Some stuff you need to know about running spikes.

I see many track runners in my office, from middle school all the way into the USA Masters Division.  A few years ago one of the top USA Masters Milers came to see me on Friday before heading off to a national meet. He showed me some of his spikes (see pics above) and complained the there was something off on the spikes on the left, the Nike Mambas.  The shoe to the right is the Nike Zoom Miler.

You need to understand a bit of the physics of running turns to understand what is missing for this runner in this pair of spikes.  Things do change if you are running on a sloped track, but those are only found indoors and are not all that common to run on for most folks so we will stick with the thinking on flat tracks.

What you should be able to easily detect is that the Nike Mamba’s are missing the lateral 5th metatarsal forefoot spike on the cleat plate.  And you need to then realize that this is the right shoe, so it is the outside foot/leg on the track. It is the foot that will be pushing off harder from the outside on the turns to keep the centripetal forces of running a curve from allowing the runner to fall off the curve into the outer lanes. This right foot will always be pushing from outside to inside to maintain the body’s progression in the desired lane, when running the curves.

Think about it for a minute. In order to run in a circle, or a curve in this situation, the outside foot always has the tendancy to be more inverted to keep foot contact on the ground. This is where a Forefoot varus MIGHT come in handy ! This means the foot will be tipped to the outside a little, because of the curve and because the body will be leaning into the center of the track on the curves. Thus the foot and shoe will be relying on more lateral foot pressures to drive the body mass back into the lane since centripetal forces will always be driving you laterally out of the lane.  Thus, the lateral spikes on the right foot must be accommodating.  In the case of the Mamba shoe. there is only a sheet of black hard plastic over the midshaft-head of the 5th Metatarsal on the lateral foot. It is no wonder the runner was feeling like he was slipping on the turns (the front of the midfoot was not anchored to the ground, only the forefoot due to the spikes in that location). You can see clear evidence of the lateral slipping in the picture. Can you see the orange/brown patch where he was slipping ? A spike there in that area would have been wonderful.  Slipping is a power leak and a risk for injury.  If the foot is trying to gain purchase into/onto the track with the foot inverted there needs to be traction at that lateral foot, what is referred to as the Lateral Column.  You can see why the Nike Zoom Miler was a better choice, there is a nice spike placement under the lateral foot for just this measure, and there is no evidence of slippage wear.  He told me that the Mamba was a steeplechase designed shoe but we still both felt that the issue remained relevant even in that event. The Nike website however states that “the Nike Zoom Mamba Men’s Track and Field Shoe is perfect for the 800-5000m track athlete” so we think they have missed an issue here in our opinion.

I could make a better case for the Mambas if  they were for a 100m straight run but I would still like a 5th metatarsal /lateral spike where there isn’t one.  I will occasionally file spikes to get the perfect feel for the athlete.  It is usually the 5th metatarsal and 1st metatarsal spikes I mess with, merely to help hone the athletes feel on the track. The problem is that each track has a different feel so it is less of an occurrence in recent years.

It is good to know your shoes, it is good to know your physics. It is great to know them both and melt them together to solve problems.  Not all spikes are created equal, not all tracks are the same, not all events are the same and certainly not all feet and the athlete’s who own them are the same.  And on the topic of Forefoot Foot types, both the forefoot varus and forefoot valgus foot might have a problem with the Mamba’s depending on their strength, skill and strategies for ground purchase.  Hopefully your shoe store and your track and cross country coaches know these issues. You might want to bring this blog post to their attention however, just in case.

Dr. Shawn Allen

Tom Purvis hits some strong points in this video about squatting, hip hinges, ankle dorsiflexion, and movement as a whole.  * Keep in mind, this is all sagittal plane stuff….. it gets far more complicated when there are lateral (frontal) plane or rotational (axial) considerations ….. these are the “knees out” dialogues and debates you have read over and over on the web in the last year.

Dr. Shawn Allen

addendum:

Food for thought after posting today’s Tom Purvis squat video.

