Summary: An 18‐year‐old Standardbred mare that presented with clinical signs consistent with a subsolar foot abscess in the right hindlimb. Standard foot radiographs were unremarkable. Digital venography of the hoof demonstrated a significant lack of contrast filling in the terminal papilla, circumflex vessel and solar vessels in the region of the medial toe. Findings from the venogram were used to locate the abscess tract and establish drainage. Approximately 3 h after establishing drainage of the subsolar abscess, a second digital venogram was performed. This subsequent venogram revealed near complete resolution of the previously described contrast filling defects. The only deficit noted was a slight decrease in the filling of the terminal papilla in a small area at the medial toe. This case demonstrates the utility of digital venography as a simple, accessible imaging modality available to the field practitioner, providing more accurate lesion identification and localisation, resulting in faster resolution of a subsolar abscess.

Differences in horseshoe materials may have effects on gait that could change perceived esthetic qualities. Objective information regarding effects of shoeing on gait characteristics of horses is scant. The aim of this study was to determine differences in gait characteristics for horses under various experimental shoeing conditions (barefoot, aluminum shoes, steel shoes) on two surfaces (asphalt and soft footing) using body- and hoof-mounted sensors. We hypothesized that shoeing would affect hoof arc height during early (arc height a) and late (arc height b) swing phases but would not affect other gait variables. Twelve healthy, adult, client-owned horses were evaluated at a trot on asphalt and soft footing under the three experimental shoeing conditions. No significant (p < 0.05) effects of shoeing were detected for gait symmetry (Q score), mediolateral hoof deviation, stride length, or midstance, breakover, swing, and landing stride phase times. Hoof arc height a was significantly (p < 0.001) lower for aluminum versus steel shoes for right and left forelimbs on asphalt and soft footing. Hoof arc height b was significantly higher for aluminum versus steel shoes on soft footing for left (p < 0.001) and right (p = 0.02) forelimbs. Findings indicate that shoe weights affect early and late swing phase hoof heights differently. Further investigation is warranted to determine whether measured hoof arc height changes affect subjective esthetics of gait.

Objective: The objective of this video is to demonstrate a reliable technique for obtaining diagnostic venogram images of the equine foot. Venogram studies are indicated to assess vascular contrast filling of the equine digit, primarily in cases of laminitis. Animals: A healthy university-owned horse was used for demonstration purposes. The protocol was approved by the Virginia Polytechnic Institute and State University IACUC. Methods: The horse’s shoes are removed, and the foot is cleaned of debris. The horse is sedated and a medial and lateral abaxial nerve block performed. The pastern is clipped if the hair coat is long. An aseptic scrub is performed on the pastern, and the horse is placed on radiographic positioning blocks. An Esmarch tourniquet is placed at the fetlock, and a 21-gauge butterfly catheter is inserted into the palmar digital vein. Iodinated contrast is injected; immediately following contrast injection, radiographic views are obtained. Weight-bearing lateral-medial, weight-bearing dorsal-palmar, upright pedal/dorsoproximal-palmarodistal oblique, unloaded lateral-medial, unloaded dorsopalmar, and late weight-bearing lateral-medial and dorsopalmar images are our standard views. The tourniquet is removed, followed by removal of the butterfly catheter and a light bandage placed over the venipuncture site. Results: Radiographic images are obtained and reviewed by clinicians to determine whether there is decreased or abnormal vascular contrast filling of the foot. Clinical Relevance: Findings from the venogram study can guide shoeing and other treatment choices, particularly for laminitic horses.

Background: Heel movement is critical to shock absorption and vascular perfusion of the equine digit. Conventional horseshoeing techniques are suspected to restrict natural hoof deformation, affecting hoof biomechanics. Several studies have explored the effects of shoeing on hoof function, though many have been limited to artificial conditions, cadavers, or homogenous populations. Objective: We aimed to compare the effects of two aluminium shoeing techniques, nail‐on versus indirect glue‐on fabric cuff shoes, on heel movement in horses. Our objective was to determine which technique allowed greater heel movement on hard and soft footing. Study Design: A controlled in vivo experimental study using a repeated‐measures design. Methods: Fifteen healthy horses underwent three trials: (1) indirect glue‐on fabric cuff shoes, (2) barefoot, and (3) aluminium nail‐on shoes. A displacement sensor was affixed to the heels of one forelimb. Measurements were taken on hard and soft footing. Data were analysed using mixed‐model ANOVA to determine differences in heel movement. Results: Heel movement was significantly greater when barefoot ( p < 0.0001). Mean heel displacement for the walk on hard ground was highest in barefoot horses (3.03 ± 0.67 mm), followed by glue‐on shoes (2.23 ± 0.58 mm), and aluminium nail‐on shoes (1.96 ± 0.48 mm). At the trot, mean heel movement was greatest in barefoot horses (3.29 ± 0.62 mm), followed by glue‐on shoes (2.56 ± 0.55 mm), and aluminium nail‐on shoes (2.12 ± 0.47 mm). Main Limitations: The two main limitations were: (1) The lack of an absolute zero baseline measurement, preventing differentiating between heel expansion and contraction. (2) Low heel conformation in some horses prevented recordings on soft footing, reducing the statistical power. Conclusions: This study reinforces previous findings that shoeing restricts heel movement. Indirect glue‐on shoes allow for more heel movement than nail‐on shoes at the trot; both techniques limit heel movement compared to barefoot.

Summary: Background: Thrush, abscesses, white line disease and cankers are life‐threatening infections common in equine hooves. Copper has a history of medicinal use on equine hooves. There is a paucity of scientific evidence supporting the use of metals as antimicrobial agents in equine podiatry. Additionally, there is growing interest in discovering alternatives to copper. This report describes the process through which various metals inhibit the growth of bacterial pathogens using an equine hoof model. Objectives: To report the results of exposure of clinically relevant hoof pathogens to various metals and determine the best method of application (i.e. route of exposure) of these metals to the pathogens. Study Design: In vitro culturing of bacteria exposed to various metals. Methods: Lawns of Escherichia coli were cultured anaerobically at 24°C for 1–8 weeks on the surface of nutrient agar with silicone padding placed on top. The silicone padding either encapsulated the metal (copper, zinc and silver) or allowed it to come into contact with the bacteria. After the initial incubation, the agar was moved to glass beakers containing 200 mL nutrient broth and incubated at 26°C and 95 rpm for 24 h. Then, the broth cultures were serially diluted and plated onto fresh nutrient agar plates to determine the survival of E. coli underneath the silicone padding. Any growth indicated the survival of E. coli after it came into contact with the metal. Results: Growth of the bacteria was inhibited if the metal was free to diffuse away from the silicon padding or was in direct physical contact with the bacteria. Main Limitations: Escherichia coli is a model pathogen representing Treponema sp. and Fusobacterium necrophorum . This work was conducted entirely in vitro. Conclusions: Metals are efficacious antimicrobial agents in equine podiatry. Diffusion of the metal away from the padding is crucial for antimicrobial activity.