Tag: Knee

Elon Musk Bends the Knee to Donald Trump

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Have you ever watched a crowd go wild for a PowerPoint slide? After a few introductory hellos yesterday in Butler, Pennsylvania, Donald Trump gestured to a screen showing the same graph on illegal immigration that he had been talking about when he was nearly assassinated in July and delivered his real opening line: “As I was saying …”

The audience loved that. The rallygoers had waited in line for hours in the hot sun to get into the field, and this was their reward. They had made it through warm-up speeches by J. D. Vance, Lara Trump, and Scott Presler, the last of these being the founder of Gays for Trump and the March Against Sharia, who promised any Amish people watching that Trump would “protect your raw milk … protect your ability to afford to have 10 beautiful children per family.” (One of the wonders of the MAGA movement is how it absorbs other political positions—in this case, crunchiness and pro-natalism—into one seamless mythology.) After that came the crowd’s moment to rejoice in the defeat of, as Trump put it, “a cold-blooded assassin [who] aimed to silence me and silence the greatest movement, MAGA, in the history of our country.” An opera singer even performed “Ave Maria.”

Famously, the Gettysburg address was just 271 words long. Trump’s speech went on for 90 minutes. The contrast between the bits of the speech he read from the teleprompters, which covered “hallowed places” and monuments to valor, and the ad-libbed sections, which featured digressions about potholes and the Olympic boxing controversy, was stark. How can we say that America has an attention-span “crisis” when people are volunteering to listen to this stuff?

Charlie Warzel: Elon Musk has reached a new low

The real highlight of the show, however, was when the former president brought Elon Musk onstage. The billionaire had been posting excitedly all day about his endorsement of the former president—yes, a man who prides himself, Cartman-like, on refusing to cede to any outside authority was positively giddy about the chance to publicly swear fealty to Trump.

Musk used to claim that he was a disappointed Democrat, and that he wanted X to reflect the breadth of American opinion. “For Twitter to deserve public trust, it must be politically neutral,” he posted in April 2022, as he was in the middle of buying it. Three months later, he argued that Trump was too old to run for president again: “It’s time for Trump to hang up his hat & sail into the sunset.”

The former president took that about as well as you would expect. “When Elon Musk came to the White House asking me for help on all of his many subsidized projects, whether it’s electric cars that don’t drive long enough, driverless cars that crash, or rocketships to nowhere, without which subsidies he’d be worthless, and telling me how he was a big Trump fan and Republican, I could have said, ‘drop to your knees and beg,’ and he would have done it,” he posted on Truth Social in July 2022.

Musk did not drop to his knees and beg in Butler, but he didn’t have to—he has already made his MAGA loyalism very clear on X. Yesterday he capered behind Trump. Honestly, credit to his 53-year-old knees for being so limber. He gamboled. He frolicked, frisky as a spring lamb, fertile as a spawning salmon, executing a series of small jumps behind the ex-president and exposing a few inches of pallid stomach as his OCCUPY MARS T-shirt rode up. “He saved free speech,” said Trump, who nonetheless looked slightly alarmed at Musk’s exuberance. “He created so many different great things.”

Musk took the mic and gestured to his MAGA hat—black on black instead of the usual white on red. “As you can see,” he told the crowd, “I’m not just MAGA. I’m dark MAGA.”

Earlier in the proceedings, Vance had painted Trump as the victim of inflammatory rhetoric rather than one of its main proponents. Musk now tried a similar Uno reverse card, arguing that Trump was the only candidate who could be trusted “to preserve the Constitution, to preserve democracy in America.” He showed no awareness that Trump, as the latest court filings suggest, tried to intimidate his vice president out of certifying the 2020 election results and then reacted with callous indifference when a mob threatened Mike Pence’s life as a result. (“So what?” Trump is alleged to have said.) In between repeatedly apologizing for repeating himself, Musk also managed to say that if Trump did not win, “this’ll be the last election. That’s my prediction.”

Tyler Austin Harper: A legendary American photograph

After Musk took his seat again, Trump lavished more praise on the billionaire. He had no idea what the satellite network Starlink was, he said, but he had heard from those affected by Hurricane Helene that they wanted it, and he had called Musk. Just like that—while the two men were still on the phone—Starlink was on its way to North Carolina and Georgia. This was the purest essence of strongman politics, implying that anything can be solved by the right guy talking to the right other guy. No holdups, no bureaucracy, no need even for the leader to understand what’s going on. Just simple problems and simple solutions.

