My article from this morning on Scientific American Guest Blogs
Living Interplanetary Space Flight Experiment–or Why Were All the Strange Creatures on the Shuttle Endeavour? by David Warmflash
Wednesday, June 1, 2011
Tuesday, May 31, 2011
How the Space Shuttle Endeavour got Her British Name
But did you ever wonder why NASA's fifth orbiting space shuttle acquired her name with the British spelling? 10 seconds of research on this topic lead me to the orbiter information page on the NASA Kennedy Space Center website. And therein lies the answer:
NASA's Endeavour was named for the HMS Endeavour:
"Endeavour was named after a ship chartered to traverse the South Pacific in 1768 and captained by 18th century British explorer James Cook, an experienced seaman, navigator and amateur astronomer. He commanded a crew of 93 men, including 11 scientists and artists.
"Cook's main objective, tasked by the British Admiralty and the Royal Society, was to observe the Transit of Venus at Tahiti. This reading enabled astronomers to find the distance of the Sun from the Earth, which then could be used as a unit of measurement in calculating the parameters of the universe..."
149 million kilometers, or 93 million miles from Earth. This is equal to about eight light minutes, which is to say that it takes light eight minutes to travel from the surface of the Sun to Earth. The second planet from the Sun, just slightly less massive than Earth, and the closest planet to Earth, Venus is called Earth’s sister planet. Despite the proximity, due to the thick cloud layer in the Venusian atmosphere, humanity would know nothing about the environment at the surface of Venus until the advent of space probes in the middle of the 20th century. But the basics of her movement around the Sun, and the distances between the Sun, Venus, and Earth were worked out based on the measurements taken by the scientists on Cook’s voyage.
The NASA article goes on:
"Cook's achievements on Endeavour were numerous, including the accurate charting of New Zealand and Australia and successfully navigating the Great Barrier Reef. Thousands of new plant specimens and animal species were observed and illustrated on this maiden voyage. Cook also established the usefulness of including scientists on voyages of exploration."
So now we know. Time to add the British spelling to the computer's dictionary.
Monday, May 30, 2011
LIFE Experiment to Return to Earth when Space Shuttle Endeavour's Last Flight Touches Down
Adapted from The Planetary Society's pre-mission press release
Late Sunday night, the space shuttle Endeavour undocked from the International Space Station. Commanded by Mark Kelly, husband of Congresswoman Gabriella Giffords, the Endeavour is carrying not only human astronauts but a legion of microscopic passengers in the Planetary Society's Shuttle LIFE experiment. Landing is scheduled for 2:32 am Wednesday at NASA's Kennedy Space center, in Florida.
Can life naturally transfer from planet to planet? LIFE, the Living Interplanetary Flight Experiment, was developed to test aspects of the transpermia hypothesis -- the ability of microbial life to survive an interplanetary voyage. The largest of the LIFE organisms launching on the shuttle will be tardigrades, or water bears, which are no bigger than the head of a pin.
Shuttle-LIFE will serve as a test run for Phobos LIFE, a larger collection of organisms that the Planetary Society will send on a three-year trip aboard a Russian spacecraft to the Martian moon Phobos and back to Earth in a capsule that will simulate a meteoroid. Phobos LIFE is set to launch at the end of 2011.
"One cannot help but wonder if it's possible for a living organism to make the trip from one planet to another?" said Bill Nye, Executive Director of the Planetary Society. "How about from Mars to the Earth?"
Shuttle LIFE's Main Goals
* Testing the effects of low Earth orbit spaceflight on the organisms,
* Providing a comparison for the upcoming long duration Phobos LIFE mission,
* Serving as a "dress rehearsal" for Phobos-LIFE, complete with loading, unloading, and analyzing organisms in laboratory conditions, and
* Engaging the public in the exciting discussion of whether life might be able to travel naturally between planets.
Over 16 days, Shuttle-LIFE has been testing the effects of low-Earth orbit spaceflight on five diverse species of microorganisms packed in tiny, heat-sealed, Delrin plastic sample tubes. For the Phobos mission, the miniature sample tubes will be packed into a nearly indestructible titanium capsule that looks like a small hockey puck.
