Comparative study between lateral versus latero-ventral quadratus lumborum block for perioperative analgesia in canine laparoscopic ovariectomy.

OBJECTIVE: To compare the perioperative analgesic effect of lateral versus latero-ventral quadratus lumborum block (QLB) in dogs undergoing laparoscopic ovariectomy. STUDY DESIGN: Randomized, blinded clinical study. ANIMALS: A total of 15 client-owned female dogs undergoing laparoscopic ovariectomy. METHODS: Animals were randomly assigned to receive a bilateral QLB, performed with 0.3 mL kg-1 ropivacaine 0.5%, either with lateral (group LQLB, n = 7) or latero-ventral approach (group LVQLB, n = 7). Dogs were premedicated intramuscularly with methadone 0.2 mg kg-1 and dexmedetomidine 3 µg kg-1. General anaesthesia was induced intravenously (IV) with propofol and maintained with isoflurane. Cardiovascular and respiratory variables were continuously monitored and recorded every 5 minutes during surgery. Fentanyl 3 µg kg-1 was administered IV if there was a 20% increase in heart rate and/or mean arterial pressure from previous values recorded 5 minutes before. Meloxicam 0.2 mg kg-1 was administered IV to all dogs during recovery. The short-form of the Glasgow Composite Pain Scale was used hourly for 8 hours post-QLB. Methadone 0.2 mg kg-1 was administered IV when pain score was ≥ 6/24. A chi-square test compared the number of dogs requiring intraoperative rescue fentanyl. A Friedman test with a Dunn's post hoc was used to evaluate the trend in postoperative pain scores within each group, and a Mann-Whitney U test compared scores between the groups at each time point; p < 0.05. RESULTS: Significantly fewer dogs required intraoperative rescue fentanyl in group LQLB than in group LVQLB. No dog required postoperative rescue methadone, and there were no significant differences in pain scores. CONCLUSIONS AND CLINICAL RELEVANCE: Bilateral QLB performed with lateral approach reduced the number of dogs requiring intraoperative rescue analgesia in comparison with the latero-ventral approach. No differences were detected postoperatively, possibly owing to the confounding effects of methadone, dexmedetomidine and meloxicam.

Stifle arthrodesis in dogs using semi-circular saw: Cadaveric study.

The aim of this study was to develop a novel surgical technique for stifle arthrodesis in dogs using a semicircular saw for tibial and femoral ostectomies through a medial approach. Ten pelvic limbs from five canine cadavers underwent stifle arthrodesis. Prior to the surgical procedure, the limbs were radiographed to rule out musculoskeletal abnormalities. Additionally, the radiographs were used for surgical planning. For the tibial ostectomy, the center of the intercondylar eminences, the cranial limit of the tibial plateau, and the caudal cortex of the tibia were used as landmarks. In the femur, the groove of the insertion of the long digital extensor tendon and the caudal portion of the femoral cortex served as references. The most significant iatrogenic injury during the surgical procedures was the complete rupture of the long digital extensor tendon during the tibial cut in one of the stifles. Dome ostectomies facilitated interfragmentary contact, allowing for adjustment of the angulation between the fragments without the need for additional ostectomies or osteotomies. The medial approach provided a clear view of intra-articular structures without causing extensive damage to surrounding tissues. After the procedures, the limbs were radiographed to calculate angular measurements, and the final angulation (mean) of the knee joints was 134.7 ± 11°.

The use of fully threaded headless cannulated screws for femoral neck fracture fixation in small-breed dogs show promise in cadaveric study.

OBJECTIVE: To biomechanically evaluate the stability of internal fixation methods for femoral neck fractures in small-breed dogs. Furthermore, the possibility of replacing the headed screw with fully threaded headless cannulated screws in the fixation method was assessed. METHODS: The study was conducted from December 12, 2023, to February 7, 2024. A total of 18 femurs from 9 canine cadavers were used in this study. After a simple neck fracture was created, in group A (n = 6), the fracture was stabilized with three 1.1-mm parallel Kirschner wires (K-wires). In group B (n = 6), a 3.0-mm partially threaded cannulated screw and an antirotation pin were used. In group C (n = 6), a 2.5-mm fully threaded headless cannulated screw and an antirotation pin were used. A mechanical test was conducted to apply a single axial compressive load to the femoral head. RESULTS: 9 adult small-breed dogs weighing 3.6 to 8.3 kg (mean ± SD; 5.9 ± 1.6). The mean maximum failure load was highest in group C (495 ± 81 N), followed by group B (454 ± 50.4 N), and then group A (222 ± 21.6 N). Significant differences in maximum failure load were observed between groups A and B as well as groups A and C but not between groups B and C. CONCLUSION: The use of fully threaded headless cannulated screws presents a promising method for internal fixation of canine femoral neck fractures. CLINICAL RELEVANCE: To demonstrate the potential stability and reliability of fully threaded headless cannulated screws.

