We are searching data for your request:
Upon completion, a link will appear to access the found materials.
Postal Abbreviation: DE
Population. 2010: 967,171
Legal Driving Age: 18
(16 w/ Driver's Ed.)
Age of Majority: 18
Median Age: 36
State Song: “Our Delaware”
Lyrics: George: B. Hynson
Music: Will M.S. Brown
Median Household Income:$63,068
Entered Union..... Dec. 7, 1787 (1st)
Present Constitution Adopted: 1897
Nickname: First State
“Liberty and Independence”
Origin of Name:
Named after Sir Thomas West, Lord De La Warr, first colonial governor of Virginia.
AGRICULTURE: chickens, corn,
eggs, fruit, soybeans, vegetables.
MINING: magnesium compounds,
sand and gravel.
electronics, instruments, paper
Total Area: 2,489 sq. miles
Land area: 1,955 sq. miles
Water Area: 535 sq. miles
Geographic Center: Kent County
11 mi. S of Dover
Highest Point: Ebright Road
New Castle County (442 ft.)
Lowest Point: Atlantic Ocean
Highest Recorded Temp.: 110˚ F (7/21/1930)
Lowest Recorded Temp.: -17˚ F (1/17/1893)
With the exception of the Northwest corner of the state (which is hilly), Delaware is extremely flat with fertile land very suitable for farming. The Atlantic coast of the state has dune covered beaches.
New Castle, 5,285
1638 Peter Minuit established the first permanent white settlement in Delaware
called New Sweden.
1655 Peter Stuyvesant captures New Sweden claiming it for Holland.
1735 Quakers settle in Delaware.
1777 The Battle of Brandywine is fought and lost by the General Washington
1787 Delaware became the first state to ratify the Constitution.
1800 The Duponts migrate from France to Delaware and establish a gunpowder
1861-65 During the Civil War Delaware does not secede from the Union.
1951 Delaware Memorial Bridge opens.
2000- Ruth Ann Miner becomes the first woman governor of the state
E.I. du Pont
Delaware National Sites
1) Fort Christina
Fort Christina (later renamed Fort Altena; Swedish: Fort Kristina) was the first Swedish settlement in North America and the principal settlement of the New Sweden colony. Built in 1638 and named after Queen Christina of Sweden, it was located approximately 1 mi (1.6 km) east of the present downtown Wilmington, Delaware, at the confluence of the Brandywine Creek and the Christina River, approximately 2 mi (3 km) upstream from the mouth of the Christina on the Delaware River..
2) Holy Trinity Church
The church was built in 1698–99 in the Swedish colony of New Sweden from local blue granite and Swedish bricks that had been used as ship's ballast. The church was situated on the site of the Fort Christina's burial ground, which dates to 1638. It is claimed that it is "the nation's oldest church building still standing as originally built". There are reportedly over 15,000 burials in the churchyard. Lutheran Church services were held in the Swedish language well into the 18th century.
3) New Castle Historic District
New Castle was originally settled by the Dutch West India Company in 1651, under the leadership of Peter Stuyvesant, on the site of a former aboriginal village, "Tomakonck" ("Place of the Beaver"), to assert their claim to the area based on a prior agreement with the aboriginal inhabitants of the area. The Dutch originally named the settlement Fort Casimir, but this was changed to Fort Trinity (Swedish: Trefaldighet) following its seizure by the colony of New Sweden on Trinity Sunday, 1654
Everything you wanted to know about '3-parent' babies
Who are the boy’s three “parents”?
The boy’s mother and father are a Jordanian couple who have already lost two children to a genetic disease called Leigh syndrome. The mother carries genes for this disease in her mitochondrial DNA, which is found in the cell’s energy-generating mitochondria. While we inherit the bulk of our DNA from both parents, mitochondrial DNA is only passed down from our mothers. To avoid passing on the disease-causing mitochondrial DNA, John Zhang and his colleagues at the New Hope Fertility Center in New York City used mitochondria from an egg belonging to another woman – an anonymous donor.
How much DNA comes from each person?
Almost all of the boy’s DNA will come from his mother and father. That’s because most of our genes – around 20,000 in total – are found in the cell’s nucleus just 37 are found in the mitochondria. In the new procedure, Zhang’s team removed the nucleus from one of the mother’s eggs and inserted it into a donor egg, which had its own nucleus removed. This egg was then fertilised with the father’s sperm. The resulting embryo therefore had nuclear DNA from its parents and mitochondrial DNA from the donor.
What do these 37 mitochondrial genes do?
These mainly code for enzymes that keep the mitochondria themselves functioning. While a malfunction can trigger a devastating disease, the genes are unlikely to code for the more obvious traits people inherit from their parents.
But because they power cells, mitochondria could indirectly affect other things by altering the way cells function. A few studies have suggested that mitochondrial DNA might influence a person’s athletic ability, how long they will live and even their IQ. The exact mechanisms aren’t clear.