The five life forms being flown in Shuttle-LIFE are Tardigrades; the bacteria Deinococcus radiodurans and Bacillus subtilis; and the archaea Haloarcula marismortui and Pyrococcus furiosus. A passenger manifest explains what characteristics of the different microorganisms - such as resistance to radiation or extreme hardiness - made them good choices for space travel.
"The millions of tiny space voyagers in Shuttle-LIFE are set to take a big journey and give us information about life in space, and they'll do it all without any checked baggage," said Bruce Betts, the Planetary Society's Director of Projects.
Partners For Shuttle LIFE
Partners on Shuttle LIFE, who will be providing organisms and pre and post flight analyses, are a team at ATCC in Manassas, Virginia led by Tim Lilburn and Amy Smith; Ingemar Joensson at Kristianstad University in Sweden; and a German DLR team, led by Petra Rettberg and Marko Wassmann. Phobos LIFE science Principal Investigator David Warmflash from Portland State University is involved with the science planning and analysis. Sample tubes were produced by Lindel Engineering in Tucson, Arizona based on designs by Bud Fraze.
Shuttle LIFE will fly in a flight-proven unit from Instrumentation Technology Associates, Inc. (ITA) as part of CREST-1 (Commercial Reusable Experiments for Science & Technology), manifested on STS-134 through NanoRacks LLC, working in partnership with NASA.
The Planetary Society:
The Planetary Society has inspired millions of people to explore other worlds and seek other life. Today, its international membership makes the non-governmental Planetary Society the largest space interest group in the world. Carl Sagan, Bruce Murray and Louis Friedman founded The Planetary Society in 1980. Bill Nye, a long time member of the Planetary Society's Board, is now the Executive Director.
Monday, May 23, 2011
Radionuclide Imaging to Assess Function of the Heart
Elements and molecules that emit ionizing radiation are known as radionuclides. This radioactivity is in the form of subatomic particles or gamma rays. Depending on the type of radioactive emission and other characteristics of the compound, different agents can be used for different purposes. In scintigraphy, radiation from radionuclides introduced into a patient are detected by special sensors called gamma cameras. The data then are processed to create two-dimensional images. In SPECT, sensors are arranged in a variety of positions around the patient and data are processed into 3 dimensional images.
In positron emission tomography (PET), the radionuclide is a compound that the body uses -which is to say a metabolite- that has been altered to include an atom that emits positrons. A positron is a subatomic particle that has the same mass as an electron, but is positively charged. It is the antimatter counterpart of an electron. When a positron is emitted and meets up with electrons from other sources, annihilation of both particles takes place and they are converted into gamma rays according to Einstein’s equation E = MC^2.
Cardiac radionuclide imaging uses radionuclides along with gamma cameras to obtain information on the function of the heart. It can be used clinically to diagnose and assess various medical conditions. In cardiac imaging, radionuclides are introduced into the body by injection. Gamma radiation, produced directly by the radionuclides or indirectly as a result of their presence, is then detected by special sensors. Data are then processed to produce an image.
Radionuclides used in cardiac imaging include technetium-99 and thallium-201. The number following the name of the element represents the total of the number of protons and neutrons in the nucleus of the element's atoms. Radionuclides can be useful in assessing various aspects of cardiac function. The flow of blood through the heart muscle (myocardium) can be tracked as the sensors, known as gamma cameras (cameras that detect gamma rays), track radiation from the radionuclide flowing in myocardial blood vessels. Coronary artery disease can be evaluated as well. In this case the flow of radionuclides, and therefore the blood, is tracked through the coronary arteries, the main blood vessels that nourish the heart. Similarly, the extent of damage to the heart following a myocardial infarction (interruption of blood flow to an area of the heart muscle) can be evaluated, as can the improvement of blood flow following coronary artery bypass surgery (CABG). Together with electrocardiography (ECG) radionuclides also can be used to assess how well the heart muscle moves.
In positron emission tomography (PET), the radionuclide is a compound that the body uses -which is to say a metabolite- that has been altered to include an atom that emits positrons. A positron is a subatomic particle that has the same mass as an electron, but is positively charged. It is the antimatter counterpart of an electron. When a positron is emitted and meets up with electrons from other sources, annihilation of both particles takes place and they are converted into gamma rays according to Einstein’s equation E = MC^2.
