Thyroid and Parathyroid Dysfunctions and the Musculoskeletal System

The thyroid and parathyroid glands are critical endocrine organs responsible for regulating a myriad of physiological processes, including those within the musculoskeletal system. The thyroid gland synthesises thyroid hormones, which are essential for normal bone and muscle development and function. Conversely, the parathyroid glands secrete parathyroid hormone (PTH), a pivotal regulator of calcium levels in the bloodstream. Dysfunctions of these glands can significantly affect the musculoskeletal system, leading to a range of symptoms and complications.

Thyroid Dysfunction and Musculoskeletal Health

Hypothyroidism:

Hypothyroidism, characterised by inadequate thyroid hormone production, is the most common thyroid disorder, affecting approximately 1-2% of the population. This condition can have a profound impact on the musculoskeletal system, resulting in various symptoms and complications:

  • Muscle Weakness and Fatigue: Individuals with hypothyroidism often experience muscle weakness and debilitating fatigue, hampering their daily activities.
  • Myalgia and Arthralgia: Hypothyroidism is associated with myalgia (muscle pain) and arthralgia (joint pain), further limiting mobility and causing discomfort.
  • Carpal Tunnel Syndrome: Hypothyroidism elevates the risk of developing carpal tunnel syndrome, characterised by numbness, tingling, and weakness in the hands, affecting fine motor skills.
  • Myositis and Osteoporosis: Myositis, marked by inflammation of the muscles, is another musculoskeletal manifestation of hypothyroidism. Additionally, individuals with hypothyroidism face an increased risk of osteoporosis, a condition typified by brittle bones and heightened susceptibility to fractures.
  • Adhesive Capsulitis (Frozen Shoulder): Emerging studies have unveiled a link between hypothyroidism and an augmented risk of adhesive capsulitis, commonly known as frozen shoulder. Adhesive capsulitis entails inflammation and thickening of the shoulder joint capsule, leading to a gradual loss of both active and passive shoulder mobility.

The exact mechanisms underlying how hypothyroidism affects the musculoskeletal system, including the development of adhesive capsulitis, remain incompletely understood. Nevertheless, it is postulated that thyroid hormones play crucial roles in muscle metabolism, bone turnover, and nerve function.

Hyperthyroidism:

Hyperthyroidism, characterised by excessive thyroid hormone production, is less common than hypothyroidism, affecting approximately 1% of the population. Despite its lower prevalence, hyperthyroidism can also impact the musculoskeletal system, leading to symptoms such as:

  • Muscle Weakness and Atrophy: Hyperthyroidism accelerates muscle metabolism and bone turnover, culminating in muscle weakness and atrophy.
  • Osteoporosis and Fractures: The influence of hyperthyroidism on bone turnover contributes to the development of osteoporosis and heightens the risk of fractures.

Parathyroid Dysfunction and Musculoskeletal Health

Hypoparathyroidism:

Hypoparathyroidism occurs when the parathyroid glands fail to produce sufficient PTH. This condition can result from various factors, including surgery, autoimmune disease, and genetic disorders, leading to musculoskeletal symptoms like:

  • Muscle Cramps and Tetany: Reduced PTH levels lead to low blood calcium levels, precipitating muscle cramps and tetany (muscle spasms).
  • Osteomalacia and Fractures: Hypoparathyroidism impairs bone mineralization, resulting in osteomalacia (softening of the bones) and an elevated risk of fractures.

Hyperparathyroidism:

Hyperparathyroidism is characterised by excessive PTH production, which can be caused by factors such as tumours, overgrowth of the parathyroid glands, and genetic disorders. This condition can affect the musculoskeletal system in the following ways:

  • Muscle Weakness: Elevated PTH levels can damage muscles, leading to muscle weakness.
  • Bone Pain: Individuals with hyperparathyroidism may experience bone pain due to high blood calcium levels.
  • Osteoporosis and Fractures: Chronic hyperparathyroidism can result in osteoporosis and an increased susceptibility to fractures.

