Tag Archives: arthritis

Electric knee implants could help millions of arthritis patients

An answer could be on the horizon for millions of people living with arthritis after scientists have found a way to repair joints using electrical implants. The implants work by producing a current every time the person moves their joint to regrow the protective cartilage that cover the ends of bones .

Bioengineers from the University of Connecticut developed a biodegradable mesh implant, about half a millimeter thick, which generated tiny electrical signals to repair arthritic joints in rabbits. The study, published in Science Translational Medicine, saw the team successfully regrow cartilage in rabbits’ knees without using potentially toxic growth factors or stem cells. Crucially, the cartilage that grows back is mechanically robust, with further plans to trial the implant in larger animals and humans.

In their white paper, the team states that although more work is needed to improve the scaffold, this study provides evidence that biodegradable implants that produce electricity independently can use exercise to treat arthritis.

No cure for arthritis despite tens of millions of sufferers

According to the CDC, 58.5 million people currently have arthritis in the United States, which costs the American people $303.5 billion annually. While there are treatments, arthritis technically has no cure.

It is a widespread and painful disease caused by damage to joints formed between the body’s bones. One of the subtypes of this disease, called osteoarthritis, attacks the cartilage at the end of bones in the joint. As this buffer deteriorates, bones begin to rub against each other so that everyday activities like walking become agonizingly painful – making the growth of new cartilage highly desirable. 

Sufferers face years of pain without surgical or pharmaceutical intervention, but these treatments can only slow down the damage instead of repairing damage to the joint. However, even this process involves taking healthy cartilage from the patient or a donor and comes with inconveniences and risks.

Therefore, regrowing healthy cartilage in the damaged joint itself would be very helpful. Some researchers have investigated chemical growth factors to induce the body to regrow it; other attempts rely on a bioengineered scaffold to promote tissue growth. But, neither of these approaches works-even in combination-with the regrown cartilage breaking under the everyday stresses of the joint.

Your joints can generate electricity to heal you

The new breakthrough involves a tissue scaffold made out of poly-L lactic acid (PLLA) nanofibers, a material often used to stitch surgical wounds that dissolve after the person heals. The scaffold produces a little burst of electrical current when squeezed in a process known as piezoelectricity. In this case, the joint’s regular ‘squeezing’ is provided by walking, which generates a weak electrical field that encourages cells to colonize the implant and grow into cartilage.

“Piezoelectricity is a phenomenon that also exists in the human body. Bone, cartilage, collagen, DNA, and various proteins have a piezoelectric response. Our approach to healing cartilage is highly clinically translational, and we will look into the related healing mechanism”, says Dr. Yang Liu, a postdoctoral fellow in Nguyen’s group and the lead author of the published work.

Nguyen’s group implanted their scaffold in the knee of injured rabbits. After a month in recovery, the rabbits were encouraged to walk for 20 minutes a day on a slow-moving treadmill to exercise their legs and generate the electric current. The charge encouraged the regrowth of fresh, mechanically robust cartilage, making the knee as solid and functional as before it was injured. Whereas rabbits treated with nonpiezoelectric scaffold and exercise treatment still had a hole in this protective sheath and limited healing.

In an interview with New Scientist, Thanh Nguyen, an assistant professor in the department of mechanical engineering, says, “If used in people, the material used to make the implant would dissolve after about two months – although it could be tweaked to make it last longer.”

What next for this promising implant?

Nguyen states that the results are exciting but cautions that further tests need to be carried out on larger animals that bear more similarities to humans.

His lab now plans to observe the treated animals for 1-2 years to ensure the cartilage is durable and wants to test the PLLA scaffolds in older animals as arthritis usually affects the elderly. He concludes by saying that if the scaffolding helps older animals heal, it indeed could be a bioengineering breakthrough.

Recovering from a torn meniscus? Here’s five things you should know

Having and maintaining an active lifestyle is one of the joys of life. It’s both a necessary part of our physical health and a great stress reliever to help with the darker, gloomier days.

