Lameness in Horses (Quittor, Quarter Crack, Whiteline Disease) PDF

Republic of the Philippines Benguet State University COLLEGE OF VETERINARY MEDICINE La Trinidad, Benguet DEPARTMENT OF CLINICAL SCIENCES...

Republic of the Philippines Benguet State University COLLEGE OF VETERINARY MEDICINE La Trinidad, Benguet DEPARTMENT OF CLINICAL SCIENCES VM 173 EQUINE MEDICINE RUBRICS NAME OF STUDENT: ______________________________ TOPIC: __________________________________ CATEGORY BEGINNING DEVELOPING ACCOMPLISHED EXEMPLARY SCORE 20 30 35 40 Does not seem to Shows good Shows good Shows full understand the understanding of understanding of the understanding of the topic very well. parts of the topics. topics. Most of the topic. All information CONTENT Information has Information clearly information clearly clearly relates to the (40%) little or nothing to relates to the main relates to the main main topic with do with the main topic with no topics with few several supporting topic. supporting details. supporting details. details. 5 15 20 25 Limited response Satisfactory Good response to Excellent response to questions and response to class class questions and to class questions RESPONSE TO discussion with no questions and discussion with some and discussion with CLASS QUERIES reference to discussion with connection made to appropriate content (25%) theory/research limited reference to theory/research supported by theory theory/research and research 2 5 10 15 Hard to follow the Most ideas flow but Clear flow of ideas. Very clear and flow of ideas. focus is lost at Stands up straight concise flow of Slouches and/or times. Sometimes and establishes eye ideas. Stands up DELIVERY does not look at stands up straight contact with everyone straight, looks (15%) the audience and establishes eye in the room during the relaxed and during the contact presentation confident. presentation Establishes eye contact with everyone in the room during the presentation VISUALS 2 5 10 15 AND No use of visuals Limited use of Use visuals related to Visuals augmented TIMELINESS Uploaded a day visuals loosely the topic and extended (15%) after/on the day of related to the topic comprehension of reporting the topic Uploaded a day before reporting FORMAT 2 3 4 5 (5%) The information Information is Information is Information is very appears to be organized but organized with well – organized with well disorganized paragraphs are not constructed – constructed well constructed paragraphs paragraphs and subheadings TOTAL SCORE ______________________________________ ____________________ NAME AND SIGNATURE OF EVALUATOR DATE Republic of the Philippines Benguet State University COLLEGE OF VETERINARY MEDICINE La Trinidad, Benguet DEPARTMENT OF CLINICAL SCIENCES VMED 173 EQUINE MEDICINE LAMENESS (Quittor, Quarter Crack, White Line Disease) SUBMITTED BY: YODONG, Cheyenne Gale C. DATE SUBMITTED: August 08, 2024  Quittor I. Introduction Quittor describes a chronic, purulent inflammation of the collateral (ungual) cartilages of the foot of the horse. It is often the result of prior wounds to the area, causing the horse to present moderate to severe lameness. This condition involves the necrosis of the collateral cartilages or sidebones of the foot. It usually affects the front feet and is more frequently seen in the heavy or draft breeds of horses compared to the light breeds and ponies. Fig 1. illustration of Quittor on the horse, featuring the discharging sinuses. Although infection remains the most common cause of lameness to horses, quittor is relatively uncommon. II. Etiology The collateral cartilages of the pedal bone have a poor blood supply which explains why they respond poorly to infections and consequently becomes chronic and damaging. Quittor can be caused by “treads” and any type of direct, external trauma or penetrating injury to the coronary band area above the lateral cartilages. It may also, although rarely, be caused from extending subsolar abscesses. III. Clinical Findings ❖ Early Stage (Inflammatory Stage) Pain and swelling over affected region Lameness ❖ Severe Stage Formation of pus discharging tracts or sinuses from the coronary band or above it Necrosis of affected cartilage Lameness  Fig 2. An image of a severe case (left) with bleeding and a moderate case (right) of quittor in horses. Lameness can come and go, ranging from mild to very severe. The horse might not show signs of lameness during an exam because the pain often eases once the infection drains. This drainage lets out pus and fluids, reducing pressure and pain for