Could this study below translate into the statement/question: 

“attempting to achieve sufficient dorsiflexion through the combined ‘foot pronation-ankle dorsiflexion’ mechanism, as opposed to just dorsiflexion from the ankle mortise joint alone, may change the dynamics of the entire limb…. in this case, hip flexion range observation. Is this because when dorsiflexion is cheated via foot pronation, instead of just ankle dorsiflexion, there is more internal tibia/femoral spin than would normally occur from just sagittal ankle hinging which can in turn impair terminal hip flexion range via impingement type action ? I think so. It would be cool to see what would have happened in the study had the pronating clients been shown my foot tripod restoration exercise (it’s on youtube).   -Dr. Allen

here is some new research on this point, for what it is worth.  It keeps the mind thinking though.

J Phys Ther Sci.  2015 Jan;27(1):285-7. doi: 10.1589/jpts.27.285. Epub 2015 Jan 9.The kinematics of the lower leg in the sagittal plane during downward squatting in persons with pronated feet.  Lee,Koh da,  Kim 

Abstract

[Purpose] This study aimed to examine changes in lower extremity kinematics in the sagittal plane during downward squatting by subjects with pronated feet. [Subjects and Methods] This study selected 10 subjects each with normal and pronated feet using a navicular drop test. The subjects performed downward squatting, in which the knee joints flex 90° in a standing position. We recorded the angles of the hip, knee, and ankle joint in the sagittal plane through motion analysis. For the analysis, the squatting phase was divided into phase 1 (initial squat), phase 2 (middle squat), and phase 3 (terminal squat) according to the timing of downward squatting. [Results] In the pronated foot group comparison with the normal group, thehip joint flexion angle decreased significantly in phases 2 and 3. The dorsiflexion angle of the ankle joint increased significantly in phase 3. The flexion angle of the knee joint did not differ between groups in any of the phases. [Conclusion] The pronated foot group utilized a different squat movement strategy from that of the normal foot group in the sagittal plane.

Rewiring.

The peripheral and central nervous systems are functionally
integrated regarding the consequences of a nerve injury: a
peripheral nerve lesion always results in profound and long lasting
central modifications and reorganization. (Kaas, 1991)
Does there need to be a lesion though ? A functional lesion will force changes just like an ablative lesion. Altered gait that persists from a sprained ankle or a painful knee will force central modifications and reorganization. This is why resolution of pain and aberrant function is critical. If you rehab to 80% you leave 20% on the table and that gets rewired into the system as the new norm. Remember, the entire system is watching, learning, adapting and rewiring all the time. This is why you must have a team in place to resolve all, if possible, of your client’s deficits. If you leave 20% of a problem on the table, and add endurance and strength to the “80%resolved:20%remaining”, you reorganize the central nervous system with that as the assumed norm moving forward. From this point forward, this is the architecture that all new patterns and forms are built from.  This sets up for long term rewiring of all of the connected parts, from motor, sensory, visual, gait, proprioceptive, vestibular and the list goes on and on. If you have ever wondered how a client can have so many areas of pain and dysfunction you might want to go back into their history and ask them if there was a single injury or event that occurred after which all their new problems started to stack up. 

If you are a gait analysis junkie, remember this principle above. All of the things you see in a person’s gait are not unconnected in many cases.  Much of what you see is a compensation around their problems, not the actual problem. 

Remember this principle: the peripheral nervous system attempts to repair by regrowth, the central nervous system attempts to repair by re-routing and reorganizing.

Dr. Shawn Allen

Our neurology mentor, Dr. Carrick discusses the vestibular system and what can go wrong with it and what happens to our locomotion system when it doesn’t function properly.  

Know this gait, memorize it.  It is NOT a Parkinsonian gait. 

Here is what you need to know about the gait presentation in Normopressure hydrocephalus (NPH):

The gait changes are often subtle and progress as NPH progresses because of the changes in the brains ventricular tissues eventually compromising the sensory-motor tracts.
Early gait changes, MILD, may show a cautious gait. Steps length and stride length may be slowed and shortened. The gait may begin to show signs of being deliberate and calculated, less fluid and free. The appearance of unsteadiness or balance challenges may prevail. Once simple environmental obstacles may now present as challenges, things like curbs, stairs, weaving between tables in restaurants or wide open spaces where there is nothing to grasp onto for stability. Weakness and tiredness of the legs may also be part of the complaint, although examination discloses no paresis or ataxia. (Ropper)  A walking aid such as a cane may add comfort but often appears to be rarely used.