Haven’t “three parent” babies been born before?
Yes, although using a different technique. Back in the 1990s, Jacques Cohen and his colleagues at the Institute for Reproductive Medicine and Science at Saint Barnabas in New Jersey were the first to inject fluid from healthy eggs – including their mitochondria – into eggs from women who had been through several rounds of failed IVF. The hope was that the donated mitochondria would boost the flagging eggs.
The team tried their technique 30 times in 27 people, and 17 babies were born. But two fetuses developed a genetic disorder, in which they lacked an X chromosome. One of these pregnancies resulted in a miscarriage, the other was aborted. This led to safety concerns. In 2001, the US Food and Drug Administration wrote to fertility clinics in the US, asking them to stop using the method, and to instead apply for approval from the FDA itself in all cases. The method, called ooplasmic transfer, fell out of favour at that point.
Is the new method safe?
As far as safety is concerned, it is too soon to know. The baby boy is the first to be born with the new method, so we have too few births to draw conclusions from. For now, though, it seems that the boy – now 5 months old – is healthy.
The primary concerns are that some faulty mitochondria could have slipped through the net. It is virtually impossible to leave behind all the mitochondria from the mother’s egg when removing the nucleus, even with the steadiest hand. And the level of mutated mitochondria that can cause symptoms varies by disease. One concern is that “bad” mitochondria, even in tiny amounts, could be better at replicating than “good” mitochondria – eventually tipping the balance and causing disease further down the line.
A second concern is that having mitochondria from two sources could disturb the normal relationship between the nucleus and mitochondria, although it is unclear if this is the case. It is a good sign that the boy is healthy, but he will need to be carefully monitored over the coming years.
Is the procedure legal?
It depends on where you want to do it. A similar technique was approved in the UK last year, although, as far as we know, no one in the country has tried it yet. Embryologists who want to carry out the procedure in the UK first have to apply for a licence, and then must follow a legal and ethical framework. They must also closely follow the development of any babies that are born.
In the US, it is up to the FDA to approve the procedure before it can be legally carried out. The country’s Institute of Medicine recommended that they do this back in February, at least for sons, who won’t be able to pass on any of the mitochondrial DNA they receive from the donor. The FDA has yet to make a decision. Zhang says that he tried to apply for FDA approval, but that the organisation told him there was no department set up that could review his application. So he performed the treatment in Mexico, where, as he puts it “there are no rules”. He hopes to continue his work in Mexico, China and the UK.
Why is it so controversial?
Some people don’t like the idea of a baby having three biological parents, and argue that mitochondrial DNA goes some way to shaping important characteristics, such as personality. But the scientific consensus is that swapping mitochondria is similar to changing a battery – it’s unlikely to have much, if any, influence over a person’s behaviour.
Others have argued that the technique is unnecessary. After all, it won’t help those who have already been born with mitochondrial diseases. Parents often don’t find out they are carriers of these diseases until they give birth to sick children. And those who do know they could pass on a disease have other options, such as using a donor egg. The technique is specifically for people who carry genes for the disease, but want to have a child genetically related to them.
Another concern is that, by creating a new mix of genetic material, embryologists are creating lasting genetic changes that will be passed down through generations, before we have a chance to find out if they are dangerous. Some argue that this starts us on a slippery slope of germ-line editing – one that could eventually lead to “designer babies”.
Could it have other uses?
Potentially. Some embryologists believe that ineffective mitochondria could be the cause of age-related infertility, and that eggs of older women fail to form viable embryos because they essentially lack energy. That’s the idea behind Augment – a treatment that uses mitochondria from a woman’s own ovarian stem cells to rejuvenate her egg cells. The team behind this project announced their first birth last year. However, many in the field remain sceptical – doubting that ovarian stem cells actually exist.
If ovarian stem cells don’t exist, but the theory behind the rejuvenation idea stacks up, then mitochondria taken from the eggs of young women could be used as an alternative.
Unlike other people finders, CheckPeople tries to keep things as simple as possible for our users. When you are ready to conduct a search with CheckPeople, you only need to know the person’s first and last name. That’s it! However, if the person has a very common name (i.e. John Smith), it will be beneficial to have a few other pieces of information on hand. You can narrow your search results if you know the city and state in which the person currently lives, or a city and state that they have previously lived in.
You can also do a reverse phone number lookup by simply entering the person’s cell phone or landline number. Look up any phone number to find out who it belongs to and even obtain more details about this person. Catch a mysterious repeat caller in the act or discover who your significant other keeps texting. You can even find their cyber footprint, including blogs, pictures, social media accounts and more.
Everything You Ever Wanted to Know About Earth’s Past Climates
In Silent Spring, Rachel Carson considers the Western sagebrush. “For here the natural landscape is eloquent of the interplay of forces that have created it,” she writes. “It is spread before us like the pages of an open book in which we can read why the land is what it is, and why we should preserve its integrity. But the pages lie unread.” She is lamenting the disappearance of a threatened landscape, but she may just as well be talking about markers of paleoclimate.
