Lesson 1, Topic 1
In Progress

Changes in Anatomy, Physiology, and Diseases of the Integumentary and Musculoskeletal Systems

April 11, 2024

Learning Objective: Examine the changes in anatomy, physiology, and diseases of the integumentary and musculoskeletal systems.
      TABLE 30.3 summarizes the changes to the integumentary and musculoskeletal systems and what can be done to promote healthy aging. The following sections provide more detail about the changes to those systems.


Integumentary System
Learning Objective: Explain the changes in the anatomy and physiology of the integumentary system caused by aging.
      The skin is the body’s first line of protection against infection, and it also is responsible for preventing the loss of body fluids and regulating body temperature. Changes in the appearance and function of the integumentary system are usually caused by a combination of ordinary age-related changes and environmental factors, especially the amount of sun exposure over time. Exposure to ultraviolet light from the sun frequently is the cause of the following skin conditions:
                • Wrinkles
                • Age spots
                • Blotches
                • Leathery, dry, loose skin
      All of these conditions are associated with aging. Changes caused by the ultraviolet light from the sun or by the normal aging process can affect all three layers of the skin: the epidermis, dermis, and subcutaneous tissue.
      The cells in the epidermis reproduce more slowly as people age, and this slower regeneration causes the skin to appear thinner. The skin becomes more prone to tearing and blistering. The risk of infections increases, the healing process takes longer, and older people are more susceptible to bruising. Because the skin can be easily torn, it is important to be very careful when performing phlebotomy or covering a wound on an older patient. The use of tape should be avoided. Vitamin D synthesis, a major function of the epidermis, significantly declines in aged skin, and a decrease in the number of melanocytes increases photosensitivity.

      The dermis loses 20% of its mass during the aging process, resulting in the paper-thin or transparent skin seen in older adults. The number of collagen cells in the dermis also declines with age, causing the skin to sag and wrinkle. Because both sweat and sebaceous glands decrease in number, aging people have difficulty tolerating higher temperatures because they perspire less. At the same time, the blood supply to the dermis decreases; this makes it difficult to regulate the body temperature and leads to an increased susceptibility to both hypothermia and heat stroke in aging individuals. Any situation in which an older adult would be exposed to extremes of cold or heat should be avoided. Make sure a blanket is available in the examining room if the air conditioning is on. Ask patients if they are too cold or too hot and take the necessary steps to make the patients feel more comfortable.
      Atrophy of the subcutaneous layer increases the skin’s susceptibility to trauma, so patients bruise much more easily. The skin is denied natural lubrication, and dry skin is one of the most common complaints among older people. In addition, fat deposits increase in the abdomen in men and in the abdomen and thighs in women as they age.
      Here are some suggestions that might help older people to prevent and treat dry skin:
                • Use a room humidifier to moisten the air
                • Bathe less frequently and use warm rather than hot water
                • Use a mild soap or cleansing cream (e.g., Aveeno, Basis, or Dove)
                • Wear protective clothing in cold weather
                • Moisturize dry skin
      Pain receptors are distributed throughout the skin. Because of age-related changes in the receptors, older people have a higher pain threshold. They may not notice a cut or burn as quickly as a younger person would, so a more serious burn may occur before it is noticed. In addition, wound healing becomes a problem because of decreased blood flow to dermal tissues.
                Other changes occur in the skin’s appendages. Hair changes in color, growth, and distribution. Hair grays because of the decreased rate of melanin production and the replacement of pigmented hair with nonpigmented hair. Women lose hair on the trunk and have increased facial hair. Although alopecia (loss of hair) is caused by an inherited trait, aging also causes hair loss. Hair on the eyebrows and in the nose and ears becomes coarser and longer in men. The nails of older people take longer to grow and are more brittle. Nails, particularly toenails, thicken as a result of trauma or nutritional deficiencies. It is not unusual for nails to split, making them more susceptible to fungal infections.
              Seborrheic keratoses, usually referred to as “age spots,” are one of the most common benign skin disorders found in the aging population. They appear as waxy, scaly papules that vary from tan to dark brown (FIGURE 30.3) and typically are found in areas of sun exposure, such as the trunk, back, face, neck, extremities, and scalp. They are not dangerous but may be removed for cosmetic purposes.
      Shingles is another condition that shows up on the skin. It is caused by the same virus that causes chickenpox. A person who has had chickenpox in the past is at risk of developing shingles.


Shingles Risk Reduction
The varicella-zoster virus causes both shingles and chickenpox. After an active chickenpox infection, the virus lies dormant in a nerve dermatome. As people age, their risk increases that the virus will reactivate, causing the formation of blisters and varying degrees of pain along the affected nerve pathway. It is estimated that 1 in 3 adults will develop shingles in their lifetime. There is currently one shingle vaccine approved in the United States.
      Shingrix reduces the risk of shingles. Shingrix is a recombinant vaccine that also boosts immunity against the varicella-zoster virus. This vaccine is administered as an intramuscular injection. It is recommended that the two doses should be given 6 months apart. This vaccine is recommended for healthy adults 50 years and older. The two doses are 90% effective at preventing shingles and postherpetic neuralgia.
      For individuals who develop shingles even though they were immunized, the duration of symptoms is shorter. The vaccine is recommended even if an individual has had shingles in the past to help prevent future occurrences of the disease.
A shingles vaccination can be quite expensive ($200 to $300). Therefore, it is important that the patient or the medical assistant first check with the individual’s insurance carrier to see whether the injection is covered.

FIGURE 30.3  Seborrheic keratosis. From Habif TP: Clinical dermatology: a color guide to diagnosis and therapy, ed 6, St. Louis, 2016, Mosby.

