- The Equine Lymphatic System explained.
- Clinical treatment of CPL
- The treatment contraindications that you need to know about – including NOT increasing circulation and the “rebound effect“.
Equine Lymphology
Learn about equine lymphology in the lessons below. Find out how the lymphatic system works, what makes it stop working and how feather mites can trigger CPL. We also learn the differences between primary and secondary lymphoedema and why the term ‘Chronic Progressive Lymphoedema’ is something of a misnomer.
Important references for CPL specifically:-
- Session 2 Figures 1 – 5: Diagrams of the nodes, ILVs, collectors and lymphatic system.
- Session 3: Skin territories. This is important to know when treating CPL as most therapeutic services need to avoid directly working on the affected skin territories (territory 3 for front limbs and 7 for hind limbs), which are far more extensive than one might expect.
- Session 3 Paragraph 15-16: How scarring and feather mites can trigger CPL in the genetically pre-disposed horse.
- Session 4 Figures 1 – 3: Dissection showing lower leg lymph vessels, diagrams showing the deep drainage of the body and hind limb.
Equine Lymphology and the Treatment of CPL
Sadly, we are now learning that the Manual Lymphatic Drainage (MLD) component of Combined Decongestive Therapy (CDT) is not particularly helpful for horses with CPL due to the extent of the damage to the lymphatic system. So medically-correct compression is the only tool we have and even that is little help in the advanced stages.
“Of all the horse’s biomechanical systems, perhaps one that is least understood or looked at is the lymphatic system. Much of our current research on equine lymphology has been conducted at the Veterinary University at Hannover in Germany, where they have discovered significant differences between the equine lymphatic system and that of the humans, and this has profound implications on the way we need to look at and treat lymphatic problems as well as how we keep and manage horses on a daily basis.”
Rebecka Blenntoft
(Photo credit DB von Rautenfeld)
Schools of Lymphology
Vodder, Foldi, Le Dec and Casley-Smith are all proper schools of lymphology and it is worth sourcing a qualified graduate to take advice from.
The Vodder Schule is incredibly comprehensive, comprising four stages of learning and it is only the third and fourth that qualify graduates to practice lymphoedema care. So it is worth checking your therapist’s credentials to ensure they are actually allowed to practice lymphatic therapy.
Contraindications
It is an unfortunate fact that the current treatments available to lymphoedema patients (both human and equine) are sub-optimal and for many, all we can do is utilise medically correct compression applied by properly qualified CDT practitioners, alongside a holistic approach to daily care. For more detailed information on further contraindications click here.
⭕ Ice/cryotherapy including ice boots, wraps, gel
Ice can hasten the progression of the disease and must not be encouraged.
The application of ice or very cold temperatures impedes the ability of the lymphatic system to transport lymph. The vessels will not work effectively. It also shuts down the microcirculation of the arterioles and venules. When the leg is removed from ice water there is a massive “re-starting” of the microcirculation – the arterial blood supply opens up (imagine a dam opening) and oxygen/nutrient rich blood fills the interstitium. This is sometimes called “rebound swelling” and greatly increases the burden on the lymphatic system.
The makers of such ice products/therapies then take samples and claim that they have increased blood flow, oxygen and nutrients which can only be a good thing… right? Sadly not for horses with lymphatic disease because it is the circulatory and lymphatic systems that then have to take all of that flooding away. If we bear in mind how even the lymphatics of healthy horses are compromised when standing still, then its not hard to see how horses with CPL (already struggling with overloaded, inadequate lymphatics) will fare.
⭕ Heat
Exposure to heat, including hot water and direct sun is also suspected to affect the rebound process described above and can cause discomfort.
⭕ Incorrect compression garments/elastic bandages/boots/wraps/socks and limb constriction
There are many products on the market aimed at reducing leg fill but are any truly suitable for CPL patients? In short, if it is not medically correct compression made with short-stretch (non elastic) bandages, appropriate padding, with a gradient of compression starting over the hoof and reaching to at least the knee/hock, then no, it is not appropriate. There are very few people trained in medically correct compression for equines because it requires a foundation in human lymphology care first. Medically correct compression is tailored to the patient and requires constant adjustment and monitoring over time as the limbs begin to improve, so we can see how “off the peg” products would be highly unsuitable. The Vodder Schule is the gold standard for training.
All of these products are no doubt suitable for horses with healthy lymphatic systems or during a brief period of lymphatic insufficiency but in CPL simply have too much potential to cause further damage. Round-knit garments (they look like tube socks) can creep into the folds and cause rubs and constriction to the blood supply and lymphatics. Without the essential compression gradient they could even push the lymph the wrong way – downwards or inwards which will cause backflow and exudate or even lymphorrhea.
⭕ Increasing circulation (massage/magnets/vibration/shiatsu/etc)
It seems counter-intuitive but any therapy or product that increases blood flow to the affected area is strongly contraindicated. You can read why in the first point about Ice Therapies and the rebound effect.
“If someone is trying to sell you a product that they claim will help with CPL, ask them how it works. If it increases circulation/blood flow/arterial filtrate to the legs then it’s a no. They may maintain that it has helped CPL patients, in which case you can ask them this: “What parameters are you using to measure how it has helped over time?” To give a commentary on improvement of lymphatics, they need to be educated on equine lymphology and should therefore be able to advise on their monitoring methods. Don’t forget, that often a rapid reduction in limb size using contraindicated therapies could come back to bite you further down the line with decreased tissue quality and increased non-pitting oedema.“
Rebecka Blenntoft
⭕ Needle sticks/biopsy on the affected areas
Piercing or cutting the skin can lead to infection and exacerbation of the lymphoedema.
⭕ Obesity/being overweight/mares in foal
Simply puts too much strain on the struggling lymphatic system, increasing the risk of infection and poor wound healing. As such, obesity or pregnancy should be considered potential triggers for CPL or a cause of flare ups in the already established disease.
These may seem initially to have the desired effect by rapidly and markedly decreasing limb size however they tend to only draw the water component of oedema from the cells, leaving behind a concentrate of waste products and protein which provokes the body’s natural inflammatory response. Inflammation then leads to further oedema and fibrosis.
Chronic Progressive Lymphoedema 