Treatment

Treatment for thyroid and parathyroid dysfunctions aims to restore normal hormone levels and address resulting imbalances:

  • Hypothyroidism: Treatment involves thyroid hormone replacement medication to elevate thyroid hormone levels to normal.
  • Hyperthyroidism: Management options encompass medication to counteract the effects of thyroid hormones, radioactive iodine therapy to obliterate thyroid tissue, or surgery to remove part or all of the thyroid gland.
  • Hypoparathyroidism: Patients with hypoparathyroidism frequently require calcium and vitamin D supplements to maintain adequate calcium levels in the bloodstream.
  • Hyperparathyroidism: Treatment typically entails surgical removal of the affected parathyroid gland(s) to restore normal PTH levels.

Conclusion

Thyroid and parathyroid dysfunctions wield a profound influence on the musculoskeletal system, eliciting a spectrum of symptoms and complications, including adhesive capsulitis. Recognising the potential musculoskeletal repercussions of these disorders is imperative for early diagnosis and prompt intervention. Timely treatment can mitigate the risk of severe complications, such as osteoporosis, fractures, and frozen shoulder (adhesive capsulitis), enabling individuals to preserve their musculoskeletal health and overall well-being.

The Great Debate: Stretching Before or After Exercise?

Physical activity and exercise are essential components of a healthy lifestyle. Whether you’re a seasoned athlete or just starting your fitness journey, the question of when to incorporate stretching into your routine has likely crossed your mind. Should you stretch before or after exercise? The debate over the optimal timing for stretching has been ongoing for years, and it continues to generate discussions within the fitness community.

The Role of Stretching

Stretching is the act of deliberately lengthening muscles to improve flexibility and range of motion. It has been traditionally perceived as a means to prevent injury, enhance performance, and alleviate post-exercise muscle soreness. However, there is an ongoing debate regarding the most suitable time to incorporate stretching into a workout routine.

Stretching Before Exercise

Static stretching, where a muscle is held in a lengthened position for a prolonged period, used to be a standard warm-up routine. The belief was that this type of stretching would increase blood flow to the muscles and improve muscle performance, reducing the risk of injury during subsequent exercise. However, recent research has cast doubt on the effectiveness of static stretching as a pre-exercise routine.

A study published in the “Journal of Strength and Conditioning Research” in 2019 examined the effects of static stretching before exercise on performance and injury risk. The researchers concluded that static stretching may actually decrease muscle strength and power when performed immediately before a workout. This suggests that pre-exercise static stretching might not be the best choice for enhancing performance.

Stretching After Exercise

Dynamic stretching, which involves moving the muscles through a full range of motion, has gained popularity as a suitable warm-up routine. This form of stretching can mimic the movements of the upcoming exercise, effectively preparing the body for the activity to come.

Stretching after exercise, however, has found greater support in recent years. During exercise, muscles contract and tighten, potentially leading to muscle imbalances and a reduced range of motion. Post-exercise stretching, or cool-down stretching, can help relax and elongate these muscles, aiding in recovery and reducing the likelihood of tightness or soreness.

A study published in the “Scandinavian Journal of Medicine & Science in Sports” in 2018 explored the effects of static stretching after exercise. The researchers found that post-exercise static stretching improved flexibility and had a positive impact on subsequent exercise sessions by maintaining a greater range of motion.

The Middle Ground: Incorporating Both

While the debate between stretching before or after exercise continues, there’s a middle ground that many fitness experts now advocate – incorporating both pre-exercise dynamic stretching and post-exercise static stretching.

Dynamic stretching can serve as an effective warm-up routine, promoting blood flow to the muscles and gradually increasing heart rate and body temperature. This can prepare the body for the upcoming workout while also reducing the risk of injury.

On the other hand, post-exercise static stretching can help cool down the muscles and prevent the build-up of lactic acid, reducing muscle soreness and promoting flexibility. Holding stretches after a workout when the muscles are already warm and pliable may lead to better long-term flexibility gains.