30.3 Critical Thinking Application
Rose Deluca, a 71-year-old patient of Dr. Martin, is unhappy about the changes in her skin that have occurred in the past several years. Based on what Bill knows about the normal changes that occur in the skin as people age, how can he explain these changes to Mrs. Deluca, and what can he suggest to help with dryness and other typical aging changes?

Musculoskeletal System
Learning Objective: Explain the changes in the anatomy and physiology of the musculoskeletal system caused by aging.
      As the body ages, changes in the muscles, bones, and joints affect the individual’s appearance, strength, and mobility. The extent of change depends on the person’s diet, exercise pattern, and heredity. Cartilage loss and degeneration, which produce osteoarthritis, commonly occur in the weight-bearing joints of older people. Joint range of motion is affected, and the intervertebral disc spaces are decreased, causing loss of height as a person ages. A breakdown in joint structures may lead to inflammation, pain, stiffness, and deformity.


Suggestions for Helping the Older Adult with Mobility, Dexterity, and Balance Problems
                • Encourage the person to use assistive devices, such as adaptive silverware, a tub seat or shower chair, electric razor, and reaching devices.
                • Assist the person with gripping devices as needed (wait for the patient to place their hand around a cup or help them with it before letting go).
                • Provide older adults with enough time to complete tasks independently.
                • For a post-stroke patient who is ambulatory but has one weak side, use a gait belt when transferring the patient from a chair to an examination table.
                • The provider may recommend physical therapy for range-of-motion exercises.
                • Encourage activity approved by the provider; lack of activity results in a decline in the ability to function.
      Aging brings a decrease in the strength and speed of muscle contractions in the extremities but only a slight decline in overall muscle endurance. Muscular changes in the aging patient are directly related to the individual’s activity level. Research shows that musculoskeletal disease is not an inevitable result of the aging process; however, 40% to 50% of women over age 50 have a serious problem with bone demineralization. Men also experience bone loss but at a later age, and a much slower rate than women.


Osteoporosis
Osteoporosis is the primary cause of hip fractures, which can lead to a loss of independence and complications that ultimately can end in death. The spinal vertebrae also can collapse, producing the stooped posture associated with “dowager’s hump.” Sometimes bones break because of the sheer weight of the body on them. Often people say they fell and broke a bone when in reality, the bone fractured, causing them to fall. Multiple factors contribute to the development of osteoporosis, but it is most common in postmenopausal women. Risk factors for osteoporosis include the following:
                • Female gender (women have a five times greater risk than men)
                • Thin; small-boned frame
                • Family history of osteoporosis
                • Estrogen deficiency before age 45, either from early menopause or oophorectomy
                • Estrogen deficiency resulting from an abnormal absence of menses (eating disorders, excessive aerobic exercise, fibrocystic ovaries)
                • Racial background (Caucasian and Asian women have the highest risk)
                • Aging
                • Extended use of anticonvulsant drugs, prednisone, and excessive thyroid hormone medications
                • Sedentary lifestyle, smoking, excessive alcohol intake, and lack of calcium and vitamin D when growing up
Weight-bearing exercises and calcium and vitamin D supplements are recommended to prevent demineralization of the bones. A number of medications are used to prevent or treat osteoporosis:
                • Alendronate (Fosamax) and risedronate (Actonel), which reduce the rate of demineralization
                • Raloxifene (Evista) and ibandronate (Boniva), which slow bone thinning and cause some increase in bone thickness
                • Denosumab (Prolia, Xgeva), an injectable medication that helps increase bone mass
                • Teriparatide (Bonsity, Forteo), a daily injectable medication to increase bone density and decrease the risk for fractures.
Another option is an intravenous (IV) medication, zoledronic acid (Reclast), for the once-yearly treatment of postmenopausal women with osteoporosis. Reclast helps increase bone density in the spine and hip, thus reducing the risk of fractures.


Falls
The risk of injuries from falls increases with age; falls cause the greatest number of injuries in people over age 70. Aging individuals are at greater risk of falling because of sensorimotor changes in vision and mobility, osteoporosis, and cerebrovascular accidents (CVAs). Falls in older patients usually result in fractures because a large percentage of these individuals have osteoporosis. Serious fractures, such as those of the hip, require the patient to be immobile for extended periods, and this opens the door to a wide range of debilitating complications:
                • Pressure injuries
                • Pneumonia
                • Placement in long-term care facilities
                • Even death
      Falls are largely preventable. The medical assistant can play an active role in helping family members and patients become aware of risk factors and safety measures. Here are some suggestions that can help patients prevent falls:
                • Have regular vision tests.
                • Understand the side effects of medications, especially those that cause vertigo.
                • If you experience orthostatic hypotension, rise slowly and stand still for a moment with support before moving.
                • Limit the use of alcohol.
                • If needed, consistently use assistive devices, such as a cane or walker, for support.
                • Wear low-heeled, rubber-soled shoes with good support.
                • Avoid going outside in icy weather.
                • Engage in regular weight-bearing exercise for muscle and bone strength.
                • Keep hallways, stairs, and bathrooms well lit.
                • Assess the home for possible danger areas, remove throw rugs, use handrails on steps and grab bars in bathrooms, and keep emergency numbers handy.


30.4 Critical Thinking Application
The family of Rita Schaeffer, a 73-year-old patient, is concerned about the risk of falls. Mrs. Schaeffer recently was diagnosed with osteoporosis, and she lives alone. What information should Bill give the family to help them prevent accidents in their mother’s home? Also, Mrs. Schaeffer’s 45-year-old daughter is concerned about developing osteoporosis. What steps should the daughter take to prevent the disease?