote={AbstractObjectiveTo evaluate the influence of barbed suture oversew of the transverse staple line during functional end‐to‐end stapled anastomosis (FEESA) in dogs.Study designRandomized, experimental, ex vivo.Animals or sample populationGrossly normal jejunal segments from 14 adult canine cadavers.MethodsNinety‐eight jejunal segments (n = 14/FEESA group, n = 14 controls) were harvested and randomly assigned to a control group, FEESA + monofilament suture oversew, FEESA + unidirectional barbed suture oversew or FEESA + bidirectional barbed suture oversew. Oversew techniques were performed using a Cushing suture pattern. Initial (ILP) and maximum leakage pressure (MLP), repair time (s), and location of observed leakage were recorded.ResultsNo differences were detected in ILP (p = .439) or MLP (p = .644) respectively between experimental groups. Repairs times using barbed suture were ~ 18% faster (~25 s faster; p < .001) compared to monofilament suture. There was no difference between barbed suture types (p = .697). Mean ILP (p < .001) and MLP (p < .0001) were 6.6x and 5.1x greater respectively in the control group. Leakage location occurred predominately at the crotch of the FEESA in all groups.ConclusionFEESAs closed with a transverse staple line oversew using barbed suture, regardless of barb orientation, were completed faster and resulted in similar resistance to anastomotic leakage compared to monofilament suture.Clinical significanceOversewing the transverse staple line following FEESA using barbed suture offers similar resistance to anastomotic leakage, and may be associated with decreased surgical times in dogs compared to monofilament suture. Further studies are necessary to determine the benefits of barbed suture use in both open and laparoscopic gastrointestinal surgical applications following FEESA in dogs.}, journal={VETERINARY SURGERY}, author={Duffy, Daniel J. and Chang, Yi-Jen and Moore, George E.}, year={2022}, month={May} } @article{duffy_chang_moore_2022, title={Influence of crotch suture augmentation on leakage pressure and leakage location during functional end-to-end stapled anastomoses in dogs}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13764}, abstractNote={AbstractObjectiveTo determine the influence of anastomotic crotch suture augmentation on leakage pressures and leakage location following intestinal functional end‐to‐end stapled anastomosis (FEESA) in dogs.Study designEx vivo, randomized, experimental.Sample populationChilled jejunal segments from 3 adult dogs.MethodsJejunal specimens were tested within 24 hours of collection. A FEESA was performed and randomly assigned to 1 of 4 treatment groups (n = 12/group): (1) no crotch suture (NCS); (2) simple interrupted crotch suture (SICS); (3) two simple interrupted crotch sutures (TCS) placed laterally on opposing jejunal limbs; (4) simple continuous crotch suture (SCCS) augmentation. Crotch sutures were performed using 3‐0 USP polydioxanone. Initial (ILP) and maximal (MLP) leakage pressures (Mean ± SD mm Hg) and leakage location were recorded and compared between groups.ResultsInitial leakage pressure was greater after placement of TCS (37.8 ± 6.4, P < .039) and SCCS (47.6 ± 11.0, P < .002) than NCS (27.1 ± 2.5) and SICS (33.0 ± 6.0). Maximal leakage pressure was greater in specimens including SICS, TCS, and SCCS than those without crotch suture augmentation (P < .043). Leakage occurred at the anastomotic crotch in 8/12 NCS, 6/12 SICS, 11/12 TCS, and 12/12 SCCS constructs (P < .001).ConclusionAugmentation of FEESA with TCS and SCCS increased ILP and decreased the occurrence of leakage from the anastomotic crotch, while all methods of anastomotic crotch augmentation increased MLP.Clinical significanceAugmenting the FEESA with crotch suture(s) improved the resistance of the jejunal anastomosis to leakage in normal cadaveric segments. Placing 2 crotch sutures or use of a simple continuous pattern for anastomotic augmentation appeared to be superior to the placement of a single suture.}, journal={VETERINARY SURGERY}, author={Duffy, Daniel J. and Chang, Yi-Jen and Moore, George E.}, year={2022}, month={Jan} } @article{chang_duffy_moore_2022, title={Loop diameter of a modified Kessler locking-loop suture affects in vitro tensile strength and gapping characteristics of canine flexor tendon repairs}, volume={83}, ISSN={["1943-5681"]}, DOI={10.2460/ajvr.21.12.0212}, abstractNote={Abstract OBJECTIVE To evaluate effects of loop diameter of a modified Kessler locking-loop (LL) suture on in vitro tensile strength and gapping characteristics of canine flexor tendon repairs. SAMPLE 48 cadaveric superficial digital flexor tendons from 24 adult medium- to large-breed dogs. PROCEDURES Flexor tendons were randomly assigned to 4 groups (n = 12/group) and repaired with 2-0 polypropylene in a LL pattern with loops measuring 1, 2, 3, or 4 mm in diameter. Biomechanical loads, gap formation between tendon ends, and failure modes were evaluated and compared between groups. RESULTS Increasing loop diameter from 1 to 