Conclusion

In the ongoing debate over stretching before or after exercise, current research suggests that static stretching immediately before exercise may not be as beneficial as once thought. Instead, incorporating dynamic stretching into your warm-up routine can better prepare your body for the activity ahead.

Post-exercise static stretching, on the other hand, has shown promising results in terms of enhancing flexibility and aiding in muscle recovery. Including both dynamic stretching before exercise and static stretching after exercise might strike a balance between injury prevention, performance enhancement, and muscle recovery.

It’s important to note that individual preferences and needs vary. Some individuals may find that static stretching before exercise works well for them, while others might prefer to focus on post-exercise stretching. Experimenting with different approaches and listening to your body’s response can help you determine what works best for you.

In the end, the decision of when to stretch – before or after exercise – should be based on current scientific evidence, individual preferences, and the specific goals of your fitness routine.

References

  1. Behm, D. G., & Chaouachi, A. (2011). A review of the acute effects of static and dynamic stretching on performance. European Journal of Applied Physiology, 111(11), 2633-2651.
  2. Kay, A. D., & Blazevich, A. J. (2012). Effect of acute static stretch on maximal muscle performance: A systematic review. Medicine & Science in Sports & Exercise, 44(1), 154-164.
  3. Simic, L., Sarabon, N., & Markovic, G. (2013). Does pre?exercise static stretching inhibit maximal muscular performance? A meta?analytical review. Scandinavian Journal of Medicine & Science in Sports, 23(2), 131-148.
  4. Kruse, N. T., Barr, M. W., & Gilders, R. M. (2019). Acute effects of static stretching on peak torque and mean power output in National Collegiate Athletic Association Division I women’s basketball athletes. Journal of Strength and Conditioning Research, 33(1), 165-172.
  5. Opplert, J., & Babault, N. (2018). Acute effects of dynamic stretching on muscle flexibility and performance: An analysis of the current literature. Sports Medicine, 48(2), 299-325.

Tender Tendons

Tendon problems can affect many areas of the body such as the elbows (tennis elbow and golfer’s elbow), hips, knees (runner’s knee), ankles (Achilles tendon) and feet (policeman’s heel). In the past these problems went by the name of tendonitis. The suffix “itis” was used because it was thought that inflammation was present. Imaging techniques like ultrasound and MRI scans have revealed that there is in fact very little inflammation (except possibly in the very early stages) but instead degenerative changes were found. This led to the replacement of tendonitis by tendinosis. The suffix “osis” means degeneration. Recently however, studies have found that the imaging findings are not directly related to symptoms:

  • some people are symptom-free even though they have structural tendon pathology
  • as symptoms improve, structural pathology doesn’t change
  • structural pathology is not necessarily a good predictor of recovery

This has led to a yet another word being used…tendinopathy. The “pathy” simple means problem…something is wrong but we’re not exactly sure what it is! It’s thought that past experience, emotion and adverse pain beliefs could lead to a hypersensitive nervous system.

That being said, it’s believed that tendon overload plays a crucial role, whereby the rate of wear is greater than the rate of repair. Therefore, inciting factors tend to fall under 2 categories.

1) Factors that increase the rate of tear:

  • repetitive impact activities
  • tendon compression
  • sudden increase in training volume, intensity or frequency
  • muscle weakness
  • faulty biomechanics
  • obesity

2) Factors that decrease the rate of repair:

  • menopause
  • age
  • rheumatoid arthritis
  • type II diabetes
  • high cholesterol
  • statins
  • smoking

After a thorough clinical assessment the probable causative factors should be addressed when possible. The aim of treatment is to decrease pain, promote healing and improve function. There are several different treatments that are used. The choice usually depends on the site, severity of symptoms and the stage of presentation. In the early stages when there is possibly some inflammation present, NSAIDs, rest, ice, wedges, taping or splinting can be used. Obviously, physiotherapy and acupuncture are useful and corticosteroid injections are helpful (especially when performed around the tendon rather than in it). Surgery is a last resort and results can sometimes be disappointing. Some of the best evidence is for the use of extracorporeal shock-wave therapy or a progressive exercise programme. In fact, a progressive exercise programme should be part of all treatment packages particularly alongside treatments that are successful at decreasing pain but that don’t improve healing or function. A graduated exercise programme can ensure the long-term success of treatment.

