Prevalence of radiographic appendicular osteoarthritis and associated clinical signs in young dogs.

This study aimed to determine the prevalence of osteoarthritis (OA) and associated clinical signs in young dogs. Owners of dogs aged 8 months-4 years from a single practice, were contacted in random order, to participate in a general health screen. Clinical and orthopedic examinations were performed. Each joint was scored for pain reactions (0-4). Orthogonal radiographs of all joints were made under sedation. Each joint was scored for radiographic OA (rOA) severity on an 11-point scale. Clinical OA (cOA) was defined as an overlap of rOA and joint pain in ≥ 1 joint. Owners completed OA questionnaires. The owners of 123 dogs agreed to participate. Overall, 39.8% (49/123) of dogs had rOA in ≥ 1 joint, and 16.3% (20/123) or 23.6% (29/123) dogs had cOA, depending on the cut-off value of joint pain; moderate (2), or mild (1), respectively. Owners of dogs with cOA observed signs of impairment in approximately 30% of cases. Only 2 dogs with cOA were receiving OA pain management. The most commonly affected joints in descending order of frequency were elbow, hip, tarsus, and stifle. Radiographically visible OA is common in young dogs, and 40-60% of dogs with rOA had cOA. However, OA-pain appears underdiagnosed and undertreated in young dogs.

A systematic review of oncological outcomes after nipple-sparing mastectomy for breast cancer.

Nipple-sparing mastectomy is an alternative to skin-sparing mastectomy in select patients. Increasing evidence supports its use in the setting of breast cancer, however concerns still exist regarding oncological safety. The aim of this systematic review was to evaluate long-term oncological outcomes of patients who underwent nipple-sparing mastectomy for breast cancer. A systematic review of the literature was performed to evaluate oncological outcomes in patients with breast cancer who underwent nipple-sparing mastectomy. Five major databases (PubMed, Embase, Scopus, Web of Science and Cochrane) were searched. The review included all original articles published in English reporting long-term oncological outcomes. 2334 studies were identified. After applying inclusion and exclusion criteria, 17 retrospective studies involving 7107 patients were included. The indication for nipple-sparing mastectomy was invasive carcinoma in 6069 patients (85.4%) and in situ disease in 1038 (14.6%). Median follow up was 48 months (range 25-94). The weighted mean rates of local recurrence and recurrence involving the nipple-areola complex were 5.4% (0.9-11.9) and 1.3% (0-4.9), respectively. The weighted mean distant failure rate was 4.8% (1.5-23.0). Therapeutic nipple-sparing mastectomy is oncologically safe in select patients with breast cancer.

Real-Time Feedback to Enhance the Teaching of Wire Tying.

Teaching the art of wire tying is difficult because the instructor is not able to gauge the effectiveness of the final product. The impact of an incorrect technique is usually not evident. Also, the instructor does not have a way to demonstrate the different levels of tension generated by different wire knotting techniques, nor their differing abilities to resist a load that a patient may apply. In this paper, a device is described that can provide real-time feedback on wire tension generated during knot tying, and how particular knots resist an applied distraction. This device has been used to deliver a live demonstration to reinforce lecture material, and in small group teaching exercises, where real-time feedback enhances skills and understanding. A stepwise training schedule for surgery residents structured as an entrustable professional activity is proposed.

Double-loop cerclage resists greater loads for more cycles than twist and single-loop cerclage.