a while. However, if the issue persists for a long time, it can cause the hoof wall to become deformed. IV. Diagnostics ❖ Clinical Examination Diagnosis of quittor is often based on clinical signs. ❖ Radiography May show necrosis of the sidebones or gas shadows, indicating infection Can reveal ossification of the collateral cartilages, depending on the condition’s stage. ❖ Injection of Iodinated Contrast Material ❖ Ultrasonography V. Treatment/ Prevention/ Control Surgery (debridement) to remove diseased tissue and cartilage is usually successful. Drug treatment alone is likely to fail. Without treatment and drainage: ○ Cartilage will die. ○ Abscesses will recur and extend to deep structures. ○ Long-term lameness will result. Extensive damage involving the distal phalangeal (coffin) joint leads to an unfavorable recovery outlook.  Quarter Crack I. Introduction A quarter crack is a type of sand crack along with toe cracks and heel cracks. A sand crack is a general term for any crack or fissure in the hoof wall that typically runs vertically, parallel to the coronary band. Quarter cracks are located on the sides of the hooves. This condition is common in horses, especially racehorses and other equines in hard training and performance. They vary in depth – from shallow to long and deep and may cause serious lameness. Fig. 3,4. Illustrations of a horse’s hoof anatomy. Quarter cracks are vertical splits, usually originating at the top of the hoof, from the horse’s coronary band and proceeding toward the bottom of the hoof, following the natural growth of the hoof wall. Although similar, quarter cracks are more likely to cause lameness compared to that of toe cracks. Fig. 5. Horse hooves showing sand cracks. II. Etiology  Quarter cracks often arise from abnormal hoof or limb conformation, leading to improper foot landing. They can also develop due to prolonged stress or pressure on a specific hoof area. Horses with sheared heels are particularly susceptible, as the displacement of the coronary band can cause the collateral cartilage to impact the coronary band’s axial surface, fostering crack formation. A genuine quarter crack starts at the coronary band and can result in hoof wall instability, inflammation, and infection. Quarter cracks may also be caused by several other factors: (Anderson, 2022) Poor health and management leading to poor hoof quality and growth − Poor Nutrition − Poor Sanitation − Lack of exercise Exposure to moisture − For horses with history of this condition, moisture might be enough to cause reoccurrence. Conformational Issues − Limb Conformation − Limb position during loading − Gait abnormalities Imbalanced Trimming or Shoeing Fig. 6. An illustration depicting some of the possible conformational issues of a horse’s hooves that may cause quarter cracks along with the supposed conformation. Hoof cracks in horses are thought to result mainly from excessive forces placed on the hoof wall. Hoof cracks can occur in a horizontal or vertical orientation; they can be further classified by location, depth, and length. (Beasley, 2024) Full-thickness cracks extend through the entire thickness of the hoof capsule. Partial-thickness cracks extend through only part of the thickness of the hoof capsule. Complete hoof cracks extend from the ground surface of the hoof wall to the coronary band. Incomplete cracks start either distally or proximally but do not extend the entire length of the wall III. Clinical Findings  Quarter cracks can typically be observed by the naked eye because they are often visible as a clear split or separation in the hoof wall. However, the crack can also be very fine and be hidden by dirt, which can make it difficult to determine. In that case, closer inspection may be necessary. Horses with the condition may also exhibit sensitivity and lameness of varying severity depending on the depth of the crack and whether it is infected – deep cracks can easily become infected, leading to inflammation and discharge from the hoof. In severe cases, bleeding may also occur from the crack. IV. Diagnostics The first step in treating and healing a quarter crack is determining why the crack appeared. Radiographs can reveal the position of the coffin bone, which may be naturally tipped slightly toward the inside or outside of the hoof. Visual Examination Radiography ○ Can show the position of the coffin bone, which might be slightly tilted inward or outward. Fig. 7. Normal position of the coffin bone  Fig. 8. Tilted coffin bones that may affect the horse’s gait and cause sand cracks. Hoof