Sock It to Me! Good Footwear Starts with Good Socks
Socks are high on the list of things we take for granted. Whether it's for orthotic patients or for ourselves, we often select socks without giving the choice much thought, and yet the lowly sock can make a huge difference to its wearer's comfort, attitude, and safety-not to mention short- and long-term health, say footcare experts.
Logic and experience, not to mention studies by the U.S. military and other clinical researchers, document the protective effect of hosiery on the feet of patients with diabetes and arthritis. Negative consequences that can develop or be exacerbated by wearing the wrong sock include yeast, bacterial, viral, and dermatophyte infections, friction blisters, kyperkeratoses, capsulitis, bursitis, calcaneal fat pad atrophy, tailor's bunion, and sunungual hematoma, to name a few.
But while there is a bewildering array of new styles, fibers, and knits available-the result of a 1980s boom in sock research and development-Dennis Janisse, CPed, president and CEO of Milwaukee, Wisconsin-based National Pedorthic Services, notes that there is no helpful field guide to sock selection.
"When I started in pedorthics we talked about the foot, the foot orthosis, and the shoe-but that other barrier wasn't really discussed," Janisse says. "Now we have an exciting number of options with many different properties-moisture-wicking capabilities, a sock inside of a sock to decrease shear and friction inside the shoe, [and] socks with extra cushioning and padding.
"I was involved in a study with diabetes patients who had ulcers that wouldn't stay closed, and arthritis patients who had been fit with shoes and foot orthoses but still had issues," he continues. "The extra-cushion socks were just fantastic; they made a big difference in survival of the foot for the diabetes patient and comfort for the arthritis patient."
Moisture is the enemy and, due to the presence of more sweat glands per square inch than any other part of the body, feet perspire a great deal, says Elliott Crooks, a footwear consultant at the Denver, Colorado, Foot Solutions store. Active perspiration in the foot area can cause maceration between the toes and some of the undesirable conditions listed earlier.
Unfortunately, one of the most widely held misconceptions about socks is that cotton socks are the best choice for dealing with that moisture problem, both for normal and neuropathic feet, our experts report.
James R. Christina, DPM, director of scientific affairs for the American Podiatric Medical Association (APMA) says, "It was thought for a long time that cotton socks were best, but there have been several studies that have shown that while cotton socks absorb moisture well, they don't wick it away from the skin, so there's actually an increase in blisters with the cotton sock. Several published papers and studies have confirmed this point."
Crooks calls this "The Great Middle School Athletic Department Unconscious Conspiracy"-one that encourages students in organized sports activities to buy cotton athletic socks because they're cheap and easy to launder. This habit stays with most wearers for life.
When cotton gets damp, Crooks points out, it loses its strength, its cushioning flattens out, it stretches, wrinkles, folds, and loses its insulation value.
"A study done in the Cascades looked at appropriate types of clothing to wear in rainy, windy conditions at about 40 degrees. It essentially concluded that if you were caught wearing a cotton sweatsuit, you'd be warmer if you stripped it off and ran like hell, since the amount of water it would absorb and hold against you would pull more heat off than the environmental conditions!"
Crooks also notes that cotton has a significantly shorter lifespan than synthetic fabric; it becomes more abrasive and deteriorates with each wash-wear cycle.
More durable blended-synthetic fibers absorb less while wicking the moisture away from the skin, so they maintain their cushioning even when conditions are moist and humid.
"While natural fibers like cotton are popular and claim to 'breathe,'" says David B. Higgins, consulting vice president at Dr. Comfort, Mequon, Wisconsin, "fiber construction of specially designed synthetic fabric is much healthier and will last longer. The best and most durable fibers are acrylic and COOLMAX® polyester."
By wicking away moisture and keeping the foot dry, the right socks can prevent problems with a hot, moist environment that breeds fungus and bacteria, Janisse agrees.
"As the interface between the foot and shoe or orthotic, the sock needs to perform as well as possible-so fiber choice is obviously important," Crooks says. "Acrylics and polyesters are very good at not absorbing moisture but helping it to move away from skin. COOLMAX is probably the best of them because where most fibers are essentially round in cross-section, COOLMAX is X-shaped in cross section, and that additional surface area increases the efficiency of moisture transport. Thermax® polyester is a hollow tube that makes it very warmth-efficient. Silk, in comparison, comes out of the silkworm as flat ribbons, so it's exceptionally heat-efficient because it reflects heat back to the body."