OBJECTIVE: To compare the mechanical performance of cerclage secured with twist, single-loop, and double-loop knots subjected to cyclic loading. STUDY DESIGN: In vitro biomechanical study. SAMPLE POPULATION: Twist, single-loop and double-loop cerclage configurations of 1.0 mm wire. METHODS: The peak load resisted by each cerclage type was determined (n = 6). Cerclage were loaded cyclically to 80%, 60%, 40%, or 20% of its peak load (n = 8 per load level). The number of cycles until each cerclage loosened (residual tension <10 N) was recorded. RESULTS: All wires that failed did so by loosening. Twist cerclage cycled to 390 N and 290 N loosened within the first 10 cycles, and, when cycled to 100 N, they loosened by 250 cycles. All twist knots loosened by untwisting. Single-loop cerclage cycled to 320 N loosened within 10 cycles. At 240 N, 5 single-loop cerclage resisted 250 cycles before loosening. At 160 N, 2 of the 8 single-loop cerclage did not loosen by 100 000 cycles. When cycled to 640 N, one of the double-loop cerclage did not loosen following 500 000 cycles. When cycled to 480 N, 3 of the 8 wires did not loosen. CONCLUSION: Double-loop cerclage will be tighter and are better able to resist cycling than twist or single-loop cerclage. CLINICAL SIGNIFICANCE: Use of double-loop cerclage to stabilize bone fragments or prevent fissure propagation can be expected to provide greater resistance to loosening than twist or single-loop cerclage, both initially and with repeated loading.

Defining the rate of, and factors influencing, radiographic progression of osteoarthritis of the canine hip joint.

BACKGROUND: This study aimed to define the rate of progression of radiographic osteoarthritis (OA) of the canine hip joint and to describe factors affecting this progression. METHODS: Dogs that underwent unilateral total hip replacement (THR) were reviewed for the evaluation of radiographic appearance of the non-operated hip joint over time. Standard extended ventrodorsal hip radiographs were taken preoperatively and postoperatively. All images were anonymized, randomized and scored using three different methods. The mean daily change between evaluations was calculated in each individual dog, and the effect of sex, age, body weight, open/closed status of the proximal femoral physis, preoperative severity of OA, time after surgery and their interactions, were investigated as potential influencing factors. RESULTS: After reviewing the medical records, 163 dogs (468 images) met the inclusion criteria. Consistent across the three scoring systems, radiographic progression of OA was greater in younger (open physis) and spayed female dogs. A subset of seven patients (4.3%) had a faster progression of OA and was considered outliers. No dog was rated as outlier by all three scoring systems. CONCLUSION: The rate of progression of radiographically assessed coxofemoral OA varies greatly, but is faster in younger, spayed female dogs. Unusually fast progression occasionally occurs.

Use of Top Hat Audience Response Software in a Third-Year Veterinary Medicine and Surgery Course.

Audience response devices are useful tools that can improve student engagement and learning during instructional sessions. The purpose of this article is to describe our experience with a new cloud-based application known as Top Hat, which includes audience response tools in its application suite. The software was used in a multi-specialty, multi-instructor medicine and surgery course in the third year of a veterinary curriculum. In addition to standard multiple-choice and short-answer questions, Top Hat has several unique question types and methods of displaying the responses given. These include displaying free-text responses in a word cloud format and a "click-on-target" question type that allows students to indicate their response by clicking on a location within an image. Responses for this latter question type are displayed in a heat map format. A discussion tool is also available, which allows students to respond, read other students' responses in real time, and then reply again if warranted. This feature also supports drawing-based responses. The variety of question types was very useful in keeping students engaged during teaching sessions, giving this application several advantages over systems that are limited to multiple-choice questions only. In addition, the application allowed rapid identification of areas of student knowledge and misunderstandings, which facilitated the direction of further discussion and clarification of important learning issues.

Influence of wire configuration on resistance to fragment distraction of tension bands placed in a greater trochanteric osteotomy model.