To know where you’re going, you have to know where you’ve been. That’s particularly true for climate scientists, who need to understand the full range of the planet’s shifts in order to chart the course of our future. But without a time machine, how do they get this kind of data?
Like Carson, they have to read the pages of the Earth. Fortunately, the Earth has kept diaries. Anything that puts down yearly layers—ocean corals, cave stalagmites, long-lived trees, tiny shelled sea creatures—faithfully records the conditions of the past. To go further, scientists dredge sediment cores and ice cores from the bottom of the ocean and the icy poles, which write their own memoirs in bursts of ash and dust and bubbles of long-trapped gas.
In a sense, then, we do have time machines: Each of these proxies tells a slightly different story, which scientists can weave together to form a more complete understanding of Earth’s past.
In March, the Smithsonian Institution’s National Museum of Natural History held a three-day Earth’s Temperature History Symposium that brought teachers, journalists, researchers and the public together to enhance their understanding of paleoclimate. During an evening lecture, Gavin Schmidt, climate modeler and director of NASA’s Goddard Institute for Space Studies, and Richard Alley, a world-famous geologist at Pennsylvania State University, explained how scientists use Earth’s past climates to improve the climate models we use to predict our future.
Here is your guide to Earth’s climate pasts—not just what we know, but how we know it.
How do we look into Earth’s past climate?
It takes a little creativity to reconstruct Earth’s past incarnations. Fortunately, scientists know the main natural factors that shape climate. They include volcanic eruptions whose ash blocks the sun, changes in Earth’s orbit that shift sunlight to different latitudes, circulation of oceans and sea ice, the layout of the continents, the size of the ozone hole, blasts of cosmic rays, and deforestation. Of these, the most important are greenhouse gases that trap the sun’s heat, particularly carbon dioxide and methane.
As Carson noted, Earth records these changes in its landscapes: in geologic layers, fossil trees, fossil shells, even crystallized rat pee—basically anything really old that gets preserved. Scientists can open up these diary pages and ask them what was going on at that time. Tree rings are particularly diligent record-keepers, recording rainfall in their annual rings ice cores can keep exquisitely detailed accounts of seasonal conditions going back nearly a million years.
Ice cores reveal annual layers of snowfall, volcanic ash and even remnants of long-dead civilizations. (NASA's Goddard / Ludovic Brucker)
What else can an ice core tell us?
“Wow, there’s so much,” says Alley, who spent five field seasons coring ice from the Greenland ice sheet. Consider what an ice core actually is: a cross-section of layers of snowfall going back millennia.
When snow blankets the ground, it contains small air spaces filled with atmospheric gases. At the poles, older layers become buried and compressed into ice, turning these spaces into bubbles of past air, as researchers Caitlin Keating-Bitonti and Lucy Chang write in Smithsonian.com. Scientists use the chemical composition of the ice itself (the ratio of the heavy and light isotopes of oxygen in H2O) to estimate temperature. In Greenland and Antarctica, scientists like Alley extract inconceivably long ice cores—some more than two miles long!
Ice cores tell us how much snow fell during a particular year. But they also reveal dust, sea salt, ash from faraway volcanic explosions, even the pollution left by Roman plumbing. “If it’s in the air it’s in the ice,” says Alley. In the best cases, we can date ice cores to their exact season and year, counting up their annual layers like tree rings. And ice cores preserve these exquisite details going back hundreds of thousands of years, making them what Alley calls “the gold standard” of paleoclimate proxies.
Wait, but isn’t Earth’s history much longer than that?
Yes, that’s right. Paleoclimate scientists need to go back millions of years—and for that we need things even older than ice cores. Fortunately, life has a long record. The fossil record of complex life reaches back to somewhere around 600 million years. That means we have definite proxies for changes in climate going back approximately that far. One of the most important is the teeth of conodonts—extinct, eel-like creatures—which go back 520 million years.
But some of the most common climate proxies at this timescale are even more miniscule. Foraminifera (known as “forams”) and diatoms are unicellular beings that tend to live on the ocean seafloor, and are often no bigger than the period at the end of this sentence. Because they are scattered all across the Earth and have been around since the Jurassic, they’ve left a robust fossil record for scientists to probe past temperatures. Using oxygen isotopes in their shells, we can reconstruct ocean temperatures going back more than 100 million years ago.
“In every outthrust headland, in every curving beach, in every grain of sand there is a story of the earth,” Carson once wrote. Those stories, it turns out, are also hiding in the waters that created those beaches, and in creatures smaller than a grain of sand.
Foraminifera. (Ernst Haeckel)
How much certainty do we have for deep past?
For paleoclimate scientists, life is crucial: if you have indicators of life on Earth, you can interpret temperature based on the distribution of organisms.