Cardiac radionuclide imaging uses radionuclides along with gamma cameras to obtain information on the function of the heart. It can be used clinically to diagnose and assess various medical conditions. In cardiac imaging, radionuclides are introduced into the body by injection. Gamma radiation, produced directly by the radionuclides or indirectly as a result of their presence, is then detected by special sensors. Data are then processed to produce an image.
Radionuclides used in cardiac imaging include technetium-99 and thallium-201. The number following the name of the element represents the total of the number of protons and neutrons in the nucleus of the element's atoms. Radionuclides can be useful in assessing various aspects of cardiac function. The flow of blood through the heart muscle (myocardium) can be tracked as the sensors, known as gamma cameras (cameras that detect gamma rays), track radiation from the radionuclide flowing in myocardial blood vessels. Coronary artery disease can be evaluated as well. In this case the flow of radionuclides, and therefore the blood, is tracked through the coronary arteries, the main blood vessels that nourish the heart. Similarly, the extent of damage to the heart following a myocardial infarction (interruption of blood flow to an area of the heart muscle) can be evaluated, as can the improvement of blood flow following coronary artery bypass surgery (CABG). Together with electrocardiography (ECG) radionuclides also can be used to assess how well the heart muscle moves.
Canine Osteosarcoma: Bone Cancer in Dogs
Although many types of bone cancer can develop in dogs, osteosarcoma (OSA) is the most common one. Usually occurring in the legs, osteosarcoma represents about 75-80 percent of malignant canine bone tumors, though less than five percent of canine tumors overall. Osteosarcoma tends to develop in the legs, possibly because it develops from cells that are involved in the manufacture of new bone, a process that occurs more often and more rapidly in long bones. Nevertheless, osteosarcoma may also develop elsewhere, such as in the spine, bones of the cranium, and rib cage. The incidence of osteosarcoma is higher in larger dog breeds than smaller dogs. Though it may appear in a dog of any age, osteosarcoma tends to affect older dogs, which is in sharp contrast with human osteosarcoma which usually strikes children and young adults, the most famous case being Ted Kennedy Jr. (son of the late Senator Ted Kennedy), who survived, but lost his leg to the disease.
Basic Definitions: Tumors, Cancer, Benign, Malignant, Metastasis, Sarcoma, Carcinoma
The word tumor refers to a growth that is abnormal compared to the surrounding tissue. Abnormally rapid and uncontrolled reproduction of cells can lead either to a benign tumor, or a malignant tumor. Malignant tumors are those which are more aggressive, do more hard to the tissue in which they are located, and usually (although there are a few exceptions) have a high chance of metastasis -spreading to remote areas of the body and seeding new tumors there. A sarcoma is a malignant tumor that develops either in connective tissue (which includes bone and cartilage tissue among others), or in muscle tissue. A carcinoma is a malignant tumor that develops in epithelial tissue, the type of tissue which lines surfaces. Since bones have epithelial tissue as part of their lining, carcinomas as well as sarcomas are possible.
Types of Malignant Tumors that can occur in Canine Bones
Osteosarcoma, the most common bone cancer, develops from cells that essentially are cousins of the cells that manufacture the bone material itself, the cells known as osteoblasts. Although sometimes dog owners are told osteoblasts actually produce the cancer, this is not exactly true. In fact, there are several subcategories of osteosarcoma, including osteoblastic, chondroblastic, fibroblastic, and many more. These are names of different types of cells that are present in bone, and the tumors are named accordingly. If the cells of a tumor look like osteoblasts, it is called osteoblastic. If they look like chondroblasts -the cells which produce cartilage- it is called chondroblastic, and so on. It is known, however, that sarcomas in bone result not from osteoblasts, chondroblasts, and the others per se, but from the stem cells that produce them. Stem cells are generalized cells which can develop into various cell types. In bone and cartilage, one type of stem cell that is present during development of the embryo can develop into several connective cell types as it reproduces. If cell reproduction goes a certain way, osteoblasts are produced. If it goes another way, chondroblasts are produced. But if a line of stem cells is somewhere along the way to producing osteoblasts and something goes wrong, cancer cells may be produce that look a lot like osteoblasts, but don’t act like osteoblasts. This is why it is more correct to say that the cells of osteoblastic osteosarcoma are cousins of the bone-making cells that we call osteoblasts.
