Regrowing Amputated Limbs Is Getting Closer to Medical Reality
In June 2012, Kirstie Ennis was six months into her second deployment to Afghanistan and recently promoted to sergeant. The helicopter gunner and seven others were three hours into a routine mission of combat resupplies and troop transport when their CH-53D helicopter went down hard.
Miraculously, all eight people onboard survived, but Ennis' injuries were many and severe. She had a torn rotator cuff, torn labrum, crushed cervical discs, facial fractures, deep lacerations and traumatic brain injury. Despite a severely fractured ankle, doctors managed to save her foot, for a while at least.
In November 2015, after three years of constant pain and too many surgeries to count, Ennis relented. She elected to undergo a lower leg amputation but only after she completed the 1,000-mile, 72-day Walking with the Wounded journey across the UK.
On Veteran's Day of that year, on the other side of the country, orthopedic surgeon Cato Laurencin announced a moonshot challenge he was setting out to achieve on behalf of wounded warriors like Ennis: the Hartford Engineering A Limb (HEAL) Project.
Laurencin, who is a University of Connecticut professor of chemical, materials and biomedical engineering, teamed up with experts in tissue bioengineering and regenerative medicine from Harvard, Columbia, UC Irvine and SASTRA University in India. Laurencin and his colleagues at the Connecticut Convergence Institute for Translation in Regenerative Engineering made a bold commitment to regenerate an entire limb within 15 years – by the year 2030.
Dr. Cato Laurencin pictured in his office at UConn.
Photo Credit: UConn
Regenerative Engineering -- A Whole New Field
Limb regeneration in humans has been a medical and scientific fascination for decades, with little to show for the effort. However, Laurencin believes that if we are to reach the next level of 21st century medical advances, this puzzle must be solved.
An estimated 185,000 people undergo upper or lower limb amputation every year. Despite the significant advances in electromechanical prosthetics, these individuals still lack the ability to perform complex functions such as sensation for tactile input, normal gait and movement feedback. As far as Laurencin is concerned, the only clinical answer that makes sense is to regenerate a whole functional limb.
Laurencin feels other regeneration efforts were hampered by their siloed research methods with chemists, surgeons, engineers all working separately. Success, he argues, requires a paradigm shift to a trans-disciplinary approach that brings together cutting-edge technologies from disparate fields such as biology, material sciences, physical, chemical and engineering sciences.
As the only surgeon ever inducted into the academies of Science, Medicine and Innovation, Laurencin is uniquely suited for the challenge. He is regarded as the founder of Regenerative Engineering, defined as the convergence of advanced materials sciences, stem cell sciences, physics, developmental biology and clinical translation for the regeneration of complex tissues and organ systems.
But none of this is achievable without early clinician participation across scientific fields to develop new technologies and a deeper understanding of how to harness the body's innate regenerative capabilities. "When I perform a surgical procedure or something is torn or needs to be repaired, I count on the body being involved in regenerating tissue," he says. "So, understanding how the body works to regenerate itself and harnessing that ability is an important factor for the regeneration process."
The Birth of the Vision
Laurencin's passion for regeneration began when he was a sports medicine fellow at Cornell University Medical Center in the early 1990s. There he saw a significant number of injuries to the anterior cruciate ligament (ACL), the major ligament that stabilizes the knee. He believed he could develop a better way to address those injuries using biomaterials to regenerate the ligament. He sketched out a preliminary drawing on a napkin one night over dinner. He has spent the next 30 years regenerating tissues, including the patented L-C ligament.
As chair of Orthopaedic Surgery at the University of Virginia during the peak of the wars in Iraq and Afghanistan, Laurencin treated military personnel who survived because of improved helmets, body armor and battlefield medicine but were left with more devastating injuries, including traumatic brain injuries and limb loss.
"I was so honored to care for them and I so admired their steadfast courage that I became determined to do something big for them," says Laurencin.
