Cyclist’s Palsy


Cyclist’s palsy, or sometimes called Handlebar palsy is a relatively common condition for road cyclists and mountain bikers. This palsy is a nerve injury at the wrist and until recently, has not been receiving much attention in the literature. First reported in European literature in 1896 by Destot, the condition got very little attention until it appeared in North American literature in 1975 by Eckman et al. Even then, the only published research were case reports which dealt strictly with findings in individual cases and no research was done to examine the exact mechanism or location of the nerve injury. More recent research has been designed to look closely at the Ulnar and even Median nerves at the wrist and look at the effect of cycling on nerve conduction. Below is a summary of the research done to this point in time.

The Ulnar nerve is a branch of the brachial plexus that provides sensation and motor supply to the upper extremity. The Ulnar nerve specifically is responsible for providing sensation and motor innervation to the medial (or inside) of the forearm and hand. The brachial plexus comes out at the neck, between muscles known as the scalenes, and then traverses the length of the arm before crossing the elbow after which it divides into its respective terminal branches. After passing the elbow, the ulnar nerve divides and gives off 2 sensory branches which supply sensation to parts of the back of the hand and the little finger and half of the ring finger. At the wrist, the ulnar nerve enters the hand by passing through Guyon’s Canal. This is a tight tunnel that is formed between 2 of the bones in your wrist (the pisiform and hamate bones) and the ligaments that join these bones together (pisohamate ligament). Either within or just beyond the canal, the ulnar nerve divides again in to two motor branches which supply some of the muscle in the hand and fingers. These branches are the branch to the hypothenar and the deep motor branch of the ulnar nerve. These innervate the muscles that help move the little finger and thumb respectively.



It is within Guyon’s Canal that the ulnar nerve is thought to get injured with cycling and depending on the exact point of injury, symptoms may vary from person to person. Since the sensory branches of the ulnar nerve are given off before or early into the canal, sensory loss is not found in all cases and is in fact a rare finding in cyclist’s palsy. The most common finding is that of weakness and clumsiness of the hand and thumb. Often people who develop this condition complain of numbness or tingling in the hand that goes away within a day or two but then they have persistent weakness with pinching and fine finger movements such as playing the piano.

The reason for the above symptoms is simple. While cycling, the position of the hands while holding the handlebars places pressure on the ulnar nerve in the canal. With either multi-day road cycling events or a single day of mountain biking, that pressure combined with vibrations from the road or trails is enough to damage the nerve and causes what is called a neuropraxia. A neuropraxia is a focal injury to a nerve that does not allow for conduction of a nerve impulse past the site of injury. The nerve functions normally both proximal and distal to the site of injury, and it is because of demyelination (loss of the protective nerve coating) at the site of injury that the nerve stops working and the muscles beyond that point get weak.

Ulnar Nerve at the Wrist

Guyon’s Canal


The good news about this type of nerve injury is that it is self–limiting, meaning that the nerve will regenerate on its own and function of the muscles will be restored. In a review by Capitani and Beer (2002), they found that within 3 months of the onset of symptoms and stopping the mechanism of injury, all motor function in the hand was restored to normal. It is important to know about this condition so that you can take steps to avoid it. A study by Akuthota et al found that long-distance bicycling caused a slowing of nerve impulses along the deep branch of the ulnar nerve in all of the cyclists in the study. They didn’t necessarily damage the nerve to the point of neuropraxia, but they did damage it enough to slow the conduction velocity. This shows how all long-distance cyclists are at risk of developing this condition. This same study also showed an exacerbation of Median nerve symptoms in a cyclist with carpal tunnel syndrome. This was due to wrist position on the handlebars. If your hands are on the handlebars in such a way that the wrist is held in extension, this can exacerbate carpal tunnel symptoms.

