An end to needle phobia: Device could make painless injections possible

"As many as 1 in 10 people experience needle phobia, which may have negative consequences, such as decreasing the rate of vaccinations and blood donation," said William McKay, M.D., lead author of the study. Credit: © uwimages / Fotolia

Imagine no tears during infant vaccines and no fear of the needle for those old enough to know what's coming. Such painless injections could be possible with a device that applies pressure and vibration while the needle is inserted in the skin, according to a study presented at the ANESTHESIOLOGY™ 2014 annual meeting.

"As many as 1 in 10 people experience needle phobia, which may have negative consequences, such as decreasing the rate of vaccinations and blood donation," said William McKay, M.D., lead author of the study and a professor of anesthesiology in perioperative medicine and pain management at the University of Saskatchewan, Saskatoon, Canada. 

"Our early research suggests that using a device that applies pressure and vibration before the needle stick could help significantly decrease painful sensations by closing the 'gate' that sends pain signals to the brain."

Researchers studied the use of pressure, vibration, and cooling or warming in 21 adults poked in the shoulder by a plastic needle that doesn't break the skin but produces needle-like pain. They tested different levels of pressure, vibration and temperature to determine the amount that provided the most benefit. The perception of pain was significantly decreased when a specific amount of pressure and vibration was applied to the site for 20 seconds prior to using the plastic needle. The addition of heat added a small benefit, but it wasn't significant. The study should be repeated in children, who may experience pain differently, said Dr. McKay. The addition of heat or cold might be more beneficial, he said.

While commercial devices that include some of these features are available, they could be improved by incorporating the additional features tested in this and other studies, he said. They could be used to prevent pain prior to providing intravenous (I.V.) treatment, the drawing or donating of blood, or administering vaccinations.

The concept likely works by distraction as well as employing the gate-control theory of pain, in which these sensations (pressure, vibration and potentially temperature) close the gate that allows the brain to register pain.

Source: American Society of Anesthesiologists (ASA)

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Back pain killing your sex life? Study reveals best positions to save your spine

Contrary to popular belief, spooning is not always the best sex position for those with a bad back, according to new research from the University of Waterloo. For the first time ever, scientists have successfully documented the way the spine moves during sex and discovered exactly why certain positions are better than others when it comes to avoiding back pain. The pioneering study combined infrared and electromagnetic motion capture systems to track how ten couples' spines moved when attempting five common sex positions. The findings were used to create an atlas, or set of guidelines, that recommends different sex positions and thrusting techniques based on what movements trigger a patient's pain. Pictured: Professor Stuart McGill demonstrates the motion of the spine during sex.  
Credit: University of Waterloo

Contrary to popular belief, spooning is not always the best sex position for those with a bad back, according to new research from the University of Waterloo.

For the first time ever, scientists have successfully documented the way the spine moves during sex and discovered exactly why certain positions are better than others when it comes to avoiding back pain.

"Any family doctor will tell you that couples often ask them how to manage their back pain during and after sex. Many couples will remain celibate because one night of love-making can lead to months of back agony," said Professor Stuart McGill, of Waterloo's Faculty of Applied Health Sciences. "Until now, doctors have never had any hard science to base their recommendations upon."

The pioneering study combined infrared and electromagnetic motion capture systems -- like those used in the creation of video games -- to track how 10 couples' spines moved when attempting five common sex positions. The findings were used to create an atlas, or set of guidelines, that recommends different sex positions and thrusting techniques based on what movements trigger a patient's pain.

"Before now, spooning was often recommended by physicians as the one position that fit all. But as we've discovered, that is not the case," said Natalie Sidorkewicz, a PhD candidate at Waterloo and lead author on the paper. "Sex positions that are suitable for one type of back pain aren't appropriate for another kind of pain."

The atlas recommends that men who are flexion-intolerant -- meaning those whose back pain is made worse by touching their toes or sitting for long periods of time, for example -- replace spooning with doggy-style sex. The guide recommends that these men use a hip-hinging motion rather than thrusting with their spines.

"For the first time ever, we now have very solid science to guide clinicians on their recommendations for patients who suffer debilitating back pain, but still want to be intimate," said Sidorkewicz. "This has the potential to improve quality of life -- and love-life -- for many couples."

According to Statistics Canada, four of every five people will experience at least one episode of disabling low back pain in their lifetime. Up to 84 per cent of men with low back pain and 73 per cent of women report a significant decrease in the frequency of intercourse when suffering back pain.

The study also shed light for the first time on the mechanics of the male orgasm. Electrodes hooked up to the male participants' muscles revealed that it is abdominal and buttock, not back muscles, that are most active during orgasm. Spine motion, on the other hand, varied with the individual. For some males, a drastic increase in flexion or extension was seen, while for others spine motion did not change much at all.

"Many of the back pain patients that we see have told us that they experience elevated levels of pain during orgasm, to the point where they will avoid having one during sex with their partner," said Sidorkewicz. "These initial findings help us to begin to understand what might be provoking their pain during the moment of climax."