Nelson Mandela (1918-2013)

I have to admit shedding a few tears when I heard Nelson Mandela had passed away and it’s probably the first time I’ve done that for someone I didn’t personally know. I learnt about Mandela’s life through his recollection of it in his amazing autobiography ‘Long Walk to Freedom’. It’s incredible to believe that in his lifetime he went from being considered a second class citizen, unable to travel freely within his own country…to eventually being elected president of South Africa! What impresses me even more, is his character; after being imprisoned for close to 30 years he managed to emerge without any bitterness or resentment…and only through that attitude of forgiveness and reconciliation was it possible to unite a fractured nation. During the 1995 Rugby World Cup, he succeeded in getting the nation to support the Springboks by publicly wearing their jersey which had previously been considered a symbol of apartheid.

 

He was often cheerful and humorous and despite his monumental achievements remained humble until the end. I’m convinced his attitude to life had a big part to play in his longevity. A long and fruitful life to be cherished and celebrated.

May he rest in peace.

BBC Horizon’s – The Truth About Personality

Yet another great BBC Horizon production presented by Michael Moseley. This time Dr Moseley is on a quest to find out more about personality. In part fueled by a desire to cure 20 years of chronic insomnia and to find out whether he can change his self-confessed pessimistic outlook on life. As a qualified doctor and BBC presenter I guess his pessimism hasn’t served him too badly so far!

In the 70s, Oxford Ohio was the seat of an interesting social experiment. People over 50 years old were questioned and followed over several years to learn more about aging. Professor Becca Levy (Yale University) analysed the data and found that it was in fact attitude that determined longevity. People with positive beliefs about aging live an average of 7.5 years longer than those with negative beliefs. They put it into context by noting that curing cancer would only add 3-4 years life expectancy.

One of the most important personality traits is whether we’re optimistic or pessimistic. Being pessimistic, anxious and neurotic affects our reaction to the world but how can we objectively measure this? Well, it’s been found that these traits lead to an increased activity of the right frontal cortex compared to the left. To measure this, Dr Moseley visited Professor Elaine Fox (University of Essex). It turned out he had 3 times more activity on the right than the left. His pessimism was confirmed! In addition, Prof Fox had him take a test to check his reaction time to dots on a screen. The dots were either preceded by an angry face or a happy face. His reaction time was a lot shorter when the dots were preceded by an angry face. Possibly because he had a habit of focusing more on the negative than the positive.

At MIT Professor Rosalind Picard asked him to wear a wristband whilst they had a chat. The wristband measured his skin temperature and electrical conductivity which are both affected by the autonomic nervous system and so gave a good indication of his emotional state. Dr Moseley’s baseline levels were high, suggesting heightened arousal, even though he felt relaxed. That’s because intriguingly, the body tells us about a change in state before the mind realises.

So now he had evidence indicating he was pessimistic and possibly a little anxious. What could he do about it? Professor Fox suggested using Cognitive Bias Modification (CBM). He simply had to look at screen shots of mainly unhappy faces and spot the one happy face…repeatedly. In theory this decreases the unconscious negative bias by breaking the habit of looking for the negative. Evidence has shown that it helps combat anxiety but not depression. Dr Moseley confided in being self- absorbed, worrying about the past, stressing about the future and as a result being unable to savour the present. So he decided to use CBM 3x/week for about 7 weeks.

His next encounter was with Andy Puddicombe, a former Buddhist monk, who now teaches mindfulness meditation. He said that 10-20 mins of meditation a day would be enough to make a psychological and physiological difference. MRI studies of meditators have shown they have increased grey matter in areas that regulate emotion and increased activity in the left prefrontal cortex which is a centre for positive emotions. The meditation he was taught consisted of focusing on breathing. With training, the mind wanders less down negative habitual routes. So in addition to his CBM training, Dr Moseley decided to do 7 weeks of daily mindfulness meditation.

