Hypertrophic Scar Lecture Notes PDF

Hypertrophic scar DR/Dina Mahmoud Nabeeh lecturer of physical therapy Horus university Definition It is lumpy collagen or fibrous tissue that stay within the boundaries of the original wound due to exaggerated proliferative response to wound healing. It occurs within 4: 8 weeks post wo...

Hypertrophic scar DR/Dina Mahmoud Nabeeh lecturer of physical therapy Horus university Definition It is lumpy collagen or fibrous tissue that stay within the boundaries of the original wound due to exaggerated proliferative response to wound healing. It occurs within 4: 8 weeks post wound infection or wound closure with excess tension or excess wound contraction. It has rapid growth phase up to 6 months. Gradually regress over a period of few years (mature flat scar with no further symptoms).  Incidence: Factors affecting scar formation Incidence: 40: 70 % post-surgery. 91 % post burn. : Factors affecting scar formation 1. Age: more in 2nd : 3rd decade due to ↑↑ blood supply → ↑↑ the rate of collagen production and ↑↑ the skin tension and wound contraction. 2. Location: more in anatomic locations with high tension lines such as neck, shoulders, pre-sternum, knees and ankles. 3. Depth: ↑↑ the depth → ↑↑ the scar formation, so the deep partial and full thickness burn develop more scar than superficial and superficial partial burn. 4. Race: more in darker skin Keloid scar: Is a firm, smooth, hard growth due to spontaneous scar formation. It can arise soon after an injury, or develop months later. Keloids may be uncomfortable or itchy and extend well beyond the original wound. They may form on any part of the body, although the upper chest and shoulders are especially prone to them.  HYPERTROPHIC SCARRING KELOIDS INCIDENCE 40 %to 70% following surgery , 6 %to 16% in African populations Up to 91% following burn injury PREDILECTION SITES Shoulders, neck, pre-sternum ,knees and Anterior chest, shoulders, earlobes , ankles upper arms and cheeks TIME COURSE Within four to eight weeks Within years after minor injuries or Following wounding spontaneous formation on the mid-chest Rapid growth phase for up to six in the absence of any known injury. months, then regression over a period of Persistence for long periods of time. a few year No spontaneous regression APPEARANCE Do not extend beyond the initial site of Project beyond the original wound injury margins. HISTOLOGICAL CHARACTERIS-ICS Primarily fine, well-organized ,wavy type Disorganized, large, thick, type i and iii iii collagen bundles oriented parallel to Hypocellular collagen bundles with no epidermis surface with abundant nodules or excess myofibroblasts nodules containing myofibroblasts and Poor vascularization with widely plentiful acidic mucopolysaccharide scattered dilated blood vessels Scar assessment: 1.Objective scar assessment: Pliability Cutometer: non-invasive suction device that apply –ve pressure on the scar and then measure its vertical deformation. Tonometer: non-invasive device that provides constant deformation force via 200 gm weight exerting a constant +ve pressure / cm² of scar. The tissue pliability is measured by the amount of tissue deformation (depression of the tissue by the effect of weight). Color: By chromameter, mexameter and tristimulus colorimeter, as these devices uses spectrophotometric color analysis to calculate erythema and melanin index. Perfusion: By laser doppler perfusion imaging that measure the amount and movement of RBCs in the skin and subcutaneous tissue that helpful in determining burn depth. Thickness: By ultrasound scanner: the head of device send inaudible high frequency sound waves into the body and then listen for the returning echoes from the tissues in the body. Firmness: By durometer: that apply vertically load on the scar to measure scar firmness. Surface area and volume: Planimetry: measure the surface area of the scar. Linear method: by disposable ruler that measure the maximum length and width of the wound and then calculate the surface area by multiplying the maximum length and maximum width. Tracing method: by transparent metrigraph paper that positioned on wound and then draw the wound margins on the paper and then measure the maximum length and width of the wound by the ruler and then calculate the surface area by multiplying the maximum length and maximum width. Three-dimensional topography: by capture the scar surface to measure the scar volume.  Subjective scar assessment scales: Vancouver Scar Scale (VSS): Patient and Observer Scar Assessment Scale (POSAS): Visual Analogue Scale (VAS): Stony Brook Scar Evaluation Scale (SBSES):  Scar treatment: 1.Pharmacological treatment: 1.Steroid Injections Direct corticosteroid injection into a hypertrophic scar or keloid, which reduces inflammatory process, break the bonds between collagen fibers that may reduce scar size and increase its pliability.  Physical therapy treatment: 1.Silicone gel sheeting: Mechanism: Affects the hydration status of the scar and cause occlusion to the scar (↓↓ the water vapor transmission rate and ↑↑ the accumulation of the fluid under the sheet), so it ↓↓ the capillary activity, ↓↓ hyperemia and ↓↓ the collagen deposition. Application: Starts 2 weeks after wound healing and applied either twice daily or 12: 24 hours / day for 6: 12 months. Side effects of silicone gel sheeting: Skin itching, skin rash, skin breakdown and bad smell from the gel. Pressure garments: Mechanism: ↓↓ blood supply to the scar tissue → hypoxia → ↓↓ O2 and nutrients to the scar tissue → ↓↓ collagen production → balance between collagen synthesis and lysis. Mechanical compression on the scar tissue → accelerate the remodeling phase → accelerate the realignment of collagen bundles that already exist in more organized manner. Application: Recommended if wound closure ˃ 10: 14 days or if the wound require grafting and can be applied as soon as wound healing. Apply for 23 hours / day for more than 6 months. The garment should be changed every 12 hours with careful cleaning of the garment. Side effects of silicone gel sheeting: Skin itching, skin rash and skin breakdown. N.B: Pressure ˂ 10 mm Hg. → accelerate remodeling phase. Pressure 15: 25 mm Hg. → optimum pressure for optimum benefits. Pressure ˃ 40 mm Hg. → skin breakdown and paresthesia. Deep friction massage: It is specialized type of massage (cross massage or transverse massage) aims to breakdown the adhesions and realign the collagen in more arranged regular pattern so, it increases scar pliability. Application: The area to be treated should be in stretched position. The PT places two or three fingers over the scar or adhesion. Enough pressure should be applied to blanch the scar (make it white with pressure). But don’t apply too much pressure to avoid skin damage. The therapist moves their fingers perpendicular (at right angles) to the scar. The fingers and the underlying tissue should move together. The massage should feel deep and uncomfortable but not painful. The treatment should be applied 30 minutes 3 sessions per week for 8 weeks. Hydrocortisone Iontophoresis: It is transdermal transfer of ions (drugs) by the application of small direct electric current. The iontophoresis technique is dependent on the general principle that like charges repel each other so, when we use Hydrocortisone as a potent corticosteroid drug (negative polarity), we should use the (negative electrode) as an active electrode and should be positioned on the scar site. The other passive (positive) electrode was placed at any point away from the active one at a sufficient distance. The drug was transferred to the skin from the negative pole. For efficient drug transmission: The dosage of 40 mA/min. should be used. Direct current intensity was ranged from 3-5 mA (2 mA). Duration of 20 minutes. 3 sessions per week. 12 weeks. Thank you