Virtual surgical planning and use of a 3D-printed, patient-specific reduction system for minimally invasive plate osteosynthesis of diaphyseal tibial fractures in dogs: A historic case control study.

OBJECTIVE: To compare the efficacy and clinical outcomes of computed tomography (CT)-based virtual surgical planning (VSP) and a three-dimensional (3D)-printed, patient-specific reduction system to conventional indirect reduction techniques for diaphyseal tibial fractures stabilized using minimally invasive plate osteosynthesis (MIPO) in dogs. STUDY DESIGN: A prospective clinical study with a historic control cohort. SAMPLE POPULATION: Dogs undergoing MIPO stabilization of diaphyseal tibial fractures using a custom 3D-printed reduction system (3D-MIPO; n = 15) or conventional indirect reduction techniques (c-MIPO; n = 14). METHODS: Dogs were prospectively enrolled to the 3D-MIPO group and CT scans were used to design and fabricate a custom 3D-printed reduction system to facilitate MIPO. Medical records were searched to identify dogs for the c-MIPO group. Pre-, intra- and postoperative parameters were compared between groups. RESULTS: The duration from presentation until surgery was 23 h longer in the 3D-MIPO group (p = .002). Fewer intraoperative fluoroscopic images were acquired (p < .001) and mean surgical duration was 34 min shorter in the 3D-MIPO group (p = .014). Median postoperative tibial length, frontal alignment, and sagittal alignment were within 4 mm, 3° and 3°, respectively, of the contralateral tibia in both groups and did not differ between reduction groups (p > .1). Postoperative complications occurred in 27% and 14% of fractures in the 3D-MIPO and c-MIPO groups, respectively. CONCLUSION: Both reduction methods yielded comparable results. Although the preoperative planning and guide preparation was time consuming, surgery times were shorter and fluoroscopy use was less in the 3D-MIPO group. CLINICAL SIGNIFICANCE: VSP and the custom 3D-printed reduction system facilitated efficient MIPO.

An Accessible Nephrectomy and Cystotomy Simulator for Use in Teaching Small Animal Surgery.

The use of simulators in veterinary education has been increasing over the last few years. This is fundamental for surgical classes, as simulators can provide a better learning environment for the students. Two procedures commonly taught in veterinary surgical practical classes are nephrectomy and cystotomy. However, the lack of simulators for use in these classes limits the training options to the use of cadavers, which have a number of associated disadvantages, including the potential for autolysis. The aim of this study was to develop and assess the value of a simple nephrectomy and cystotomy simulator that could replace the use of cadavers in surgical practical classes. The simulator, which represented the abdominal cavity, bladder, kidneys, ureter, vessels and adipose tissue, was constructed by using synthetic materials. To evaluate its usefulness and acceptance by the students, the learning outcomes and student satisfaction, for both the simulator and an ethically sourced dog cadaver, were compared. The students completed a Likert scale questionnaire, and the answers were evaluated by using the Diagnostic Content Validation (DCV) model. The simulator was well accepted by the students, with the best scores achieved for the ureter divulsion and ligation procedures; good results were also recorded for the kidney vessel ligature and urinary bladder suture practice. The scores showed that the simulator provided an acceptable experience during the training process and increased the confidence of the students in performing the procedure.

Greater ischiatic notch plane versus parasacral block in dogs undergoing pelvic limb surgery: a retrospective noninferiority cohort study on perioperative opioid consumption.