Now, chondrosarcoma is the second most common malignant tumor that can develop in dog bones. As you may have guessed from the name, chondrosarcoma is a sarcoma of cartilage cells. Though less common than osteosarcoma, it is nearly as aggressive. As in the case of osteosarcoma, the diseased cells all begin as the same type of stem cells that also produced healthy osteoblasts and chondroblasts and a variety of other cells. Chondrosarcoma tends to occur in flat bones and the rib cage, since these are places where there is more cartilage compared to bone, in contrast to long bones which have cartilage concentrated at the ends. Sarcomas of different types can occur in other areas of bone too, for instance in the linings of joint capsules. Hemangiosarcoma and fibrosarcoma are two other sarcomas that can develop in dog bones. In the case of carcinomas, a subtype called squamous cell carcinoma can develop in the outer cell layer of canine bones, known as the periosteum. But again, bone cancer in dogs most often means osteosarcoma.
Etiology of Canine Osteosarcoma
What causes osteosarcoma, both in humans and dogs? Nobody is exactly sure, though many have speculated about possible mechanisms. Some have hypothesized cell damage due to ionizing radiation or carcinogenic chemicals as a possible causes. Nutritional factors have been studied, since the tumor usually develops near the region of the long bones where growth takes place (the growth plates). Other possibilities include trauma to the bones, and damage resulting from implants. Studies have been conducted to determine whether hormonal factors may be at play, perhaps in connection with neutering of the dogs. Genetic predisposition is another possibility; the presence of abnormal copies of a gene known as p53, which normally inhibits tumor development, correlates with increased osteosarcoma incidence.
Presentation and Diagnosis of Canine Osteosarcoma
Osteosarcoma in dogs typically presents as swelling, not always with pain initially, though pain will develop at some point. The dog is lame in the affected leg. The leg may fracture. On account of the pain, the dog will lose his or her appetite and lose weight, become lethargic, and often develop insomnia and be generally irritable. Unfortunately, by the time these symptoms appear, the tumor already has destroyed much of the bone in which it began. Even worse, in more than 90 percent of cases, the tumor already has metastasized to other bones and to the lungs.
X-rays can reveal visual features that are typical of an osteosarcoma in a bone. Together with clinical signs, usually this is enough to confirm a diagnosis. If needed though, a biopsy can be taken. In biopsy. a sample of the tumor is removed surgically, then examined by a pathologist.
Treatments for Canine Osteosarcoma
If osteosarcoma is detected early, there are treatments that not only can extend a dog’s life but can reduce the dog’s suffering. The treatments include surgery and chemotherapy, which usually means that the limb is amputated, followed by chemotherapy. If the cancer is in an early stage, amputation can actually save the dog’s life by preventing it from metastasizing to other parts of the body. Approximately 60 percent of dogs treated with amputation and chemotherapy for osteosarcoma are alive one year later, and forty percent two years later. In unusual cases in which only a tiny, isolated part of a bone is affected, it is possible to remove the tumor without amputation. Radiation treatment is used only to shrink an osteosarcoma in cases when it is so big that surgery is not possible.
Basic Definitions: Tumors, Cancer, Benign, Malignant, Metastasis, Sarcoma, Carcinoma
The word tumor refers to a growth that is abnormal compared to the surrounding tissue. Abnormally rapid and uncontrolled reproduction of cells can lead either to a benign tumor, or a malignant tumor. Malignant tumors are those which are more aggressive, do more hard to the tissue in which they are located, and usually (although there are a few exceptions) have a high chance of metastasis -spreading to remote areas of the body and seeding new tumors there. A sarcoma is a malignant tumor that develops either in connective tissue (which includes bone and cartilage tissue among others), or in muscle tissue. A carcinoma is a malignant tumor that develops in epithelial tissue, the type of tissue which lines surfaces. Since bones have epithelial tissue as part of their lining, carcinomas as well as sarcomas are possible.