When he tells people about his plans to regrow a limb, he gets a lot of eye rolls, which he finds amusing but not discouraging. Growing bone cells was relatively new when he was first focused on regenerating bone in 1987 at MIT; in 2007 he was well on his way to regenerating ligaments at UVA when many still doubted that ligaments could even be reconstructed. He and his team have already regenerated torn rotator cuff tendons and ACL ligaments using a nano-textured fabric seeded with stem cells.
Even as a finalist for the $4 million NIH Pioneer Award for high-risk/high-reward research, he faced a skeptical scientific audience in 2014. "They said, 'Well what do you plan to do?' I said 'I plan to regenerate a whole limb in people.' There was a lot of incredulousness. They stared at me and asked a lot of questions. About three days later, I received probably the best score I've ever gotten on an NIH grant."
In the Thick of the Science
Humans are born with regenerative abilities--two-year-olds have regrown fingertips--but lose that ability with age. Salamanders are the only vertebrates that can regenerate lost body parts as adults; axolotl, the rare Mexican salamander, can grow extra limbs.
The axolotl is important as a model organism because it is a four-footed vertebrate with a similar body plan to humans. Mapping the axolotl genome in 2018 enhanced scientists' genetic understanding of their evolution, development, and regeneration. Being easy to breed in captivity allowed the HEAL team to closely study these amphibians and discover a new cell type they believe may shed light on how to mimic the process in humans.
"Whenever limb regeneration takes place in the salamander, there is a huge amount of something called heparan sulfate around that area," explains Laurencin. "We thought, 'What if this heparan sulfate is the key ingredient to allowing regeneration to take place?' We found these groups of cells that were interspersed in tissues during the time of regeneration that seemed to have connections to each other that expressed this heparan sulfate."
Called GRID (Groups that are Regenerative, Interspersed and Dendritic), these cells were also recently discovered in mice. While GRID cells don't regenerate as well in mice as in salamanders, finding them in mammals was significant.
"If they're found in mice. we might be able to find these in humans in some form," Laurencin says. "We think maybe it will help us figure out regeneration or we can create cells that mimic what grid cells do and create an artificial grid cell."
What Comes Next?
Laurencin and his team have individually engineered and made every single tissue in the lower limb, including bone, cartilage, ligament, skin, nerve, blood vessels. Regenerating joints and joint tissue is the next big mile marker, which Laurencin sees as essential to regenerating a limb that functions and performs in the way he envisions.
"Using stem cells and amnion tissue, we can regenerate joints that are damaged, and have severe arthritis," he says. "We're making progress on all fronts, and making discoveries we believe are going to be helping people along the way."
That focus and advancement is vital to Ennis. After laboring over the decision to have her leg amputated below the knee, she contracted MRSA two weeks post-surgery. In less than a month, she went from a below-the-knee-amputee to a through-the-knee amputee to an above-the-knee amputee.
"A below-the-knee amputation is night-and-day from above-the-knee," she said. "You have to relearn everything. You're basically a toddler."
Kirstie Ennis pictured in July 2020.
Photo Credit: Ennis' Instagram
The clock is ticking on the timeline Laurencin set for himself. Nine years might seem like forever if you're doing time but it might appear fleeting when you're trying to create something that's never been done before. But Laurencin isn't worried. He's convinced time is on his side.
"Every week, I receive an email or a call from someone, maybe a mother whose child has lost a finger or I'm in communication with a disabled American veteran who wants to know how the progress is going. That energizes me to continue to work hard to try to create these sorts of solutions because we're talking about people and their lives."
He devotes about 60 hours a week to the project and the roughly 100 students, faculty and staff who make up the HEAL team at the Convergence Institute seem acutely aware of what's at stake and appear equally dedicated.
"We're in the thick of the science in terms of making this happen," says Laurencin. "We've moved from making the impossible possible to making the possible a reality. That's what science is all about."
Friday Five: The Therapeutic Value of Bonding with Fellow Sports Fans
The Friday Five covers five stories in research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on new scientific theories and progress to give you a therapeutic dose of inspiration headed into the weekend.
This episode includes an interview with Dr. Helen Keyes, Head of the School of Psychology and Sports Science at Anglia Ruskin University.
