Horse Flashcards
Thrush
- infection with subsequent necrosis of the frog and sulci
- characterised by foul- smelling odour and soft and slimy horse
- if it reaches sensitive lamine = podo dermatitis
Factors influencing thrush
Urine and faeces present in the box that dissolve the horn due to presence of fungi and bacteria, so horses kept in bad environments are prone to thrush
Management of thrush
Good stall hygiene, hoof care and local treatment
Treatment for thrush
- remove damaged horn and disinfect hoof (iodine, copper sulphate and formalin in small cotton balls applied into the sulci)
- if podo dermatitis, bandage with povidone-iodine is applied. With adequate stall hygiene and hoof care the prognosis is good
White line disease
- white line with a poor-quality horn allows the colonisation of bacteria and fungi with the resultant loss of bond between the hoof and sole
- characterised by a keratinoly tic process that originates on solar surface of the hoof
- with separation, there’s an increase in tensional forces that results in inflammatory processes into sensitive laminate and subsequent lameness
Factors influencing white line disease
Warm and humid climate
Treatment for white line disease
Improving stall hygiene, removal of altered Horn and bactericidas and fungicidal agents
Hoof wall cracks
- longitudinal disruption of the hoof wall, parallel with horn tubules
- it can have several lengths:
> whole hoof wall length, only próximal/only distal hoof wall
> can penetrate only superficial or extend into sensitive laminate - horizontal hoof cracks (parallel to the coronet) - hoof crevices
Causes of hoof wall cracks
Poor horn quality, abnormal hoof angles (tension gradients within the hoof wall), poor hoof hygiene, excessive workload, local trauma (proximal), uneven heals
Diagnosis of hoof wall cracks
By visual inspection
Treatment of hoof wall cracks
- depends on the location and depth of the crack
- improve hoof care and shoeing
- all altered horn adjacent to the crack is removed, the defect is cleaned, a hoof bandage application and application of a bar shoe with clips on each side of the crack
- trimming ht hoof wall just below the crack (reduces the movement of coronary band -> production of better horn)
- fixation devices can be used (umbilical tape, clam,p, metal plates) over the crack (reduces movements against each other and unites two separate parts)
Prognosis of hoof wall cracks
Guarded to good, since crack often recurs
Keratoma
- thickening of the hoof horn that extends towards the inside of the hoof
- mostly columnar shaped (parallel to horn tubules) and less frequently a spherical form
- typically formed in dorsal to dorsomedial and lateral parts of the hoof wall
- it’s a space-occupying mass causing pressure necrosis of P3 and soft tissue
- it causes drainage from the white line or coronary band and lameness
Diagnosis of keratoma
Radiography (smoooth, circumscribed lysis of the P3), CT and MRI better for surgery
Treatment for keratoma
- complete keratoma removal with hoof wall support
- removal of abnormal hoof wall and sensitive laminate, hoof wall defect filled with artificial Horn and shoe with large clips on either side of the defect
Prognosis of keratoma
Very good after srurgical treatment
Acute hoof abscesses
One of the most common cause of lameness that are caused by penetration of bacteria across the hoof wall - infection of sensitive lamellar - purulent material inside the hoof capsule
Pressure inside the hoof capsule causes severe pain
Aetiology of acute hoof abscess
- horseshoe nail too close or directly into sensitive lamine
- rocks/street nail penetrating the sole, complication of a sole bruise
- nail prick-penetration of the sensitive hoof structure by a horseshoe nail
Signs of acute hoof abscess
Severe lameness, fever, warm foot, swelling of the distal limb, marked positive response to hoof tester
Treatmentt for acute hoof abscesss
- shoe removal, location hoof tester, povidoine bandage to soften the horn -> location and subsequent drainage of the abscess
- removal of necrotic and undermined Horn, cleaning with iodine of max 3% H2O2, iodine-soaked gauged and bandage
- NSAIDs and ATB if deep structures are involve
Chronic hoof abscess
- breaking at the coronary band, invading the coffin joint, undermining the sole, penetrating distal phalanx
- opening of the abscess and removal of the undermined horn
- if P3 is involved, curettage of the affected bone
- systemic and local ATB therapy is often needed
- treatment takes several weeks to months
Aseptic podo dermatitis
Very common cause of lameness and represents bruising of horn tissue of the hoof
Cause of aseptic pododermatitis
Poor shoeing technique, hard, dry, uneeven ground
Diagnosis of aseptic pododermatitis
Clinical exam -> foot is slightly warmer, increased pulsation of palmar arteries, positive reaction on hoof tester palpation
Palmar digital or a axial nerve block release lameness
Radiohtphy
Treatment for aseptic pododermatitis
Remove the cause, moist bandage for 3-5 days, followed by a dry bandage
puncture wound
- nails in middle of the frog are most dangerous
- penetration object is always contaminated
- puncture wounds must be treated as an emergency
signs of puncture wounds