At this, the crowd started to chant: “Elon! Elon! Elon!”

This was probably the reception that Musk had hoped for when he bought Twitter. He didn’t find it then, of course: Many of his best engineers have quit, foreign judges have ruled against him, advertisers have deserted him, and prominent people have left the platform. No matter. In Butler, Pennsylvania, was the adoration Musk seems to crave. He must believe that Trump will let him do whatever he wants—including, as the ex-president put it, “reach Mars before the end of my term.” And why not? That wasn’t the most ludicrous thing uttered onstage in Butler.

The pact between Musk and Trump gives both men something they want—a megaphone for their ideas, a conduit to their fans, an ability to shape the political conversation. Yesterday was supposed to be a celebration of the former president’s miraculous survival and a tribute to the brave Americans who risked their lives to help others in the shooting. Instead it marked an unpredictable alliance between the world’s richest man and the politician who has successfully bullied and flattered him into bending the knee.

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October 6, 2024
A dash of gallium may make for stabler hip and knee implants

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While titanium hip and knee implants do restore mobility to a great many people, they’re still subject to failure. A new alloy could help change that, simply by adding a smidge of bendy, bacteria-killing gallium to the mix.

Regardless of whether the implant replaces a hip or a knee, there’s a distinct boundary where the titanium device meets the patient’s natural bone tissue. If bacteria colonize the surface of the implant at that interface, an infection may occur that will ultimately cause the bone/implant connection to fail. Once that has happened, a second surgery will be required.

Another potential problem comes from the fact that the type of titanium most often used for implants, Ti-6Al-4V, is stiffer than bone. This means that the implant doesn’t flex as much as the bone to which it’s attached, concentrating stress at the interface between the two. Not only may this cause the connection to fail over time, it can also be a source of pain to the patient.

In an effort to address both of these problems, scientists from Australia’s Flinders University recently added gallium (Ga) to Ti-6Al-4V. Not only is the metal known to possess antibacterial qualities, it’s also more flexible than titanium (Ti).

The researchers only added a little bit of gallium, however. One of the Ti/Ga alloys they created just 3% gallium by weight, while the other was only 5%. For the purposes of the study, the samples took the form of rods, not implants.

When exposed to Pseudomonas aeruginosa bacteria (which frequently infects implants) the two new alloys were found to eradicate 90% (+/- 5%) and 95% (+/-3%) of the microbes respectively, over a six-hour period. By contrast, a control sample of Ti-6Al-4V titanium killed only 3% (+/-2%).

Importantly, the antibacterial effect of the two Ti/Ga alloys continued after the initial six-hour “killing spree,” and no harmful effects to human cells were observed over a 24-hour period.

What’s more, when the alloys were strength-tested, the 3% Ga version exhibited a Young’s modulus that was 37% less than that of Ti-6Al-4V, while the 5% Ga version was 44% less. The Young’s modulus is a measurement of how easy it is to bend a material.

That said, the two new alloys aren’t weak. Their hardness, which is their ability to withstand surface deformation, falls just short of that of Ti-6Al-4V. Additional research could boost their hardness further.

“The alloys in this work have shown very promising results and are part of ongoing efforts to improve components in orthopedic implants,” says Dr. Reza Hashemi, who led the study along with Materials Engineering graduate Rhianna McHendrie. “Compared to existing prostheses, the addition of gallium produces a superior material with antibacterial properties to improve patient outcomes while reducing potential pain, medical complications and long-term implant failure.”

A paper on the study was recently published in the Journal of Functional Biomaterials.

Source: Flinders University

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August 14, 2024
Knee ‘plug’ simplifies surgery and recovery

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An osteochondral defect (OCD) is an area of focal damage involving the articular cartilage that lines the joint’s bony surface and a piece of underlying bone. OCDs in the knee can result from arthritis or an acute traumatic injury – a football tackle, for example – that causes arthritis, leading to chronic pain and loss of joint function.

Knee OCDs can be treated conservatively with joint immobilization and pain medications, but if the condition is advanced or severe, surgery is required, including total knee replacement. Now, researchers at Texas A&M University have received a grant from the National Institute of Arthritis and Musculoskeletal and Skin Disease, part of the National Institutes of Health (NIH), to develop their cartilage-capped regenerative osteochondral plugs (CC-ROPs), an off-the-shelf synthetic device that could be an alternative to total knee replacement.

