Chapter 5: Integumentary Cases

INTRODUCTION: AGING INTEGUMENTARY SYSTEM

Jill Heitzman, PT, DPT, PhD

The integumentary system plays a critical role in homeostasis and consists of the skin, superficial tissues, hair, and nails.¹ The skin is the largest organ of the body and the outward appearance of an individual that identifies one cosmetically allowing identification and body image of a person. Changes in the skin may be the first indication that an underlying pathology may be present.² Bluish discoloration (cyanosis) may indicate insufficient oxygen supply due to CVP impairments. Decreased skin turgor may indicate dehydration, redness/warmth may indicate inflammation, and hair/nail changes may indicate nutritional deficits.³ Over the lifespan, the skin becomes drier, less elastic, less perfused and vulnerable to damage from pressure, friction, shear, moisture, and malnutrition.^4,5 These changes can impact the overall function of the skin.³ Comorbid conditions such as metabolic disease, cardiovascular and peripheral vascular disease, obesity, mental health issues along with medications, all have an impact on the integumentary system and need to be considered.⁶

The skin functions as a physical barrier to microorganisms to fight against infection, prevent excessive loss of fluids, provide sensation input, and is a storage for fat and water for metabolism and thermoregulation of the body.^3,4 Resident immune cells that participate in immune processes are present in the epidermis and dermis (Langerhans cells and dermal dendritic cells). With the large surface area and network of superficial capillaries, the skin plays an important role in homeostasis and thermoregulation. The free nerve endings present in the skin allow the ability to feel pain, pressure, heat, and cold.¹ The skin functions as a thermoregulatory of body temperature through vasoconstriction, vasodilation, and sweating allowing excretion of waste products, electrolytes, and water. Synthesis of Vitamin D in skin exposed to sunlight activates metabolism of calcium and phosphates which are important to bone formation and hormonal production and synthesis. Vitamin D is also important for proper functioning of the nervous, cardiovascular, and pulmonary system. The proper amount of sunlight exposure required for synthesis of vitamin D is dependent on individual skin pigmentation, geographic location, amount of skin exposed, and time of day exposed.⁷

The structure of the skin includes a combination of elastic fibers and collagen within extracellular matrix along with the subdermal adipose padding allowing the skin to be flexible and resilient. This allows the skin to tolerate external stresses including a variety of minor daily traumas.¹ However, a disruption in the skin, either directly or indirectly as a result of underlying disease process (especially those related to malnutrition, sensory, or mobility impairments), reaction to that process or medication (steroids or anti-inflammatory medications), can increase the risk of skin injury and ultimately alter the overall health of the individual.⁸ Underlying processes can also affect the healing phases of the integumentary system: inflammation, proliferation, and remodeling, including wound bed granulation, collagen formation, remodeling of ...