Testers ○ Involves the use of large steel pincers to apply focal pressure to specific areas of the hoof and locate punctured or bruised areas of the horse’s hoof. Fig. 9. Hoof testers being used on a horse’s hoof. Severe coronary band injuries may disrupt hoof growth in the area of the wound, leaving the hoof weak and subject to cracking. Shoes that don’t properly support the heel can be diagnosed by a competent farrier. V. Treatment/ Prevention/ Control Most partial-thickness hoof cracks don’t cause lameness and are treated for cosmetic reasons. For lameness-inducing cracks like true quarter cracks, treatment focuses on identifying and addressing underlying causes, cleaning affected tissues, and stabilizing the hoof wall. Proper trimming and balancing are crucial for healing. Stabilizing the crack allows the horse to continue working while it grows out. Infected or bleeding cracks shouldn’t be fully covered to avoid abscesses. The prognosis depends on the crack’s location and depth, with a good outlook if the underlying cause can be corrected. For quarter crack repair, it’s essential to correct the underlying cause and stabilize the defect. This often involves using stainless steel wires and an acrylic composite with Fiberglass. The type of shoes the horse wears is crucial for the successful treatment of a quarter crack. Bar shoes increase the ground surface of the foot, providing support and reducing independent vertical movement at the heel bulb on the affected side. Aluminum shoes applied with glue offer several advantages. Glue-on shoes allow the foot to be trimmed and shod to the most suitable conformation, eliminate concerns over nail placement in the hoof, and provide increased support. Glue-on shoes are ideal for racehorses. Fig. 10. Toe crack treated with hoof adhesive Fig. 11. Quarter crack being treated with steel wires to avoid further damage and separation of hoof crack.  Fig. 12. Bar shoes on horse hoof to correct and stabilize defect. Fig. 13. Glue on horse shoes. These are ideal for racehorses. White line Disease (WLD) I. Introduction White line disease (WLD) is an infection localized to the hoof that can lead to pain and lameness. This condition is a keratolytic condition affecting the deeper layers of the stratum medium of the equine hoof wall in one or more hooves at a time. The term “white line disease” does not exactly mean that the disease is at the white line itself. The exact site of the affected area lies just in front of the epidermal laminae. This disease usually develops due to the separation of the hoof wall at the inner part of the stratum medium, which just so happens to be the softest and non-pigmented part of the hoof wall. The separation can now expose the inner part of the hooves to various microorganisms which can take advantage of the situation. These opportunistic microorganisms now aim for a weak spot and proliferate, extending more proximally to the hoof wall. Fig 14. Anatomy of the horse’s hoof showing the white line, inner wall, and the laminae. II. Etiology The exact etiological agent of this disease is unknown. This means that various factors affecting the horse can cause it. Common causes that start the development of WLD are usually the following (King, 2023): Poor quality hoof, Poor hoof conformation, A split or crack in the hoof An environment with too much moisture like continuous wet pastures An environment that is too dry, predisposing the hoof to crack Horses with chronic laminitis Negligent foot care, such as letting it grow too long Although fungi and anaerobic bacteria are involved in the process of causing disease, it is not the main cause of the disease. It only fully develops once that fungi, or opportunistic pathogens get a hold of a weak spot in the hoof, which enables them to grow in number and cause WLD. The keratolytic process then creates cavities within the hoof full of air and degenerating horn. The WLD can be present in only one hoof or multiple hooves at a time. It can occur in any region of the white line in the hoof capsule. Lesions associated with inflammation of the tissues are not commonly observed in WLD. During severe cases of WLD, where a large fraction of the hoof wall is damaged, the support from the laminae will be absent and the coffin bone may shift from its original location. III. Clinical Findings The signs of this disease is usually insidious, making it more difficult to observe. Hoof Wall Separation: The hoof wall may start to separate from the sole, creating a gap. Crumbly or Chalky Material: You might see a crumbly or chalky substance in the white line area. Lameness: The horse could show signs of lameness, especially if the infection progresses. Hoof Sensitivity: The affected area may be sensitive to touch. Foul Odor: There could be a bad smell coming from the hoof due to bacterial or fungal infection.  