OBJECTIVE: To compare perioperative opioid consumption in dogs undergoing pelvic limb surgeries and receiving a lumbosacral plexus block by combining a lumbar [lateral pre-iliac (LPI)] block with a lumbosacral trunk [i.e. parasacral (PS group) or greater ischiatic notch plane (GIN group)] block. Study design Retrospective, descriptive, exploratory, noninferiority cohort study. METHODS: Medical records of 37 client-owned dogs were analyzed. Intraoperative (primary outcome) and postoperative (24 hours) opioid use, 24 hour cumulative pain scores and prevalence of complications were compared between the two groups. Opioid use was quantified in morphine equivalents (ME, mg kg-1 ). The noninferiority limit for intraoperative opioid consumption was set at 0.05 ME kg-1 hour-1. Demographic data, procedure duration, surgery type and perioperative dexmedetomidine and ketamine use were also collected. A t-test or Wilcoxon rank-sum test, a Fisher's exact test and multivariable linear regression were used. Significance was set at p < 0.05. RESULTS: The GIN and PS groups comprised 17 and 20 dogs, respectively. Total intraoperative ME consumption was 0.17 (0.11-0.21) and 0.22 (0.16-0.30) mg kg-1 hour-1 for the GIN and PS groups, respectively (p = 0.077). The noninferiority analysis adjusted by surgery type and body mass revealed that the mean difference between the groups (GIN - PS) was -0.039 (95% CI -0.11-0.03, p = 0.247) ME mg kg-1 hour-1, indicating that the GIN group was not inferior to the PS group regarding intraoperative ME consumption. Dexmedetomidine and ketamine use, postoperative ME consumption and pain scores were similar between groups. CONCLUSIONS AND CLINICAL RELEVANCE: This retrospective study and preliminary observations support the clinical use of the GIN plane block, demonstrating its noninferiority to the PS block when combined with the LPI block for multimodal perioperative analgesia in dogs undergoing pelvic limb surgeries.

Unlocking perspectives on surgical sterilization in dogs and cats: A comprehensive study among Thai veterinary professionals.

Gaining insights into the opinions and attitudes of veterinarians is essential for enhancing the sterilization rate, given their influential role in guiding pet owners. This study investigated the attitudes and practices of Thai veterinarians concerning surgical sterilization in dogs and cats. The survey was conducted from August 2022 to December 2022 and distributed through online and on-site questionnaires across all regions of Thailand. Seven hundred twenty-four veterinarians participated. A strong inclination toward sterilization for population control with a notable preference for female animals was revealed. The factors related to the necessity of sterilization in the opinion of Thai veterinarians were gender, age of veterinarians, and animal sex (P<0.05). Male veterinarians tended to assign less importance to sterilization, especially for male dogs (OR = 0.824), compared to their female counterparts. Older veterinarians tended to prioritize sterilization less than younger ones (OR = 0.985). Regarding animal's sex, a preference for sterilizing females over males in both dogs and cats (OR = 0.291) was observed. Encouraging sterilization should be promoted equally among veterinarians of both genders, with particular emphasis on older male veterinary practitioners. Most veterinarians recommended sterilization between 4 and 6 months for female cats and 7-10 months for male cats, male dogs and female dogs. Overall, mean agreement scores for prepubertal gonadectomy were significantly higher (P<0.05) for female dogs and cats, and the only significant factor associated with these scores was the animal's sex. Veterinarians expressed more disagreement with prepubertal sterilization in males compared to females, with an OR of 0.33. There were some concerns in prepubertal sterilization such as growth and development problems, anesthesia risks, and urinary tract disorders. These insights observed in Thailand hold potential implications for other countries facing similar challenges in effectively managing pet overpopulation.

Anastomosis of the caudal thoracic duct and intercostal vein using a microvascular anastomotic coupler device: Experimental study in six dogs.

