Tag Archives: aging

What Can Different Types of Facial Wrinkles Tell Us?

Few people enjoy having wrinkles. Some people spend a lot of time, money and efforts trying to reduce the wrinkles on their face, while others simply appreciate them as something naturally occurs with aging. Regardless, wrinkles are always associated with aging. However, if we look into what different types of wrinkles are and how they form, we will find that not all wrinkles are bad. Not all wrinkles are caused by aging, and not all wrinkles should be treated the same way. Here, we introduce different types of facial wrinkles categorized by plastic surgeon and their corresponding treatment.

A person smiling that shows some wrinkles on her face.
The wrinkles created by the motion of smiling are dynamic wrinkles. They will disappear once the smile stops. Credit: Masterfile.

In general, there are two main types of wrinkles, dynamic wrinkles and static wrinkles. Dynamic wrinkles are the type of wrinkles that only appear when you make expressions such as smiling, laughing, or frowning. These wrinkles disappear once your expressions stop. The facial muscles have enough elasticity to return to their original positions. These are temporary wrinkles that everyone may have, even little kids!

Static wrinkles, on the other hand, are wrinkles that form when your muscles cannot return to their original position due to gravity and loss of collagen and elastin. These wrinkles cannot disappear like the dynamic wrinkles. When the collagen fibers become thinner, the skin loses elasticity and gets more wrinkles, whose width and height grow with age. (Lemperle, 2001) Lemperle et al. from the University of California put these wrinkles into three categories.

Three hand-drawn figures that show textures of different wrinkles.
Figures that show the textural change of skin experiencing (a) superficial wrinkles, (b) mimetic wrinkles, (c) folds. Source: A Classification of Facial Wrinkles.

The first type is superficial wrinkles. These are the less severe wrinkles that only involve textural changes of the skin surface. These wrinkles lines are separate lines at first but will gradually group together. (Arumugam, 2015) Common causes are aging, excessive exposure to UV light, and gravity. Superficial wrinkles, according to Lemperle, can be reduced or removed by chemical peeling (applying chemical solution on the face to peel off the top layer and then grow it back), or laser resurfacing. (Lemperle, 2001)

A figure with 2 side-by-side photos that show the effect of laser resurfacing before and after the treatment. The wrinkles of the person's face reduces.
Before and after laser resurfacing. Credit: Tahoe Aesthetic Medicine.

The second type is mimetic wrinkles. These are more severe and visible dermal creasing. Major causes include aging and repeated dramatic facial expression. (Arumugam, 2015) Because the facial creasing is deeper, the reduction methods include more complicated procedures such as muscle resection (cut out a portion of muscle and inserted the shortened muscle at the same place), botulinum toxin (a neurotoxic protein), or skin filler injection. (Lemperle, 2001)

The picture shows a person's lower half of the face with dash line indicating where the nasolabial line is. A needle is pointing at the dash line mimicking the process of skin filler injection.
Skin filler injection to reduce the effects of nasolabial lines. Credit: Filling in Wrinkles Safely

The last type is folds, the part of the face where droopy skin overlaps. Folds and mimetic wrinkles usually occur together. To correct the overlapping skin, tightening procedures such as blepharoplasty (surgery that repairs droopy eyelids), face lift, or skin excision are needed. (Kligman, 1985)

Noticeably, researchers have discovered that wrinkles formation may be different by gender, race, etc. For example, women in general have finer and less apparent wrinkles than men because their skin is thinner and softer. (Wu, 1995) Asian skin connects more firmly to the tissues underneath because of its thicker dermis and higher collagen density. Therefore, the repetitive pulling of the skin surface affects wrinkles on Asians and Caucasians differently. (Ahn, 1999)

Wrinkles are nothing horrible. They are something that everyone has or will have in the future. There is nothing wrong with wanting to reduce the wrinkles on your face, either. Just remember that there are many types of wrinkles and each of them requires a bit of a different treatment. Spending some time finding the appropriate treatment will most likely save you more time, money, and effort in the future.

Sources:

[1] Lemperle, Gottfried, et al. “A Classification of Facial Wrinkles.” Plastic and Reconstructive Surgery, vol. 108, no. 6, 2001, pp. 1751–1752., doi:10.1097/00006534-200111000-00050.

