The awkward runner ?: Gait Ataxia, another cause.

Vitamin B12 deficiency: Another cause of Gait Ataxia.

Here is where our clinical background gives us another slight edge on those in the gait and movement fields. Once again we need to bring to the table another cause of gait problems.  This problem can manifest as a gait, running or simply a mild impairment of muscular coordination patterns.  There are so many people out there these days providing “care” to athletes and those that want to stay physically fit. Many of these care givers however are not in the medical field. They might be a coach, trainer, massage therapist, physical therapist, or God forbid someone you are taking advice from over the internet. The problem in giving health advice or treatment is that it is easy to do and often, if you are without a medical license, fraught with the “you cannot be aware of something that you do not know exists”.  So, if you are one of those who trains or coaches people, offers nutritional advice, stretches, massages, “activates” or uses other means without a medical license, you had best be aware that you could be missing things.  And, even if you do have a license, failure to get results is sometimes a result of something being missed diagnostically, not a failure to treat enough or not using the right techniques or therapy. This is not a dig at anyone or their passion, it is just a fact, without a medical background you just might not be exposed to the gamut of things to be aware of.  Thus, it is quite possible that “interventions” are not working because other things are lurking below the surface, things one just might not be aware of. On this note, It is never a bad idea to ask your athlete if they have had some blood work and chemistry workups in the last 12 months, especially if they are not progressing or are having some of the early subtle signs or symptoms of something bigger lurking systemically. Read on.

You will recall from our last talk on movement impairments from organic or systemic nutritional complications (Nov 10th, Gluten Gait Ataxia) that there are several metabolically driven gait and ataxia disorders. The one we are going to talk about today is Vitamin B12 deficiency ataxia (we are going to downplay the pernicious anemia thing for now to stay focused).

You will recall that the definition of ataxia is pretty broad.  Ataxia refers to an inability to coordinate bodily movements, especially movements of the muscles. Thus ataxia can manifest as a possible aberrant motor pattern, lack of coordination or subtle gait impairments such as early balance difficulties.

Vitamin B12 (aka cobalamin) is a water soluble vitamin that has a paramount role in the normal function of the central nervous system and blood formation. It is one of 8 B vitamins. Vit B12 deficiency is nothing to shrug off.  In its most severe unaddressed form it can potentially cause irreversible central nervous system damage (for you doctor-types out there you will fondly recall the long lectures on SCD (subacute combined degeneration of the spinal cord and CNS) from your favorite neurophysiology professors).  At subacute B12 levels softer symptoms can range from fatigue, depression, dizziness, memory loss, confusion, anxiety and other neurocognitive problems as well as altered executive function, ataxia (unsteady gait, balance impairment) peripheral limb or circumoral numbness or tingling.  The vagueness of these symptoms often lead to untimely diagnosis.   

Vitamin B12 occurs naturally in most animal products, but if you are one of millions of people who cannot absorb B12 efficiently, then you can begin experiencing symptoms of vitamin B12 deficiency.  And yes, to remind you once again, the symptoms are soft and vague at the start.  They are vague because it takes time for gradual degradation of the nerve’s myelin sheath, the place where Vit B12 has its impact. It is this myelin, the conductive coating on a nerve, that is necessary for accurate and timely communication between the central nervous system and muscles and organs.  And it is here that gait ataxia truly begins.  The nerves of your spinal cord rely on a steady in and outflow of information from your nerve sensors throughout your body.  Messages to and from the nerves in your limbs are conducted along the spinal cord (particuularly in the spino cerebellar and dorsal column tracts: See Dr Ivo’s neuromechanics lectures for a review of these here ) and to the brain, thus controlling gross and fine motor tasks such as running, walking, dancing, climbing, skipping, or tapping your feet.  Nerve damage causes these signals to become misinterpreted, resulting in poor coordination, or gait ataxia.

Here are some signs and symptoms of gait ataxia:

  • Unsteady gait, difficulty walking without stumbling
  • Difficulty staying balanced on one leg
  • Trembling awkward movements, clumsiness
  • Muscular weakness in the legs and arms
  • impaired motor tasks
  • Spasticity
  • Hypotension (low blood pressure)
  • Vision problems
  • Numbness / tingling; particularly around the mouth


So that is our little talk on gait ataxia and its relation to Vit B12.  It is a quite in-depth topic to be honest but we want to keep this concise.  In terms of recommendations, we are not going to make any here today.  The recommended daily allowances are easy to find on the internet.  Two things you can do,  you should improve your diet (we all can) and get yearly blood work studies.  If you are vegan (unless you are a lacto-ovo vegetarian) or do not consume much in the way of animal based food products you need to consider B12 supplementation (that or start eating termites - B12 rich !).  You should also be aware that there are many things that can alter Vit B12 absorption /integration such as birth control pills, alcohol consumption, nicotine, medications, antibiotics and many others. These are consumables that increase your risk of B12 problems and thus risk for gait ataxia and the other B12 related issues.  Most of the time, ataxia is a difficult diagnosis to make (unless a copious single event of alcohol consumption at the local pub is the culprit). 

Bottom line.  There is so much more to Vitamin B12 deficiency but this was not meant to be that forum.  Ataxia and gait alterations are nothing to dismiss, especially in the elderly.  There are many causes of ataxia and this is just another that we wanted to bring to light.  The nervous system and muscular systems have some definite source needs and Vit B12 is one of them.  Without the right fuel these systems will begin to show impairments, soft impairments at first which could be the difference in a high level athlete’s performance.  If your parents, patients, athletes or those you know are expressing some vague and subtle symptoms, educate them. Better yet, send them off to their doctor if symptoms persist, rather than handing them a bottle of Gatorade and casually telling them they are probably just dehydrated, anemic from low iron or low on electrolytes …. as it so often occurs.

Shawn and Ivo, The Gait Doctors