How does our personality come about? Is it nature or nurture? Professor Tim Spector (King’s College London) has studied identical twins for over 20 years. He believes that 40-50% of personality is based on genetics. His study of discordant twins has revealed that genes can change through life! This is the fascinating field of epigenetics. Genes can be switched on or off by stressful life events. If they can change in one direction they can change in the other, which means we can regain control of our genes!

Professor Michael Meaney’s (McGill University) studies on mice have demonstrated that the effect of good maternal care (more contact, licking) protects rats from anxiety by modifying genes and these changes are transmitted through generations. The hippocampus controls stress, emotion and memory. Better mothering increases glucocorticoid receptors in this part of the brain.

After 7 weeks of CBM and mindfulness meditation Dr Moseley confessed he was sleeping better than he had in the last 10 years! He repeated the tests and measurements with professor Fox and found that he now had less than 2 times more activity in the right frontal cortex than the left. The activity in the right frontal cortex was half of what it previously was. His reaction time was now better when preceded by a happy face than an angry face, which suggested he may be noticing more of the positive in his daily life.

 

The Perfect Human Diet

Last week I came across a documentary entitled “The Perfect Human Diet”. It was released last year and directed and produced by C J Hunt. Hunt had serious health problems from an early age and experimented extensively with diets. At the age of 46 he decided to travel the world in search of the perfect diet. His findings  support the Paleo diet. Those that are unfamiliar with it will find the documentary fascinating. Here is a summary.

We’re in the midst of an obesity and diet-related chronic disease epidemic. The US alone accounts for 300,000 to 400,000 deaths a year! There’s a lot of confusion related to diet, it’s complicated, the recommendations change and seem to be based more on beliefs than science.

The nutritional pioneer Weston Price studied native diets among tribal populations and found that they had better teeth and better facial bone structure than westerners. More recently, Kerin O’Dea from the University of Southern Australia conducted an experiment with a group of overweight Aboriginals living in cities. She sent them for seven weeks in the outback where they lived a hunter-gather lifestyle with a diet that was 50% to 60% animal based. They all lost weight and improved their health. Jay Wortman has studied Inuit populations and found that today a lot of them suffer from obesity, type II diabetes and metabolic syndrome. Traditionally they lived on low carbohydrate diets and so it’s hypothesised that the disease is linked to the modern high carbohydrate diets.

In 1863 a London undertaker named William Banting popularised a diet recommended to him by the famous physician Dr William Harvey. At the time Banting was 65 years old, overweight, had poor eyesight, poor hearing and joint pains. Two years later he had lost 50 pounds and regained his health. Dr Harvey had recommended that he stop eating bread, butter, sugar, potatoes and  stop drinking milk and beer. Instead he advised meat, fish, poultry, dried fruit, vegetables and wine.

From 1865 to 1965 the standard hospital treatment for obesity was to decrease carbohydrate intake. In the 1950s  the idea that fat causes heart disease, by it’s effect on cholesterol, began to spread. The fats were replaced by carbohydrates. They had suddenly become good! Today the US Diet Guidelines are to decrease portion size, decrease sugar, decrease salt, and decrease saturated fats.

Professor Loren Cordain is a leader in evolutionary diet and author of “The Paleo Diet”. In order to understand the Paleo Diet we need to go back in time…2 million years back in time! About 2 million years ago Homo Erectus appeared on the savannah of Africa. They were anatomically similar to us and evidence of hunting tools suggests that they consumed a lot of meat. This is backed up by recent analysis of Homo Erectus bone fragments. Their diet contained a huge diversity of food which differed from their predecessors’ diet which was mainly plant-based. The increased amounts of omega 3 fatty acids are thought to have been a precursor for brain growth and behavioural sophistication. Then, 230,000 years ago, Neanderthals appeared in Europe and 192,000 years ago modern humans appeared in Africa. They left Africa 75,000 years ago and entered Europe 45,000 years ago. Bone analysis suggests that the diet of Neanderthals and the first modern human was very similar to that of Homo Erectus.