OBJECTIVE: To describe the technique for anastomosis of the caudal thoracic duct (TD) to the 10th or 11th intercostal vein (ICV) using a microvascular anastomotic coupler (MAC) device in dogs and assess patency of the anastomosis on days 0 and 30. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Six adult Beagle dogs. METHODS: Under general anesthesia, fluoroscopic popliteal lymphangiography was performed and the TD identified. A right ninth or 10th intercostal thoracotomy was performed. Using an operating microscope, the TD and the 10th or 11th ICV were isolated, ligated, and anastomosed using a 1.5 or 2.0 mm MAC. Fluoroscopic popliteal lymphangiography was repeated immediately after surgery and on day 30. RESULTS: The anastomosis was successful and lymphangiography documented flow into the azygos vein in all six dogs immediately after surgery. At day 30, the anastomosis was patent in four of six dogs. In two dogs, flow through the anastomosis was obstructed due to kinking of the ICV just cranial to the MAC. CONCLUSION: Anastomosis of the TD and ICV using a MAC was feasible and was shown to maintain patency up to 30 days. When performing the anastomosis, care should be taken to ensure the ICV is not kinked by the MAC. CLINICAL SIGNIFICANCE: Direct anastomosis of the TD and ICV may have application for treatment of idiopathic chylothorax in dogs by maintaining flow from the abdominal lymphatics to the central venous circulation and thereby preventing the stimulus for collateral circulation and persistent chylous effusion. Further investigation is warranted to assess the efficacy of this technique in dogs affected with idiopathic chylothorax.

Mechanical comparison of straight and pre-bent interlocking nails used for the stabilization of a tibial gap fracture model.

OBJECTIVE: To compare the mechanical behavior of straight (STRT) and pre-bent (BENT) I-Loc angle-stable interlocking nails (AS-ILN) used for stabilization of canine mid-diaphyseal tibial fractures. STUDY DESIGN: In vitro experimental study. SAMPLE POPULATION: Tibial gap fracture models (n = 5/group). METHODS: Tibial models simulating a comminuted mid-diaphyseal fracture were stabilized with either a STRT or BENT I-Loc AS-ILN. Bent nails were contoured to match the 10° tibial recurvatum of a mid-size dog. Constructs were subjected to cyclic eccentric compressive loads followed by ramp load until failure. Construct compliance, maximum compressive load and resistive torque, yield load and angular deformation at 450 N were statistically compared using t-tests (p < .05). Failure modes were described. RESULTS: Compliance was 45% lower in BENT than STRT groups (p < .0001). Constructs in the BENT group sustained ~20% and 34% greater maximum and yield loads, respectively, than STRT constructs. Maximum resistive torques were similar between groups (p = .16). At 450 N, sagittal plane angular deformation increased from 0° to 4° in procurvatum (STRT group) and decreased from 10° to 8° in recurvatum (BENT group-p < .0001). Construct yield failure occurred at the nail isthmus in both groups. CONCLUSION: These results demonstrated that, in a tibial gap fracture model, pre-bending I-Loc AS-ILNs provided mechanical advantages by increasing their ability to resist bending resulting from eccentric compressive loads. CLINICAL SIGNIFICANCE: Pre-bending may reduce the occurrence of tibial nail yield failure. Surgeons should therefore consider pre-bending tibial I-Loc nails to match the bone anatomical recurvatum prior to implantation.

Effect of surgery on oxidative stress and endogenous tocopherol concentrations in juvenile female dogs.

BACKGROUND: Surgery such as ovariectomy causes an inflammatory and oxidative stress. This study was designed to evaluate endogenous tocopherol levels in response to surgical oxidative stress induced by abdominal surgery (ovariectomy) in thirty-two juvenile female dogs. The dogs received meloxicam before surgery (0.2 mg/kg SC) and after surgery (0.1 mg/kg OS every 24 h), 0.03 mg/kg of atropine sulfate (IM), and propofol 4 mg/kg intravenously (IV). General anesthesia was maintained with sevoflurane. Physiological, hematological and biochemical parameters, malondialdehyde (MDA) and α-, δ-, γ-tocopherols were evaluated at baseline, 36 and 48 h after surgery. RESULTS: The physiological parameters remained within normal ranges. Blood glucose concentration increased, while the albumin levels decreased after surgery. Rescue analgesia was not required. MDA levels increased above the baseline at 36 and 48 h after surgery (P < 0.001). The α-, δ-, and γ-tocopherol concentrations decreased from baseline at 36 and 48 h after surgery (P < 0.001). CONCLUSIONS: Surgery in juvenile female dogs revealed oxidative, increased MDA concentrations, reduced tocopherol levels, and had a clinically insignificant influence on homeostasis.

Laparotomy-assisted endoscopic removal of gastrointestinal foreign bodies: Evaluation of this technique and postoperative recovery in dogs and cats.