OBJECTIVE: To determine the influence of wiring configurations on initial tension and resistance to tensile loads in tension band constructs without the contributions of Kirschner-wire stabilization. STUDY DESIGN: Experimental study. SAMPLE POPULATION: A solid brass femur model manufactured on the basis of computed tomography of a normal right femur of a 30-kg dog modified by transection of the greater trochanter and placement of two pins that did not cross the simulated osteotomy. METHODS: Four tension band configurations were applied to the metal trochanteric osteotomy model: figure-of-eight with one twist (OT), figure-of-eight with two twists (TT), dual interlocking single loop, and double loop (DL). Configurations were tested under both monotonic loading (n = 8 per configuration) and incremental cyclic loading (n = 8 per configuration). Initial tension after tying, residual tension remaining after each cycle, and failure load at 2 mm of displacement (considered equivalent to clinical failure) were compared between configurations. RESULTS: The initial tension and the load to 2 mm of displacement were lower for OT wires compared with TT wires. The DL was the strongest and most stable configuration, generating 2.3 to 3.5 times greater initial tension, maintaining a greater percentage of residual tension under incremental cyclic loads, and resisting 2.0 to 2.4 times greater load before failure at 2 mm. Failure load was highly correlated with initial tension. CONCLUSION: Wire configurations reaching greater initial tension, such as the DL, allowed constructs to resist higher tensile loads. CLINICAL IMPACT: Wire configurations allowing higher initial tension may be warranted when tension bands are expected to sustain high tensile loads.

Biomechanics of Fracture Fixation.

This article reviews the biomechanical parameters of fracture repair that influence construct stiffness and strength. The stiffness influences the relative motion between fracture fragments, known as gap strain, and, thus, callus development. Construct strength determines the magnitude and number of load events that the repair can resist before failure. Surgeons must optimize these parameters in order to achieve satisfactory outcomes for the patients.

Influence of Radiographic Positioning on Canine Sacroiliac and Lumbosacral Angle Measurements.

OBJECTIVES: To evaluate the influence of radiographic malpositioning on canine sacroiliac and lumbosacral inclination angles. METHODS: Using canine cadavers, lateral pelvic radiographs were acquired with the radiographic beam in a neutral position and then rotated 5, 10 and 15° to mimic rotational malpositioning. The focal point of the beam was then focused over the abdomen and again over mid-diaphysis of the femur to mimic an abdominal or femoral radiographic study. RESULTS: Five degrees of rotational malpositioning did not influence measurements of sacroiliac or lumbosacral inclination, but malpositioning by more than 5° led to a significant decrease in both sacroiliac and lumbosacral angles. Moving the focal point to the femur significantly decreased the measured lumbosacral angle. Abdominally centred radiographs had no effect on lumbosacral and sacroiliac angle measurements. CLINICAL SIGNIFICANCE: When evaluating canine lumbosacral and sacroiliac angles radiographically, pelvic rotation of more than 5° should be avoided as should the use of lateral radiographs centred over the femur.

Repeatability and accuracy testing of a weight distribution platform and comparison to a pressure sensitive walkway to assess static weight distribution.

OBJECTIVE: To evaluate the accuracy and repeatability of measurements collected using a weight distribution platform and a pressure sensitive walkway using an inanimate object with known weight distribution. METHODS: A custom-built jig with a range of weights was applied in a random order. Measurements were collected on both devices and compared to each other and to the known weight distribution. RESULTS: Weight distribution platform and pressure sensitive walkway measurements were highly correlated to each other (Pearson's correlation coefficient R = 0.98) and to actual weights (R = 0.99 for the weight distribution platform; 0.98 for the pressure sensitive walkway). Repeatability from day to day for both devices was greater than 0.99. For the weight distribution platform, the 95% confidence interval was ± 2.5% from the true percentage and ± 3.3% for the pressure sensitive walkway. The coefficient of variation (COV) was highest for both devices at the lightest weights (weight distribution platform 11.28%, pressure sensitive walkway 16.91%) and lowest with the heaviest weights (weight distribution platform 3.71%, pressure sensitive walkway 5.86%). CONCLUSION: Both the weight distribution platform and the pressure sensitive walkway provided accurate and consistent measures of weight distribution with no significant difference between devices. The rounded standard error was three percent for the weight distribution platform, and four percent for the pressure sensitive walkway. The higher variability when measuring the smallest weight suggests less accuracy at lower weights with both devices. CLINICAL SIGNIFICANCE: The weight distribution platform is a repeatable and accessible device to measure static weight distribution, and if proven the same in a clinical setting, it will be a valuable addition to current objective measures of limb use.

Biomechanical evaluation of adjunctive cerclage wire fixation for the prevention of periprosthetic femur fractures using cementless press-fit total hip replacement.