When we work out and get those reps in, there is always a risk of some kind of mechanical mishap with our bodies. Maybe we stepped in wrong. Maybe someone fouled us on a field. Maybe our decades of bad posture and sitting had to lead us to an incorrect pattern of movement that cascaded to an injury.

Whatever the case, the risk we take on is always just a bit less than the benefit we extract from being active. In the event that we do get injured, there has to be a time period for calmness, recovery, and a full regaining of health so that we can get back to the field once again.

Among the most common injuries in sports and life, in general, is a torn meniscus. That injury is no joke. There is a whole spectrum with varying degrees of severity when it comes to a torn meniscus. Here, we will explore everything we need to know as well as how to implement a treatment plan, i.e. which knee brace for meniscus tear injuries. The braces themselves have varying tiers of use, as you’ll come to find.

Here are the 5 things you should consider while making a full recovery:

What and where is the meniscus?

knee-animation

The first thing we have to address is what the meniscus actually is in relation to the entire leg complex. In order to do so, we’ll have to go over some basic anatomy.

The knee is classified as a “hinge type synovial joint.” This means exactly what it sounds like. It’s a hinge that primarily moves in a given range of motion that allows for flexion and extension.

There’s a reason why the leg doesn’t bend other ways. It’s locked into the range of motion similar to a door. It can move to the point (flexion) where the calf muscles hit the hamstring—like an open door and move back to the straight position (extension) you observe while standing, like a door closing.

The “synovial” part means that the cartilage parts glide on a lubricated surface allowing for smooth motion throughout. So in essence, it’s a very well oiled mechanical lever that allows your body to move through space seamlessly. The main parts of the knee are:

  • The tibia and the articulating surface of the tibia, covered in cartilage.
  • The femur and the articulating surface of the femur, covered in cartilage.
  • The patella that serves as your knee cap.
  • The ligaments that hold the structure together in a multi-directional criss-cross fashion.

A meniscus is a crescent-shaped fibrocartilaginous anatomical structure that, in contrast to an articular disc, only partly divides a joint cavity. Credit: Wikimedia Commons.

So where is the meniscus? The meniscus is in between the tibial and femoral articulating surfaces and serves as shock absorbers. This is why when you run properly, you normally don’t feel the jolt or bone crashing into the bone. You’ve got two menisci (plural form of meniscus) per knee joint:

  • One of the outer portions called the lateral meniscus
  • One of the inner portions is called the medial meniscus.

Every time you move the leg, the meniscus is in action. When you play any sort of sport or perform any kind of multi-directional movement, the meniscus acts to soften the blow to the knees and re-orient you and your body position in order to maintain balance.

This function is also known as proprioception and is mediated by little units of the nervous system that work independently from conscious thought. The menisci also serve as an attachment to a bunch of different ligaments. The entire complex is meant to work as a single, consistently firing unit. When something goes wrong down there and you can feel it upon impact or stepping down onto a surface, more often than not, it has to do with the menisci in one way or another.

How do I know I have a meniscus tear?

A meniscus injury can manifest itself in a whole bunch of ways. It’s a pretty sturdy structure, similar to a cushion on either side of the knee joint at the tibial end, so injuring it takes some strong movement or some odd angles. Any time you rotate your knee rapidly or forcefully twist your leg at the knee, you run the risk of tearing your meniscus. The question is, how would one know if they have a meniscus injury? Here are a few telltale signs.

Popping

Knee popping is also described as clicking or snapping. It’s usually experienced by people who use their legs a lot like athletes and lifters. You can hear a popping noise when you either flex or extend the knee. That’s the basic sign. Now, this might not always mean you have a torn meniscus, but the gradual increase in sound, intensity, and even pain can provide a key insight into a possible tear. Another reason for knee popping and pain might not be a torn meniscus at all, but crepitus (cartilage irritation) caused by arthritis.

