What are factors that impair tissue repair?

Systemic or local, intrinsic or extrinsic Infection (delayed healing, prolongs inflammation and increases local injury) Diabetes (compromises repair, abnormal wound healing systematic) Nutrition (protein malnutrition and vitamin C deficiency inhibit collagen synthesis retard healing) Steroids (anti-inflammatory, weak scars result) Mechanical factors (increased local pressure or torsion cause wounds pull apart (dehisce)) Poor perfusion (athersclerosis or DM or varicose vein) Foreign bodies (steel, glass, bone) Type of injury, location of injury