Types of Malignant Tumors that can occur in Canine Bones
Osteosarcoma, the most common bone cancer, develops from cells that essentially are cousins of the cells that manufacture the bone material itself, the cells known as osteoblasts. Although sometimes dog owners are told osteoblasts actually produce the cancer, this is not exactly true. In fact, there are several subcategories of osteosarcoma, including osteoblastic, chondroblastic, fibroblastic, and many more. These are names of different types of cells that are present in bone, and the tumors are named accordingly. If the cells of a tumor look like osteoblasts, it is called osteoblastic. If they look like chondroblasts -the cells which produce cartilage- it is called chondroblastic, and so on. It is known, however, that sarcomas in bone result not from osteoblasts, chondroblasts, and the others per se, but from the stem cells that produce them. Stem cells are generalized cells which can develop into various cell types. In bone and cartilage, one type of stem cell that is present during development of the embryo can develop into several connective cell types as it reproduces. If cell reproduction goes a certain way, osteoblasts are produced. If it goes another way, chondroblasts are produced. But if a line of stem cells is somewhere along the way to producing osteoblasts and something goes wrong, cancer cells may be produce that look a lot like osteoblasts, but don’t act like osteoblasts. This is why it is more correct to say that the cells of osteoblastic osteosarcoma are cousins of the bone-making cells that we call osteoblasts.
Now, chondrosarcoma is the second most common malignant tumor that can develop in dog bones. As you may have guessed from the name, chondrosarcoma is a sarcoma of cartilage cells. Though less common than osteosarcoma, it is nearly as aggressive. As in the case of osteosarcoma, the diseased cells all begin as the same type of stem cells that also produced healthy osteoblasts and chondroblasts and a variety of other cells. Chondrosarcoma tends to occur in flat bones and the rib cage, since these are places where there is more cartilage compared to bone, in contrast to long bones which have cartilage concentrated at the ends. Sarcomas of different types can occur in other areas of bone too, for instance in the linings of joint capsules. Hemangiosarcoma and fibrosarcoma are two other sarcomas that can develop in dog bones. In the case of carcinomas, a subtype called squamous cell carcinoma can develop in the outer cell layer of canine bones, known as the periosteum. But again, bone cancer in dogs most often means osteosarcoma.
Etiology of Canine Osteosarcoma
What causes osteosarcoma, both in humans and dogs? Nobody is exactly sure, though many have speculated about possible mechanisms. Some have hypothesized cell damage due to ionizing radiation or carcinogenic chemicals as a possible causes. Nutritional factors have been studied, since the tumor usually develops near the region of the long bones where growth takes place (the growth plates). Other possibilities include trauma to the bones, and damage resulting from implants. Studies have been conducted to determine whether hormonal factors may be at play, perhaps in connection with neutering of the dogs. Genetic predisposition is another possibility; the presence of abnormal copies of a gene known as p53, which normally inhibits tumor development, correlates with increased osteosarcoma incidence.
Presentation and Diagnosis of Canine Osteosarcoma
Osteosarcoma in dogs typically presents as swelling, not always with pain initially, though pain will develop at some point. The dog is lame in the affected leg. The leg may fracture. On account of the pain, the dog will lose his or her appetite and lose weight, become lethargic, and often develop insomnia and be generally irritable. Unfortunately, by the time these symptoms appear, the tumor already has destroyed much of the bone in which it began. Even worse, in more than 90 percent of cases, the tumor already has metastasized to other bones and to the lungs.
X-rays can reveal visual features that are typical of an osteosarcoma in a bone. Together with clinical signs, usually this is enough to confirm a diagnosis. If needed though, a biopsy can be taken. In biopsy. a sample of the tumor is removed surgically, then examined by a pathologist.
Treatments for Canine Osteosarcoma
If osteosarcoma is detected early, there are treatments that not only can extend a dog’s life but can reduce the dog’s suffering. The treatments include surgery and chemotherapy, which usually means that the limb is amputated, followed by chemotherapy. If the cancer is in an early stage, amputation can actually save the dog’s life by preventing it from metastasizing to other parts of the body. Approximately 60 percent of dogs treated with amputation and chemotherapy for osteosarcoma are alive one year later, and forty percent two years later. In unusual cases in which only a tiny, isolated part of a bone is affected, it is possible to remove the tumor without amputation. Radiation treatment is used only to shrink an osteosarcoma in cases when it is so big that surgery is not possible.