Tips to avoid placing too much stress on the hands and the Median and Ulnar nerves are:

• Wear padded gloves and/or ride with padded handlebars to minimize the vibration forces on your wrist and hands.
• Avoid direct pressure over the area of Guyon’s canal by avoiding resting the medial aspect of your wrist on the handlebars.
• Avoid letting your wrists rest in excessive extension.
• Make sure you have a proper seat height and sitting position. This will help minimize the amount of weight you place on your wrists.
• Select a proper choice of handlebar. The type of handlebar can also affect the amount of pressure you place through your wrists.
• More specifically for mountain biking, it is important to have good shocks on the front forks of your bike. They help to absorb and dampen the repetitive vibrations and impact on your wrist while on rough terrain.

To summarize, research has shown that long-distance bicycling slows the conduction time in the deep motor branch of the ulnar nerve which supplies the muscle in the thumb used for pinching and grasping. Research has also shown pre-existing nerve palsies, such as carpal tunnel syndrome, can be aggravated with long distance cycling. Furthermore, it has been found that cyclist’s palsy can be brought on by a single day of mountain biking. It is important to know the signs and symptoms of this condition so that it can be easily identified and a proper diagnosis established without having to go for numerous tests and possible surgery which can lead to lost days of work and loss of income. It is also very important to find a healthcare professional who can identify this condition and who knows how it is best treated. As previously mentioned, Capitani et al found that within three months, all or near all of the lost motor function was restored. Interestingly, Padua et al published a case of cyclist’s palsy that was treated by surgically releasing the ulnar nerve in Guyon’s canal. The patient was sent for surgery after the symptoms persisted for one month. It was reported that three months after surgery the patient recovered most of the motor function to the hand. Knowing the natural history of the cyclist’s palsy, one may be able to avoid unnecessary surgical intervention that will only serve to lengthen the recovery period. An accurate diagnosis is typically made by having a history of cycling, hand muscle weakness or clumsiness with no sensory loss. The diagnosis is confirmed with nerve conduction studies that show a decrease or loss of nerve conduction past guyon’s canal.


Key Concepts to Remember:

• Take preventative measures to decrease your risk of developing this condition, such as padded gloves, type of handlebar, shocks, etc.
• Have your seat height and position assessed by a professional to make sure it is customized to your height.
• If symptoms of hand weakness and/or clumsiness develop after a long ride, be sure to seek appropriate medical attention from someone familiar with this type of injury.
• If you develop symptoms, avoid cycling and other positions that place pressure over Guyon’s canal in order to give the nerve time to recover.
• Long-distance cycling can aggravate pre-existing palsies such as carpal tunnel syndrome.
  

References:

Akuthota V, Plastaras C, Lindberg K, Tobey J, Press J, Garvan C. The Effect of Long-Distance Bicycling on Ulnar and Median Nerves: An Electrophysiologic Evaluation of Cyclist Palsy. American Journal of Sports Medicine. 33 (8), 2005, pp 1224-1230.

Padua L, Insola A, LoMonaco M, Denaro FG, Padua R, Tonali P. A Case of Guyon Syndrome with Neuropraxic Block Resolved after Surgical Decompression. Electroendephalography and Clinical Neurophysiology. 109, 1998, pp. 191-193.

Capitani D, Beer S. Handlebar Palsy – acompression syndrome of the deep terminal (motor) branch of the ulnar nerve in biking. J Neurology. 249, 2002. pp. 1441-1445.

McIntosh KA, Preston DC, Logigian EL. Short-segment incremental studies to localize ulnar nerve entrapment at the wrist. American Academy of Neurology. 50 (1), 1998. pp. 303-306.

Can Creatine Supplementation Increase Athletic Performance?

Creatine supplmentation has been in the public eye since Linford Christie won the 100m gold medal at the 1992 Olympics games and I still keep hearing conflicting reports as to the effectiveness of its use in sports performance. In the following article I will try to summarize the research literature on creatine to hopefully clear up some of the issues surrounding its use.

What is Creatine?

