i.e. (Increased growth beyond size): (30-Bailey & Love 25th) (52, 1103-5-CSDT 13th) (152. S-Das 6th)KELOID SCAR is defined as excessive scar tissue that extends beyond the boundaries of the original incision or wound (As a true tumour arising from the connective tissue elements of the dermis)Keloids by definition extend beyond the border of the wounds and are most common in pigmented skin xiphisternum and each shoulder tipupregulation offibroplastic growth factors like TGF-b is implicated during hypertrophic or keloid scar formation (52 CSDT 13th)In the case of keloids, the over reactive proliferation of fibroblasts continues for weeks or months. By the time it ceases. Maturation with spontaneous improvement does not usually occursThe histology of both hypertrophic and keloid scars shows excess collagen with hypervascularityRadiographic Features:Spider leg aooearancePolycystic kidneySandy patchesSchistosmiasis of bladderCobra head appearanceUreteroceleDrooping flower appearanceEctopic ureterFlower vase appearanceHorse shoe kidneySoap bubble appearanceHydronephrosisRim or crescent signHydronephrosis* Familial condition, more common in women, Tuberculosis plays a role in aetiology* Claw like processess, pink and raised patch, unsighty often tender to touch and always itch, Recurs even when it is excisedHYPERTROPHIC SCAR is defined an excessive scar tissue that does not extend beyond inflammatory phase of wound healing and from unfavourable scar siting i.e. across the line of skin tension In the face, these are known as the lines of facial expression* Generally self limited** (Regresses after 6 months)* The last areas of a bum to heal are the most often hypertrophic* Usually no claw-like processes, no itching.* There is no sign of increased vascularity and the hypertrophic scar is never reddish in colour* It does not recur after excision. If the causative factors are eliminatedTreatment of choice for keloids and intractable hypertrophic scar is still injection of triamcinolone acetonide (1105-CSDT 13th)Comparison of Hypertrophic and Keloid scar (206-207 Sabiston 18th)FeaturesHypertrophic ScarKeloid ScarGeneticNot familialMay be familialRaceNot race relatedBlack > WhiteSexFemale = maleFemale > maleAgeChildren10-30 yearsBorderRemains within woundOutgrows wound areaNatural historySubsides with timeRarely subsidesSiteFlexor surfaceSternum, shoulder, faceAetiologyRelated to tensionUnknown