FACTORS AFFECTING WOUND HEALING AND ITS COMPLICATIONS

FACTORS AFFECTING WOUND HEALING AND ITS COMPLICATIONS
Local factors –
  • Infection – It prolongs inflammation and potentially increases the local tissue injury
  • Mechanical factors – early movements or increased local pressure or torsion may pull apart the wound
  • Foreign bodies – such as sutures or fragments of steel, glass or even bone can delay healing
  • Size & type of wound influence the healing – smaller wounds or surgical incisions may heal quickly than larger excisional wounds
  • Location of the injury and character of tissue is important
    • Wound on the skin covering the bone may heal slowly as little intervening tissue prevents wound contraction
    • In tissues like pleural or peritoneal or synovial cavities, inflammation develops extensive exudates which is later resorbed and fibrosis occurs
    • In absence of necrosis normal tissue architecture is restored
Systemic factors –
  • Nutrition –
    • Vitamint C deficiency inhibit collagen synthesis
    • Protein deficiency
    • Deficiency of trace elements like Copper and Zinc
  • Circulatory status – inadequate blood supply usually impairs wound healing
  • Metabolic status – Diabetes mellitus is associated with delayed wound healing because of microangiopathy
  • Hormones – such as Glucocorticoids inhibit collagen synthesis. Their administration may result in weakness of the scar due to inhibition of TGF-β production and diminishes fibrosis
  • Age – wound healing is delayed in old age when compared to young individuals
COMPLICATIONS OF WOUND HEALING
  • Inadequate formation of granulation tissue leads to two types of complications
    • Wound dehiscence
    • Ulceration
  • Excessive formation of the components of repair process leads to formation of
    • Hypertrophic scars – accumulation of excess amounts of collagen gives rise to raised scar called hypertrophic scar
    • Keloids – scar tissue grows beyond the boundaries of the original wound and oes not regress
  • Exuberant granulation tissue – formation of excessive amounts of granulation tissue which protrudes above the level of surrounding skin and blocks re-epithelialization. It is removed by surgical excision
  • Desmoids or aggressive fibromatoses – incisional scars or traumatic injuries followed by excessive proliferation of fibroblasts
  • Contracture – exaggerated contraction of wound results in deformities of wound and surrounding structures.
    • They develop mostly in palms, soles and anterior aspect of thorax
    • Also seen in burns and may compromise the movement of joint
  • Development of Carcinoma in scars – eg squamous cell carcinoma may develop in Marjolin’s ulcer which is formed after burns in skin
References
  1. Vinay kumar, Abul K.Abbas, Nelson Fausto, Jon C. Aster. Robbins and Cotran Pathologic basis of disease. 9th edition.
  2. Harsh mohan. Text book of Pathology.8th edition.2019