A paper documenting male spine movement was published in the journal Spine. Female findings are expected to be published in the coming months. The next phase of the study will involve recruiting patients with hip pain and additional categories of back pain to further develop the guidelines.

Source: University of Waterloo

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New technology may identify tiny strains in body tissues before injuries occur

The top image shows how the new algorithm is able to identify an area (in red) where stress has created a weak spot in a small piece of plastic wrap. The older method (shown in the bottom half of the picture) is unable to pinpoint the place where the plastic wrap is weakening.
Credit: John Boyle, © The Royal Society (used with permission)

Researchers at Washington University in St. Louis have developed algorithms to identify weak spots in tendons, muscles and bones prone to tearing or breaking. The technology, which needs to be refined before it is used in patients, one day may help pinpoint minor strains and tiny injuries in the body's tissues long before bigger problems occur.

The research is available online Aug. 27 in the Journal of the Royal Society Interface, which publishes research at the nexus of the physical and life sciences.

"Tendons are constantly stretching as muscles pull on them, and bones also bend or compress as we carry out everyday activities," said senior investigator Stavros Thomopoulos, PhD, professor of orthopaedic surgery. "Small cracks or tears can result from these loads and lead to major injuries. Understanding how these tears and cracks develop over time therefore is important for diagnosing and tracking injuries."

To that end, Thomopoulos and his colleagues developed a way to visualize and even predict spots where tissues are weakened. To accomplish this, they stretched tissues and tracked what happened as their shapes changed or became distorted.

The paper's first author, John J. Boyle, a graduate student in biomedical engineering, combined mechanical engineering fundamentals with image-analysis techniques to create the algorithms, which were tested in different materials and in animal models.

"If you imagine stretching Silly Putty or a swimming cap with a picture on it, as you pull, the picture becomes distorted," Boyle said. "This allows us to track how the material responds to an external force."

In one of the experiments described in the paper, Boyle sprayed a pattern of dots on plastic wrap, stretched it and tracked the dots.

"As you pull and stretch the plastic wrap, eventually tears begin to emerge," he explained. 

"The new algorithm allowed us to find the places where the tears were beginning to form and to track them as they extended. Older algorithms are not as good at finding and tracking localized strains as the material stretches."

In fact, one of the two new algorithms is 1,000 times more accurate than older methods at quantifying very large stretches near tiny cracks and tears, the research showed. And a second algorithm has the ability to predict where cracks and failures are likely to form.

"This extra accuracy is critical for quantifying large strains," said Guy Genin, PhD, professor of mechanical engineering and co-senior investigator on the study. "Commercial algorithms that estimate strain often are much less sensitive, and they are prone to detecting noise that can arise from the algorithm itself rather than from the material being examined. The new algorithms can distinguish the noise from true regions of large strains."

Thomopoulos, who also is a professor of biomedical engineering and of mechanical engineering, works with Genin to study the shoulder's rotator cuff, a group of tendons and muscles that connect the upper arm to the shoulder blade. They want to learn why some surgeries to repair rotator cuff injuries ultimately fail. Their goal is to increase the odds that the tissue in the shoulder will heal following surgery, and they believe the new algorithms could help them get closer to that goal.

How soon the new algorithms could be used in patients depends on getting better images of the body's tissues. Current imaging techniques, such as MRI and ultrasound, lack the required clarity and resolution.

Genin also explained that although the goal of the current study is to better understand how forces at work on human tissue cause injury and stress, the algorithms also could help engineers identify vulnerable parts of buildings and other structures. Our muscles and bones, he said, are influenced by the same strains that affect those structures.

"Whether it's a bridge or a tendon, it's vital to understand the ways that physical forces cause structures and tissues to deform so that we can identify the onset of failures and eventually predict them," he said.

In the long run, they want to use the algorithms to prevent additional injuries following surgery to repair knees, shoulders and other tissues. They also said it may be possible some day to predict problems before they occur.

The group, which applied for a provisional patent earlier this year, hopes the algorithms will be useful to researchers in the medical and engineering fields.

As a piece of plastic wrap is stretched, the new algorithms identify the location (in red) where it is weakening, which is where the material eventually breaks.

Source: Washington University in St. Louis

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Neck manipulation may be associated with stroke

Vertebral artery as it passes through the neck vertebrae of the spine and enters the skull base. Arrows indicate head movement during lateral rotation and lateral flexion, motions that may be performed as part of a neck manipulation. Credit: © 2013 Trial FX.

Manipulating the neck has been associated with cervical dissection, a type of arterial tear that can lead to stroke. Although a direct cause-and-effect link has not been established between neck manipulation and the risk of stroke, healthcare providers should inform patients of the association before they undergo neck manipulation.

Treatments involving neck manipulation may be associated with stroke, though it cannot be said with certainty that neck manipulation causes strokes, according to a new scientific statement published in the American Heart Association's journal Stroke.

