A horse owners worst nightmare! A fat, swollen leg. Horses are so good at injuring their legs it’s untrue. If you own a horse, you'll have to deal with a swollen limb at some point. Swellings aren't just found on legs though, horses and dogs love to fall over and bruise themselves. Swelling after injury is acute inflammation that can persist and become chronic if it's not dealt with correctly.
Swelling is the body responding to injury: pain and damage is detected by the nervous system and the body responds by increasing blood flow to the area and allowing the blood vessel walls to become more permeable. This allows white blood cells, proteins and other nutrients to reach the damaged tissue to start healing. With this, a lot of water and fluid also accummulates in the area. Swelling is the body trying to heal the injury but it's often a very dramatic and over the top response! This large amount of fluid in the area is normally more of a hinderance than a help.
So what should you do about swelling? The first point of call is to assess the extent of the injury and how much pain your animal is in. You might need urgent veterinary attention for anti-inflammatory medication. (Please note this protocol is for swelling only and not for open wounds). When the injury is less than 48 hours old, the oldest and still most effective remedy is the application of a cold source. Ice pack, cold water pack or cold hosing reduces the blood flow to the area and therefore the swelling. Cold therapy also effects the tissue chemistry by lowering the amount of inflammatory proteins therefore helping to reduce the pain from inflammation. Cold therapy should only be applied for 10 minutes at a time with enought time for the tissue to fully warm up before re-applying. Over use of cold therapy can cause further damage to the tissue and after 10 minutes blood flow is actually increased rather than decreased (why we go red after being in cold winds or rain after a while).
At first a compressive but breathable bandage could be applied if the location allows it. Also, a veterinary physiotherapist could apply pulsed electromagnetic field therapy (PEMF) to help reduce blood flow to the area. This is very effective in reducing initial swelling, giving pain relief and can work for up to 4 hours after the treatment has finished. This is more effective than cold therapy but may not be accessible for daily use- speak to your vet physio for information on this. The combined use of these therapies gives the best results.
After the first 48 hours, the injury has become chronic in terms of the stages of inflammation. At this point you need to increase blood flow to help remove the stagnant fluid in the swelling. If you continue to decrease the blood flow, you will reduce the amount of nutrients reaching the injury site and removal of waste which will increase the time the wound takes to heal. So weeks and weeks of cold hosing and ice packs might be causing the injury to take longer to heal!
If the injury permits, gentle walking will help circulate blood in the body and help reduce the swelling. Movement really is key to help the body regain normal function. Again the use of pulsed electromagnetic field therapy (PEMF) can help, as the setting can be changed to then help increase the blood flow. It also increases the production of growth factors that help the tissue repair so actively helps with the healing process.
Therefore, the first couple of days are crucial to help the reduction of swelling but after that should we be doing less? It's important to rest the injury and keep exercise limited to gentle walking and call your veterinary physiotherapist to help by applying PEMF. The days of cold hosing for hours may be over!
Cheing, G. L., Wan, J. W., & Kai Lo, S. (2005). Ice and pulsed electromagnetic field to reduce pain and swelling after distal radius fractures. Journal of rehabilitation medicine, 37(6), 372–377. https://doi.org/10.1080/16501970510041055
Daanen H. A. (2003). Finger cold-induced vasodilation: a review. European journal of applied physiology, 89(5), 411–426. https://doi.org/10.1007/s00421-003-0818-2
Kowel MA., (1983) Review of Physiological Effects of Cryotherapy. The Journal of Orthopaedic and Sports Physical Therapy Vol. 5(2):66-73
Kubat, N. J., Moffett, J., & Fray, L. M. (2015). Effect of pulsed electromagnetic field treatment on programmed resolution of inflammation pathway markers in human cells in culture. Journal of inflammation research, 8, 59–69. https://doi.org/10.2147/JIR.S78631
Liu, M., Lee, C., Laron, D., Zhang, N., Waldorff, E.I., Ryaby, J.T., Feeley, B. and Liu, X. (2017), Role of pulsed electromagnetic fields (PEMF) on tenocytes and myoblasts—potential application for treating rotator cuff tears. J. Orthop. Res., 35: 956-964. https://doi.org/10.1002/jor.23278
Vieira Ramos, G., Pinheiro, C. M., Messa, S. P., Delfino, G. B., Marqueti, R., Salvini, T., & Durigan, J. L. (2016). Cryotherapy Reduces Inflammatory Response Without Altering Muscle Regeneration Process and Extracellular Matrix Remodeling of Rat Muscle. Scientific reports, 6, 18525. https://doi.org/10.1038/srep18525
Stewart, GM, Wheatley-Guy, CM, Johnson, BD, Shen, WK, Kim, C-H. (2020) Impact of pulsed electromagnetic field therapy on vascular function and blood pressure in hypertensive individuals. J Clin Hypertens. 22: 1083– 1089. https://doi.org/10.1111/jch.13877
Wang, Z. R., & Ni, G. X. (2021). Is it time to put traditional cold therapy in rehabilitation of soft-tissue injuries out to pasture?. World journal of clinical cases, 9(17), 4116–4122. https://doi.org/10.12998/wjcc.v9.i17.4116