4 mm significantly increased yield (P = .048), peak (P < .001), and failure (P < .001) loads. There were no significant differences in yield, peak, and failure loads between 1- and 2-mm loops. Load to 3-mm gap formation was significantly (P < .001) greater for 4-mm loops, compared with 1-, 2-, and 3-mm loops. Failure mode did not differ significantly among experimental groups, with 46 of 48 (96%) of constructs failing because of suture breakage. CLINICAL RELEVANCE Loop diameter of a LL suture pattern is an important biomechanical variable that influences construct biomechanics of canine tendon suture repairs. Loop diameters > 3 mm are recommended when the size of the tendon allows. Further studies are necessary to determine the in vivo effect of these findings, particularly the effects on tendon blood supply. }, number={9}, journal={AMERICAN JOURNAL OF VETERINARY RESEARCH}, author={Chang, Yi-Jen and Duffy, Daniel J. and Moore, George E.}, year={2022}, month={Sep} } @article{duffy_beamon_chang_moore_2022, title={Loop modification of the traditional three-loop pulley pattern improves the biomechanical properties and resistance to 3-mm gap formation in a canine common calcanean teno-osseous avulsion model}, volume={83}, ISSN={["1943-5681"]}, DOI={10.2460/ajvr.21.09.0139}, abstractNote={Abstract OBJECTIVE To compare the biomechanical properties and gapping characteristics following loop modification of a 3-loop-pulley (3LP) pattern in an ex vivo canine common calcaneal tendon (CCT) avulsion repair model. SAMPLE 56 skeletally mature hindlimbs from 28 canine cadavers. PROCEDURES The CCTs were randomized to 1 of 4 experimental groups (n = 14/group) then sharply transected at the teno-osseous junction. Groups consisted of a 3LP, 4-loop-pulley (4LP), 5-loop-pulley (5LP), or 6-loop-pulley (6LP) pattern with loops placed 60° apart using size-0 polypropylene. Yield, peak, and failure loads, construct stiffness, loads to produce a 3-mm teno-osseous gap, and failure mode were evaluated and compared between groups. RESULTS Yield (P = 0.001), peak (P < 0.001), and failure loads (P < 0.001), construct stiffness (P < 0.001), and loads to 3-mm gap formation (P = 0.005) were all significantly greater for 6LP compared to all other groups. Mode of failure did not differ among groups (P = 0.733) with 75% (42/56) of repairs failing by mechanism of core sutures pulling through the tendinous tissue. Pattern modification by increasing the number of loops increased the repair site strength by 1.4, 1.6, and 1.8 times for 4LP, 5LP, and 6LP compared to 3LP, respectively. CLINICAL RELEVANCE Increasing the number of suture loops compared to a traditional 3LP repair is a relatively simple technique modification that significantly increases teno-osseous repair site strength and loads required to cause 3-mm gap formation. The results of this study justify further focused investigation of increasing the number of suture loops in vivo for teno-osseous CCT repair in dogs. }, number={8}, journal={AMERICAN JOURNAL OF VETERINARY RESEARCH}, author={Duffy, Daniel J. and Beamon, Weston L. and Chang, Yi-Jen and Moore, George E.}, year={2022}, month={Aug} } @article{dimichele_duffy_chang_moore_2022, title={Superficial digital flexor tendon graft augmentation improves the tensile strength and resistance to gap formation following primary gastrocnemius tendon repair in dogs}, volume={83}, ISSN={["1943-5681"]}, DOI={10.2460/ajvr.22.03.0039}, abstractNote={Abstract OBJECTIVE To evaluate the influence of superficial digital flexor tendon (SDFT) graft augmentation on the biomechanical properties and resistance to gap formation in a canine gastrocnemius tendon repair model. SAMPLE POPULATION 28 canine cadaveric hind limbs. PROCEDURES Respective hindlimbs from each dog were randomized to one of two groups (n = 14/group) using a 3-loop–pulley (3LP) pattern alone or 3LP + SDFT graft augmentation. Biomechanical parameters evaluated included yield, peak, and failure loads; tensile loads required to create 1- and 3-mm gap formations; and mode of construct failure. RESULTS Mean yield and failure loads for the 3LP + SDFT graft group were 483.6 ± 148.0 N and 478.3 ± 147.9 N, respectively, and were greater compared to the 3LP group (34.2 ± 6.7 N and 34.0 ± 8.0 N, P < .0001). Loads to both 1- and 3-mm gap formations for the 3LP + SDFT graft group were greater compared to 3LP alone (P < .001). Failure modes did not differ between groups (P = .120), with constructs failing most commonly by suture pulling through opposed tendinous tissues whereas SDFT grafts remained intact. CLINICAL RELEVANCE SDFT graft augmentation increased yield, peak, and failure forces 14-fold across all examined biomechanical variables compared to the 3LP group. The 3LP + SDFT graft group required 3.6X and 6.5X greater loads to cause a 1- and 3-mm gap, respectively, between tendon ends. These data support the biomechanical advantages of SDFT graft augmentation to increase repair-site strength and to promote resistance to gap formation of the tenorrhaphy. Additional in vivo studies are required to determine the effect of SDFT augmentation on clinical function and active limb use after graft harvest in dogs. }, number={9}, journal={AMERICAN JOURNAL OF VETERINARY RESEARCH}, author={DiMichele, Julianna K. and Duffy, Daniel J. and Chang, Yi-Jen and Moore, George E.