OBJECTIVE: To compare the outcome of the laparotomy-assisted endoscopic removal (LAER) of gastrointestinal foreign bodies (FBs) with traditional enterotomy, and to determine which factors affected the ability to remove FBs. STUDY DESIGN: Retrospective observational study. SAMPLE POPULATION: Dogs and cats (n = 81) with gastrointestinal FBs. METHODS: Dogs and cats were divided into Group 1 (LAER, n = 40) and Group 2 (Enterotomy, n = 41). The localization and characteristics of the FBs (sharp or blunt; discrete or linear; single or multiple) were evaluated statistically to identify the factors that affected the ability of LAER to remove, partially or completely, the FBs (χ2 test). The length of the postoperative stay, postoperative analgesia, and resumption of spontaneous feeding were compared between groups (Mann-Whitney U-test). Short-term follow up (14 days) was recorded. RESULTS: Laparotomy-assisted endoscopic removal allowed complete or partial removal of FBs in 35/40 dogs and cats, regardless of the characteristics or the localization of the FBs. The presence of intestinal wall damage (p = .043) was associated with the conversion to an enterotomy. Group 1 required a shorter postoperative hospital stay (p = .006), less need for analgesia (p < .001), and experienced a faster resumption of spontaneous feeding (p = .012), and similar complication rate to Group 2. CONCLUSION: Laparotomy-assisted endoscopic removal resulted in a faster postoperative recovery when compared with an enterotomy. The FBs' characteristics or localization did not affect the efficacy of the technique to remove FBs. CLINICAL SIGNIFICANCE: Laparotomy-assisted endoscopic removal allows the removal of a variety of FBs, avoiding intestinal incision and resulting in a fast postoperative recovery.

Feasibility of open cholangioscopy with disposable flexible endoscopes.

OBJECTIVE: To determine the feasibility of open cholangioscopy using disposable flexible endoscopes in canine cadavers and describe the surgical approach. STUDY DESIGN: Ex vivo experimental cadaveric study. SAMPLE POPULATION: Eight canine cadavers. METHODS: Cadavers ranging from 5.8 to 43.8 kg underwent open transcholecystic cholangioscopy using a disposable flexible endoscope with a 3.8 mm outer diameter and 1.2 mm working channel and the surgical approach was described. The most distal anatomical region of the biliary tree towards the duodenal papilla that was visualized with the endoscope was recorded in each cadaver. A 2.7 mm rigid endoscope and a 1.9 mm flexible endoscope were also trialed and findings recorded. Endoscopic tools were trialed and their usage recorded. RESULTS: The disposable flexible endoscope was feasible for visualization of the junction of the common bile duct, cystic duct, and hepatic ducts in all eight dogs. Cholangioscopy using a 2.7 mm rigid endoscope did not provide further distal visualization. The 1.9 mm flexible endoscope was able to traverse down to the level of the major duodenal papilla in a 43.8 kg cadaver. Use of certain endoscopic tools can be considered through the disposable flexible endoscope although fluid instillation was affected. CONCLUSION: A 3.8 mm disposable flexible endoscope could be placed through an open transcholecystic approach to provide intraluminal endoscopic evaluation up to the level of the junction of the common bile duct, cystic duct, and hepatic ducts in dogs without cholecystic disease. CLINICAL SIGNIFICANCE: Open transcholecystic cholangioscopy with a disposable flexible endoscope could provide a low-cost diagnostic and therapeutic tool in cases of obstructive biliary disease up to the level of the common bile duct.

Impact of arthroscopy on post-procedure intra-articular elbow injections: A cadaveric study.