“Chronic knee pain and disability are caused by cartilage loss and OCDs stemming from arthritis, including osteoarthritis and post-traumatic arthritis, causing individuals pain that limits comfort and mobility,” said Melissa Grunlan, a professor in the University’s Department of Biomedical Engineering. “This grant will allow us to maximize the potential of the CC-ROPs to heal OCDs and to collect data demonstrating this efficacy.”

Autografting is commonly the step before total knee replacement surgery. It involves harvesting cylindrical ‘plugs’ from non-damaged sections of the patient’s knee and implanting them in a hole or holes drilled in the affected area. Over time, the implants enable bone and cartilage to grow into the damaged area. However, the procedure’s effectiveness is limited when the patient is older than 40, or the OCD is large. Where autografting is deemed inappropriate, a total knee replacement is sometimes the patient’s only option.

Mock-up of a total knee replacement showing the metal components and plastic spacer

Total knee replacement is extensive surgery, although the name is kind of a misnomer. Only the surfaces of the bones are replaced. The surgeon removes the damaged cartilage and a small amount of underlying bone and replaces it with metal components to recreate the joint surface. A plastic spacer is placed between the metal components to provide a smooth, gliding surface. About 790,000 total knee replacements are done in the US each year.

CC-ROPs comprise an ultra-strong hydrogel cap that mimics the properties of natural cartilage and a porous polymer scaffold base. Because they’re similar to the cylindrical plugs used in autografts, the same protocols and tools can be used. Like autografts, following implantation into a pre-drilled hole, the porous base of the CC-ROP enables the growth of new bone tissue, while the cap provides the ‘cartilage’ needed for joint function. However, unlike autografting, CC-ROPs are not limited by patient age or defect size. And they don’t require pre-loading with cells or growth factors to accelerate healing.

Having now secured funding, the researchers at Texas A&M University can work on maximizing the functionality of CC-ROPs to ensure they’re ready for real-life applications. Planned pre-clinical studies will evaluate the device’s effectiveness.

Source: Texas A&M University

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June 3, 2024
The Best Stretches for the Back of the Knee to Reduce Pain
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The best stretches for the back of the knee focus on the hamstrings and calves, both of which cross the back of the joint.

Image Credit:
MangoStar_Studio/iStock/GettyImages

In This Article

Your knees are important joints — think about how much they do in essentially every single lower-body movement you do, like standing up out of a chair, walking, cycling and squatting in the gym. Tightness or pain in the back of the knee can limit your ability to do all of those things (and more) comfortably.

There are a handful of things that can contribute to back-of-knee tightness (scroll down for the list). And, fortunately, there are also several stretches for the back of the knee that can help relieve tightness — no matter which muscle or tendon is causing it, says Sarah Gallagher, PT, DPT, a physical therapist and owner of South Valley Physical Therapy in Denver.

Try These 6 Stretches for the Back of the Knee

Looking to loosen the muscles behind your knee? Add these knee flexibility exercises into your routine. Try to stretch the area at least once every day. You can do these multiple times a day, though, if you feel like you need it.

Gallagher recommends doing these knee stretches when your muscles are already warm, like after your regular workout or any other physical activity like walking around your house. You can also do them at other times when you feel like you just need a good stretch, but it might just take a little longer for them to loosen up.

For optimal results, she suggests holding each stretch for 1 minute, repeating each stretch 3 times.
1. Seated Figure-4 Hamstrings Stretch

Image Credit: Sarah Gallagher/LIVESTRONG.com

Sit on the ground with one leg extended in front of you and the other bent into a figure four with the foot resting against your inner thigh.

Hinge forward with a straight back over the straight leg.

Hold, then repeat on the other leg.
The figure-4 stretch is a great way to address hamstring tightness behind the knee.

“Stretching each leg separately addresses each one at its level of tightness,” Gallagher says. Chances are, one might be tighter than the other, and if you stretch both legs at once you’ll only sufficiently stretch the tighter one.
2. Chair Hamstrings Stretch

Image Credit: Sarah Gallagher/LIVESTRONG.com

Sit tall on the edge of a chair and extend one leg out in front of you. Bend your other knee and place your foot flat on the floor.

Hinge forward with a straight back over your straight leg.

Hold, then repeat on the other leg.
Gallagher suggests this gentle knee stretch to people who spend a long time sitting at a desk because it lets you loosen the hamstring muscles behind the knee without requiring you to even get up. “You can do this desk stretch while you’re working and get a great benefit,” she says.
3. Heel Hang

Image Credit: Sarah Gallagher/LIVESTRONG.com

Stand in a staggered stance with the toes of your back foot on the edge of a curb or step.