But when we’ve gone back so far that there are no longer even any conodont teeth, we’ve lost our main indicator. Past that we have to rely on the distribution of sediments, and markers of past glaciers, which we can extrapolate out to roughly indicate climate patterns. So the further back we go, the fewer proxies we have, and the less granular our understanding becomes. “It just gets foggier and foggier,” says Brian Huber , a Smithsonian paleobiologist who helped organize the symposium along with fellow paleobiologist research scientist and curator Scott Wing.
How does paleoclimate show us the importance of greenhouse gases?
Greenhouse gases, as their name suggests, work by trapping heat. Essentially, they end up forming an insulating blanket for the Earth. (You can get more into the basic chemistry here.) If you look at a graph of past Ice Ages, you can see that CO2 levels and Ice Ages (or global temperature) align. More CO2 equals warmer temperatures and less ice, and vice versa. “And we do know the direction of causation here,” Alley notes. “It is primarily from CO2 to (less) ice. Not the other way around.”
We can also look back at specific snapshots in time to see how Earth responds to past CO2 spikes. For instance, in a period of extreme warming during Earth’s Cenozoic era about 55.9 million years ago, enough carbon was released to about double the amount of CO2 in the atmosphere. The consequentially hot conditions wreaked havoc, causing massive migrations and extinctions pretty much everything that lived either moved or went extinct. Plants wilted. Oceans acidified and heated up to the temperature of bathtubs.
Unfortunately, this might be a harbinger for where we’re going. “This is what’s scary to climate modelers,” says Huber. “At the rate we’re going, we’re kind of winding back time to these periods of extreme warmth.” That’s why understanding carbon dioxide’s role in past climate change helps us forecast future climate change.
That sounds pretty bad.
I’m really impressed by how much paleoclimate data we have. But how does a climate model work?
Great question! In science, you can’t make a model unless you understand the basic principles underlying the system. So the mere fact that we’re able to make good models means that we understand how this all works. A model is essentially a simplified version of reality, based on what we know about the laws of physics and chemistry. Engineers use mathematical models to build structures that millions of people rely on, from airplanes to bridges.
Our models are based on a framework of data, much of which comes from the paleoclimate proxies scientists have collected from every corner of the world. That’s why it’s so important for data and models to be in conversation with each other. Scientists test their predictions on data from the distant past, and try to fix any discrepancies that arise. “We can go back in time and evaluate and validate the results of these models to make better predictions for what’s going to happen in the future,” says Schmidt.
It's pretty. I hear the models aren’t very accurate, though.
By their very nature, models are always wrong. Think of them as an approximation, our best guess.
But ask yourself: do these guesses give us more information than we had previously? Do they provide useful predictions we wouldn’t otherwise have? Do they allow us to ask new, better questions? “As we put all of these bits together we end up with something that looks very much like the planet,” says Schmidt. “We know it’s incomplete. We know there are things that we haven’t included, we know that we’ve put in things that are a little bit wrong. But the basic patterns we see in these models are recognizable … as the patterns that we see in satellites all the time.”
So we should trust them to predict the future?
The models faithfully reproduce the patterns we see in Earth’s past, present—and in some cases, future. We are now at the point where we can compare early climate models—those of the late 1980s and 1990s that Schmidt’s team at NASA worked on—to reality. “When I was a student, the early models told us how it would warm,” says Alley. “That is happening. The models are successfully predictive as well as explanatory: they work.” Depending on where you stand, that might make you say “Oh goody! We were right!” or “Oh no! We were right.”
To check models’ accuracy, researchers go right back to the paleoclimate data that Alley and others have collected. They run models into the distant past, and compare them to the data that they actually have.
“If we can reproduce ancient past climates where we know what happened, that tells us that those models are a really good tool for us to know what’s going to happen in the future,” says Linda Ivany, a paleoclimate scientist at Syracuse University. Ivany’s research proxies are ancient clams, whose shells record not only yearly conditions but individual winters and summers going back 300 million years—making them a valuable way to check models. “The better the models get at recovering the past,” she says, “the better they’re going to be at predicting the future.”
Paleoclimate shows us that Earth’s climate has changed dramatically. Doesn’t that mean that, in a relative sense, today’s changes aren’t a big deal?
When Richard Alley tries to explain the gravity of manmade climate change, he often invokes a particular annual phenomenon: the wildfires that blaze in the hills of Los Angeles every year. These fires are predictable, cyclical, natural. But it’d be crazy to say that, since fires are the norm, it’s fine to let arsonists set fires too. Similarly, the fact that climate has changed over millions of years doesn’t mean that manmade greenhouse gases aren’t a serious global threat.
"Our civilization is predicated on stable climate and sea level," says Wing, "and everything we know from the past says that when you put a lot of carbon in the atmosphere, climate and sea level change radically."