Cervical artery dissection (CD) is a small tear in the layers of artery walls in the neck. It can result in ischemic stroke if a blood clot forms after a trivial or major trauma in the neck and later causes blockage of a blood vessel in the brain. Cervical artery dissection is an important cause of stroke in young and middle-aged adults.

"Most dissections involve some trauma, stretch or mechanical stress," said José Biller, M.D., lead statement author and professor and chair of neurology at the Loyola University Chicago Stritch School of Medicine. "Sudden movements that can hyperextend or rotate the neck -- such as whiplash, certain sports movements, or even violent coughing or vomiting -- can result in CD, even if they are deemed inconsequential by the patient."

Although techniques for cervical manipulative therapy vary, some maneuvers used as therapy by health practitioners also extend and rotate the neck and sometimes involve a forceful thrust.

There are four arteries that supply blood to the brain: the two carotid arteries on each side of the neck, and the two vertebral arteries on the back of the neck. The influence of neck manipulation seems more important in vertebral artery dissection than in internal carotid artery dissection.

"Although a cause-and-effect relationship between these therapies and CD has not been established and the risk is probably low, CD can result in serious neurological injury," Biller said. "Patients should be informed of this association before undergoing neck manipulation."

The association between cervical artery dissection and cervical manipulative therapies was identified in case control studies, which aren't designed to prove cause and effect. An association means that there appears to be a relationship between two things, i.e., manipulative therapy of the neck and a greater incidence of cervical dissection/stroke. 

However, it's not clear whether other factors could account for the apparent relationship.

The relationship between neck manipulation and cervical artery dissection is difficult to evaluate because patients who already are beginning to have a cervical artery dissection may seek treatment to relieve neck pain, a common symptom of cervical artery dissection that can precede symptoms of stroke by several days.

You should seek emergency medical evaluation if you develop neurological symptoms after neck manipulation or trauma, such as:

• Pain in the back of your neck or in your head;
• Dizziness/vertigo;
• Double vision;
• Unsteadiness when walking;
• Slurred speech;
• Nausea and vomiting;
• Jerky eye movements.

"Tell the physician if you have recently had a neck trauma or neck manipulation," Biller said. 

"Some symptoms, such as dizziness or vertigo, are very common and can be due to minor conditions rather than stroke, but giving the information about recent neck manipulation can raise a red flag that you may have a CD rather than a less serious problem, particularly in the presence of neck pain."

Source: American Heart Association

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Correct seat belt use saves children's lives

Nine out of ten children are seriously or fatally injured in traffic accidents because they are incorrectly restrained or because of loose objects in cars. Credit: Marianne Skjerven-Martinsen, NIPH

Nine out of ten children are seriously or fatally injured in traffic accidents because they are incorrectly restrained or because of loose objects in cars. Correct use of safety equipment will save more lives, according to a new study from the Norwegian Institute of Public Health (NIPH).

Why are some children seriously or fatally injured in traffic accidents while other children in the same vehicle walk away without physical injury? This is one of the main questions Dr Marianne Skjerven-Martinsen at the NIPH studied as part of her doctoral dissertation.

The study is part of the research project 'Barn i bil' (Eng: Children in cars), a collaboration between the NIPH and Oslo University Hospital. As part of the project, a roadside study of normal traffic on Norwegian high-speed roads also took place which showed that every third child was incorrectly restrained.

Correct seat belt use is crucial

By investigating traffic accidents in Norway, Skjerven-Martinsen and her colleagues documented that incorrect restraint and loose objects in cars play a significant role in the number of deaths and injuries among children.

The results show that:

• Accidents where children are seriously injured mainly occur on high speed roads, in weekend traffic and most often follow frontal collisions on roads without crash barriers between carriageways.
• More than 9 out of 10 children who were seriously or fatally injured in traffic accidents were incorrectly restrained or were hit by loose objects in the car.
• The most common error is that the seatbelt is misplaced, with the shoulder belt under the arm or behind the back, or the lap belt is placed too high on the abdomen.
• Loose objects also cause damage to passengers, often indirectly when heavy luggage shifts, displacing the rear seat where the child is sitting.
• Correctly secured children have a low risk of injury, even in a heavy collision.

Children over 4 years are injured most frequently and the most common injuries are to the head, face, chest and abdomen.

For younger children, the most common errors are loose or misplaced straps.

Learn from experience

"We see that adults want to protect their children but they may lack knowledge of what can happen if the equipment is not used properly. The aim of this study was to evaluate the incorrect usage of child restraint in the vehicle, related to the child's height, age and type of equipment. In this way, we can give advice to parents, authorities and particularly the motor industry," says Skjerven-Martinsen.

In her thesis, she also described how children of different ages should be secured to prevent serious injury in car accidents. The findings provide a scientific basis for targeted prevention.

Source: Norwegian Institute of Public Health

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