As the gait changes progress into the more MODERATE to ADVANCED, the walking aids used often progress into quad walkers.  Wheelchairs are needed in more difficult places or when fatigue is growing factor.  As the gait challenges progress, the careful observer will note a more obvious reduction in step and stride length, a head down posture, less dual tasking engagement during gait execution, slowed walking speed, reduced foot-floor clearance, shuffling gait (keeping the feet more engaged to the ground, this can be a Parkinsonian-type gait mis-read, there will be no tremor or rigidity), searches for stable external cues (reaching for railings, a kind arm or hand, touching walls etc), widening of the feet (broad based stance), and fears of falling backward.

In the most ADVANCED gait impairments, the fear of falling can become too great. There may even be an inability to engage sit-stand-walk motor patterns and the fatigue of the limbs may be too advanced to even stand let along walk. This stage is referred to as Hydrocephalic astasia-abasia (Ropper).  

Normopressure Hydrocephalus is a serious issue if left unrecognized and untreated.  NPH must be diagnosed early on since a delay in reducing the pressure on the cortical tissues can lead to permanency of disease and dysfunction.  According to Poca there can be a wide range of successes and failures in symptom remediation, but there is clearly a time dependency on early diagnosis. Thus, clearly recognizing any early gait changes and behaviors prior to advancing incontinence and mental decline is paramount.

Dr. Shawn Allen, … one of “the gait guys”

Some of the above was inspired and summarized by this great article, from the Boston Globe.  

References:

1. Marmarou, Anthony; Young, Harold F.; Aygok, Gunes A. (1 April 2007). “Estimated incidence of normal-pressure hydrocephalus and shunt outcome in patients residing in assisted-living and extended-care facilities”. Neurosurgical FOCUS 22 (4): 1–8.

2. Ropper, A.H. & Samuels, M.A. (2009). Adams and Victor’s Principles of Neurology (9th edition). New York, NY: McGraw-Hill Medical.

3. Poca, Maria A.; Mataró, Maria; Matarín, Maria Del Mar; Arikan, Fuat; Junqué, Carmen; Sahuquillo, Juan (1 May 2004). “Is the placement of shunts in patients with idiopathic normal pressure hydrocephalus worth the risk? Results of a study based on continuous monitoring of intracranial pressure”. Journal of Neurosurgery 100 (5): 855–866.

4. Am J Phys Med Rehabil. 2008 Jan;87(1):39-45.
Objective assessment of gait in normal-pressure hydrocephalus.
Williams MA1, Thomas G, de Lateur B, Imteyaz H, Rose JG, Shore WS, Kharkar S, Rigamonti D.

5. Clin Neurophysiol. 2000 Sep;111(9):1678-86.
Gait analysis in idiopathic normal pressure hydrocephalus—which parameters respond to the CSF tap test?
Stolze H1, Kuhtz-Buschbeck JP, Drücke H, Jöhnk K, Diercks C, Palmié S, Mehdorn HM, Illert M, Deuschl G.

6.Rev Neurol (Paris). 2001 Nov;157(11 Pt 1):1416-9.
[Postural and locomotor evaluation of normal pressure hydrocephalus: a case report]. Mesure S1, Donnet A, Azulay JP, Pouget J, Grisoli F.

7.J Neurol Neurosurg Psychiatry. 2001 Mar;70(3):289-97.
Comparative analysis of the gait disorder of normal pressure hydrocephalus and Parkinson’s disease.
Stolze H1, Kuhtz-Buschbeck JP, Drücke H, Jöhnk K, Illert M, Deuschl G.

#normopressure hydrocephalus

#NPH

#gait problems

#balance

#incontinence

#dementia

#parkinsons

#parkinsons disease

#falls

#balance problems

#alzheimers

“If the software in your brain does not acknowledge the change in hardware – the better moving joint, the more elastic muscle, the better firing pattern between your stabilizers and prime movers – it does not matter.” – Gray Cook

We could not agree more. No matter how much table work you do or how much rehab you do, if you do not teach your client how to use the changes in walking, running, locomotion through specific retraining, then the changes are useless. Newly acquired skills that are not made accessible to meaningful locomotion were a waste of time.

A Wobble in the System: The Gait Changes in Normopressure Hydrocephalus

Can you afford to miss this diagnosis ? 

Today, the gait changes in NPH are discussed because as with many neurologic disorders and diseases, subtle gait changes are the first signs. And, in this disorder, you have to catch the gait changes early on in order to give your client the greatest changes of full recovery.   Today we couple this blog post with a great video story of a missed case study of NPH.