Lightly bend your front knee and keep your back leg straight as you press back into your back leg so that your heel hangs off the curb or step.

Hold, then repeat on the other leg.
This stretch will help loosen up the gastrocnemius, and also makes for a good soleus muscle stretch.
4. Standing Calf Stretch With Straight Knee

Image Credit: Sarah Gallagher/LIVESTRONG.com

Stand facing a wall with staggered feet. Place your palms on the wall at shoulder height.

Bend your front knee and slowly lean toward the wall while keeping the heel of your back leg on the floor.

Hold, then repeat on the other leg.
By keeping your knee straight in this stretch, you focus on the gastrocnemius, which crosses behind the knee.
5. Standing Calf Stretch With Bent Knee

Image Credit: Sarah Gallagher/LIVESTRONG.com

Stand facing a wall with staggered feet. Place your palms on the wall at shoulder height.

Bend your front knee and slowly lean toward the wall while keeping the heel of your back leg on the floor.

Bend your back knee a bit to change the focus of the stretch to the soleus muscle.

Hold, then repeat on the other leg.
By bending your knee, you turn this move into a fantastic soleus stretch, Gallagher says. Your soleus is a calf muscle that connects close to the knee but doesn’t actually cross the joint.

Play around with this stretch. You can even alternate back and forth between a straight and bent knee.
6. Standing Hamstrings Stretch

Image Credit: Sarah Gallagher/LIVESTRONG.com

Stand in a staggered stance with the heel of your front foot on the edge of a curb or step.

Keeping both legs straight, press into your front heel and hinge forward over your leg until you feel a deep stretch down your hamstrings.

Hold, then repeat on the other leg.
This is similar to the chair hamstrings stretch. But because you do it from a standing position, you can get a wider range of motion and a deeper stretch.

3 Reasons Why the Muscles Behind Your Knee Are Tight

When people describe tightness behind the knee, it’s likely the result of a tight muscle, Gallagher says.

If you’re looking to blame a specific muscle for your tight knees, there are two likely culprits: the hamstring muscles and the calf muscles.

The hamstring muscles — the semitendinosus, semimembranosus and biceps femoris — are behind the knee and play a key role in hip extension (straightening) and knee flexion (bending), according to ‌StatPearls‌. They also help stabilize the knee.

While both of the calf muscles, the soleus and gastrocnemius, can contribute to knee tightness, the gastrocnemius crosses behind the knee and is the most likely of the calf muscles to cause tightness in the back of the knee. The gastroc is in charge of flexing and stabilizing the knee. Both the gastroc and soleus are involved in plantar flexion — aka, pointing your toes.

If you have a tight hamstring behind your knee or a tight calf muscle, chances are, you’ll feel some discomfort in the back of the knee. There are also tendons and other soft tissues behind the knee, like the posterior cruciate ligament, which can tighten up as well.

A lot of things can cause these muscles and tendons in the back of the knee to feel tight, resulting in that sensation of tightness behind the knee: your activity level, the type of exercises you do and even how you sit throughout the day can contribute.

1. Your Workouts Involve a Lot of Knee Flexion

“People who do exercises like running and cycling will probably be more prone to knee tightness because there is a lot of bending the knee in those activities, whereas someone who does yoga will not be as prone because this type of exercise inherently involves a lot of straightening of the knee,” Gallagher says.

2. You Sit a Lot With Bent Knees

It only makes matters worse when you do those sort of bent-knee exercises and then proceed to plop yourself in a chair for the rest of the day.

“People will get their exercise in and then go sit for eight hours and then stand up and feel like they can’t straighten their leg,” Gallagher says.

To prevent this back-of-knee tightness, she often recommends simply straightening your legs one at a time every 20 minutes or so. “People tend to bend or cross their legs but don’t straighten the knees.”

3. You Have Hunched Posture

Posture also plays a role here. “If you slump down in your chair, that shortens the hamstrings, too,” Gallgher says. If you sit that way every now and then, it shouldn’t cause any issues. But over time, it can really build up. “When you spend a third of your time like this, that’s when it can become trouble.”

The Effects of Back-of-Knee Tightness

Over time, if you have chronically short hamstrings or calves, you could develop other issues, like tendonitis in the hamstring or achilles or lower back pain, she says.

