Laminitis

Laminitis is a painful and potentially devastating condition affecting the sensitive tissues (laminae) within the hoof capsule.

There are many different causes and all types of horses and ponies can be affected.

RECOGNISING LAMINITIS & HORMONE DISORDERS

Early recognition is key to successful management. Significant laminae changes can occur before your horse or pony shows outward signs of laminitis.

Acute

Rocked-back stance, weight shifting, increased lying down, increased heat and pulses to feet, pain over sole at point of frog, elevated breathing rate and effort.

Chronic

Excessive heel growth with divergent hoof wall rings, recurrent foot abscesses, short stride.

PPID

Abnormal hair shedding (from long hairs on chin and abdomen to excessive curly coats), patchy sweating, increased drinking and urinating, fat pads above eyes, lack of energy, increased susceptibility to infections and laminitis, loss of muscle mass and body condition.

EMS

Overweight, abnormal fat distribution (usually over crest and rump), recurrent laminitis.

DIAGNOSIS

We use the following to reach a prompt, accurate diagnosis:

Detailed history

Diet and exercise regimes, recent management changes and previous clinical problems are considered.

Thorough clinical examination

In addition to standard clinical examination, body condition, stance at rest, and movement in straight lines and tight turns is observed. Hoof conformation, digital pulses and reaction to hoof testers are assessed. In extreme cases where pain is too severe, first aid treatment is administered before movement or limb lifting is attempted.

Digital radiography

X-rays provide vital information on the position of the pedal bone within the hoof and the presence of gas or fluid from laminae damage or abscesses. Measurements are made directly from the images to quantify severity of pedal bone movement.

Blood sampling

Laboratory analysis can detect underlying hormonal conditions which may be causing laminitis. PPID cases are identified by measuring baseline ACTH levels. EMS cases are most accurately diagnosed using a dynamic test. The patient is starved for 12 hrs then fed a small feed containing glucose 2 hours prior to blood collection.

Your horse or pony may develop laminitis for a number of different reasons:

Pasture: Quality is as important as quantity. Grass which has been heavily fertilised or stressed by frost or overgrazing will contain high levels of the sugar called fructan which is closely linked with laminitis.
Grain: High volumes will cause a non-grass carbohydrate overload that may induce laminitis.
Hormonal disorders: Pituitary Pars Intermedia Dysfunction (PPID) (Equine Cushing’s Disease) and Equine Metabolic Syndrome (EMS) cause systemic hormonal changes which increase the risk of developing laminitis.
Underlying toxic disease: Toxins circulating in the body from other disease processes (e.g uterine infection following a retained placenta) can cause a cascade of reactions resulting in laminitis.
Dependent limb laminitis: Occasionally laminitis develops when a severe lameness in one limb (e.g. foot abscess, fracture) causes overloading of the opposite limb.
Drugs: Certain drugs (e.g corticosteroids) can induce laminitis. The risk is very small when correct doses are adhered to.

TREATMENT

A number of first aid treatments are common to all laminitis cases, however, identification of the underlying cause is vital for successful management.

We recognise laminitis as a medical emergency and aim to provide prompt, effective treatment based on the most up-to-date research information.

FIRST AID

Strict box on a deep shavings bed provides comfort and restricts movement. This is important as the pedal bone is vulnerable to rotation or sinking within the hoof capsule due to laminae damage. Hard feed and treats should be removed from the diet. Soaked hay should be offered in small nets at a rate of 1.5 to 2.0% bodyweight per day.

Following a veterinary examination, anti-inflammatories and mild sedatives are usually given and appropriate hoof support pads are applied.

UNDERLYING CAUSE

While removal from inappropriate pasture or grain source is straight forward, treatment of hormonal disorders is more challenging. PPID can be controlled using the oral tablet Pergolide. The dose required must be determined on an individual basis and regular blood samples for ACTH levels are required. EMS cases may benefit from an oral drug called Metformin, however, diet and exercise management is often more important.

Early aggressive management of toxic conditions involves physical removal of toxin source and treatment with anti-endotoxic drugs, anti-inflammatories and appropriate antibiotics.
Pre-emptive foot support of the opposite limb in severe lameness cases can be helpful in preventing dependent laminitis, combined with close attention to sufficient pain relief and support for the original condition.

Courses of laminitis-inducing drugs should be stopped immediately laminitis is suspected.

ONGOING MANAGEMENT

Regular check ups are essential to monitor response to initial treatment and plan further management. Farriery is a crucial component and our mobile digital radiography units allow us to take images at the yard for your farrier to work from. This ensures the hoof is trimmed accurately and an appropriate shoe is chosen. ACTH levels should be checked every 6 weeks initially following PPID diagnosis and every 6 months as the condition is slowly progressive. We encourage use of the interactive online aftercare service, Care and Connect (Boehringer Ingelheim) to monitor your individual horse or pony’s PPID condition and recommend the use of our Plum Park weigh bridge at the clinic to assist weight control.