Soft Tissue Healing PDF

Soft tissue healing - Body adapts -- the load need to be progressive....too much or too soon = injury - Soft tissue healing is a replacement of destroyed soft tissue by living tissue. - It is necessary to understand the healing process to provide a good-suited therapy and exerci...

Soft tissue healing - Body adapts -- the load need to be progressive....too much or too soon = injury - Soft tissue healing is a replacement of destroyed soft tissue by living tissue. - It is necessary to understand the healing process to provide a good-suited therapy and exercises. - There are several stages of soft tissues healing which overlap considerably. The timeline depends on the extent of injury, what tissue is injured, individual factors,... - We will divide it in 4 phases: bleeding, inflammation, proliferation and remodeling. Bleeding phase ============== - = homeostasis phase - Aim: stop bleeding. - Usually, it last from couple of minutes to few hours (depends on injury extent, type of tissue injured, other individual factors) - Process: - The body initiates vasoconstriction (narrowing the blood vessels -- lasting few seconds to 10 minutes) and activate platelets to clot to prevent excessive blood loss. - The thrombin is released and change fibrinogen to fibrin which surrounds and stabilized the clot. Inflammatory phase ================== - Aim: to clean the wound and prepare it for growth of new tissue. - This process of inflammation is necessary to healing. - Starts rapidly within 6-8 hours after soft-tissue injury, reaching the maximal reaction 1-3 days and resolves in a few weeks (usually around 2 weeks). - 5 cardinal signs of inflammation: - Pain (calor) - Localized heat (dolor) - Redness (rubor) - Swelling (tumor) - Loss of function (function laesa) - Process: - The injury causes the necrosis (death of destroyed cells) - The injured cells release among others histamine, which starts the inflammation. - The histamine cause vasodilatation of surrounding vessels -- more blood = increased heat and more erythrocytes passing through the area = redness. - Vasodilation also increased blood flow, increase cell metabolism, local oxygen content, supply of necessary nutrients, remove waste products,... - Histamine together with other inflammatory chemicals (serotonin, cytokine, chemokine) also recruits the white cells into the injured area and make the endothelium lining of vessels more leaky (increased vasopermeability of surrounding vessels). - This allows the macrophages, other white cells and fluid to transfer from the blood to the injured area -- interstitial tissue space = swelling. - The fluid dilutes any irritation substance. - There is fibrinogen which makes a net where debris and foreign particles can be trapped. Also, hyaluronic acid and proteoglycans are released and together with fluid create a gel -- which limits local fluid flow and traps various particles and debris -- cleaning of the wound. - The swelling occurs approximately 1 hour after injury. The vessels are leakier for around 20-30 minutes after mild trauma and for much longer in more serious trauma. - If the infection is present, it will result in pus formation which will delay the healing process. - Swelling can mechanically deform nociceptors = pain - Swelling can restrict the blood flow in injured tissue space and reduce oxygen levels, increase pain, decrease function - slow down healing. - Prostaglandins released from injured cells = pain - The inflammation results in vascular and cellular response and stimulates proliferation phase. - This phase can lead to chronic inflammation -- it produces fibrous material - Can be dived in three subphases: - Acute - 3-4 days - The peak is few hours after injury. - Vascular and cellular response - Subacute - 10 -- 14 days - Macrophages do phagocytosis - Chronic - More than 1 month - In case of infection -- the cleaning (phagocytosis) in the acute and subacute phase was not enough. - Specific immune response -- B and T white cells Proliferation phase =================== - Aim: to grow new tissue (scar tissue) to fill and cover wound. - Starts 24 -- 48 hours after injury and reach its peak 2-3 weeks post injury. - Two processes: fibroplasia and angiogenesis - Macrophages (when cleaning is done) release chemicals which activates the fibroblast which migrates into the damaged area and proliferate. They are responsible also for wound contraction. - Alongside capillaries grow towards the repairing zone -- create anastomoses which repair blood flow in the area -- oxygen, nutrients, removing metabolic products, - Oxygen is necessary for collagen production -- fibroblast start to produce collagen (predominantly type III). - Granulation tissue matures -- nerve fibers ingrowth. Remodeling