Since the Industrial Revolution, human activities have helped warm the globe 2 degrees F, one-quarter of what Schmidt deems an “Ice Age Unit”—the temperature change that the Earth goes through between an Ice Age and a non-Ice Age. Today’s models predict another 2 to 6 degrees Celsius of warming by 2100—at least 20 times faster than past bouts of warming over the past 2 million years.
Of course there are uncertainties: “We could have a debate about whether we’re being a little too optimistic or not,” says Alley. “But not much debate about whether we’re being too scary or not.” Considering how right we were before, we should ignore history at our own peril.
About Rachel E. Gross
Rachel is the Science Editor, covering stories behind new discoveries and the debates that shape our understanding of the world. Before coming to Smithsonian, she covered science for Slate, Wired, and The New York Times.
The Middle Colonies
The Middle Colonies of New York, New Jersey, Pennsylvania, and Delaware offered fertile farmland and natural harbors. Farmers grew grain and raised livestock. The Middle Colonies also practiced trade like New England, but typically they were trading raw materials for manufactured items.
One important event that happened in the Middle Colonies during the colonial period was the Zenger Trial in 1735. John Peter Zenger was arrested for writing against the royal governor of New York. Zenger was defended by Andrew Hamilton and found not guilty helping to establish the idea of freedom of the press.
The Dutch owned a colony called New Netherland. In 1664, Charles II granted New Netherland to his brother James, Duke of York. He just had to take it from the Dutch. He arrived with a fleet. The Dutch surrendered without a fight.
The Duke of York granted some land to Sir George Carteret and Lord John Berkeley, who named their colony New Jersey. They provided liberal grants of land and freedom of religion. The two parts of the colony were not united into a royal colony until 1702.
The Quakers were persecuted by the English and wished to have a colony in America.
William Penn received a grant which the King called Pennsylvania. Penn wished to begin a “holy experiment.” The first settlement was Philadelphia. This colony quickly became one of the largest in the New World.
Declaration of Independence was written and signed in Pennsylvania. The Continental Congress met in Philadelphia until it was captured by British General William Howe in 1777 and forced to move to York.
When the Duke of York got New Netherland, he also received New Sweden which had been founded by Peter Minuit. He renamed this area, Delaware. This area became part of Pennsylvania until 1703 when it created its own legislature.
Everything you wanted to know about Delaware, history, economy people and more - History
DELJIS remains fully operational however, most if not all DELJIS staff are working remotely.
We are not accepting any public visitors at this time.
We ask that police officers and/or criminal justice staff utilize the DELJIS helpdesk resource if at all possible so we can adequately log any issues.
Training is being conducted virtually to the extent possible.If you are scheduled for training, and have questions, please email the training group at the address indicated in the DELJIS Web Portal.
ePayment of Traffic Tickets Available Now!
- Click Here
Delaware Launches Statewide Victim Notification Program
- VINE Information
Message from Executive Director (Earl McCloskey)
I am pleased to welcome you to the DELJIS home page. I hope that each time you visit this site you will learn more about DELJIS. DELJIS has a unique mission to, "serve those who serve others." Keep in mind that information empowers its authorized users.
On behalf of the DELJIS Board of Managers and myself, we invite you to explore our home page. This site will identify and better explain the systems DELJIS supports within the criminal justice community. Additionally, you will see why Delaware has the honor of having the most integrated criminal justice system in the nation.
If you have any issues, comments, or questions concerning DELJIS and its purpose, mission, or function you can e-mail me directly: - Earl McCloskey
As strong as death
Everything is calculated so that the work resembles death itself: it is both pathetic and terrifying, calm and terrible. Written for four soloists (soprano, contralto, tenor, and bass), choir and symphonic orchestra, Mozart excluded all wind instruments (flute and oboe), considered too joyful, in order to only keep the basset horn, an ancestor of the clarinet, with a more muted sound. Sad and solemn, the orchestra is perfect for a requiem mass, and Mozart’s writing itself is sober, even austere: there are no sparkly effects or virtuosic solos.
The spectacular is to be found elsewhere: the choir is enhanced and its power is allowed to be fully felt. In the Dies Irae, the judgment day, a massive storm hits: the terrible voices of the choir show God’s divine wrath coming to man, followed by attempts to soften this anger, and then again cries of terror… Everything trembles in angst, fever and impatience. Mozart’s last composition achieves a point of sublime excellence.
Pour afficher ce contenu Youtube, vous devez accepter les cookies Publicité.
Ces cookies permettent à nos partenaires de vous proposer des publicités et des contenus personnalisés en fonction de votre navigation, de votre profil et de vos centres d'intérêt.
Everything you wanted to know about Delaware, history, economy people and more - History
Spondylolisthesis is a medical term that describes an abnormal anatomic alignment between two bones in the spine. This anatomic abnormality has been around since antiquity. It was first described in the modern medical literature by a Belgian obstetrician named Dr. Herbinaux. In 1782, Dr. Herbinaux noticed that the abnormal alignment of the lumbar spine and pelvis in very severe cases made natural childbirth difficult. He was the first one to name this condition in which one vertebral body is slipped forward with respect to the one underneath it.