}, year={2022}, month={Sep} } @article{duffy_chang_fisher_moore_2021, title={Biomechanical analysis of accessory tendon graft augmentation for primary gastrocnemius tendon reconstruction in dogs}, volume={50}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13645}, abstractNote={AbstractObjectiveTo evaluate the effect of accessory tendon graft (ATG) augmentation as an adjunct to a core locking‐loop (LL) and epitendinous suture (ES) repair in a gastrocnemius tendon (GT) model.Study DesignRandomized, ex vivo, biomechanical.PopulationTwenty‐two canine GT musculotendinous constructs.MethodsGT repair constructs were randomly divided into two groups (n = 10/group). After transection, paired GT were repaired with LL + ES alone or with concurrent ATG augmentation. Yield, peak and failure loads, tensile loads required to create 1 and 3 mm gapping, and failure modes were evaluated. Four GT were used as intact controls for validation of testing methodology. ATG constructs were compared to LL + ES and control specimens.ResultsYield (p < .0001), peak (p = .0001) and failure loads (p = .0003) were greater when ATG was used for repair. Greater force was required to cause 1 mm (p = .0001) and 3 mm (p = .0002) gap formation in the ATG group, however, the frequency of gap formation did not differ between groups. All repaired constructs failed exclusively by suture pull‐through.ConclusionAutologous ATG augmentation as an adjunct to primary GT repair increased yield, peak and failure forces by approximately 1.6×, 1.9×, 1.8× respectively and required 2.1× greater force to cause 1 and 3 mm formation respectively compared to LL + ES repairs alone.Clinical SignificanceATG augmentation should be considered as an autologous method to support and strengthen the primary GT repair. These results justify studies to determine the effect of ATG on clinical function following graft harvest in dogs.}, number={5}, journal={VETERINARY SURGERY}, author={Duffy, Daniel J. and Chang, Yi-Jen and Fisher, Matthew B. and Moore, George E.}, year={2021}, month={Jul}, pages={1147–1156} } @article{duffy_chang_fisher_moore_2021, title={Biomechanical evaluation of a novel barbed suture pattern with epitendinous suture augmentation in a canine flexor tendon model}, volume={50}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13653}, abstractNote={AbstractObjectiveTo determine the effect of a novel barbed suture pattern (NBSP) compared to a three‐loop‐pulley (3LP) with and without epitendinous suture (ES) augmentation on the biomechanical strength and gap formation of repaired canine tendons.Study DesignEx vivo, cadaveric, randomized, experimental study.Sample PopulationForty, adult superficial digital flexor tendons (SDFT).MethodsSDFT were randomly assigned to one of four groups (n = 10/group). Sharp tenotomy was performed and repaired with 3LP, NBSP, 3LP + ES, and NBSP + ES. Constructs were tested to failure while evaluating yield, peak, and failure loads, loads at 1 and 3 mm gap formation, and failure mode.ResultsConstructs augmented with ES sustained 80% greater yield (p < .001), peak (p < .001), and failure (p < .001) loads, with no difference between 3LP + ES and NBSP + ES constructs regarding peak (p = .614), and failure forces (p = .865). Loads resulting in 1 and 3 mm gap formation were greater when constructs were augmented with an ES (p ≤ .003). Failure mode differed between groups (p < .001), occurring predominantly due to suture pull‐through in 3LP and NBSP groups compared to tissue failure distant to the repair site in ES augmented constructs.ConclusionTendons repaired with the NBSP used in this study resisted similar forces as those repaired with 3LP. Augmentation with an ES improved the biomechanical properties of repaired constructs, including resistance to gap formation.Clinical RelevanceThe NBSP repair tested here may be advantageous over monofilament suture repair as it uses a similar‐sized barbed core suture but eliminates the requirement for knot tying.}, number={5}, journal={VETERINARY SURGERY}, author={Duffy, Daniel J. and Chang, Yi-Jen and Fisher, Matthew B. and Moore, George E.