Authorship of the Hebrew Bible
Although, traditionally, authorship of the Torah, is ascribed to Moses, and the various books of the prophets (Nevi’im) to the prophets themselves or in some cases to scribes working directly with them, the Genesis-Kings core of the Hebrew Bible does not actually make a point as to who wrote its parts. Even Deuteronomy, which is framed in the Torah as a recounting of Moses’ own words, is presented from the perspective of a narrator writing prose around poetic speeches attributed to Moses. As numerous people have observed throughout the centuries, Deuteronomy even describes Moses’ death and speaks of him as the humblest man who ever lived. This is not something that the humblest man who ever lived would have written about himself.
Many centuries prior to the emergence of the Documentary Hypothesis, Jewish scholars had observed this conflict with the assumption that Moses’ had written the Torah. Thus, in medieval Spain, Ibn Ezra advised those who “understood” to “remain silent”.
Richard Ellior Friedman’s books, particularly Who Wrote the Bible?, but also The Hidden Book on the Bible, are works of source criticism, but are fairly weak on historical criticism. Thus, while Friedman puts a lot of effort into which groups likely authored which source texts, his conclusions regarding the periods are based on relatively superficial analysis, assumptions that the united monarchy was completely historical, and ends of with a fairly wide window as to the time period for J and E (though he suggests that he began some research that would have narrowed the writing of E to the last 25 years of the of the kingdom of Samaria).
Furthermore, other scholars in Friedman's cohort don't agree with him on the dates. Baruch Halpern, who like Friedman did his doctoral work at Harvard under Frank Moore Cross in the 1970s, places the P author around 600 BCE. Additionally, using the evolution of the tribal structure of the branches of Judah as well as linguistic arguments, Halpern suggests that the CH had to proceed J by a century or so. Of course, this implies that Friedman cannot be right that J and the CH were the same man or woman, as he posits in The Hidden Book in the Bible.
Focusing on the intriguing possibility that Judahite palace women may played an important role in transcribing many oral traditions to written documents, Axel Knauf hypothesizes a court history evolving in stages with stories being told and rehashed under the guidance of the Queen-mothers Bathsheba, Maacah, and perhaps most importantly, Athalia, daughter of Ahab. While many scholars take at face value the contention by editors at least one point in the evolution of Kings that Athalia was an unpopular queen, Knauf essentially makes her a key figure in the creation of the official memory of David’s reign.
Many centuries prior to the emergence of the Documentary Hypothesis, Jewish scholars had observed this conflict with the assumption that Moses’ had written the Torah. Thus, in medieval Spain, Ibn Ezra advised those who “understood” to “remain silent”.
Richard Ellior Friedman’s books, particularly Who Wrote the Bible?, but also The Hidden Book on the Bible, are works of source criticism, but are fairly weak on historical criticism. Thus, while Friedman puts a lot of effort into which groups likely authored which source texts, his conclusions regarding the periods are based on relatively superficial analysis, assumptions that the united monarchy was completely historical, and ends of with a fairly wide window as to the time period for J and E (though he suggests that he began some research that would have narrowed the writing of E to the last 25 years of the of the kingdom of Samaria).
Furthermore, other scholars in Friedman's cohort don't agree with him on the dates. Baruch Halpern, who like Friedman did his doctoral work at Harvard under Frank Moore Cross in the 1970s, places the P author around 600 BCE. Additionally, using the evolution of the tribal structure of the branches of Judah as well as linguistic arguments, Halpern suggests that the CH had to proceed J by a century or so. Of course, this implies that Friedman cannot be right that J and the CH were the same man or woman, as he posits in The Hidden Book in the Bible.
Focusing on the intriguing possibility that Judahite palace women may played an important role in transcribing many oral traditions to written documents, Axel Knauf hypothesizes a court history evolving in stages with stories being told and rehashed under the guidance of the Queen-mothers Bathsheba, Maacah, and perhaps most importantly, Athalia, daughter of Ahab. While many scholars take at face value the contention by editors at least one point in the evolution of Kings that Athalia was an unpopular queen, Knauf essentially makes her a key figure in the creation of the official memory of David’s reign.