Wool, too, remains an excellent sock fiber choice-one that retains its structure, insulation value, and cushioning while absorbing moisture. It's the most efficient choice for cold, wet conditions, but check the tag to be sure it's merino wool, which is bred for softness, Crooks advises. Processed properly, merino wool is also non-allergenic, as well as comfortable in a synthetic/wool blend sock.
Newcomer fibers like bamboo have also become popular, partly because of their soft, porous nature, silky texture, excellent breathability, moisture-wicking capability, and also because, as online advertising touts, bamboo is naturally sustainable and renewable, uses virtually no pesticides or fertilizers, yet it can grow as much as 36 inches per day-absorbing 35 percent more carbon dioxide than a typical oak tree while it grows.
Janisse mentions other new approaches in the marketplace; for example, a sock with mohair woven into the footbed can provide exceptionally high anti-shear, anti-friction value. "Some manufacturers are actually weaving Teflon® fibers into the sole of the sock for the same reason-to cut down shear and friction inside of the shoe. Shear friction contributes to blisters, callusing, and even...ulcers.
"Some are weaving silver and copper into the socks to utilize their antifungal and antibacterial properties. This goes back to the time of the pharaohs, when Egyptians used copper pipes to transport water because of its ability to keep the water cleaner."
Like bamboo, copper and silver are woven into the sock and won't wash out like a spray or coating; they're there until the sock wears out, Janisse says.
Weave can also play a significant role in a fiber's performance, Crooks points out. Polyester fibers that are arranged in a tight, flat knit-as in the 1970s leisure suits, dress shirts, and blouses-don't breathe. When blended into polar fleece, however, it's a totally different story.
He cites high-tech design techniques that are producing socks with efficient combinations of knit patterns, as well. For example, he says the SmartWool® Adrenaline sock features "extra cushioning under the toe and heel, ribbing around the arch for added support, lighter mesh over the top for greater breathability, a different mesh where the foot transitions into the ankle for more efficient flex, and vertical ribbing to hold up the top cuff."
Although white socks are favored for wear by patients with neuropathic issues, as they more readily reveal any blood or discharge from wounds that might otherwise remain undetected, colors and patterns are becoming increasingly popular.
"The belief held by a few older patients-that dye can leach out of a colored sock and potentially be harmful if you have any type of foot problem-is a misconception," Christina notes. "Today's dyes are greatly improved...."
"Color isn't the only way socks can be fun," says Crooks, whose personal favorite socks depict Godzilla destroying Tokyo. "For someone who's depressed about having to give up pretty shoes for something that's far more comfortable but 'orthopedic'-a fun sock can be a real morale booster."
Fit Is Essential
While the variety of fibers and designs are helping to reshape the sock industry, even a sock of ideal fiber and design can be hazardous to the wearer's health if the fit is wrong, Higgins points out.
"Socks are close fitting garments, 'intimate,' so fit is crucial," he says. "Good fit will improve compliance, protection, and value. Socks that try to fit more sizes of feet with fewer sizes of socks are almost always inferior, regardless the price or...fabric content. Look for socks that offer at least four sizes, from small to extra large, fitting no more than 2.5 shoe-size ranges with each.
"If the socks are loose, it can be uncomfortable in your shoe and, more importantly, dangerous to the insensitive foot, due to hot spots from pressure. If the sock is tightly fitted, it can inhibit circulation. Loose fit or tight fit will also cause the sock to wear out more quickly, so price is not the true measure of long-term value. Finding socks that are anatomically shaped to the foot and leg will fit best and last longer.
"The density [thickness] of socks is also an important feature; too thick can cause shoe fit compromise, too thin provides no protection against friction and shear," Higgins continues. "Padding in just the right places under the foot is best."
For normal, healthy but aging feet, a certain amount of strategic padding can be a plus, Christina points out. "Some people have a loss of the protective fat padding on the ball of the foot; that's kind of a natural thing as we age.... Thorlos® and similar socks with a bit of extra padding in that area can be helpful."