Everything changed 10,000 years ago. Man decided to settle and use agriculture. Diets changed. Dairy and grains, like wheat, were included and the variety of food decreased. The period before 10,000 years ago is known as the Paleolithic era and the period after is known as the Neolithic era. In the 18th and 19th centuries the industrial revolution led to the refinement of sugars, grains and other foods. More recently processed foods have flooded the market and can constitute up to 70% of modern human diets.

The Paleo Diet theory is based on the fact that the Paleolithic era is much, much longer than the Neolithic era and it’s during the Paleolithic that modern humans evolved. Therefore, we have evolved to eat the diets of our Paleolithic ancestors which is why we struggle and have become unhealthy on modern diets. Voila!

Interesting though the documentary was, it didn’t give a full list of foods to eat and avoid, so I had a look on Wikipedia. The Paleo diets advocates: fish, meat (grass-fed), vegetables, fruit, fungi, roots and nuts. It suggests to avoid: grains, legumes, dairy, potatoes, refined salt, refined sugar and processed oils (Wikipedia).

Although the arguments in favour of the Paleo diet are compelling, I’m not entirely convinced. If obesity and ill-health are the result of the change in diet 10,000 years ago, how come obesity has only become more prevalent in the last 150 years (see “The Obesity Paradox“)? Are grains and dairy really that bad for us? In my opinion there are 2 influential factors that have driven the obesity and diet-related illness epidemic. Our physical activity has gradually decreased since the industrial revolution. Mechanisation and lately the widespread use of computers has meant that most of us spend our working days sitting and a lot of us spend our leisure time sitting as well. During the same period our diets have changed drastically and now include a lot more refined and processed foods. These convenience foods as they are also known are high in sugars, salts and saturated fats.

I agree that variety is key to a balanced diet and the Paleo diet does put forth a solid case for eating meat…or against vegetarianism and veganism. That said, we should bear in mind that the meat our Paleolithic ancestors ate is very different to the meat we eat today. Theirs came from wild, lean animals whereas today’s commercial meat comes from sedentary fattened stock!

The search for the perfect human diet continues…

 

 

 

Best Wishes For 2013!

May the New Year bring you health, wealth and happiness!

BBC Horizon’s – Eat, Fast And Live Longer

Another great programme from BBC Horizon presented by Dr Moseley. He starts off the programme by following the oldest man to complete the London marathon…a 101 yr old sikh who is healthy and takes no medication…the typical 65 yr old european takes 6 pills a day! The centenarian attributes his good health to his diet and more specifically his small portion size…about half of a normal adult”s.

This is not the first time that caloric restriction has been linked to longevity. In the 1930s, during the great depression in the US, although there were widespread food shortages…surprisingly life expectancy increased by 6 years. During the same period scientists at Cornell University found that animals on restricted diets lived longer.

Dr Moseley had a keen personal interest in the subject because of the threat of disease due to elevated blood sugar and cholesterol. He traveled the US speaking to the most eminent specialists in the field in a quest for a solution to his health problems. His first port of call was Professor Luigi Fontana from Washington University and Salerno Schools of Medicine. Prof Fontana advised a diet low in calories but high in nutrients and introduced Dr Moseley to Joe. Joe was in his 50s and had been on 1900 kcal/day for about 10 years. His body fat was 11.5% whereas Dr Moseley”s, also in his 50s, had a body fat % of about 27. Although the benefits were clear, Dr Moseley wanted to understand the mechanism in the hope of being able to draw the benefits without having to do any of the hard work! This is one of the reasons I like his programmes…his attitude is typical of the average european (or american)…we want results quickly, with as little effort as possible…sound familiar?