OBJECTIVE: To determine the influence of arthroscopy and injection volume on post-procedure intra-articular (IA) injection extravasation. STUDY DESIGN: Ex vivo prospective study. SAMPLE POPULATION: A total of 40 paired canine cadaver forelimbs. METHODS: After radiographs and computed tomography (CT) scans with three-dimensional (3D) digital bone model reconstructions, elbows were randomly assigned to the arthroscopy or control group and randomly assigned to receive an IA injection of 2 or 4 mL of contrast. Elbow arthroscopy was performed on assigned specimens, followed by IA injections of contrast in all elbows, and imaging was repeated. 3D digital model volumes were compared. Images were interpreted and scored for extravasation by a radiologist unaware of treatment and volume assignments. RESULTS: Based on CT images and regardless of treatment group, IA injections of 4 mL resulted in a mean extravasation score of 2.25 (SD 0.97) versus 1.55 (SD 1.05) (p = .02) for 2 mL IA injections. The change in 3D model volumes after IA injections was a mean of 13.2 cm3 (SD 5.85) after 4 mL injections, compared to 6.97 cm3 (SD 6.28) (p = .003) after 2 mL injections. On radiographic evaluation, but not CT, the mean extravasation scores were 2.45 (SD 1.15) for the arthroscopy group and 1.25 (SD 0.79) for the control group (p < .001). CONCLUSION: A larger volume of IA injection resulted in higher CT extravasation scores and larger 3D volumes regardless of arthroscopic treatment. CLINICAL SIGNIFICANCE: IA injections performed immediately after arthroscopy resulted in 50% or less extravasation, especially with a smaller IA injection volume.

Efficacy of virtual surgical planning and a three-dimensional-printed, patient-specific reduction system to facilitate alignment of diaphyseal tibial fractures stabilized by minimally invasive plate osteosynthesis in dogs: A prospective clinical study.

OBJECTIVE: To evaluate the efficacy of a three-dimensional (3D)-printed, patient-specific reduction system for aligning diaphyseal tibial fractures stabilized using minimally invasive plate osteosynthesis (MIPO). STUDY DESIGN: Prospective clinical trial. SAMPLE POPULATION: Fifteen client owned dogs. METHODS: Virtual 3D models of both pelvic limbs were created. Pin guides were designed to conform to the proximal and distal tibia. A reduction bridge was designed to align the pin guides based on the guides' spatial location. Guides were 3D printed, sterilized, and applied, in conjunction with transient application of a circular fixator, to facilitate indirect fracture realignment before plate application. Alignment of the stabilized tibiae was assessed using postoperative computed tomography scans. RESULTS: Mean duration required for virtual planning was 2.5 h and a mean of 50.7 h elapsed between presentation and surgery. Guide placement was accurate with minor median discrepancies in translation and frontal, sagittal, and axial plane positioning of 2.9 mm, 3.6°, 2.7°, and 6.8°, respectively. Application of the reduction system restored mean tibial length and frontal, sagittal, and axial alignment within 1.7 mm, 1.9°, 1.7°, and 4.5°, respectively, of the contralateral tibia. CONCLUSION: Design and fabrication of a 3D-printed, patient-specific fracture reduction system is feasible in a relevant clinical timeline. Intraoperative pin-guide placement was reasonably accurate with minor discrepancies compared to the virtual plan. Custom 3D-printed reduction system application facilitated near-anatomic or acceptable fracture reduction in all dogs. CLINICAL SIGNIFICANCE: Virtual planning and fabrication of a 3D-printing patient-specific fracture reduction system is practical and facilitated acceptable, if not near-anatomic, fracture alignment during MIPO.

A lateral approach allows accurate and stable total elbow replacement in dogs.

OBJECTIVE: Evaluate whether total elbow replacement (TER) through a lateral approach is accurate and stable. ANIMALS: 12 skeletally mature large-breed dog cadavers were used. METHODS: Limb alignment, elbow joint motion, and collateral ligament laxity were evaluated preoperatively. The order of surgery (left or right) and the approach (lateral or medial) were randomly selected for TER in each dog. The other approach was used in the contralateral elbow. Intraoperative technical difficulties, duration of surgery, and anatomic complications were recorded. Limb alignment, elbow joint motion, collateral ligament laxity, and prosthetic component alignment were evaluated after surgery. Data were collected from June 11 to 15, 2023. RESULTS: The duration of surgery using a lateral or medial approach did not differ (P = .499). Anatomic complications were not observed. The lateral approach resulted in 8° more elbow extension (P = .003), 1.58° less lateral collateral ligament constraint (P = .033), 2.80° less medial collateral ligament constraint (P = .002), 4.38° less frontal plane constraint (P = .004), 8° greater humeral component inclination (P = .033), and 5.6° greater radioulnar component varus (P = .001) than the medial approach. Varus of the radius, mechanical axis deviation, limb supination, elbow flexion, mediolateral humeral component and craniocaudal radioulnar component orientation did not differ among joints operated using a lateral or medial approach. In normal cadaveric elbows, a lateral approach for TER appears feasible, producing equivalent limb alignment, joint laxity, and joint motion to normal elbows and to TER placed using a medial approach. CLINICAL RELEVANCE: In dogs, TER can be performed using a lateral surgical approach.