Periprosthetic femoral fractures are a common complication associated with cementless press-fit total hip arthroplasty. The use of prophylactic cerclage wire fixation has been advocated to reduce this complication. The objective of this study was to evaluate whether a double loop cerclage wire, used as adjunctive fixation, increased the peak torsional load to failure in femora implanted with press-fit cementless stems. Peak torsional load to failure was compared between femora without adjunctive fixation and femora receiving a 1 mm double loop cerclage wire placed proximally to the lesser trochanter. Femora treated with adjunctive cerclage wire fixation failed at 20% greater peak torque (P = 0.0001). In conclusion, a double loop cerclage wire may aid in the prevention of periprosthetic fractures associated with press-fit cementless femoral stems.

Assessment of an implant-skin interface scoring system for external skeletal fixation of dogs.

OBJECTIVE To assess intraobserver repeatability and interobserver and in vivo versus photographic agreement of a scoring system for the implant-skin interface (ISI) of external skeletal fixation (ESF). SAMPLE 42 photographs of ISIs from 18 dogs for interobserver agreement and intraobserver repeatability and 27 photographs of ISIs from 6 dogs for in vivo versus photograph agreement. PROCEDURES An ISI inflammation scoring system was developed. It included scales for 6 metrics (erythema, drainage amount, drainage type, swelling, hair loss or lack of hair regrowth, and granulation tissue). Photographs of the ISI of ESF were obtained by use of a standard protocol and evaluated to determine intraobserver repeatability and interobserver agreement (Cronbach α; 4 raters) of the ISI score. Agreement between in vivo and photographic ISI scores (2 raters) and correlation between median scores across metrics were evaluated. RESULTS 42 photographs met the inclusion criteria. Overall intraclass correlation coefficients ranged from 0.922 to 0.975. Interobserver overall Cronbach α ranged from 0.835 to 0.943. For in vivo versus photographic assessment, 27 ISIs in 6 dogs and their photographs were evaluated. The Cronbach α for both raters ranged from 0.614 to 0.938. Overall, the Cronbach α ranged from 0.725 to 0.932. Mean photographic scores were greater than mean in vivo scores for each metric. Pearson correlation coefficients ranged from 0.221 to 0.923. Erythema, swelling, and granulation were correlated with all other metrics. CONCLUSIONS AND CLINICAL RELEVANCE In this study, an ISI scoring system used in this study had high repeatability and agreement and may therefore be considered for use in clinical situations. Photographic scores were not equivalent to in vivo scores and should not be used interchangeably.

Tibial Plateau Leveling Osteotomy Plate Contouring and Proximal Load Screw Angulation Affect Osteotomy Compression.

OBJECTIVE: To evaluate the effect of contouring a tibial plateau leveling osteotomy (TPLO) plate, the associated angulation of the dynamic compression plate (DCP) hole relative to the long axis of the tibia, and angulation of the screw relative to the DCP hole on the osteotomy compression generated by load screws in a TPLO model. STUDY DESIGN: In vitro biomechanical study. STUDY POPULATION: Polyoxymethylene (POM) rod and synthetic cortical bone substitute model (n = 9). METHODS: The distal portion of a Slocum TPLO plate was attached to a horizontally positioned POM rod that was connected to a load cell. A segment of synthetic cortical bone substitute was attached to the end mount of the testing frame and adjusted to conform to the angle of the proximal portion of the TPLO plate. A 3.5 mm cortical bone screw was inserted in the proximal DCP hole and tightened to 1.5 Nm. The peak longitudinal load (N) was recorded. Screw insertion and data collection were repeated for proximal plate angles of 0-40° at 5° increments. RESULTS: A significant increase in the compression generated was observed as the plate angle was increased from 0° to 10°. The compression ceased to significantly increase until the plate was bent more than 20°, after which a significant decrease in compression was noted. A marked reduction in the compression generated occurred at plate angles greater than 30°. CONCLUSION: Angulation of the DCP hole and screw insertion angle can have deleterious effects on the magnitude of osteotomy compression.