The term spondylolisthesis comes from two greek words: “spondy” (σπονδυλος) which means “vertebra” and “listhesis” (ὁλισθος) which means “a slip”.
How common is spondylolisthesis?
Spondylolisthesis most commonly affects the lower lumbar spine, typically at the L4/5 or L5/S1 levels. Spondylolisthesis is a very common condition, occurring in about 5% of the population. The most common type of spondylolisthesis is a degenerative slip that occurs at the L4/5 level. This type of slip is caused by degeneration of the intervertebral disk and the facet joints. Natural aging results in an increase in the “sloppiness” of the joint, much like a worn bushing in a car. Here are two images that depict the changes that occur as the disk degenerates. The gel-like substance inside the disk shrinks, the edges of the disk become irregular, and bone spurs develop.
In this series of images, I use a CV joint from a car to illustrate how the spine is a mechanical joint and many years of “wear and tear” will cause the joint to become sloppy.
The Medical Definition of a degenerative spondylolisthesis
A recent clinical consensus paper was produced by the North American Spine Society will be referenced throughout this guide. Their version of the “best working definition” of a degenerative lumbar spondylolisthesis is as follows: an acquired anterior displacement of one vertebra over the subjacent vertebrae, associated with degenerative changes, without an associated disruption or defect in the vertebral ring.
The key elements in this definition — anterior slip, degenerative change, and no disruption of the vertebral ring are easy to demonstrate in a typical case of spondylolisthesis. As the disk deteriorates it becomes less capable of absorbing all of the forces of normal human movement. Because the joint has increased “play” or “sloppiness” L4 starts to slip forward with respect to L5. Here are X-rays and an MRI scan of a typical case of a grade 1 spondylolisthesis. Flexion and extension X-rays are often used to evaluate how much abnormal motion occurs at the level of the spondylolisthesis.
The second most common type of spondylolisthesis that we see occurs at L5/S1. This condition is especially common in people who have repetitively extended their spine during athletics in adolescence. The theory is that repetitive hyperextension of the spine during athletics results in a stress fracture. This stress fracture called a spondylolysis. The stress fracture occurs in a part of the vertebral body called the pars inter-articularis which disrupts the continuity of the vertebral ring. The lack of a connection between the posterior and anterior parts of the L5 vertebral body allows the L5 vertebral body to slip forwards with respect to S1. The association between adolescent athletics and this condition is very strong. About 95% of competitive gymnasts and about 35% of competitive football players have X-ray evidence of the stress fracture that may result in a spondylolisthesis later on in life.
This condition usually develops in two stages. First, the patient has an episode of low back pain during their adolescence which is when the stress fracture of the pars interarticularis occurs. Then as the disk starts to degenerate later in life, they begin to complain of low back and leg pain. In contrast to a degenerative spondylolisthesis, this type of slip does involve a disruption of the vertebral ring, so this is often called an “isthmic” spondylolisthesis
Symptoms of spondylolisthesis
Patients with spondylolisthesis complain of low back pain and pain along the course of the nerves that are pinched by the spondylolisthesis. The narrowing of the normal space available for the nerve roots in the spinal canal is called stenosis. The back pain typically occurs in the area of the lower lumbar spine and often radiates around the abdomen and into the buttocks. The location of the nerve root pain depends upon where the slip is occurring and where the nerve roots are compressed.
Nerve root compression due to stenosis is called a radiculopathy: radix is the greek word for “root” and pathos a word for “a disease of”. Pain and numbness in the legs as the result of a spondylolisthesis occurs in patterns called a radiculopathy that are very characteristic. The human body is divided into a series of dermatomes which can be visualized as a map of where the nerves travel after the leave the spinal canal. When the root of the nerve is affected, the entire course of the nerve is typically painful, numb, or the skin in this area is unusually sensitive. For example, here is a map of the normal dermatomes of the body, and then three diagrams of an L4, L5, and S1 radiculopathy. Patients with a spondylolisthesis at L4/5 usually have L5 nerve root pain due to compression of the L5 nerve root in the neural foramen. Patients with a slip at L5/S1 usually have both L5 nerve and S1 root pain due to tension on the nerve roots. For example, a patient with an L4/5 spondylolisthesis will usually describe low back pain at the base of the spine, radiating into the buttocks. There is usually also pain and numbness along the sides of the legs, down the front and sides of the calves, with numbness and tingling in the feet.
If your major problem is pain and numbness in the legs, and especially if it is only affecting one leg, you may be a good candidate for a microscopic decompression instead of a fusion. If you are interested in exploring this option, I may be able to review your MRI scan for you.