[2] Arumugam, P, et al. “Facial Forehead Wrinkles Detection using Colour based Skin Segmentation.” Advances in Natural and Applied Sciences, Aug. 2015, pp. 71–80., doi:10.22587/anas.

[3] Kligman, A.M., et al. “The Anatomy and Pathogenesis of Wrinkles.” British Journal of Dermatology, vol. 113, no. 1, 1985, pp. 37–42., doi:10.1111/j.1365-2133.1985.tb02042.x.

[4] Wu, Yin, et al. “A Dynamic Wrinkle Model in Facial Animation and Skin Ageing.” The Journal of Visualization and Computer Animation, vol. 6, no. 4, 1995, pp. 195–205., doi:10.1002/vis.4340060403.

[5] Ahn, Ki-Young, et al. “Botulinum Toxin A for the Treatment of Facial Hyperkinetic Wrinkle Lines in Koreans.” Plastic & Reconstructive Surgery, vol. 105, no. 2, 2000, pp. 778–784., doi:10.1097/00006534-200002000-00050.

Pressurized Vessels Supporting the Spine: Structure and Function of Intervertebral Discs

Back in 1989, it was estimated that about 2.5 million U.S. workers suffered from low back pain, and low back pain has even been talked about as one of the largest causes of disability in the world. Intervertebral disc degeneration is one of the most common reasons for low back pain in adults. In order to understand how disc degeneration occurs and causes pain, it is important to examine the structure and function of discs in the back.

Computer generated image of a healthy lumbar spine
Vertebral Column: Obtained from Smart Servier Medical Art

Discs are structures that sit in between vertebrae in the spine (blue in the image). Their consistency has been compared to Jell-O and the seemingly mythical product called the waterbed. This consistency comes about because of the microstructure of the discs. The main structural component is collagen which not only surrounds the discs but also traverses across the fluid-filled center to give support. Collagen is found all over the body in places ranging from bones to eyes. There are many different types of collagen that are able to account for the softness of the cornea and the strength and stiffness of bones. In discs in the back, the collagen that traverses the middle is the same as that found in cartilage, while the collagen that makes up the outer layer is the same collagen found in skin and bones. This gives the discs a strong, thin outer layer surrounding the gel-like center, warranting the comparison to the waterbed.

Because of this structure, intervertebral discs provide support for the spine in compression. The spine can be compressed by activities as simple as carrying a backpack, sitting, or bending over. When these and other activities occur, the vertebrae press in on the discs, causing pressures from about 15 to 300 psi, or pounds per square inch, depending on the activity. For reference, the recommended tire pressure for a car is 30-35 psi and the pressure inside a champagne bottle is 60-90 psi.

As discs degenerate, either with age or trauma, they respond differently to the large compressive stress applied from the spine. With age, this change in response is most commonly attributed to the inside portion of the disc drying up and changing from a gel to a solid. Discs rely heavily on fluid flowing through their pores, and once they dry up, this no longer occurs. As loads are applied, instead of increasing pressure, degenerate discs can expand outward creating a phenomenon known as a bulging disc. While this is just one of the many medical problems a degenerate disc can cause, it is

Computer generated image of a lumbar spine with disc herniation.
Disc Herniation: Obtained from Smart Servier Medical Art

common and typically leads to an increase in pain. When the discs expand outwards, it reduces the space between the vertebrae causing irritation. If the discs expand far enough outward, they can leave the space between the vertebrae, entering the region where many nerves lie, potentially causing pain throughout the body.

Despite their odd consistency, intervertebral discs play an important role in the spine, sometimes pressurizing to more than 3 times that of a champagne bottle. Both injuries and natural degeneration leads to negative changes in the biomechanical properties of discs, causing an increase in back pain. If you are interested in learning how to take care of your discs, worried you have an injured disc, or simply want to learn more, I recommend going here.

Runner’s Knee: Knee Pain Isn’t Just for Old People

Don’t knee problems only plague old people or people who have run for a lifetime? I questioned this when, for the seventh time in a row, my knee was hurting only a mile and a half into my run. I’m too young for this! However, a plethora of information suggests that knee pain is perhaps not so uncommon in younger runners and athletes as I thought.