}, year={2021}, month={Jul}, pages={1128–1136} } @article{corrie_duffy_chang_moore_2021, title={Effect of knot location on the biomechanical strength and gapping characteristics of ex vivo canine gastrocnemius tenorrhaphy constructs}, volume={82}, ISSN={["1943-5681"]}, DOI={10.2460/ajvr.21.03.0038}, abstractNote={Abstract OBJECTIVE To evaluate the effect of knot location on the biomechanical strength and gapping characteristics of ex vivo canine gastrocnemius tenorrhaphy constructs. SAMPLE 36 cadaveric gastrocnemius tendons from 18 adult dogs. PROCEDURES Tendons were randomly assigned to 3 groups (12 tendons/group) and sharply transected and repaired by means of a core locking-loop suture with the knot at 1 of 3 locations (exposed on the external surface of the tendon, buried just underneath the external surface of the tendon, or buried internally between the apposed tendon ends). All repairs were performed with size-0 polypropylene suture. All constructs underwent a single load-to-failure test. Yield, failure, and peak forces, mode of failure, and forces required for 1- and 3-mm gap formation were compared among the 3 knot-location groups. RESULTS Mean yield, failure, and peak forces and mean forces required for 1- and 3-mm gap formation did not differ significantly among the 3 groups. The mode of failure also did not differ significantly among the 3 groups, and the majority (33/36 [92%]) of constructs failed owing to the suture pulling through the tendinous substance. CONCLUSIONS AND CLINICAL RELEVANCE Final knot location did not significantly affect the biomechanical strength and gapping characteristics of canine gastrocnemius tenorrhaphy constructs. Therefore, all 3 evaluated knot locations may be acceptable for tendon repair in dogs. In vivo studies are necessary to further elucidate the effect of knot location in suture patterns commonly used for tenorrhaphy on tendinous healing and collagenous remodeling at the repair site. }, number={12}, journal={AMERICAN JOURNAL OF VETERINARY RESEARCH}, author={Corrie, Jessica L. and Duffy, Daniel J. and Chang, Yi-Jen and Moore, George E.}, year={2021}, month={Dec}, pages={942–947} } @article{duffy_cocca_chang_moore_2021, title={Evaluation of staple line reinforcement after partial gastrectomy closure in an ex vivo canine model}, volume={50}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13550}, abstractNote={AbstractObjectiveTo determine the influence of stapling on leakage pressures after canine partial gastrectomy.Study designEx vivo study.Sample populationGastric specimens from 24 adult canine cadavers.MethodsPartial gastrectomy constructs were assigned to one of three closure techniques (n = 8 per group): group 1, stapled closure with a 90‐mm thoracoabdominal stapling device and a 4.8‐mm staple cartridge; group 2, hand‐sewn double‐layer inverting suture closure with 3‐0 glycomer 631; and group 3, staple line reinforcement with an inverting Cushing suture pattern. Leakage and pressure testing were performed. Initial leakage pressure (ILP), maximal leakage pressure (MLP), and leakage location were recorded. Significance was set at P < .05.ResultsPlacement of a Cushing suture (group 3) increased ILP and MLP by 3.2‐fold and 2.8‐fold, respectively, compared with stapled closures alone (P < .001). Constructs closed with double‐layer suture closure reached ILP and MLP 4.5‐fold and threefold greater, respectively, compared with those with stapled closures alone (P < .001). Maximal leakage pressure did not differ between groups 2 and 3 (P = .14). Leakage occurred from the inverting suture line in all constructs of groups 2 and 3 and from staple holes in six of eight group 1 constructs.ConclusionDouble‐layer suture closure of canine partial gastrectomies achieved superior biomechanical properties compared with stapled closure techniques. Reinforcing staple closures with an inverting suture line improved resistance to leakage.Clinical significanceReinforcing single‐layer closure of partial gastrectomies with an inverting Cushing pattern is recommended to improve resistance to leakage. In vivo investigation is warranted to evaluate influence of closure technique on gastric healing, postoperative stasis, ischemic injury, and postoperative dehiscence.}, number={2}, journal={VETERINARY SURGERY}, author={Duffy, Daniel J. and Cocca, Christina J. and Chang, Yi-Jen and Moore, George E.}, year={2021}, month={Feb}, pages={435–443} } @article{curcillo_duffy_chang_moore_2021, title={Ex Vivo Biomechanical Assessment of a Novel Multi-Strand Repair of Canine Tendon Lacerations}, ISSN={["2567-6911"]}, DOI={10.1055/s-0041-1725014}, abstractNote={Abstract Objective This study aimed to evaluate the effect of increasing the number of suture strands traversing the transection site, level of suture purchase and depth of suture penetrance on the biomechanical properties of repaired gastrocnemius tendons. Study Design Thirty-eight adult cadaveric gastrocnemius tendons were randomized, transected and repaired with either two-, four- or six-strand locking multi-level repair. Tensile loads required to create a 1 and 3 mm gap, yield, peak and failure loads and failure mode were analysed. Significance was set at p < 0.05. Results Mean ± standard deviation yield, peak and failure force for six-strand repairs was 90.6 ± 22.1 N, 111.4 ± 15.2 N and 110.3 ± 15.1 N respectively. This was significantly greater compared with both four-strand (55.0 ± 8.9 N, 72.9 ± 7.8 N and 72.1 ± 8.2 N) and two-strand repairs (24.7 ± 8.3 N, 36.5 ± 6.0 N and 36.1 ± 6.3 N) respectively (p < 0.001). Occurrence of 3 mm gap formation was significantly less using six-strand repairs (p < 0.001). Mode of failure did not differ between groups with all repairs (36/36; 100%) failing by suture pull-through. Conclusion Pattern modification by increasing the number of suture strands crossing the repair site, increasing points of suture purchase from the transection site and depth of suture penetrance is positively correlated with repair site strength while significantly reducing the occurrence of gap formation in a canine cadaveric model. Additional studies in vivo are recommended to evaluate their effect on tendinous healing, blood supply and glide resistance prior to clinical implementation.