He then met up with Professor Valter Longo at the University of Southern California. Prof Longo showed him a special mouse…about half the size of a normal mouse…but incredibly it had a lifespan that was 40% longer…the equivalent of 120 human casino jameshallison years! The mouse had been genetically modified to have low levels of the a growth hormone called Insulin-like Growth Factor 1 (IGF1). IGF1 is thought to be the link between calorie restriction and longevity. There are about 350 people worldwide who have genetically inherited low levels of IGF1. Their condition is named Laron syndrome and although some of them smoke and eat what they want, amazingly they don”t get diabetes or cancer! Low levels of IGF1 seem to increase cell repair and decrease cell division (which probably accounts for their extremely small stature).

Protein has been found to increase our metabolism and put us in “go-go” mode but the downside is that it decreases cell repair. Three things can help decrease levels of IGF1: decreasing calorie intake, decreasing protein intake and lastly, the most effective way…is by fasting. Fasting can dramatically reduces levels of blood glucose and IGF1 within as little as 24 hrs. Obviously fasting can be dangerous and should only be undertaken if in good health and under close medical supervision. So Dr Moseley decided to give it a go for 3.5 days. He only allowed himself water, black tea and a 50 kcal soup each day. As expected, his blood sugar decreased significantly and his IGF1 levels halved. Unfortunately, the effects are only temporary and one would need to decrease protein intake and fast every couple of months to maintain changes…not for Dr Moseley, so he continued his search…

Dr Krista Varady from the University of Illinois at Chicago had a much more palatable proposition…eat as much of whatever you want on one day and eat a reduced amount of whatever you want the following day…feed day, fast day, feed day, fast day, etc. It”s called Alternate Day Fasting (ADF). On the fast days women are advised to eat 400-500 kcal and men 500-600 kcal. Preliminary trials with overweight subjects are showing promising results including weight loss, lower levels of bad cholesterol and fats in blood and decreased blood pressure.

Lastly, Dr Moseley paid a visit to Dr Mark Mattsen from the National Institute on Aging in Baltimore. He has conducted animal experiments on intermittent fasting and has found that it postpones the development of Alzheimer”s and senile dementia like diseases. Sporadic bouts of hunger seem to trigger the growth of new neurones! In evolutionary terms, this would have provided a survival advantage in times of famine. Intermittent fasting has better effects on the brain than daily calorie restriction. Dr Mattsen suggested alternating 5 days of normal eating with 2 days of fasting. So Dr Moseley gave it a go for 5 weeks. On the normal days her took in around 200 kcal and on the fast days he ate about 600 kcal. Please bear in mind that normal calorie intake is based on sex, height, weight and activity. The results were extremely impressive. He managed to lose 1 stone and decrease his body fat from 27% to 19%! His blood sugar levels decreased to within normal limits, his IGF1 levels halved, his total cholesterol decreased and his good cholesterol increased. I assume that although he could have eaten whatever he wanted, he was sensible about it.

Dr Moseley ended the programme by saying that it was “the most interesting journey that I”ve ever been on…and I”ve never said that before”.

 

Nerve Injuries

Nerves are cable-like structures that send information between the central nervous system (spinal cord and brain) and the target organs (internal organs, skin, muscles, joints, etc). A nerve if formed of bundles of axons surrounded by layers of connective tissue. Nerves are responsible for reflexes, sensation and muscle contractions. Pain, tingling, numbness and muscle weakness are tell-tale signs of nerve pathology.

The most common nerve injuries are:

  • Stretch-related injuries: these are encountered when traction forces exceed the nerve’s capacity to stretch eg. Erb’s Palsy is an injury to the brachial plexus during childbirth
  • Lacerations: these are caused by knifes, glass and other sharp implements
  • Compression injuries: these can either be caused by external forces, as in the “Saturday Night Palsy” or “Honeymooners Palsy”  which is a radial nerve compression generally preceded by arm pain to a degree that only excessive alcohol or love would drive a person to keep the arm in such an uncomfortable position; or internal forces eg. carpal tunnel syndrome and sciatica and it’s associated neurological symptoms. The latter is often referred to as a nerve entrapment or “trapped nerve”.