Listen on Apple | Listen on Spotify | Listen on Stitcher | Listen on Amazon | Listen on Google
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Matt Fuchs is the editor-in-chief of Leaps.org and Making Sense of Science. He is also a contributing reporter to the Washington Post and has written for the New York Times, Time Magazine, WIRED and the Washington Post Magazine, among other outlets. Follow him @fuchswriter.
The rise of remote work is a win-win for people with disabilities and employers
Disability advocates see remote work as a silver lining of the pandemic, a win-win for adults with disabilities and the business world alike.
Any corporate leader would jump at the opportunity to increase their talent pool of potential employees by 15 percent, with all these new hires belonging to an underrepresented minority. That’s especially true given tight labor markets and CEO desires to increase headcount. Yet, too few leaders realize that people with disabilities are the largest minority group in this country, numbering 50 million.
Some executives may dread the extra investments in accommodating people’s disabilities. Yet, providing full-time remote work could suffice, according to a new study by the Economic Innovation Group think tank. The authors found that the employment rate for people with disabilities did not simply reach the pre-pandemic level by mid-2022, but far surpassed it, to the highest rate in over a decade. “Remote work and a strong labor market are helping [individuals with disabilities] find work,” said Adam Ozemik, who led the research and is chief economist at the Economic Innovation Group.
Disability advocates see this development as a silver lining of the pandemic, a win-win for adults with disabilities and the business world alike. For decades before the pandemic, employers had refused requests from workers with disabilities to work remotely, according to Thomas Foley, executive director of the National Disability Institute. During the pandemic, "we all realized that...many of us could work remotely,” Foley says. “[T]hat was disproportionately positive for people with disabilities."
Charles-Edouard Catherine, director of corporate and government relations for the National Organization on Disability, said that remote-work options had been advocated for many years to accommodate disabilities. “It’s a little frustrating that for decades corporate America was saying it’s too complicated, we’ll lose productivity, and now suddenly it’s like, sure, let’s do it.”
The pandemic opened doors for people with disabilities
Early in the pandemic, employment rates dropped for everyone, including people with disabilities, according to Ozemik’s research. However, these rates recovered quickly. In the second quarter of 2022, people with disabilities aged 25 to 54, the prime working age, are 3.5 percent more likely to be employed, compared to before the pandemic.
What about people without disabilites? They are still 1.1 percent less likely to be employed.
These numbers suggest that remote work has enabled a substantial number of people with disabilities to find and retain employment.
“We have a last-in, first-out labor market, and [people with disabilities] are often among the last in and the first out,” Olzemik says. However, this dynamic has changed, with adults with disabilities seeing employment rates recover much faster. Now, the question is whether the new trend will endure, Olzemik adds. “And my conclusion is that not only is it a permanent thing, but it’s going to improve.”
Gene Boes, president and chief executive of the Northwest Center, a Seattle organization that helps people with disabilities become more independent, confirms this finding. “The new world we live in has opened the door a little bit more…because there’s just more demand for labor.”
Long COVID disabilities put a premium on remote work
Remote work can help mitigate the impact of long COVID. The U.S. Centers for Disease Control and Prevention reports that about 19 percent of those who had COVID developed long COVID. Recent Census Bureau data indicates that 16 million working age Americans suffer from it, with economic costs estimated at $3.7 trillion.
Certainly, many of these so-called long-haulers experience relatively mild symptoms - such as loss of smell - which, while troublesome, are not disabling. But other symptoms are serious enough to be disabilities.
According to a recent study from the Federal Reserve Bank of Minneapolis, about a quarter of those with long COVID changed their employment status or working hours. That means long COVID was serious enough to interfere with work for 4 million people. For many, the issue was serious enough to qualify them as disabled.
Indeed, the Federal Reserve Bank of New York found in a just-released study that the number of individuals with disabilities in the U.S. grew by 1.7 million. That growth stemmed mainly from long COVID conditions such as fatigue and brain fog, meaning difficulties with concentration or memory, with 1.3 million people reporting an increase in brain fog since mid-2020.
Many had to drop out of the labor force due to long COVID. Yet, about 900,000 people who are newly disabled have managed to continue working. Without remote work, they might have lost these jobs.