}, journal={VETERINARY AND COMPARATIVE ORTHOPAEDICS AND TRAUMATOLOGY}, author={Curcillo, Chiara P. and Duffy, Daniel J. and Chang, Yi-Jen and Moore, George E.}, year={2021}, month={Mar} } @article{chiu_duffy_chang_gaffney_fisher_2021, title={Ex vivo evaluation of novel core tenorrhaphy patterns in dogs}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13678}, abstractNote={AbstractObjectiveTo compare the biomechanical properties and gapping characteristics of four novel tenorrhaphy patterns in a canine flexor tendon model.Study DesignEx vivo, randomized, biomechanical study.Sample PopulationSuperficial digital flexor tendons of 60 forelimbs (30 dogs).MethodsEach tendon was transected 25 mm distal to its musculotendinous junction prior to tenorrhaphy with 2‐0 polypropylene. Repair patterns included the three‐loop pulley (3LP, control), exposed double‐cross‐lock (ExDCrL), embedded double‐cross‐lock (EmDCrL), triple‐circle‐lock (TCiL), and Modified‐Tang patterns (MTang) were randomly assigned to each experimental group (n = 12/group). Yield, peak, and failure loads, gap formation and failure modes were compared.ResultsTendons repaired with ExDCrL (p < .0001), EmDCrL (p < .0001), and MTang (p < .0001) sustained yield, peak, and failure loads ~2.2x, ~2.0x, and ~1.9x, respectively, greater than those repaired with 3LP. Loads to 1 and 3 mm gapping were also higher for ExDCrL (p < .0001), EmDCrL (p < .0004), and MTang constructs (p < .0017) compared to 3LP. Although TCiL constructs sustained higher loads, their resistance to gap formation did not differ from that of 3LP repairs. Failure mode differed between groups (p < .0001), EmDCrL, ExDCrL, MTang, and TCiL constructs failing predominantly by suture breakage compared to 3LP repairs that failed by suture pull‐through.ConclusionUse of novel patterns ExDCrL, EmDCrL, and MTang improved resistance to loads and gap formation and were biomechanically superior compared to 3LP in healthy canine tendon repairs.Clinical SignificanceThese results justify in vivo evaluation of ExDCrL, EmDCrL, or MTang pattern for tenorrhaphy in dogs.}, journal={VETERINARY SURGERY}, author={Chiu, King Wa and Duffy, Daniel J. and Chang, Yi-Jen and Gaffney, Lewis and Fisher, Matthew B.}, year={2021}, month={Jul} } @article{chang_duffy_moore_2021, title={Influence of preconstructed effector loop location using a barbed unidirectional suture on leakage pressures following canine enterotomy closure}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13710}, abstractNote={AbstractObjectiveTo evaluate the influence of preconstructed effector loop location using a barbed unidirectional suture on leakage pressures following canine enterotomy closure.Study designRandomized, experimental, cadaveric.Animals or sample populationGrossly normal jejunal segments from three canine cadavers.MethodsJejunal segments were harvested and randomly assigned based upon effector loop location from the beginning of the incisional line. Groups (n = 12/group) included 0 mm, 5 mm, 10 mm, 15 mm, and intact controls (n = 6/group), repaired using a 3–0 unidirectional barbed suture in a simple continuous pattern. Initial leakage pressure (ILP), maximum intraluminal pressure (MIP), repair time, and leakage location were recorded.ResultsMean ILP for 0 mm group (24.42 ± 8.43 mmHg) was lower (p ≤ .001) compared to all experimental groups with ILP ~40% lower. There was no difference in MIP among experimental groups (p = .239). Repair time increased (p < .0001) as the distance of the effector loop increased ≥5 mm from the beginning of the incisional line. Leakage location differed among groups (p < .001) with leakage in the 0 mm group from the incisional line (75%), compared to leakage from predominantly from the suture holes in other groups, respectively.ConclusionEffector loop location influenced ILP and leakage location. Effector loops placed at the beginning of the incisional line (0 mm) decreased ILP compared to loops placed at 5, 10, and 15 mm.Clinical significanceEffector loop location using a unidirectional barbed suture should be placed ≥5 mm from beginning of the incisional line for enterotomy closure. Further in vivo studies are necessary to determine the clinical significance of these findings.}, journal={VETERINARY SURGERY}, author={Chang, Yi-Jen and Duffy, Daniel J. and Moore, George E.