phase ================ - Aim: to create organized and functional scar which behaves similar to the original tissue. - Some studies claim it starts 2-3 weeks post injury (peak of proliferation); however, it seems that it starts from the first week when the new scar tissue is formed and reorganized and last for years (most changes in first 1-2 years) - The proliferation phase produces relatively weak fibrils of collagen (Type III) with random orientation -- with maturation collagen become more oriented in one line with local stress (mechanical stress is necessary). - Collagen type III is replaced by collagen type I with mor cross links and greater tensile strength. - The final strength and properties are good but probably never match the property of the original tissue (mostly said around 80% or original properties) Factors known to delay healing: =============================== - General - Age, protein deficiency, low vitamin C levels, steroids and NSAID´s, temperature (lower rate when colder) - Local - Poor blood supply, adhesion to other tissue, prolong inflammation, excessive movement, or mechanical stress (restart inflammation) Therapy ======= - We try to keep normality of this natural healing process does not accelerate it as the tissue needs time to heal properly. - Inappropriate therapy can result in inhibition of natural process and less good repair. Acute phase (bleeding and inflammatory, 1-7 days) ------------------------------------------------- - First hour avoid anything which increase blood flow (electrotherapy, ultrasound, heat). - Protection -- try to not move the segment. - Elevation and compression can decrease the swelling - Avoid anti-inflammatory and ice -- we need the inflammation to take place, it is an important part of healing. If we decreased the process the healing will take much longer and will not be so good in quality - Education: explain patient what´s happening. Tell him that he shouldn´t do anything painful otherwise the healing will be disturbed. If it is too painful take paracetamol not anti-inflammatory drugs... - Exercise - Pain free ROM (usually passive) - You can exercise the other parts of the body. - Exercise and manual therapy, electro therapy ultrasound laser can influence the chemical and mediators released -- is it needed? **Subacute** phase (proliferation, 1-3 weeks) --------------------------------------------- - The granulation tissue is formed so the wound is more stable - Exercises - Pain free ROM (also active) - Isometric strengthening to prevent muscle atrophy - Proprioceptive exercises - Exercises the other parts of body. - Some therapies can stimulate proliferation and angiogenesis. - Ultrasound, electrotherapy, shock way, laser - we can use also use physical modalities to decrease the pain, get rid of swelling, stimulate healing, activate muscles,... **Remodeling phase (3-6 weeks)** -------------------------------- - - - start to do concentric exercises. - light stretching - Functional -- neuromuscular control exercises Functional phase (6 weeks -- 6 months) -------------------------------------- - - - Can start light eccentric strengthening and slowly build us to harder exercises and plyometric (Usually the harder exercises after 12 weeks). - Increase also speed, agility, flexibility, sport specific activities. Return to competition phase (after 6 months) -------------------------------------------- - - Exercises: - avoid re-injury (maybe use brace for some time) - full ROM, full strength -- try to get to preinjury levels. - Neuromuscular coordination - Psychological readiness!!! - Pharmacotherapy - Pharmacotherapy try to add some grow factors, mediators, chemicals to normalize the process -- PRP, stem cells....so far no strong good quality evidence saying it would be beneficial in long term (Reurink et al. [](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4958098/#CR89); Reurink et al. [(https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4958098/#CR90))] References: Laumonier, T., & Menetrey, J. (2016). Muscle injuries and strategies for improving their repair. *Journal of Experimental Orthopaedics*, *3*(1), 15. [[https://doi.org/10.1186/s40634-016-0051-7]](https://doi.org/10.1186/s40634-016-0051-7) Leong, N. L., Kator, J. L., Clemens, T. L., James, A., Enamoto-Iwamoto, M., & Jiang, J. (2020). Tendon and ligament healing and current approaches to tendon and ligament regeneration. *Journal of Orthopaedic Research*, *38*(1), 7--12. [[https://doi.org/10.1002/jor.24475]](https://doi.org/10.1002/jor.24475) Punchard, N. A., Whelan, C. J., & Adcock, I. (2004). The Journal of Inflammation. *Journal of inflammation (London, England)*, *1*(1), 1. [[https://doi.org/10.1186/1476-9255-1-1]](https://doi.org/10.1186/1476-9255-1-1), Physiopedia