Creatine is a naturally occuring nitrogenous organic acid in the human body and is essential for anaerobic muscular contractions. Simply put, creatine is stored in your muscles and is necessary for fast and powerful muscular contractions of short duration. Your body can naturaly regenerate creatine that gets used during anaerobic (short bursts) of exercise. The body can regenerate over half of the used creatine stores within 30 seconds after exercise and over 90% of used creatine after 5 minutes. However, when you use these creatine stores for repetitive exercise (such as lifting weights, sprinting, jumping) the body cannot regenerate all of the creatine in time and you start to get fatigued and are forced to stop. This is why you cannot sprint at the same intensity in the 100m as you would in the 400m or 800m! This is where creatine supplementation was designed to work.

How Does Creatine Supplementation Work?

By orally ingesting creatine, you can increase the amount of creatine stored in your body. It has been found that some people respond better to creatine supplementation then others and it is related to the amount already stored in the body. Think of it like a gas tank in your car, if the tank is full you can't add more fuel, however if the tank is only half full, you can top it up. Creatine is naturally found in red meats and those who eat a lot of red meat usually have higher levels of stored creatine and therefore do not always have as dramatic results by taking creatine supplements.

By topping off the creatine stores in your muscles, it has been found that you have a higher power output and it takes a longer time to fully fatigue the muscles. This can be beneficial during training for all power athletes (football, track and field, speed skating, weight-lifting...) who use this power system regularly.

Are There Different Kinds of Creatine Supplementation?

There are several different types of creatine available on the market. The most common are creatine monohydrate, creatine citrate, creatine phosphate and many brands include creatine in a sports drink powder. Of all of the above mentioned types of creatine, one type has been shown to help prolong fatigue better then others during high-intensity, short duration activity. Creatine Phosphate has been shown to help buffer the blood against the hydrogen ions (a waste product from anaerobic exercise that increase the blood acidity and gives you that muscle burning sensation). This increased buffering capacity allows for a longer time until total fatigue during continuous, maximum physical exertion. However, creatine phosphate was not compared to other forms of creatine to examine time to exhaustion with repetitive bursts of exercise, and may not show any increased benefits with that type of activity.

What to Expect?

• Most manufacturers of creatine suggest adding pure creatine powder to some form of sports drink to help with its absorption into the body.
• Many companies also suggest that you go on a 'loading phase' where you ingest 5g of creatine 3-6 times a day for the first 4-7 days. This helps increase the muscles' creatine stores more rapidly.
• Expect an initial weight gain when you start creatine supplementation because to store creatine in the muscle, it needs to be stored with water molecules. This will result in more water being stored in your body and thereby increases your body weight.
• With more water being stored in your body, you may become dehydrated, and it is important to ingest more water then usual thoughout the day.
• Finally, remember that not everyone has the same results after creatine supplementation. It depends largely on the amount already stored in your muscles and the type of exercise you do.

In Summary:

1. The oral ingestion of creatine supplementation can increase the amount of creatine stored in your muscles.
2. Mixing creatine powders with a sports drink helps increase the absorption rate into the body.
3. Dehydration is a common complaint so drink lots of water
4. Creatine supplmentation can improve anaerobic (short bursts at maximal capacity) performance.
5. Not all athletes respond the same to creatine supplementation

What is Medical Acupuncture?

Medical acupuncture is a modern treatment approach founded in concepts of neurology, anatomy and physiology. Similar to traditional Chinese acupuncture, medical acupuncture involves the strategic placement of sterile needles into various locations in the body. The major differences between the two forms of acupuncture is that medical acupuncture often uses a low frequency (2-8Hz) electrical stimulation on the needles, and the selection of acupuncture points is based both on the traditional Chinese approach as well as including points that are anatomically and neurologically connected to your specific source of pain. Medical acupuncture has been shown to have beneficial results by inducing muscle relaxation, modulating pain, altering your neuroendocrine responses and changing you autonomic activity (‘fight or flight’ response) resulting in an overall relaxation and a feeling of well-being.
Medical acupuncture is commonly used by medical doctors, chiropractors and physiotherapists in the treatment of chronic pain, or as an adjunct to their regular treatment regime.