}, year={2021}, month={Aug} } @article{duffy_curcillo_chang_gaffney_fisher_moore_2020, title={Biomechanical evaluation of an autologous flexor digitorum lateralis graft to augment the surgical repair of gastrocnemius tendon laceration in a canine ex vivo model}, volume={49}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13453}, abstractNote={AbstractObjectiveTo evaluate the effect of an autologous flexor digitorum lateralis (FDL) graft to augment a three‐loop pulley (3LP) core repair in a canine cadaveric gastrocnemius tendon (GT) laceration model.Study designEx vivo, biomechanical study.Sample populationTwenty‐six canine cadaveric hind limbs.MethodsTendons were divided into two groups (n = 13). After sharp transection, paired GT were repaired with 3LP or 3LP + FDL tendon augmentation. Yield, peak and failure loads, tensile loads required to create 1 and 3‐mm gapping, and failure modes were analyzed. Significance was set at P < .05.ResultsYield and failure force (mean ± SD) for 3LP + FDL were 134.9 ± 44.1 N and 205.4 ± 46.4 N, respectively, which were greater than for 3LP alone (67.9 ± 12.2 N and 91.8 ± 9.9 N, respectively, P < .0001). No constructs (0%) formed 1 or 3‐mm gaps in the 3LP + FDL graft group compared with 84% and 39% for 3LP, respectively (P < .0001). Failure modes were different between groups (P < .001), with 85% of 3LP + FDL constructs failing by tissue rupture at the myotendinous junction, distant to the repair site.ConclusionAddition of an autologous FDL graft to a core 3LP tendon repair increased yield, peak, and failure forces by twofold, 2.3‐fold, and 2.2‐fold, respectively, compared with core 3LP alone while preventing the occurrence of gap formation.Clinical significanceUse of FDL tendon augmentation for GT laceration may increase repair site strength and resist gap formation better than 3LP core suture use alone. Additional studies are required in vivo to determine the effect of FDL graft augmentation on clinical function.}, number={8}, journal={VETERINARY SURGERY}, author={Duffy, Daniel J. and Curcillo, Chiara P. and Chang, Yi-Jen and Gaffney, Lewis and Fisher, Matthew B. and Moore, George E.}, year={2020}, month={Dec}, pages={1545–1554} } @article{duffy_chang_fisher_moore_2020, title={Effect of partial vs complete circumferential epitendinous suture placement on the biomechanical properties and gap formation of canine cadaveric tendons}, volume={49}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13494}, abstractNote={AbstractObjectiveTo determine the effect of partial vs complete circumferential epitendinous suture (ES) placement in addition to a core suture on the biomechanical strength and gapping characteristics of repaired canine tendinous constructs.Study designEx vivo, biomechanical study.Sample populationThirty‐six canine superficial digital flexor tendons.MethodsSuperficial digital flexor tendons were randomly assigned to three groups (n = 12), sharply transected and repaired with a core locking‐loop suture with Group 1 a partial circumferential ES, 180° on the palmar side; Group 2 a complete circumferential ES, 360° and double knotting technique; or Group 3 a complete circumferential ES, 360° and single knotting technique. After preloading, constructs were distracted to monotonic failure. Failure mode, gap formation, yield, peak, and failure forces were analyzed.ResultsMean yield (group 1 = 68.6 N, group 2 = 106.5 N, group 3 = 114 N, P < .013), peak (group 1 = 92.8 N, group 2 = 134.6 N, group 3 = 147.3 N; P < .001), and failure (group 1 = 88.7 N, group 2 = 133.0 N, group 3 = 145.5 N, P < .001) loads differed between groups. No difference in yield (P = .874), peak (P = .434), or failure load (P = .434) was detected between complete circumferential ES groups. Force to create 1‐mm (P < .001) and 3‐mm (P < .038) gap formation was greater in specimens with complete vs partial circumferential ES placement. Complete circumferential ES repairs failed primarily by suture pull‐through compared with suture breakage in most partial circumferential ES constructs.ConclusionAddition of a complete circumferential ES with a single or double knotting technique increased the biomechanical strength of normal tendon repairs while reducing gap formation compared with partial ES placement alone.Clinical significanceComplete circumferential ES is recommended over partial ES placement.}, number={8}, journal={VETERINARY SURGERY}, author={Duffy, Daniel J. and Chang, Yi-Jen and Fisher, Matthew B. and Moore, George E.