“When the hamstrings are tight, it puts a lot more strain on the lower back muscles.” Tightness in the back of the knee, and any lack of mobility, can also change how you move when you walk, run and cycle, which can make you more prone to injury, she adds.

The Benefits of Back-of-the-Knee Stretches

Stretching (as well as knee-strengthening exercises) can help counteract those possible effects of tightness. The stretches above loosen your hamstrings and calves, which minimizes strain on your lower back, promotes healthy movement patterns and wards off tendonitis and pain.

Tightness in the back of the knee can also be kind of painful. Doing these stretches for knee tightness might help relieve that pain, too, if it’s minor and actually due to the tightness.

But if your knee pain is ever sharp, or if it gets worse over time, stop what you’re doing. These are signs you might have an actual injury, and that needs to be addressed by a doctor or physical therapist.
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May 3, 2024
Leg Press Knee Pain: Causes and Solutions
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Knee pain from leg presses may be due to mistakes with your form or an underlying injury.

Image Credit:
bojanstory/E+/GettyImages

In This Article

While the leg press machine is a top pick for many gym-goers looking to build strong quads and glutes, it’s not uncommon to experience leg press knee pain, especially if you have an injury, use too much weight or have improper form.

Pain, while exercising or immediately following, is cause for concern. Finding out why you’re experiencing discomfort can help you prevent and treat any potential injuries.

Here are some common concerns that could be causing your pain and tips for protecting your knees when you use the leg press.

1. You Could Have Cartilage Damage

“During the phase of the leg press that involves deep knee flexion, the stress goes to the posterior aspect of the knee, or back of the knee, and the bones and cartilage in the back of the knee,” orthopedic surgeon and sports medicine specialist David Geier, MD, tells LIVESTRONG.com.

Often, that area is where cartilage damage and other structural damage like meniscus tears are found, Dr. Geier says. “Applying a large amount of stress to that part of the knee can cause pain in someone with early arthritis or other injuries.”

Knee injuries can involve any of the tendons, ligaments or bursae surrounding your knee joint, as well as the bones, cartilage and ligaments that form the joint, according to the Mayo Clinic.

Fix It

If you’re experiencing nagging knee pain that won’t go away — during or after you leg press — talk to your doctor, especially if you can’t bear weight on your knee, you’re experiencing swelling in and around the knee or you can’t fully extend or flex your knee, according to the Mayo Clinic.

2. Your Form Could Use Some Work

If you feel knee discomfort on the leg press machine, you might be doing it with improper form. Leg press form mistakes put unnecessary strain on your knees, which may cause pain or injury, according to the American Council on Exercise (ACE).
Fix It

Check your form in the mirror or ask a workout buddy to observe your movements. Here’s a refresher, according to the ACE:

Start sitting with your back flat against the machine’s backrest.

Place your feet flat on the resistance plate about shoulder-width apart with your knees at about 90-degree angles.

Hold the handles and engage your core.

Exhale and press through your feet to push the plate away from you until your legs are straight, but don’t lock your knees.

Pause here for a second, then slowly bend your knees to return to the starting position.
3. You’re Using Too Much Weight

Another way to leg press without knee pain is to make sure you’re using an appropriate amount of weight. Beginners should typically start with about 50 to 75 percent of their body weight. Heavier weight might put undue strain on your muscles and joints that could be painful.

Fix It

Start with lighter weight and perform more reps until you see how this exercise feels for you and your knees, Dr. Geier says. “If you do have knee pain from a prior injury or just wear and tear from years of being active, consider not going as deep with the exercise,” he adds.

Common Questions

Is the leg press safer for knees than squats?

“Generally speaking, the leg press is safer than many other knee exercises, especially leg extensions,” Dr. Geier says. That’s because the leg press is a closed-chain exercise, which means your feet stay planted on the plate of the machine the entire time.

Squats also require you keep your feet planted on a fixed surface (the floor). “This allows for both your quads and hamstrings to contract, protecting the knee during the motion,” Dr. Geier says.

Both exercises are safe for knees, but squats will work your glutes and hamstrings more than a seated leg press.

Should you wrap your knees to do leg presses?

You don’t have to, but if you’re lifting heavy, knee sleeves or wraps can help protect the knee joint and may limit pain or discomfort, according to the National Academy of Sports Medicine.

What exercises can you do instead of leg presses?

In addition to the squat, you can also try other leg press alternatives like lunges, deadlifts, rear-foot elevated split squats and wall sits. Cardio machines like stationary bikes and ellipticals are also gentle on sore knees.
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February 2, 2024