Swelling

Swelling is a common catch-all inflammation indicator. It means something down there isn’t going as well as it is supposed to. If you’re experiencing swelling, there will be, more likely than not, some pain involved. The swelling, in turn, will limit your mobility a bit. It may not be super pronounced. It could just feel like it’s a bit bigger than it is supposed to be coupled with some extra heat radiating from the center of your knee. This is usually the point at which people become more concerned.

Decreased Mobility

This is pertaining to any sort of movement you might normally be able to carry out. This means straightening your knee fully. This may also mean the inability to twist or rotate your knee due to either pain or stiffness. These are all classified under the umbrella of decreased mobility.

If you’re experiencing one or more of these, you should see a doctor as soon as you can. Knee injuries, especially meniscus tears can progress and become worse. These are best treated when you get to a doctor early on. The treatment plan will be much more effective and you’ll recover much faster. Of course, the doctor is going to rule out things like arthritis. If this happens, you might have a completely different set of treatments. Remember, the knee is a fairly complex mechanical joint.

How bad can it be?

A meniscus tear can be either lateral or medial. That is, it’s the meniscus towards the midline of your body or the one on the outer side. In order to determine which side it is on, and what degree of injury you have, the recommended diagnostic tool is an MRI. An MRI is a noninvasive procedure that can visualize various structures that are inside your body. Once you get that done, a doctor can determine what the grade for your meniscus tear is. Here are the various degrees of damage and what they mean to you:

  • A grade 0 on the MRI you don’t have a tear at all. If you’re experiencing similar pain, it may be attributed to a different disorder or movement pathology. Either way, it isn’t your meniscus.
  • A grade 1 is a minor tear that manifests itself in slight pain and some swelling. It’s often reported as just a minor nagging pain in the knee during flexion. You’ll most likely be told to ice it and let it rest.
  • A grade 2 is a significant tear that may not need surgery. There’s definitely pain involved. But people with a grade 2 tear can often walk around and still get to point B if they need to.
  • A grade 3 tear is where things start to get squirrely. A grade 3 tear is a prime candidate for any surgery. Arthroscopic surgery is the most common approach here. A grade 3 tear is also known as a “true” tear. It means there’s definitely a partial or full detachment of the meniscus from either the bone or separation in the cartilage center.

The different types of a torn meniscus

The type of tear is also important when a professional is determining the course of action. There are 6 common ones:

  • Your intrasubstance/incomplete tear is often a sign of early degeneration. It’s considered a “stable” injury in that you can most likely heal up without having invasive surgery. They’re seen in the middle of the cartilaginous mass on either the lateral or medial side.
  • You’ve got your radial tear—the most common of the tears. It’s a tear right up the middle of the crescent-shaped meniscus structure in the part where there aren’t any blood vessels around. That last part is important because it’s easier for an anatomical structure to heal if there’s vascular supply. Doctors typically go in with the arthroscope and delicately remove the damaged part.
  • The Horizontal tear is the biggest candidate for meniscal repair. It’s a tear along the line of fibers that make up the meniscus. When doctors see this, they typically try and sew it back together. Out of all the injuries that need invasive intervention, this is probably the most agreeable in terms of patient comfort and outcome.
  • If you’ve got a flap tear, you’re looking at a fairly uncommon and unusual pattern of the tear. It’s where a piece of the top portion of the meniscus is partially torn like a soda tab. Surgeons usually just remove that piece without any sort of damage.
  • A complex tear means it’s a tear that changes direction in the meniscus. It’s treated like two tears in one. In these cases, your doctor’s next move can be anything. It really depends on the severity, the direction, and the nature of the tear. They can remove the whole thing or just repair it like a horizontal tear. Either could be on the table.
  • The strangest one by far is the bucket tear. It’s when there’s a tear near the center of the meniscal mass and it’s pulled out in the other direction, creating a bucket handle look. This one is a cause for mediating medical attention and should be repaired and treated as soon as possible.