}, year={2020}, month={Dec}, pages={1571–1579} } @article{duffy_chang_balko_moore_2020, title={Effect of presurgical storage conditions on leakage pressures of enterotomy sites closed with unidirectional barbed suture material in fresh, chilled, and frozen-thawed cadaveric canine jejunal specimens}, volume={81}, ISSN={["1943-5681"]}, DOI={10.2460/ajvr.81.3.220}, abstractNote={Abstract OBJECTIVE To evaluate the effect of presurgical storage conditions on leakage pressures of enterotomy sites closed with unidirectional barbed suture material in fresh, chilled, and frozen-thawed cadaveric canine jejunal specimens. SAMPLE 36 grossly normal jejunal segments obtained from 4 dog cadavers. PROCEDURES 9 jejunal segments were harvested immediately from each euthanized dog and randomly assigned to be tested within 4 hours after collection (fresh segments), stored at 4°C for 24 hours before testing (chilled segments), or stored at −20°C for 7 days and thawed at 21°C for 6 hours before testing (frozen-thawed segments). For leakage pressure testing, a 3-cm-long antimesenteric enterotomy was performed and repaired with 3-0 unidirectional barbed suture material in a simple continuous pattern in each segment. Time to complete the enterotomy, initial leakage pressure, maximum intraluminal pressure, and leakage location were recorded for each segment. RESULTS Mean ± SD initial leakage pressure for fresh, chilled, and frozen-thawed segments was 52.8 ± 14.9 mm Hg, 51.8 ± 11.9 mm Hg, and 33.3 ± 7.7 mm Hg, respectively. Frozen-thawed segments had significantly lower mean initial leakage pressure, compared with findings for fresh or chilled segments. Time to complete the enterotomy, maximum intraluminal pressure, and leakage location did not differ among groups. CONCLUSIONS AND CLINICAL RELEVANCE Leak pressure testing of cadaveric jejunal segments that are fresh or chilled at 4°C for 24 hours is recommended for enterotomy studies involving barbed suture material in dogs. Freezing and thawing of cadaveric jejunal tissues prior to investigative use is not recommended because leak pressure data may be falsely low. }, number={3}, journal={AMERICAN JOURNAL OF VETERINARY RESEARCH}, author={Duffy, Daniel J. and Chang, Yi-Jen and Balko, Julie A. and Moore, George E.}, year={2020}, month={Mar}, pages={220–226} } @article{eby_duffy_chang_gaffney_fisher_moore_2020, title={Influence of barbed epitendinous suture combined with a core locking-loop sutures to repair experimental flexor tendon lacerations}, volume={49}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13496}, abstractNote={AbstractObjectiveTo determine the influence of barbed epitendinous sutures (ES) on the biomechanical properties and gap formation of repaired canine tendons.Study designEx vivo, experimental study.Sample populationEighty (n = 16/group) canine superficial digital flexor tendons (SDFT).MethodsAfter transection, SDFT were repaired with a locking‐loop (LL) pattern alone (group 1), an LL + smooth ES with monofilament suture (group 2), an LL + V‐loc‐ES (group 3), an LL + Quill‐ES (group 4), or an LL + Stratafix‐ES (group 5). All core LL repairs were performed with 0 USP polypropylene, and all ES were placed with 2‐0 USP equivalent. Constructs were preloaded and tested to failure. Yield, peak, and failure loads; occurrence of gap formation; and failure modes were compared.ResultsYield loads were greater for groups 2 and 5 (P < .0001). Peak and failure loads were greater when an ES was used (P < .005), especially for groups 2 and 5 (P < .0001). Groups with an ES required higher loads to generate 1‐ and 3‐mm gaps compared with specimens without an ES (P < .002). Force to create 1‐ and 3‐mm gaps was greater for group 5 (P < .0001) and groups 2 and 5 (P < .0001), respectively. Failure mechanism did not differ (P = .092) between ES groups, consisting of suture breakage in 51 of 64 constructs compared with pull‐through in seven of 16 group 1 constructs.ConclusionEpitendinous suture placement improved the biomechanical properties of repaired tendons. Stratafix barbed suture performed better as an ES compared with other barbed sutures and similarly to monofilament suture.Clinical significanceStratafix barbed suture eliminates the requirement for knot tying and seems to be equivalent to smooth monofilament suture when used as an ES in this pattern.}, number={8}, journal={VETERINARY SURGERY}, author={Eby, Adam C. and Duffy, Daniel J. and Chang, Yi-Jen and Gaffney, Lewis and Fisher, Matthew B. and Moore, George E.}, year={2020}, month={Dec}, pages={1590–1599} } @article{duffy_chang_moore_2020, title={Influence of closure technique on leakage pressures in an ex vivo canine typhlectomy model}, volume={49}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13405}, abstractNote={AbstractObjectiveTo determine the influence of three closure techniques on leakage pressures of canine typhlectomies.Study designExperimental, ex vivo.Sample populationGrossly normal cecal segments from 24 adult canine cadavers.MethodsTyphlectomies were assigned to one of three closure techniques: simple continuous closure with a Parker‐Kerr pattern with 4‐0 polydioxanone (group 1), closure with a 60‐mm gastrointestinal stapler loaded with a 3.8‐mm staple cartridge (group 2), and placement of a Cushing suture to augment the stapled closure (group 3). The median (range) of initial leakage pressure (ILP) and maximum leakage pressure (MLP) was compared between groups along with leakage location.ResultsTyphlectomies in group 3 leaked at higher ILP (310 mm Hg; 188‐310) than those in groups 1 (43 mm Hg; 31‐80) and 2 (109.5 mm Hg; 68‐173; P < .0001). Maximum leakage pressure were greater in group 3 than in other groups (P < .0001). Leakage was detected in 20 of 24 (83%) typhlectomies, located at the incisional line in 13 of 24 (54%) specimens and from suture holes in seven of 24 (29%) specimens.ConclusionPlacement of a Cushing suture pattern to augment stapled incisions improved the ability of typhlectomies to sustain pressure compared with sutured or stapled cadaveric specimens alone.Clinical significanceThese results provide evidence to support placement of a Cushing suture pattern to augment the staple line for typhlectomies in dogs, although in vivo studies are required to determine the clinical significance of these findings.