Fred Bernhardt, vice president of Comfort Products, Croydon, Pennsylvania, adds, "If the pedorthist has gone to all the work of evaluating what footwear the customer should have, they don't want a thickly padded or cushioned sock. If you're in a custom-molded shoe with a custom orthotic, that is not required. They're looking for ways to offload pressure in the custom-molded shoe, and if they put on this padded sock, it might actually do more damage than good."
Crooks agrees, and points out that sock thickness can change shoe fit by a full size. With a heavier, more cushiony sock, go with a half-size to a full-size larger shoe; if the shoes are custom-made, select a thinner sock-like the one the wearer chose for his or her original shoe fitting.
Just like with shoes, Crooks cautions, "You need to know how particular [sock] brands run. Different manufacturers will tend to run large or small."
He also warns that using thickly cushioned socks for their thermal value in cold outdoor environments can achieve the opposite effect."For warmth, you need good circulation, so not necessarily a snugger sock, as cultural wisdom dictates. Wearing heavy socks for more warmth may take a comfortable fitting shoe or boot and turn it into a snug fit. That impacts the circulation and sets you up for cold toes."
The correct approach, Crooks continues, particularly if the customer's footwear fits tightly, is to go with a thinner sock. "Make more room within the footwear so there's no restriction on circulation."
Janisse points out the added risk of overly snug socks to patients with diabetes. "I have seen patients who have gotten ulcerations or sores because they have a pair of shoes that was fit for a nylon or...thin sock, but then they switched to a sock with extra cushioning because it was identified as a diabetic sock-and they think that means it's a better choice for them. If the patient doesn't have any sensation and they begin wearing a sock that doesn't give them enough room inside of the shoe, it actually could...cause more problems than it's supposed to be fixing."
Higgins reassures diabetic patients with venous conditions that they need not give up compression hosiery because of the constrictive dangers, however. "Keep the compression in the 15-20mmHg range, and only wear medically correct compression socks made by FDA-registered brands. Always ask your healthcare provider!" he says.
Relative to appropriate sock fit, he lists seams or toe closure as another critical area, especially for diabetic or insensitive feet. "Hand-linked seamless is best, but other forms may be acceptable if carefully checked."
Bernhardt also addresses the importance of seamless socks when he discusses the special needs of neuropathic patients.
"My father and I have manufactured prosthetic socks for 37 years; we realized that a lot of the new amputees we served were derived from the diabetic population," he says. "Providing an amputee sock is a reactive response, so we decided to focus more on the proactive side by developing diabetic sock products."
He explains that diabetic socks incorporate two main features: a low compressive top, snug enough to hold the sock in place, but not tight enough to constrict bloodflow; and no seam in the toe area, which eliminates "the potential for irritating and damaging toes in a manner that might not be detected by persons with diabetes who...have a loss of sensation."
From the first terry sock that was cushioned throughout from top to toe, to a sock with a seamless toe in both standard and extra-wide profile, designs have evolved to include a sock within a sock, which absorbs friction between the layers of fabric rather than between the foot and the single layer of sock within the shoe.
"People forget that the neuropathically involved foot does not perspire," Bernhardt says. "Sometimes folks tend to get quite involved on whether you have this wickability-and for the neuropathically involved foot, that's really a moot point.
"The problem is, there's no one sanctioning body-no one out there that says this is the perfect sock. There are groups of pedorthists, doctors, etc., that seem to think they have a better idea of what the right sock is. It's becoming fairly confusing for both the wearer and the manufacturer."
Higgins agrees. "After having started the very first diabetic sock brand in 1994," he says, "I have watched this industry grow to be over $200 million and still growing. I am still alarmed by the false claims and poor quality of products that circulate the market, simply to keep their cost low. This is true in shoes as well as socks. When it comes to 'at risk' feet, hopefully our industry will take a much closer look at what we put next to the skin of our customers/patients."
Judith Philipps Otto is a freelance writer who has assisted with marketing and public relations for various clients in the O&P profession. She has been a newspaper writer and editor and has won national and international awards as a broadcast writer-producer.