What can be treated with Medical Acupuncture?

Recent research has found acupuncture to have positive results in the treatment of chronic low back pain, knee osteoarthritis, and management of chronic pain conditions. Other musculoskeletal conditions commonly treated with medical acupuncture include tendinosis, rotator cuff injuries, muscle strains, joint sprains, headaches and repetitive strain injuries. As previously mentioned, medical acupuncture helps to restore your body’s natural nerve and muscle tone, increases blood flow and provides pain relief for chronic conditions.

Typically treatments last about 20-30 minutes and the number of needles used in a treatment will vary according to the individual, duration of pain and the condition being treated. An improvement of 15% to 20% in pain sensation is often experienced after the first treatment. In general, further improvement follows within a few days; however, the effects of this technique can be immediate. Repeated treatments are necessary to see full pain relief in most cases.

Is the Treatment Painful?

Everybody has a different and unique response to acupuncture. Typically the treatment is pain-free; however some have a heightened sympathetic response to needles which results in the sensation of lightheadedness, fatigue and often sweating. The application of the needle is similar to the ‘prick’ of a mosquito bite with further tightness being related to the tightness of the tissue the needle is in. The majority of needles are imperceptible when placed in the body. Furthermore, for a completely successful outcome, the point to be treated has to be the one that reproduces the referred pain, or be a spinal segment point located on the relevant somatic or autonomic segmental levels associated with the painful area. This means that the needle placement will often recreate the pain sensation of the condition. While undesirable, it is necessary to target the source of the pain in order to fully resolve musculoskeletal conditions. However, the end result of pain resolution is always worth the slight discomfort one might experience during the course of treatment.

References:

1. Coeytaux RR, Kaufman JS, Kaptchuk TJ, Chen W, Miller WC, Callahan LF, Mann JD. A randomized, controlled trial of acupuncture for chronic daily headache. Headache. 2005 Oct;45(9):1113-23.
2. Jeun SS, Kim JS, Kim BS, Park SD, Lim EC, Choi GS, Choe BY. Acupuncture stimulation for motor cortex activities: a 3T fMRI study. Am J Chin Med. 2005;33(4):573-8.
3. La JL, Jalali S, Shami SA. Morphological studies on crushed sciatic nerve of rabbits with electroacupuncture or diclofenac sodium treatment. Am J Chin Med. 2005;33(4):663-9.
4. Lee YH, Jeong DM, Jeong SY, Lee MS. Development of a system and improvement of the stimulus pattern to discriminate the acupuncture point and meridians. Int J Neurosci. 2005 Jul;115(7):989-1002.
5. Leung A, Khadivi B, Duann JR, Cho ZH, Yaksh T. The effect of ting point (tendinomucular meridians) electroacupuncture on thermal pain: a model for studying the neuronal mechanism of acupuncture analgesia. J Altern Complement Med. 2005 Aug;11(4):653-61.
6. MJ, Tong HC. Manual acupuncture for analgesia during electromyography: a pilot study. Arch Phys Med Rehabil. 2005 Sep; 86(9):1741-4.
7. Neri I, Allais G, Schiapparelli P, Blasi I, Benedetto C, Facchinetti F. Acupuncture versus pharmacological approach to reduce Hyperemesis gravidarum discomfort. Minerva Ginecol. 2005 Aug;57(4):471-5.
8. Witt C, Brinkhaus B, Jena S, Linde K, Streng A, Wagenpfeil S, Hummelsberger J, Walther HU, Melchart D, Willich SN. Acupuncture in patients with osteoarthritis of the knee: a randomised trial. Lancet. 2005 Jul 9-15;366(9480):136-43.