Is time a great healer?
Have you ever been injured and just wanted to get better as quickly as possible? Have you ever wondered why some injuries seem to heal more quickly than others?
Wound healing is a normal biological process in the human body, and is
achieved through four specifically programmed phases:
Hemostasis
Inflammation
Proliferation
Remodeling
[See blog post'Why do I need rehab when the body heals itself?' for further details regarding the phases of healing. ]
Our bodies are made up of a variety of tissue types, each of which heal at different rates, and even respond individually to different exercises/activities (Table 1)
Table 1: Typical Tissue Healing Time Frames Itypical guidelines)
Muscle
Is the fastest healing tissue as it has a rich blood supply.
The circulatory system provides all tissues with nutrients and oxygen needed for tissues to heal.
Following a programme devised of specific targeted exercises gets the muscles contracting, which stimulates blood to flow through the muscle tissue, encouraging health and healing.
Tendons
[attach muscles to the bones] Tendons generally have a more limited blood supply than muscles. This means they are somewhat slower to heal than muscles.
Blood supply to injured tendons can be stimulated by activities that cause tension on the tendon tissue. A mix of loading and stretching the tendon tissue can have beneficial effects, current research suggests that both eccentric and concentric tissue loading can have positive effects on improving tendon health.
Bones
Bones react well to progressive weight bearing activities, as they heal best when loads are applied to them. As this stimulates an increase in bone growth at the injury sites and in turn an increase in bone strength.
This concept is why it is more common to see an individual wearing an ‘air cast’ boot rather than a plaster cast. Allowing patients to walk while protecting their healing bone allows the bony repair process to occur faster and more effectively than keeping weight entirely off of a fracture site.
Ligaments
[attach bones to other bones]
They generally have a more limited blood supply than either muscle or tendon – lengthening their healing time!!
For any type of ligament injury, protecting the injury site is important while the tissue is healing. Yet, at the same time, motion at the injured joint is desired, to help promote blood flow so that healing occurs. In order to allow motion while protecting the ligament, some sort of bracing is often utilised.
Cartilage
Cartilage is avascular, meaning that it has no blood supply! And also aneural – meaning that it has no nerve supply!
What does all this mean? Well, the lack of blood flow in cartilage means that healing time is very slow. Also the lack of nerve endings means that the cartilage doesn’t emit the same pain signals to the brain when we injure it. Pain is normally felt, when a secondary tissue is irritated/injured, because the bodies movement mechanics have adapted due to the affected cartilage.
Nutrition to the cartilage is supplied by fluid within the joint, helping to lubricate the tissue. The lubrication process occurs by a sort of flushing mechanism i.e. when load is applied and then removed from the tissue. Because of this, lack of movement or weight bearing can cause thinning of cartilage, making it susceptible to injury.
This is why, even fairly immediately after injury, exercises will be encouraged to enable to joint to move throughout their range of motion to encourage healing.
Nerves
Nerves send signals from your brain to your muscles, allowing movement. Nerves also send messages towards the brain, relaying information from muscles, skin, and joints about temperature, pressure, pain, body position, and body movement.
Nerve healing proceeds at a very slow rate, which is why the process requires patience and persistence. However, it is possible to adapt exercise programs, therefore allowing patients to participate in normal activities whilst in the background continuing to promote the health of the healing nerve tissue but following an appropriate program of rehabilitation.
What biopsychosocial factors can affect tissue healing time?
Age
Although the elderly can heal most wounds, they have a slower healing process, and all phases of wound healing are affected (Gerstein, et al., 1993). The inflammatory response is decreased or delayed, as is the proliferative response. Re-modeling occurs, but to a lesser degree, and the collagen formed is qualitatively different (Ashcroft, Horan & Ferguson, 1998)
Physiological and Psychological Stress;
Over Training
Excessive exercise can result in disturbances to the homeostasis of multiple body systems (neurologic [nerves], endocrinologic [hormones], immunologic [immune system], in turn affecting the healing process, resulting in longer healing times.
Psychological Stress
A substantial delay in wound healing can occur as the stress response suppresses the inflammatory and proliferation phase of wound healing, causing a significant delay in the healing process (Gouin & Kiecolt-Glaser, 2011).
Alcoholism
Short-term rapid onset of alcohol exposure supresses the bodies natural inflammatory response [the first phase of healing], therefore resulting in a significant increase in would healing time (Jung, et al. 2011).
The most significant impairment seems to be in wound angiogenesis [formation of new blood vessels required for growth and development of new tissues] , which is reduced by up to 61% following a single exposure to alcohol.
Smoking
Post-operatively, patients who smoke show a delay in wound healing and an increase in a variety of complications such as; infection, wound rupture, anastomotic leakage [a surgical connection fails and contents leak], wound and flap necrosis [death of the wound tissue occurs], epidermolysis [fragile, blistering skin], and a decrease in the tensile strength of wounds (Silverstein, 1992).
Nutrition
Together with fats, carbohydrates are the primary source of energy in the wound-healing process. Glucose is the major source of fuel used to provides energy for angiogenesis and the laying down of new tissues.
Protein is one of the most important nutrient factors affecting wound healing. A deficiency of protein can impair wound remodeling, and can also affect the immune system which can result in an increased risk of infection to the wound site (Wild, et al. 2010).
How can we help you?
Getting started on an appropriate program of rehabilitation can considerably speed the process of recovery and minimize activity limitations – allowing maintenance of optimal musculoskeletal health. Contact us today to discuss your treatment journey.
References
Ashcroft, G. S., Horan, M. A. & Ferguson, M. W. (1998) ‘Aging alters the inflammatory and endothelial cell adhesion molecule profiles during human cutaneous wound healing’. Lab Invest. Jan;78(1):47-58 [Online]. Available at https://pubmed.ncbi.nlm.nih.gov/9461121/
Gerstein, A. D., Phillips, T. J., Rogers, G. S. & Gilchrest, B. A. (1993) ‘Wound healing and ageing’, Dermatol Clin, Oct;11(4):749-57 [Online]. Available at
https://pubmed.ncbi.nlm.nih.gov/8222358/
Gouin, J. P., & Kiecolt-Glaser, J. K. (2011). ‘The impact of psychological stress on wound healing: methods and mechanisms’. Immunology and allergy clinics of North America, 31(1), 81–93. [Online]. Available at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3052954/
Silverstein P. (1992) ‘Smoking and wound healing’. Am J Med. Jul 15;93(1A):22S-24S. [Online]. Available at https://pubmed.ncbi.nlm.nih.gov/1323208/
Jung, M. K., Callaci, J. J., Lauing, K. L., Otis, J. S., Radek, K. A., Jones, M. K., & Kovacs, E. J. (2011). ‘Alcohol exposure and mechanisms of tissue injury and repair.’ Alcoholism, clinical and experimental research, 35(3), 392–399. [Online]. Available at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3117956/
Wild, T., Rahbarnia, A., Kellner, M., Sobotka, L. & Eberlein, T. (2010) ‘Basics in nutrition and wound healing’, Nutrition, vol. 26, no. 9. pp 862-866 [Online]. Available at https://www.sciencedirect.com/science/article/abs/pii/S0899900710001668