The American Family Physican published an article detailing one form of knee injury informally called “Runner’s Knee”. A shockingly high number, between 16 and 25 percent, of running related injuries fall into this categorization. Medically termed patellofemoral pain syndrome (PFPS), the ailment manifests in pain or stiffness in the knee, particularly when bent in load-bearing scenarios such as walking, running, jumping, or squatting. The patellar region experiences shocking loads even in the day to day: in walking alone the region experiences up to a half the person’s body weight while in an activity like squatting it can experience up to seven times one’s body weight. Often the pain is hard to pinpoint but occurs in or around the front of the knee within a circular range. It can inhibit or put a stop to training, however, if addressed early on, can often be healed or corrected much more quickly.

an animated image of a runner mid-stride with the pain region for patellofemoral pain syndrome highlighted
Photo by www.scientificanimations.com from Wikimedia Commons

In PFPS, the patella (the kneecap) moves abnormally within the groove on the end of the femur (called the femoral trochlear groove) due to imbalanced or unusual loads on the joint. This results in over-stressing the joint and causing pain. Several possible causes exist for PFPS; here, I will focus on three of most commonly cited: increased intensity of activity, weak hip muscles, and overpronation.

an image of the muscular and skeletal structure of the knee, including the patella
Photo by BruceBlaus on Wikimedia Commons

Increased Activity

One review explored that women are more likely to suffer from PFPS. In this study they saw that women of higher activity levels were not necessarily more likely to experience pain due to PFPS than women who had a lower activity level. Rather, a substantial increase in activity level seemed to be the cause of pain. Therefore, more than overuse of muscles or joints, PFPS often develops with increased amounts of activity, or temporary overuse, such that the body is not prepared to handle the increased and repetitive forces on the knee.

Weakness in Hip Muscle Strength 

This study shows that lower extremity mechanics and motion can be affected by hip strength. For example, inward rotation of the hip can be lessened through strengthening of hip muscles that counteract that rotation. With less internal hip rotation, the knee abduction moment (the tendency of the knee, due to reaction forces from the ground, to rotate  inward and away from the balanced midline of the knee joint) decreased which often resulted in less stress in the knee. Therefore, the review suggests that strengthening hip muscles can lower the patellofemoral joint stress and help treat PFPS. 

Overpronation

Pronation refers to the natural movement of one’s foot and ankle slightly inward while stepping. When the ankle rotates too far inwards, it is called overpronation. Overpronation can lead to further improper structural alignment in the lower body as the tibia rotates improperly in response to the ankle rotation. The tibia’s rotation then disrupts the natural movement of the patellar joint and can contribute to PFPS. In many cases, overpronation can be corrected through use of orthotic shoe inserts that prevent the over-rotation of the foot and ankle.

In conclusion, while we may often associate knee problems with older people or arthritis, PFPS affects many athletes, particularly runners, at any age. Often, proper training programs that do not accelerate activity too quickly, strengthening exercises that focus on the hip muscles, and proper, overpronation-correcting footwear can treat or prevent an individual from being affected by PFPS. Check out some strengthening exercises here.

The Study of Snoring is Anything but Boring

Here we take a deeper look about that noise that plagues some of our family members, our roommates…or even ourselves!

Elderly man sitting in the sun, asleep with head back and mouth open.
Photo by Stephen Oliver on Unsplash

What Causes You to Snore in the First Place?

The human upper airway contains anatomical parts that are membranous, meaning they lack support from cartilage. Some parts include the tongue, the soft palate, and the tonsillar pillars. A lack of cartilaginous support enables these parts of the airway to be susceptible to vibrations.

Anatomical diagram of the human upper airway.
Modified from Huang, Quinn, Ellis, and Williams, “Biomechanics of Snoring,” from Endeavor, 1995.

During sleep the upper airway muscles relax and cause the size of the airway space to decrease, resulting in airflow limitation and turbulence.

Whenever we inhale, the turbulent flow through the relaxed airway causes those membranous structures to vibrate and produce a sound most commonly known as snoring.

A Brief Mechanical Explanation of Snoring

Examining snoring in the view of mechanical systems, respiratory noise is created by the oscillation of the upper airway with the air passing through it. This oscillation is indicative of an issue with flow instability (turbulent flow) over a flexible structure (the relaxed airway).

