Case study
Treating lymphangitis of the hind limb
Date: 23/02/16
Acknowledgements: Rebecca Crawford
Background
Lymphangitis, a swelling of the lymphatic vessels, generally in the hind limbs, has little scientific
research surrounding it and therefore can be difficult to pinpoint and treat. Also, due to the delicate
structures of the horse’s distal limbs, a fat leg is a common thing to most equestrians, with there
being several different causes; infection, trauma or foot issues being some of the many causes.
Lymphangitis has a tendency, as with most causes of chronic swelling in the distal limb, to reoccur,
which makes it a tricky condition to treat.
The lymphatic system is designed to gather liquid from the body through a series of tubes that act
like capillaries and return it to the cardiovascular system. Conversely the vessels also act as drains,
mopping up water and macromolecules from the blood system. (Sellnow. L, 2000)
When the flow of lymph through the skin is blocked, for whatever reason, the system ‘backs up’ and
the interstitial space becomes flooded causing swelling and pain response.
"Lymphangitis is a condition that results in swelling of the leg and is thought to be due to a
restriction in lymphatic flow, possibly due to a bacterial infection," Rose and Hodgson write in their
Manual of Equine Practice. They go on to say that, "Corynebacterium pseudotuberculosis has been
cultured from affected horses, but in many cases bacterial culture will be negative. Lymphangitis
sometimes occurs in outbreak form, and we have seen up to 20 horses affected in a mounted police
stable. The mode of transmission and the etiologic agent could not be established." (Rose &
Hodgson, 1999)
Within the research, it was found near impossible procure adequate samples for bacteriology,
making it difficult to find the causative agent.
As with all cases of swelling, cryotherapy and compression help in management of the condition.
When the condition progresses to ulcerative lymphangitis, where the lesions happen in the affected
area, which often ooze and leak lymph. This is believed to be caused by bacteria entering the skin, so
good stable management is very important.
Expediency is also crucial. The vet will usually prescribe anti-inflammatories, steroids and antibiotics.
Gentle exercise is also important to increase drainage within the limb. This will often be very painful
for the patient, but is necessary.
Laser therapy
Laser or red light therapy has long been used on humans to treat pain and swelling. It is effective to
treat equine lymphangitis for many reasons, it can modify the viscosity of the lymph making it easier
to ‘flow’, it also reduces the oedema, meaning less pain for the patient and enabling more
movement in the effected limb. The blue light therapy is an effect antibacterial modularity, proving
to be very useful specifically in the ulcerative lymphangitis, due to the large amounts of open
wounds on the effected limb.
Case study 1
‘Ocean’s Fury’ a 12 year old TB gelding. Has been semi-retired through arthritis of the facet joints of
the back. Has history of skin conditions. No lesions found on leg.
Owner found patient with a very filled and swollen leg out of the box in the morning. 5/5 lame on
effected limb. Vet attended patient and diagnosed ulcerated lymphangitis. Antibiotics and pain relief
were prescribed. Owner advised to walk patient for 5 minutes twice a day.
I attended patient the day after the veterinary diagnosis. Owner had cleaned and massaged limb,
removing any dead skin and excess hair. Red light therapy was applied over the entire limb, then
specific attention given around the periphery of the ulcerated wounds. Treatment time was 15
minutes in total.
Blue light therapy was also applied over the ulcers to inhibit bacterial proliferation.
The patient then received 15 minutes of red light therapy and 5 minutes of blue light every day for 5
days, alongside his veterinary treatment.
Treatment outcome
After 5 sessions of red light therapy, the hair and infected skin started to slough away, revealing
healthy pink skin underneath. After veterinary inspection, it was declared the horse was healing
exceptionally well. The lymph was draining through the skin and the oedema had lessened. The
horse was visibly less lame.
10 days post diagnosis, horse is now being turned out on hard standing daily and is 2/5 lame, with
minimal swelling in the affected limb. The skin has healed beautifully and the vet and owner are
delighted with the outcome.
Addendum
The limb, although ‘clean’ with good hair regrowth, suffered a set-back with the oedema returning. I
revisited and increased the length of treatment. Patient is now being ridden to assist in in drainage
of the limb, which works well. I have also suggested compression bandages on the effected limb at
night.
Conclusion
Equine lymphangitis is a pervasive and reoccurring condition, for reasons that are still to be fully
researched. However, this small study, and other peer-reviewed papers confirm the use of red light
therapy to assist in the healing of all skin conditions.
I have experienced excellent result using this modality for this condition. The treated skin
regenerated far faster than untreated skin I’ve witnessed previously and the vet was impressed with
how quickly the infected skin sloughed away and healthy skin showed underneath. Upon treatment
conclusion, there was new hair growth coming through the worst affected areas.
Most importantly in treating lymphangitis, the red light therapy increases the viscosity of the lymph,
making it easier to flow through the lymph vessels, assisting in the clearance of oedema and
ultimately recovery from the condition.
I would like to see more research specifically on the condition and how the red light effects the skin
at a cellular level. I would have also liked to compare several cases alongside one another to test
different treatment times and longevities.
I will be recommending and using this modality in the future for any cases of lymphangitis or
cellulitis in equine limbs.
Reference list
1. Sellnow. L, (2000), ‘Lymphangitis in horses,
http://www.thehorse.com/articles/10213/lymphangitis-in-horses, Feb 2016
2. Reuben J. Rose DVSc PhD DipVet An FRCVS MACVSc, David R. Hodgson BVSc PhD
FACSM (1999), Manual of Equine Practice, 2nd Edition, Saunders Books, UK