Seddon was the first to classify nerve injuries in 1943. His classification is probably the simplest and is still used today:

  • Mild injuries (Neurapraxia): temporary loss of conduction at injury site leading to sensory or motor problems; no damage to axon or surrounding sheath and connective tissue; full recovery within days or weeks.
  • Moderate injuries (Axonotmesis): temporary loss of conduction below the site of injury leading to sensory or motor problems; complete disruption of axon and surrounding myelin sheath below the level of injury but connective tissue encapsulations are preserved; because the tunnels formed by connective tissue are preserved, the sprouting axon shoots are able to eventually reconnect to the target organs; the process can take some time as nerves regenerate at a speed of about 1mm/day (0.5-9mm/day).
  • Severe injuries (Neurotmesis): temporary or permanent loss of conduction below the site of injury leading to severe sensory, motor and autonomic problems; partial or complete disruption of the entire nerve, including the connective tissue encapsulations; because of the discontinuity in the connective tissue tunnels and the formation of scar tissue, recovery without surgery is unlikely; also, after about a year of denervation, the sprouting axons are no longer able to connect to receptor sites on target organs such as muscle, sensory receptors may survive for many years.

In summary, and this may be obvious, nerve injuries that leave the connective tissue tunnels intact have a greater likelihood of leading to full recovery. Although it may take several months or even up to a year for this to happen. This type of injury usually results from compression injuries or mild stretch-related injuries. Severe stretch-related injuries and lacerations are more serious because they usually damage the connective tissue tunnels. This requires surgery and often leads to incomplete recovery.

Next week we’ll see how acupuncture can promote the regeneration of nerve injuries.

 

BBC Horizon’s Secret World Of Pain

Last year BBC Horizon created a documentary entitled ‘The Secret World of Pain‘. I watched it on YouTube a week ago, thought it was really well put together and so decided to share the most salient points.

Pain is one of our most ancient survival mechanisms and it protects and alerts us to danger. The SCN9A gene is responsible for regulating electrical signals that send pain sensation to the brain. Certain rare genetic disorders can prevent people from feeling pain…these unfortunate people are much more susceptible to burns and other injuries…this underlines just how crucial the sensation of pain is to us.

Pain can alert us to injury or potential injury, but why doesn’t it reflect the extent of injury…and why is it so subjective? There are a couple of possible reasons for this. Key experiences in early life have been found to be as important to pain perception as genetics. Early life is crucial for the formation of pain pathways which are shaped in response to touch. For example, premature babies are exposed to a lot more painful procedures and this alters the normal development of their pain pathways…the overdevelopment of pain pathways makes them hypersensitive and much more likely to experience pain in the future.

Pain and pleasure are both perceptions…psychological constructs…and so environment, context, decision-making, attention, distraction, motivation, emotion, etc can change how signals are processed and hence influence pain. There is a limit to how much information the brain can process at any one time…focussing attention on something pleasant (distraction) decreases the brain’s ability to process pain signals.

Subjects in an experiment were shown a triangle and exposed to a low temperature which they rated as 3/10 on a pain scale…this was repeated several times…they were then shown a square and exposed to a high temperature which they rated as 7/10 on a pain scale…this was repeated several times…they were then shown the square but exposed to the low temperature instead…surprisingly they rated the pain as 5/10. The researchers concluded that anxiety had affected their sensation of pain. I would add that expectation and conditioning may also have played a part.

Chronic pain is pain that persists long after an injury has healed…and therefore serves no purpose. It affects 1 in 5 people and is one of the biggest medical health problems. It can become an enormous burden on the brain and leads to chemical and structural changes. MRI scanning has revealed that people with chronic pain have less grey matter in the pre-frontal cortex. The answer to chronic pain may lie in reversing these changes. Encouragingly, electromagnetic impulses to the brain cortex have helped to normalise changes and to decrease pain, albeit temporarily. Research into this sort of treatment is extremely promising but still in its infancy.