- severe supporting limb lameness, warm hoof, increased pulsation of digital arteries, severe pain on hoof tester
- radiography before removal (clean, examine hoof and remove object)
treatment of puncture wounds
- surgical debridement of puncture wound, flushing involved synovial structures under GA
- deep digital flexor tendon (DDFT) resection if penetrated, curettage if bone involvement
- broad spectrum ATB
coronary laceration
laceration at transition between skin and hoof capsule
cause of coronary laceration
overreaching or trauma
signs of coronary laceration
- severe lameness, infection within hoof capsule, risk of permanent damage to horn producing structures abnormalities of hoof growth
treatment of coronary laceration
- removal of the damaged horn, cleaning, primary closure, and hoof cast application
canker
- abnormal horn proliferation, frog region (sole, wall, skin) not a true neoplasm, chronic inflammation-parakeratosis
- hypertrophy of sensitive laminae and degeneration of superficial horn and corium
- hind limbs are more often involved one or more hooves
predisposition of canker
moist, long-standing thrush, spirhochaetae, anaerobic bacteria/bovine papilloma virus
signs of canker
- lesions involve primarily the frog sulci but can spread to other structures
- rubber-like horn, friable horn, soft, greasy, cauliflower like growths
- odour is present and horse reacts painfully to pressure and horn bleeds easily
diagnosis of canker
histology of resected material to confirm the diagnosis
treatment of canker
- difficult due to reoccurrence
- surgical debridement of abnormal horn under local anaesthesia, bandage until new horn grows, disinfection solution, and metronidazole local
- systemic ATB in more severe cases, pred
- biotin and zinc feed supplements
third phalanx fracture
- common in both foals and adults horses
- more common in forelimbs
cause pf P3 fracture
trauma (excessive work, kick)
different types of P3 fracture
- abaxial without joint involvement
- abaxial with joint involvement
- axial/sagittal and peri sagittal fractures
- fractures of the extensor process
- comminuted (multi-fragment) fracture with joint involvement
- solar margin fractures
signs of P3 fracture
- acute, moderate-severe lameness, warm hoof, increased digital pulse and pain on the hoof tester
- blood in synovial fluid in distal interdigital joint (DIJ) if joint involvement
radiology of P3 fracture
- false negative possible, several views needed
- negative radiology: stall rest and repeat after 7-10days
- scintigraphy, MRI and CT
treatment of P3 fracture
- type I: fibreglass casts, bar shoe with large side clips, 2-4months stall rest with reasonable prognosis for athletic function
- type II, III: conservatively or surgical, surgery with intraoperative imaging-CT, lag screw technique. Complications-infection, abscess formation; conservative stall rest 4 month
- type IV-hyperextension, avulsion injury, separate centre of ossification, OCD, lameness, nerve blocking necessary, removal of small fragments by arthroscopy. Stabilisation of large fragments with lag screws
- type V: fibreglass cast, surgery, poor prognosis
- type VI: high prevalence in young thoroughbred foals, trauma, after chronic laminitis, conservative, fragment removal if infected
navicular syndrome
- palmar foot pain
- lesions are present at distal sesamoid bone and surrounding structure
- podotrochlear apparatus: navicular bone (NB), collateral sesamoideum ligaments (CSLs), distal sesamoideum ligament-impair (DSIL), navicular bursa, distal digital annular lig
predisposition of navicular syndrome
- warmbloods, thoroughbreds, quarter horse, rare in finnhorse, arab, Friesian, ponies
- mature horses are more common
- conformation: long toe/underrun heel, small foot and large body mass subtle pain-no extension of the forelimb, short, choppy gait
signs of navicular syndrome
mild to moderate uni or bilateral forelimb lameness, exacerbation on the circle
diagnosis of navicular syndrome
- toe first landing
- no diagnostic test for pathognomonic for palmar foot pain
- radiography (x-ray, CT, MRI) grading system 0-4/degrees of lameness poor correlation with radiology
treatment of navicular syndrome
- trimming/shoeing: correct, preserve mediolateral, dorsopalmar balance, easy breakover, protection palmar aspect from concussion, straight hoof-pastern axis, adding concussion protection to the foot, allow hoof expansion
- NSAIDs, intraarticular medication
- bisphosphonate therapy-reduction of bone resorption and modelling
- extracorporeal shock wave treatment
- surgical treatment: tenoscopy, bursoscopy-visualisation of tendon injuries, desmotomy, etc
laminitis
- inflammation of pedal laminae – decreased support between hoof wall and P3. Breakdown of CT suspensory apparatus of P3 and inside hoof wall laminar attachment unable to support P3 P3 displaces
- clinical syndrome associated with systemic disease (endocrine, sepsis, SIRS) Endocrinopatic is a predominant form
cause of laminitis
- important to find the underlying cause
- EMS, oral sugar test, PPID, etc
- bacteria: strep bovis: rapidly proliferated in carb overload and after died releasing cellular components that could potentially pass mucosal barrier