An experiment was created to model the movement of the soft palate during snoring, where a piece of wood was used to simulate the hard palate and a piece of leather simulated the soft palate. The leather and wood were attached to each other inside of a rigid tube that was connected to a pump (meant to model the lung inspiration).

During inspiration, the leather flap oscillated until it reached its full amplitude. Upon reaching the maximum amplitude, the leather flap hit the wall of the tube and created a noise known as palatal “flutter”. This palatal flutter is the most common method of noise production in humans: snoring.

Is Snoring Something to Be Concerned About?

Young woman waking up in the morning, appearing tired.
Photo by Kinga Cichewicz on Unsplash

Approximately 44% of men and 28% of women are habitual snorers.

Snoring can be a symptom of obstructive sleep apnea, a condition distinguished by snoring and breathing that is labored by repetitive and obstructive gasps.

The fragmented sleep resulting from sleep apnea can lead to decreased energy and poor attention and concentration. Sleep apnea can also be related to vascular issues like hypertension and its prevalence appears to increase in people over 65 years of age.

What Are Some Remedies to Snoring?

Remedies for snoring range from noninvasive devices to invasive surgical procedures.

The surgical option to remedy snoring involves removing a portion of the vibratory tissue from the back of the upper airway. For those people wanting to avoid surgery, non-invasive solutions include the use of nasal strips to lift and open the nasal passages; experimenting with sleep positions other than sleeping on the back; or using oral appliances and nasal continuous positive airway pressure (nCPAP) to prevent the tongue and soft palate from collapsing into the upper airway. Losing weight, avoiding smoking and alcohol can also help to reduce snoring.

There are also resources for snoring in kids, as well as additional home remedies and surgical information regarding snoring.

Below is a great animated video which gives an introductory explanation to snoring.

Muscle Loss Due to Aging

It is a well-known fact that as we get old, our bodies (sadly) deteriorate, leaving us unable to perform certain physical functions as easily as we could have when we were younger. In this article, the authors describe a study done to analyze muscle loss due to aging, primarily by examining two different age groups of humans. By conducting measurements on people over and under the age of 40 years, results show a clear difference in muscle mass and strength between the two.

Karsten Keller and Martin Engelhardt conducted their study on 14 adults under the age of 40 and 12 adults over the age of 40. They measured the circumference (size) of each leg of the participants in four different locations at 10 and 20 cm above the knee, and 10cm below it along with the largest circumference position below the knee. In addition, they conducted strength tests based on the motion of the leg at 30˚ and 60˚ from resting sitting position using the Dynamometer BIODEX® System 3.

Man Lifting Weights
Photo by Sopan Shewale on Unsplash

Results given in the article can be viewed in full here, but as a summary both the overall size and strength of legs was stronger in the younger participant group than in the older group. According to the authors, we as human beings generally are at our physical peak throughout the 20-30 year age range. From analyzing their own experimental results, Keller and Engelhardt conclude that our muscle mass generally begins to decline after about 40 years of age. The factors that contribute to the size and strength of our muscles declining due to aging is varied and complex, but one reason for our weakening is that as we age our muscle fibers decline in number. Once enough fibers are lost, our bodies experience apoptosis, or the destruction of cells. Anabolic hormone decrease, risk of disease, appetite loss, and declining of physical activity are all other large factors attributed to muscle loss in aging.

Maximum isometric strength of the left leg in 60° flexion of both groups.
Maximum isometric strength of the left leg in 60° flexion of both groups.

Maximum isometric strength of the right leg in 60° flexion of both groups.
Maximum isometric strength of the right leg in 60° flexion of both groups.

Human beings get old, and physically, it is not that great. Our muscle strength and size decline due to a number of factors. However, we can help ourselves fight physical aging by paying attention to our health, specifically maintaining some physical strength training and ensuring we receive nutrients to feed our muscles. The authors recognize the limitations of this study, including small sample size and desiring ages from every decade; however they are able to conclude by stating that their data shows that muscle declines after 40 years of age in a range from 16.6% – 40.9%. To learn more about some causes of muscle loss through aging, such as sarcopenia, inactivity, and physiological changes check out these articles.