Knee braces and recovery for a torn meniscus

Recovery from any of the kinds of meniscal injuries requires some very basic principles. You need to give it some rest, you need to alternate between cold and hot, and you need to be patient.

If you’re an athlete, it may be tempting to go back in right away, but know that resting and letting the meniscus fully heal is an investment in your future ability to play.

You should also have a brace. What kind? In this case, you need special rehabilitative knee braces, specifically a knee brace for meniscus tear like those from PowerRebound.

These come in a variety of shapes, but what you want is a hinged brace that limits extension and movement. Your knee needs to heal, above all else. It’s not necessary to keep the patella in place, so a cover may or may not be used. But as long as it’s slightly tighter than you think it should be, and a bit more rigid than you might want it. It’s less about the overall comfort and more about giving it uncompromising stability while it’s in the healing overs.

Remember, cartilage and joints receive nutrients indirectly. Unlike major organs where there are vast networks of blood vessels constantly exchanging nutrients to the target cells, cartilage receives its nutrients through a barrier layer. It then diffuses slowly into the rest of the particle mass. Because of this, healing is often slow. If the doctor says you need 8 weeks of lessened mobility and a lot of rest, throw on that brace and order one book. You’re going to be doing a lot of sitting.

Meniscus tears are not fun, but they happen. Sometimes, they come at the most inopportune time, like in the middle of an important game. Don’t worry too much about it. It’s not a life-threatening or career-ending injury. It can get worse and it can cause some problems down the line. But if you get it treated immediately and find your preferred knee brace and recovery therapy, you’ll be up and about in no time.

Knee Replacement Surgery For Torn Meniscus

If you’re experiencing pain in the knee and difficulty straightening your knee fully, particularly the area around the knee cap and your knee’s outside edge, you may consider knee replacement surgery. The good news is that there are several options available to help alleviate or prevent further damage to your knee, helping you return to active daily living in as little as six weeks.

One type of surgery involves repairing the tears in the cartilage between the knee’s outer surface and bone. While the damage is not as severe as it is with a torn meniscus, there are still significant benefits to repairing the cartilage between your knee and bone. This can provide better protection against future tears and also help minimize the amount of time it takes for arthritis to take hold.

Surgery may also help eliminate swelling in your knee. Because the cartilage of the knee is damaged, the bones cannot properly cushion the joint. The result is often swelling and pain in the area of the knee. While this can occur on its own, it’s a common part of aging and occurs more in older people.

While a torn meniscus is usually associated with the development of arthritis, it’s possible that your condition is caused by another problem, such as a dislocated kneecap or a bone spur that’s not healed. In this case, the surgery will treat the cause of the damage and allow for the repair of the knee. The pain and swelling will disappear, along with any swelling or stiffness you experience.

If you decide that knee replacement is the best option, you should make sure to get the surgery done only by a professional who has extensive experience performing the procedure. Also, take note that knee replacement surgery recommended for torn meniscus may be dependent upon the cause and severity of your injury and your current health.


Knee arthritis has doubled since 1950, and we don’t really know why

Aging and obesity alone cannot explain it.

 

Arthritis is an inflammation of the joints (or another area where the bones come together). It’s often a chronic condition which typically starts off in the hands or feet, and most often ends up affecting the knees. It’s estimated that one in five Americans over 45 suffer from knee arthritis, and similar figures are reported in many parts of the world.

Initially, this was thought to be a consequence of aging — people lived to older ages, and therefore started suffering more from “old age diseases.” Obesity is also thought to play a role — the more you weigh, the more pressure you put on your joints. But a new study found that these factors alone cannot explain the rise in knee arthritis prevalence.

Stretching my knees

Image credits: BruceBlaus.