Effect of tibial plateau angle < 5° on ground reaction forces in dogs treated with tibial plateau leveling osteotomy for cranial cruciate ligament rupture up to 6 months postoperatively.

Tibial plateau leveling osteotomy (TPLO) has been commonly performed in dogs with cranial cruciate ligament disease (CCLD) since the introduction by Slocum and Slocum (1993). To reduce cranial tibial thrust the TPLO technique aims for a postoperative tibial plateau angle (TPA) of 5-6.5°. In recent years studies have shown that a postoperative TPA below 5° could be beneficial regarding stifle stability or meniscal load. Dogs with CCLD that were treated with TPLO, were examined preoperatively, six weeks, three and six months postoperatively with gait analysis and grouped according to their postoperative TPA. The aims of study was (1) to evaluate if dogs with a postoperative TPA below 5° would have a faster limb function recovery up to six months postoperatively as measured objectively with ground reaction forces (GRFs) and (2) to determine whether the postoperative TPA correlates with the outcome measurements. Dogs with TPA <5° showed no faster limb function recovery postoperatively up to six months as measured with peak vertical force (PVF) or vertical impulse (VI) (p > 0.05). No correlation for the postoperative TPA <5° on GRFs was demonstrated. But the postoperative TPA showed a significant correlation with the symmetry indices of PVF (SIPVF) and VI (SIVI) for all dogs (>5° and <5° TPA together), indicating that with lower postoperative TPA dogs had a more symmetrical gait in hindlimbs SIPVF (r = 0.144, p < 0.05) and SIVI (r = 0.189, p < 0.01). The study indicates that a lower postoperative TPA could be beneficial regarding hindlimb symmetry indices of GRFs.

The impact of surgery resident training on the duration of tibial plateau leveling osteotomy surgery.

OBJECTIVE: To investigate the impact of surgery resident training on surgery duration in tibial plateau leveling osteotomy (TPLO) and evaluate whether surgery duration differs with each year of residency training. STUDY DESIGN: Retrospective medical record review. ANIMALS: A total of 256 client-owned dogs underwent TPLO. METHODS: Records of dogs that underwent TPLO between August 2019 and August 2022 were reviewed. The effects of the surgeon (faculty/resident) and the procedure (arthrotomy/arthroscopy) on TPLO surgery duration were examined with an analysis of variance, and geometric least squares means (GLSM) were compared. A linear mixed effects model (LMM) was fitted to quantify fixed and random effects. RESULTS: Four faculty surgeons performed 74 (29%) TPLOs, while 10 residents performed 182 (71%) TPLOs under the direct supervision of a faculty surgeon. All TPLOs were conducted with arthrotomy (109; 43%) or arthroscopy (147; 57%). Overall, residents (GLSM, 153 min) required 54% more surgery duration than faculty surgeons (GLSM, 99 min). Surgery duration among first-year residents (GLSM, 170 min) was 15% longer than second- (GLSM, 148 min) and third-year (GLSM, 147 min) residents, whereas the duration did not differ statistically between second- and third-year residents. Arthroscopy, meniscal tear treatment, surgery on the right stifle, and increasing patient weight were also associated with longer surgery duration. CONCLUSION: The duration of TPLO surgery significantly decreased after the first year of residency, but did not decrease afterward. CLINICAL SIGNIFICANCE: The results will aid with resource allocation, curricula planning, and cost management associated with resident training.

Influence of intravenous fentanyl or dexmedetomidine infusions, combined with lidocaine and ketamine, on cardiovascular response, sevoflurane requirement and postoperative pain in dogs anesthetized for unilateral mastectomy.