The pain that is associated with spondylolisthesis is variable. It is often worse with standing. Many patients find that the length of time they can walk comfortably gets shorter and shorter as the disease progresses. We call this finding “limited walking endurance”. This is often an indicator of how severely the patient is affected and how much nerve root compression they have. Patients who are able to walk for more than an hour rarely need operative treatment. Those who can only walk for a few hundred yards before they are limited by back and leg pain are more likely to require surgery. These patients will often experience substantial relief once their spondylolisthesis is corrected. While the pain associated with a spondylolisthesis is usually worse when the patient is on their feet, many patients have a hard time sleeping at night because the nerve root pain keeps them awake.
Xray and MRI findings in spondylolisthesis.
The best test for diagnosing a spondylolisthesis is a lateral Xray of the lumbar spine with the patient standing. It is important that the patient is standing because there are some slips that return to their normal position when the patient lies down. This is why some cases of spondylolisthesis are not apparent on supine X-rays or an MRI scan. The best test for evaluating the degree of nerve root compression and spinal stenosis caused by spondylolisthesis is an MRI scan of the lumbar spine.
Here are a series of X-rays and MRI scans showing the relevant anatomic finding in a typical L4/5 degenerative spondylolisthesis. Click on these images to enlarge them to full size
And here are the X-rays and MRI scans of a patient with an L5/S1 spondylolisthesis with bilateral pars defects.
Non-operative treatment of spondylolisthesis
Physical Therapy: While it may not be possible to reverse the degenerative changes that occur with aging, it is possible to strengthen the muscles that surround the spine. I have written a blog post about this particular point, which can be read here: reversing spondylolisthesis
PT helps to stabilize the lumbar spine and will often result in a decrease in symptoms of low back and leg pain to the point where surgery becomes unnecessary. This type of therapy MUST emphasize active rehabilitation, which means that the patient must work actively to strengthen the muscles of the abdomen, low back, and core. Massage, hot pack treatments, and electrical stimulation may feel good at the time, but their effects are usually temporary. While massage feels great, it usually does NOT result in sustained relief. The type of therapy that we employ emphasizes core conditioning and strengthening and our therapists will instruct you on how to do these exercises properly. If your symptoms are relatively mild and you are still able to exercise, hike, and play some sports, then often a Pilates or a Yoga program may be very beneficial, less costly, and more convenient than going to a physical therapist.
Non-steroidal pain relievers like Aspirin, Tylenol, Motrin, and Ibuprofen are very helpful in the management of spondylolisthesis. The medications can calm down the inflammation that accompanies degenerative disk disease. This often makes it possible to participate in physical therapy with less pain. If you can do PT, it makes it possible to work harder to strengthen the muscles of the low back and abdomen.
Selective Nerve Root Blocks: In our clinic we have specialists who perform selective nerve root blocks with injectable medications like Cortisone and Kenalog. These are much stronger than the anti-inflammatories you can take by mouth. These injections are performed in the surgical center and are done using an intra-operative X-ray machine to make sure that the medication is injected in the same area where the nerve root compression is occurring. In our experience, nerve root blocks are very helpful for patients. They will often result in a sufficient reduction in pain so that physical therapy is tolerable. The block may also interrupt the “cycle of inflammation” to the point where the symptoms are manageable and surgery can be avoided indefinitely.
Why you should avoid narcotics
In our experience, using narcotic pain medications on a daily basis for the treatment of the pain associated with a spondylolisthesis is a bad idea. Because spondylolisthesis is a condition that tends to worsen with time, most people who start taking narcotics find it very difficult to stop. The use of narcotic pain medications for an open-ended diagnosis is dangerous. This is because there is not a defined point in the future when we know that the pain will spontaneously resolve. For example, if a patient has a fracture, we know that the pain will subside once the fracture heals. However, with a spondylolisthesis, because there is not a possibility of spontaneous correction, the patient will continue to perceive a need for narcotics on a regular basis. This quickly leads to tolerance as the medications become less effective with time and their routine use becomes habit forming. For more information on my philosophy about the use of narcotic pain medications, click here.
What the establishment says about non-operative care for spondylolisthesis
The North American Spine Society’s consensus statement on non-operative care for spondylolisthesis is a follows: The majority of patients with symptomatic degenerative lumbar spondylolisthesis and an absence of neurologic deficits will do well with conservative care. Patients who present with sensory changes, muscle weakness, [or a short walking endurance] are more likely to develop progressive functional decline without surgery. Progression of slip correlates with jobs that require repetitive anterior flexion of the spine. Slip progression is less likely to occur when the disc has lost over 80% of its native height and intervertebral osteophytes have formed. Progression of clinical symptoms does not correlate with progression of the slip.
Surgery for spondylolisthesis: do you need it?
Here is what the North American Spine Society has to say: Surgery is recommended for treatment of patients with symptomatic spinal stenosis associated with low grade degenerative spondylolisthesis whose symptoms have been recalcitrant to a trial of medical and interventional treatment. In our clinic we agree with this statement.