Fig 15. White line disease featuring white, chalky powder or crumbled bits on the sole of the hoof. IV. Diagnostics It is difficult to diagnose white line disease as it is hardly recognizable during the early stages. At the early stages, the hoof capsule looks normal and lameness is not observed as well. A way to diagnose it will need the veterinarian to do a closer visual inspection using a probing instrument. This can reveal a cavity in between the inner and middle layers of the hoof. Dryness or necrotic tissues and debris can be seen alongside possible fungal or bacterial infection. As the disease progresses, it will also be easier to see the problem in the hoof. Hoof testers can be used to check if the hoof has tender soles and the sole will also gradually get flatter. Radiography can also help with the visualization of this disease. Fig 16. A radiologic image showing a space between the hoof wall and the laminae where microbes may enter and cause infection that can lead to White Line Disease. V. Treatment/ Prevention/ Control Treatment Hoof Wall Debridement ○ Remove the affected hoof wall to allow medications to reach the infected area Prevention Daily Hoof Cleaning ○ Clean the hooves daily and monitor the integrity of the white line Dry Living Environment ○ Ensure the horse's living environment is clean and dry Proper Diet ○ Provide high-quality forage and horse feed to maintain hoof health Regular Trimming and Shoeing ○ Maintain regular hoof trimming and proper shoeing Control Early Detection ○ Regularly inspect hooves for early signs of white line disease Environmental Management ○ Change wet bedding frequently to prevent moisture buildup Professional Care ○ Work with a farrier and veterinarian to manage and treat the disease effectively References: Anderson, M. (2022, June 22). Quarter cracks in horses: Causes and treatment approaches. The Horse. https://thehorse.com/196882/quarter-cracks-in-horses-causes-and-treatment-approaches/ Beasley, B. (2024, June 4). Hoof cracks in horses. MSD Veterinary Manual. https://www.msdvetmanual.com/musculoskeletal-system/disorders-of-the-foot-in-horses/hoof-cracks-in-ho rses Bell, Y. (2020, April 14). White Line Disease – diagnosis, Treatment, & Prevention. Equiniction. https://www.equiniction.com/white-line-disease/ Courtney. (2023, September 25). Glue on HorseShoes. An Equestrian Life. https://anequestrianlife.com/2023/03/glue-on-horseshoes/#google_vignette Craig, J. (2022, March 30). Measuring the equine hoof in radiographs — a focus on calibration. Medium. https://medium.com/eponamind/measuring-the-equine-hoof-in-radiographs-7db141bd28f2 Foundation Equine NJ. (n.d.). Quittor. Foundation Equine Wellness and Management. Retrieved August 6, 2024, from https://foundationequinenj.com/storage/app/media/FE_Client_Ed_Flyers_2021/QUITTORfeFlyer2021.pdf How to prevent and treat white line disease in horses. (n.d.). https://www.americanfarriers.com/articles/12939-how-to-prevent-and-treat-white-line-disease-in-horses King, A., DVM. (2023, September 8). White line disease in horses. PetMD. https://www.petmd.com/horse/conditions/musculoskeletal/white-line-disease-horses Loving, N. S., DVM. (2024, July 26). White line disease in horses. EquiManagement. https://equimanagement.com/research-medical/white-line-disease-in-horses/ Margherita, J. (2023, August 4). Beating white line disease in horses’ hooves. Best Hoof. https://besthoof.com/beating-white-line-disease-in-horses-hooves/ Rice, S., & Rice, S. (2024, July 13). Quittor (Collateral Hoof Cartilage Infection) in horses: Risk factors, treatment & Prevention | Mad Barn. Mad Barn USA. https://madbarn.com/quittor-in-horses/ Utah State University. (2023, December 14). Proper basic hoof care. USU. https://extension.usu.edu/equine/research/proper-basic-hoof-care White line disease in horses: causes, symptoms, and solutions. (n.d.). Med Vet Pharmaceuticals. https://www.medvetpharm.com/blog/white-line-disease-horses White Line Disease - The Equine Podiatry Association. (n.d.). The Equine Podiatry Association. https://www.epauk.org/about-equine-podiatry/articles/white-line-disease/?doing_wp_cron=1723076343.50 38819313049316406250#:~:text=What%20is%20White%20Line%20Disease,White%20Line%20Disease %E2%80%9D%20is%20misleading.