OBJECTIVE: To compare the effects of constant rate infusions (CRI) of fentanyl or dexmedetomidine, combined with lidocaine and ketamine, on cardiovascular response during surgery, sevoflurane requirement and postoperative pain in dogs undergoing mastectomy. STUDY DESIGN: Prospective, randomized, blinded, clinical trial. ANIMALS: A total of 29 female dogs with mammary tumors. METHODS: Premedication consisted of intramuscular acepromazine and morphine. General anesthesia was induced with intravenous propofol and maintained with sevoflurane. Dogs were randomized to be administered intravenous DLK [dexmedetomidine 1 µg kg-1 loading dose (LD) and 1 µg kg-1 hour-1; lidocaine 2 mg kg-1 LD and 3 mg kg-1 hour-1; ketamine 1 mg kg-1 LD and 0.6 mg kg-1 hour-1; n = 14] or FLK (fentanyl 5 µg kg-1 LD and 9 µg kg-1 hour-1; same doses of lidocaine and ketamine; n = 15) during anesthesia. Cardiorespiratory variables and end-tidal sevoflurane (Fe'Sevo) were recorded during surgery. The number of dogs administered ephedrine to treat arterial hypotension [mean arterial pressure (MAP) < 60 mmHg] was recorded. Meloxicam was administered to both groups. Postoperative pain and rescue analgesia requirement were assessed for 24 hours using the short form of the Glasgow Composite Measure Pain Scale. Data were compared using a mixed effects model or a Mann-Whitney test. RESULTS: More dogs required ephedrine in FLK than in DLK (67% versus 7%). Heart rate was not significantly different between groups, whereas lower values of MAP (p ≤ 0.01) and Fe'Sevo (p = 0.018) were observed in FLK than in DLK. Rescue analgesia was administered to 2/15 dogs in FLK and 0/14 dogs in DLK. CONCLUSIONS AND CLINICAL RELEVANCE: Based on the cardiovascular response during surgery, intraoperative infusions of FLK and DLK provided adequate antinociception. Infusion of DLK provided greater stability of blood pressure. Both protocols resulted in minimal need for additional analgesia within 24 hours postoperatively.

Quasi-static mechanical evaluation of canine cementless total hip replacement broaches: effect of tooth design on broach and stem insertion.

BACKGROUND: Biomedtrix BFX® cementless total hip replacement (THR) requires the use of femoral broaches to prepare a press-fit envelope within the femur for subsequent stem insertion. Current broaches contain teeth that crush and remove cancellous bone; however, they are not particularly well-suited for broaching sclerotic (corticalized) cancellous bone. In this study, three tooth designs [Control, TG1 (additional V-grooves), TG2 (diamond tooth pattern)] were evaluated with a quasi-static testing protocol and polyurethane test blocks simulating normal and sclerotic bone. To mimic clinical broaching, a series of five sequential broach insertions were used to determine cumulative broaching energy (J) and peak loads during broach insertion. To determine the effect of broach tooth design on THR stem insertion, a BFX® stem was inserted into prepared test blocks and insertion and subsidence energy and peak loads were determined. RESULTS: Broach tooth design led to significant differences in broaching energy and peak broaching loads in test blocks of both densities. In low density test blocks, TG1 required the lowest cumulative broaching energy (10.76 ±0.29 J), followed by Control (12.18 ±1.20 J) and TG2 (16.66 ±0.78 J) broaches. In high density test blocks, TG1 required the lowest cumulative broaching energy (32.60 ±2.54 J) as compared to Control (33.25 ±2.16 J) and TG2 (59.97 ±3.07 J).  During stem insertion and subsidence testing, stem insertion energy for high density test blocks prepared with Control broaches was 14.53 ± 0.81 J, which was significantly lower than blocks prepared with TG1 (22.53 ± 1.04 J) or TG2 (19.38 ± 3.00 J) broaches. For stem subsidence testing in high density blocks, TG1 prepared blocks required the highest amount of energy to undergo subsidence (14.49 ± 0.49 J), which was significantly greater than test blocks prepared with Control (11.09 ±0.09 J) or TG2 (12.57 ± 0.81 J) broaches. CONCLUSIONS: The additional V-grooves in TG1 broaches demonstrated improved broaching performance while also generating press-fit envelopes that were more resistant to stem insertion and subsidence. TG1 broaches may prove useful in the clinical setting; however additional studies that more closely simulate clinical broach impaction are necessary prior to making widespread changes to THR broaches.