For example, a software engineer at one of my client companies has struggled with brain fog related to long COVID. With remote work, this employee can work during the hours when she feels most mentally alert and focused, even if that means short bursts of productivity throughout the day. With flexible scheduling, she can take rests, meditate, or engage in activities that help her regain focus and energy. Without the need to commute to the office, she can save energy and time and reduce stress, which is crucial when dealing with brain fog.
In fact, the author of the Federal Reserve Bank of New York study notes that long COVID can be considered a disability under the Americans with Disability Act, depending on the specifics of the condition. That means the law can require private employers with fifteen or more staff, as well as government agencies, to make reasonable accommodations for those with long COVID. Richard Deitz, the author of this study, writes in the paper that “telework and flexible scheduling are two accommodations that can be particularly beneficial for workers dealing with fatigue and brain fog.”
The current drive to return to the office, led by many C-suite executives, may need to be reconsidered in light of legal and HR considerations. Arlene S. Kanter, director of the disability law and policy program at the Syracuse University College of Law, said that the question should depend on whether people with disabilities can perform their work well at home, as they did during Covid outbreaks. “[T]hen people with disabilities, as a matter of accommodation, shouldn’t be denied that right,” Kanter said.
But companies shouldn’t need to worry about legal regulations. It simply makes dollars and sense to expand their talent pool by 15% of an underrepresented minority. After all, extensive research shows that improving diversity boosts both decision-making and financial performance.
Companies that are offering more flexible work options have already gained significant benefits in terms of diverse hires. In its efforts to adapt to the post-pandemic environment, Meta, the owner of Facebook and Instagram, decided to offer permanent fully remote work options to its entire workforce. And according to Meta chief diversity officer Maxine Williams, the candidates who accepted job offers for remote positions were “substantially more likely” to come from diverse communities: people with disabilities, Black, Hispanic, Alaskan Native, Native American, veterans, and women. The numbers bear out these claims: people with disabilities increased from 4.7 to 6.2 percent of Meta’s employees.
Having consulted for 21 companies to help them transition to hybrid work arrangements, I can confirm that Meta’s numbers aren’t a fluke. The more my clients proved willing to offer remote work, the more staff with disabilities they recruited - and retained. That includes employees with mobility challenges. But it also includes employees with less visible disabilities, such as people with long COVID and immunocompromised people who feel reluctant to put themselves at risk of getting COVID by coming into the office.
Unfortunately, many leaders fail to see the benefits of remote work for underrepresented groups, such as those with disabilities. Some even say the opposite is true, with JP Morgan CEO Jamie Dimon claiming that returning to the office will aid diversity.
What explains this poor executive decision making? Part of the answer comes from a mental blindspot called the in-group bias. Our minds tend to favor and pay attention to the concerns of those in the group of people who seem to look and think like us. Dimon and other executives without disabilities don’t perceive people with disabilities to be part of their in-group. They thus are blind to the concerns of those with disabilities, which leads to misperceptions such as Dimon’s that returning to the office will aid diversity.
In-group bias is one of many dangerous judgment errors known as cognitive biases. They impact decision making in all life areas, ranging from the future of work to relationships.
Another relevant cognitive bias is the empathy gap. This term refers to our difficulty empathizing with those outside of our in-group. The lack of empathy combines with the blindness from the in-group bias, causing executives to ignore the feelings of employees with disabilities and prospective hires.
Omission bias also plays a role. This dangerous judgment error causes us to perceive failure to act as less problematic than acting. Consequently, executives perceive a failure to support the needs of those with disabilities as a minor matter.
The failure to empower people with disabilities through remote work options will prove costly to the bottom lines of companies. Not only are limiting their talent pool by 15 percent, they’re harming their ability to recruit and retain diverse candidates. And as their lawyers and HR departments will tell them, by violating the ADA, they are putting themselves in legal jeopardy.
By contrast, companies like Meta - and my clients - that offer remote work opportunities are seizing a competitive advantage by recruiting these underrepresented candidates. They’re lowering costs of labor while increasing diversity. The future belongs to the savvy companies that offer the flexibility that people with disabilities need.