Ian Wallace is a paleoanthropologist at Harvard University who studies how human health and diseases have changed over time. He was aware that knee arthritis is often associated with obesity and aging, but wanted to see how these and other factors affected the prevalence of obesity through the years. So he and his colleagues studied several thousand American skeletons, from pre-industrial, early industrial, and post-industrial periods. They were specifically looking at the wear and tear in the skeleton’s knees. The age and body mass index were also assessed and through statistical processing, the impact of obesity and age was removed.

Wallace and colleagues found that 18 percent of the skeletons from the post-industrial ages (1950) had signs of advanced arthritis, compared to six and eight percent of the early industrial and prehistoric bones, respectively. The statistical model showed that neither aging nor obesity can explain the phenomenon.

“It points to this mysterious conclusion: A lot of cases of osteoarthritis, which we thought might be inevitable, may be preventable… and are due to unknown factors,” Wallace says.

Of course, both obesity and aging take their toll — no one’s saying they just don’t matter. But what this study shows is that there’s something else we’re missing.

What could it be?

The study didn’t attempt to explain the findings, but it’s not very difficult to speculate. Wallace too says that lack of physical activity is a very likely culprit. Since the 1950s, office jobs have multiplied dramatically, more and more cars flood the streets, and physical activity has declined accordingly. Sitting down is also a possible culprit. David Felson, study co-author, a renowned arthritis expert and physician at Boston University comments:

“Our joints don’t do well when they aren’t active much of the time,” Felson says.

But that might not tell the whole story. Inflammation might also be at blame. Arthritis itself is an inflammation, but different inflammations, while a natural reaction, promote injury and prevent proper healing. Francis Berenbaum, a researcher and physician at Pierre and Marie Curie University and  AP-HP hospital in Paris, France, who wasn’t involved in the study, believes an unhealthy diet might also be at blame. The same diet (high in processed foods and sugars) that’s favoring diabetes and heart diseases might also be contributing to arthritis. Other factors, such as walking more on hard surfaces such as concrete or asphalt or concrete might also contribute, but at the moment, the truth is we don’t really know.

“I study this, and I don’t know… what [more] can be done to prevent it,” Felson adds.

For now, your best bet is to keep a healthy diet and be physically active.

Journal Reference: Ian J. Wallace, Steven Worthington, David T. Felson, Robert D. Jurmain, Kimberly T. Wren, Heli Maijanen, Robert J. Woods, and Daniel E. Lieberman — Knee osteoarthritis has doubled in prevalence since the mid-20th century. doi: 10.1073/pnas.1703856114

Skeletal hand.

Early Europeans may have survived the Ice Age because of arthritis

For those days when arthritis, here’s something to keep in mind: at one point in human history, it may have been the thing that kept early Europeans alive.

Skeletal hand.

Image via Pixabay.

Roughly one-half of all Europeans living today carry a variant of the GDF5 gene which nearly doubles the chance of arthritis popping up in our golden years. People from other areas of the world have it too, but in much lower percentages of the population — so what gives?

Well, achy joints may have kept the early settlers of Europe survive frostbite and prevent fractures in the new, colder climate, researchers from the US report.

Little cavemen, short and stout

The same GDF5 variant which increases the likelihood of arthritis also seems to shave roughly 1 cm in the height of people who harbor it. So why on Earth would a gene that makes you shorter and ultimately less mobile not only persist but actually proliferate in a population?

Well, it’s all about context. While those traits above are arguably disadvantages when trying to secure a mate or going about your Stone Age day, they can also help a population recently moved out of Africa better adapt to the freezing northern territories of Europe. Being short and stocky makes it easier to retain heat in cold weather, and as the old saying informs us, the shorter you are the more lightly you fall — so you’re at less of a risk of fracturing bones in the process, a life-threatening experience back in those days.

As for the evolutionary costs, arthritis may actually carry less than you’d initially assume. As the condition usually develops past reproductive ages, it didn’t actually impair people’s ability to have babies. In other words, it brought more to the table than it took — so the gene got passed down.