What this means to us is that patients who have symptoms that can be clearly attributed to their spondylolisthesis should first be educated about their condition. Next they should consider physical therapy and lifestyle changes that we believe are associated with improvements in back pain. If they continue to have pain they should consider a selective nerve root block to temporarily reduce the inflammation in the nerve roots — as long as this is seen as a bridge to making physical therapy more tolerable. Surgery should only be considered when the patient has continued symptoms that do not improve with physical therapy or medical management.
Our technique for the surgical correction of spondylolisthesis is designed to achieve four goals
1. relieve the nerve root compression that is causing pain and numbness in the legs
2. stabilize the unstable spinal segment that is slipping, only if necessary
3. improve the alignment of the spinal canal
4. provide the patient with a durable solution that will improve their quality of life for years to come.
While there is a great deal of debate about the best surgical technique for the treatment of spondylolisthesis, the NASS clinical guidelines do state that surgical decompression with fusion is recommended for the treatment of patients with symptomatic spinal stenosis and degenerative lumbar spondylolisthesis…and that …decompression and fusion is recommended as a means to provide satisfactory long-term (greater than 4+ years) results for the patient. For example, on a recent Spine Surgery Board Certification Examination administered by the American Academy of Neurological Surgeons, the following question was asked: A 47 year old dentist presents with a 5 year history of intractable low back pain refractory to several courses of physical therapy and numerous medications. He has recently developed bilateral L5 radiculopathy. MR imaging demonstrates grade II anterolisthesis of L4 on L5 with resulting L4-5 central canal stenosis and bilateral neuroforaminal stenosis. The BEST treatment option is:
- dorsal column stimulator
- anterior lumbar interbody cage fusion
- laminectomy and pedicle screw fusion
- epidural steroid injection
- laminectomy with facetectomy
The correct answer, according to the AANS, is #3. Here is their explanation: This patient has failed reasonable attempts at non-operative management and has an anatomical abnormality that corresponds to his clinical symptomatology. Surgical correction is the best option. Decompression alone in the presence of spondylolisthesis in a relatively young patient is associated with a high incidence of progressive listhesis and worsening pain.
Here’s where I disagree. I think that it in carefully selected patients, a microscopic decompression with meticulous physical therapy and rehabilitation can result is excellent clinical results. When I am able to alleviate someone’s leg pain so that they can go back to working out and keep their core strong, they are happy.
I’d be happy to give you second opinion if you are interested in whether or not a fusion is necessary in your case
In the meantime, here is a series of pictures from our operating room during correction of a spondylolisthesis of the spine using a traditional approach…
Here are a series of x-rays that demonstrate the correction of spondylolisthesis with a decompression and fusion of the slip performed in our clinic in Monterey, California. You can click on each of these Xrays to enlarge them to full size.
L4.5 degenerative spondylolisthesis repaired with an L4.5 lumbar decompression, instrumented fusion, and reduction of spondylolisthesis.
L5/S1 isthmic spondylolisthesis repaired with an L5/S1 lumbar decompression, instrumented fusion, and reduction of spondylolisthesis.
I’ve also got a large number of patients that haven’t needed a stabilization. Instead, I’ve done a microscopic decompression for them, especially if they only have pain and numbness in one leg. If they are able to decrease the chance of future progression of the spondylolisthesis with lumbar spine strengthening exercises, they are delighted with the opportunity to live without a fusion every day.
If you’ve already had an MRI scan and are intrested in discussing your options, I will review your MRI scan for and tell you whether or not I think a microscopic decompression rather than a fusion will work in your case.
To learn more about your options for non-fusion treatment of spondylolisthesis, click here: MRI review.
Learn More About The Lenni Lenapes
Lenape Indian Tribe An overview of the Leni Lenape people, their language and history.
Lenape Language Resources Lanape language samples, articles, and indexed list of links.
Lenape Delaware History and Culture Related links about the Lenni Lenape people past and present.
Lenape Words Lenape Indian vocabulary lists.
Native Languages of the Americas website © 1998-2020 Contact us Follow our blog
Trait 5: Surround Sound
Gen Z may appear to be obsessed with their screens, but they value audio as an escape from visual stimulation overload.
Audio isn’t just background noise, said 50% of the study respondents it plays a huge role in their everyday lives. So silence can be golden too. To raise awareness of the International Day for the Elimination of Violence Against Women, Marie Claire ran a campaign of 30-second silent spots on Spotify. Listeners assumed there was a glitch and looked at their phones, only to see a message explaining the danger of staying silent about violence. Powerful, impactful communications such as this leave a lasting impression with Gen Z.
Scroll down to the infographic below to see more of the Culture Next Trends study’s most interesting insights. And millennials, keep your FOMO in check: we took a look at your generation, too.