Injured Calf Muscle: How the Muscle is Injured, Prevention and Treatment
The calf muscle muscle is the common name for the triceps surae muscles of the leg. These can be torn, detached, or or partly detected from the tendons that hold them to bones when the foot bent suddenly and with extensive force. The triceps surae actually comprises a pair of muscles whose role is to flex the foot. The two muscles are soleus and the gastrocnemius, both of which insert into the calcaneus bone (the bone of the heal) by way of the Achilles tendon. The Achilles tendon is named for Achilles, the Greek hero of Homeric fame.
Flexion is defined as the position that the foot takes when the toes are pointed. The opposite movement is called extension, which stretches the calf muscles and the Achilles tendon as well. Often, the meanings of flexion and extension of the foot are reversed in common language, particularly in the case of dancers. However, in medicine and anatomy this is not correct. To avoid confusion, flexion often is called plantarflexion, while extension is known as dorsiflexion. Thus, it is a fast or powerful extension, or dorsiflexion, of the foot which pulls the calf muscles to the point of causing injury.
Calf muscle injury can happen during sporting events. If a foot is dorsiflexed suddenly, such as might happen in landing an under-rotated back somersault on a very hard surface, the Achilles tendon is pulled. If the tendon itself is not damaged but the muscle rips away, the liberated parts of the muscle may curl up. This is known as muscle rupture, or collapse. Symptoms of this condition include pain in the back of the calf, pain when the foot is plantarflexed against resistance (somebody holding the foot to make plantarflexion more difficult), and severed tightness of the calf for several days.
The risk of injuring the triceps surae can be reduced by doing a good warmup prior to exercising, with stretches that include the triceps surae and other muscle groups of the lower extremities.
If you believe that you may have injured your triceps surae, you should consult with your physician, athletic trainer, or with somebody with expertise in sports medicine. Initial treatment should begin with what is known in sports medicine by the acronym RICE -rest, ice, compression, elevation. Sit or lie down and have somebody bring you ice or a cold pack and apply it to the injured muscle for at least fifteen minutes. This will help to reduce swelling. Swelling can be reduced further with the application of a compression bandage. This is a stretchy bandage that wraps around around the leg. Wrap it tightly enough to feel snug, but not so tight that cuts off circulation. Elevating the leg, slightly above the ground, also will help to reduce the swelling. Finally, it is very important to rest the muscle. Do this by avoiding activity that is physically stressful.
Flexion is defined as the position that the foot takes when the toes are pointed. The opposite movement is called extension, which stretches the calf muscles and the Achilles tendon as well. Often, the meanings of flexion and extension of the foot are reversed in common language, particularly in the case of dancers. However, in medicine and anatomy this is not correct. To avoid confusion, flexion often is called plantarflexion, while extension is known as dorsiflexion. Thus, it is a fast or powerful extension, or dorsiflexion, of the foot which pulls the calf muscles to the point of causing injury.
Calf muscle injury can happen during sporting events. If a foot is dorsiflexed suddenly, such as might happen in landing an under-rotated back somersault on a very hard surface, the Achilles tendon is pulled. If the tendon itself is not damaged but the muscle rips away, the liberated parts of the muscle may curl up. This is known as muscle rupture, or collapse. Symptoms of this condition include pain in the back of the calf, pain when the foot is plantarflexed against resistance (somebody holding the foot to make plantarflexion more difficult), and severed tightness of the calf for several days.
The risk of injuring the triceps surae can be reduced by doing a good warmup prior to exercising, with stretches that include the triceps surae and other muscle groups of the lower extremities.
If you believe that you may have injured your triceps surae, you should consult with your physician, athletic trainer, or with somebody with expertise in sports medicine. Initial treatment should begin with what is known in sports medicine by the acronym RICE -rest, ice, compression, elevation. Sit or lie down and have somebody bring you ice or a cold pack and apply it to the injured muscle for at least fifteen minutes. This will help to reduce swelling. Swelling can be reduced further with the application of a compression bandage. This is a stretchy bandage that wraps around around the leg. Wrap it tightly enough to feel snug, but not so tight that cuts off circulation. Elevating the leg, slightly above the ground, also will help to reduce the swelling. Finally, it is very important to rest the muscle. Do this by avoiding activity that is physically stressful.
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