“This gene variant is present in billions of people, and it’s likely responsible for millions of cases of arthritis around the globe” says Dr David Kingsley, Professor of developmental biology at Stanford University and paper co-author.

“Many people think of osteoarthritis as a kind of wear-and-tear disease, but there’s clearly a genetic component at work here as well. It’s possible that climbing around in cold environments was enough of a risk factor to select for a protective variant even if it brought along an increased likelihood of an age-related disease like arthritis, which typically doesn’t develop until late in life.”

The link between arthritis and GDF5 was first established back in the 1990s, and since then research has also linked its expression to a genetic mechanism called GROW1, which signals the gene to turn off bone growth.

The team analyzed the genomes of people from across the world who submitted their genetic material to the 1,000 Genomes project. They noticed that the genetic variant and the mechanism for switching off bone growth was far more common in populations from Europe or those of European descent. In much warmer places, such as Africa for example, the gene variant was extremely rare in the overall population.

The gene variant also seems to have been pretty common in Neanderthals and Denisovans, who inhabited Europe and Asia for about 600,000 years before modern humans came around and drove them extinct — in fact, it’s likely that Europeans today inherited the gene from these initial populations.

Of course, while it could have saved our ancestors during the Ice Age, arthritis may be overstaying its welcome today.

“The variant that decreases height is lowering the activity of GDF5 in the growth plates of the bone,” said Dr Terence Capellini, associate professor of human evolutionary biology at Harvard University and first author of the paper.

“Interestingly, the region that harbors this variant is closely linked to other mutations that affect GDF5 activity in the joints, increasing the risk of osteoarthritis in the knee and hip.”

The paper “Ancient selection for derived alleles at a GDF5 enhancer influencing human growth and osteoarthritis risk” has been published in the journal Nature Genetics.

Devil’s Claw brings new hope for arthritis

devilsclaw03webDeep in one of the warmest places on the planet, in the Kalahari desert, there lies the ‘Devil’s Claw’, a plant that may hold the key to effective treatment to arthritis, tendonitis and numerous related illnesses that affect millions and millions each year. Despite being a ‘desert plant’ the Devil’s Claw doesn’t thrive in extreme drough, like the one the Kalahari desert has seen in the past few years. This lead the plant to the brink of extinction so scientists are trying to find out ways to grow it, or grow other plants that produce the same valuable chemicals, or produce the chemicals in a lab.

Today was the 238th National Meeting of the American Chemical Society (ACS). At that meeting, they described the first successful method of producing the active ingredients in the plant, ingredients that have already made the Devil’s Claw sought after by more and more people who use it as alternative medicine – with amazing results. Researchers hope this will eventually lead to ‘biofactories’ that could produce huge quantities of the needed substances at low costs.

They started studying this plant when they found out that native populations from South Africa have been using it for generations in a number of conditions, from fever and diarrhea to serious blood diseases.

“In Germany, 57 pharmaceutical products based on Devil’s claw, marketed by 46 different companies, have cumulative sales volumes alone worth more than $40 million.”, said Milen I. Georgiev, Ph.D., who delivered the report

“The Devil’s Claw faces significant problems with its natural renewal, especially low rainfall,” Georgiev notes. “These problems are driving efforts to find alternative ways to produce high value compounds from the plant, independent of geographical and climatic factors,” he says.

Another extremely interesting fact (though not directly related) is that 25 percent of ALL medicines prescribed in industrialized countries comes from plants, most of which are endangered, so these biofactories that could ensure fast growth rate and genetic stability for the necessary plants could be crucial.

“Our target aim is to develop such technology, so we are paying attention not only to fundamental scientific tasks, but also to those related to some of the technological problems associated with hairy root biofactories,” Georgiev said. “It is the desire of each scientist is to see the fruits of his work. In the current case, we hope to be able to develop cost-effective laboratory technology for production of these pharmaceutically-important metabolites within the next five years.”