}, number={6}, journal={VETERINARY SURGERY}, author={Duffy, Daniel J. and Chang, Yi-Jen and Moore, George E.}, year={2020}, month={Aug}, pages={1213–1220} } @article{duffy_chang_gaffney_fisher_moore_2019, title={Effect of bite depth of an epitendinous suture on the biomechanical strength of repaired canine flexor tendons}, volume={80}, ISSN={["1943-5681"]}, DOI={10.2460/ajvr.80.11.1043}, abstractNote={Abstract OBJECTIVE To determine effects of bite depth for placement of an epitendinous suture on the biomechanical strength and gap formation of repaired canine tendons. SAMPLE 48 superficial digital flexor tendons (SDFTs) obtained from 24 canine cadavers. PROCEDURES Tendons were assigned to 3 groups (16 tendons/group). Each SDFT was transected and then repaired with a continuous epitendinous suture placed with a bite depth of 1, 2, or 3 mm for groups 1, 2, and 3, respectively. Specimens were loaded to failure. Failure mode, gap formation, yield force, peak force, and failure force were analyzed. RESULTS Yield, peak, and failure forces differed significantly between groups 1 and 3 and groups 2 and 3 but not between groups 1 and 2. Comparison of the force resisted at 1 and 3 mm of gapping revealed a significant difference between groups 1 and 3 and groups 2 and 3 but not between groups 1 and 2. Failure mode did not differ among groups; suture pull-through occurred in 43 of 48 (89.6%) specimens. CONCLUSIONS AND CLINICAL RELEVANCE Increasing bite depth of an epitendinous suture toward the center of the tendon substance increased repair site strength and decreased the incidence of gap formation. Repair of tendon injuries in dogs by use of an epitendinous suture with bites made deep into the tendon should result in a stronger repair, which potentially would allow loading and rehabilitation to begin sooner after surgery. Suture techniques should be investigated in vivo to determine effects on tendinous healing and blood supply before clinical implementation. }, number={11}, journal={AMERICAN JOURNAL OF VETERINARY RESEARCH}, author={Duffy, Daniel J. and Chang, Yi-Jen and Gaffney, Lewis S. and Fisher, Matthew B. and Moore, George E.}, year={2019}, month={Nov}, pages={1043–1049} } @article{duffy_chang_balko_moore_2020, title={Ex vivo comparison of the effect of storage temperature on canine intestinal leakage pressures}, volume={49}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13339}, abstractNote={AbstractObjectiveTo determine the effect of storage temperature on cadaveric small intestinal leakage pressures after enterotomy.Study designExperimental ex vivo study.AnimalsGrossly normal jejunal segments from four canine cadavers.MethodsThirty‐six jejunal segments (n = 12 segments/group) were harvested immediately after euthanasia and assigned to a fresh group (tested within 4 hours), chilled group (stored for 24 hours at 4°C before testing), or freeze–thaw group (frozen at −20°C for 7 days and thawed at 21°C for 6 hours before testing). A 2‐cm antimesenteric enterotomy was performed and repaired with 4‐0 monofilament suture in a simple‐continuous pattern. Initial leakage pressure (ILP), maximal intraluminal pressure (MIP), and leakage location were recorded, with testing performed at room temperature.ResultsMean ± SD ILP for fresh, chilled, and frozen–thawed specimens was 52.9 ± 8.4, 51.8 ± 11.9 and 29.8 ± 4.4 mm Hg, respectively. There was a difference in ILP among groups (P < .003), with freeze–thaw samples demonstrating lower ILP compared with other groups. There was no difference in MIP between groups (P = .186) There was a difference in leakage location among groups (P = .004), with the majority of chilled and freeze–thaw samples leaking at the suture holes compared with the incisional line in fresh samples.ConclusionFreezing and subsequent thawing prior to specimen testing reduced ILP compared with use of fresh and chilled specimens but did not affect MIP among experimental groups.Clinical significanceCadaveric canine intestinal specimens tested immediately after collection or after chilling for 24 hours should be recommended for ex vivo burst pressure assessment in dogs. Additional studies to evaluate loss in testing viability of chilled intestinal specimens are warranted to help govern experimental methodologies.}, number={3}, journal={VETERINARY SURGERY}, author={Duffy, Daniel J. and Chang, Yi-Jen and Balko, Julie A. and Moore, George E.}, year={2020}, month={Apr}, pages={496–501} }