Normopressure hydrocephalus (NPH) consists of the triad of :

1. gait disturbance
2. urinary incontinence
3. dementia or mental decline

In the most general terms, Normal pressure hydrocephalus (NPH), also referred to as symptomatic hydrocephalus, is caused by a decreased absorption of cerebrospinal fluid (CSF). The resultant increased intracranial pressure can cause ventriculomegaly.  In NPH patients, the pressure remains just slightly elevated, but enough to create pressure on the cortical tissues of the brain causing the symptoms above. The vagueness of this problem and its seemingly random symptoms is primarily why this disorder is often missed or misdiagnosed as dementia, Parkinson’s or Alzheimers disorders.

As discussed previously, many early neurological diseases and disorders softly present with early gait changes. And, as in NPH, gait changes may be the earliest symptom of the 3 mentioned earlier. One’s ability to know, observe and recognize abnormal gait patterns coupled with a good historical interview and physical exam can often tease out the earliest manifestation of NPH.

Here is what you need to know about the gait presentation in NPH:

The gait changes are often subtle and progress as NPH progresses because of the changes in the brains ventricular tissues eventually compromising the sensory-motor tracts.
Early gait changes, MILD, may show a cautious gait. Steps length and stride length may be slowed and shortened. The gait may begin to show signs of being deliberate and calculated, less fluid and free. The appearance of unsteadiness or balance challenges may prevail. Once simple environmental obstacles may now present as challenges, things like curbs, stairs, weaving between tables in restaurants or wide open spaces where there is nothing to grasp onto for stability. Weakness and tiredness of the legs may also be part of the complaint, although examination discloses no paresis or ataxia. (Ropper)  A walking aid such as a cane may add comfort but often appears to be rarely used.

As the gait changes progress into the more MODERATE to ADVANCED, the walking aids used often progress into quad walkers.  Wheelchairs are needed in more difficult places or when fatigue is growing factor.  As the gait challenges progress, the careful observer will note a more obvious reduction in step and stride length, a head down posture, less dual tasking engagement during gait execution, slowed walking speed, reduced foot-floor clearance, shuffling gait (keeping the feet more engaged to the ground, this can be a Parkinsonian-type gait mis-read, there will be no tremor or rigidity), searches for stable external cues (reaching for railings, a kind arm or hand, touching walls etc), widening of the feet (broad based stance), and fears of falling backward.

In the most ADVANCED gait impairments, the fear of falling can become too great. There may even be an inability to engage sit-stand-walk motor patterns and the fatigue of the limbs may be too advanced to even stand let along walk. This stage is referred to as Hydrocephalic astasia-abasia (Ropper).  

Normopressure Hydrocephalus is a serious issue if left unrecognized and untreated. Here is yet another reason why you must be familiar with this problem:

“Patients with dementia who are confined to a nursing home and may have undiagnosed NPH can possibly become independent again once treated. So far only one study was able to evaluate the prevalence of NPH, both diagnosed and undiagnosed, among residents of assisted-living facilities, showing a prevalence in 9 to 14% of the residents.” – Marmarou

One’s lack of awareness and knowledge, are one’s greatest enemies. If you don’t know something exists, because you’ve never studied or learned it, how can you be aware of it ? If you’re not spending enough time examining a client, you might be unaware of an issue even though you may be knowledgeable about the issue. One must have both awareness and knowledge. One must also be aware that compensations are the way of the body. What you see is not your client’s problem. It is their strategy to cope.

NPH must be diagnosed early on since a delay in reducing the pressure on the cortical tissues can lead to permanency of disease and dysfunction.  According to Poca there can be a wide range of successes and failures in symptom remediation, but there is clearly a time dependency on early diagnosis. Thus, clearly recognizing any early gait changes and behaviors prior to advancing incontinence and mental decline is paramount.

Bonus: here is a little bonus tidbit for my fellow neuro gait friends. 

Stolze (7) study conclusion: “The gait pattern in normal pressure hydrocephalus is clearly distinguishable from the gait of Parkinson’s disease. As well as the basal ganglia output connections, other pathways and structures most likely in the frontal lobes are responsible for the gait pattern and especially the disturbed dynamic equilibrium in normal pressure hydrocephalus. Hypokinesia and its responsiveness to external cues in both diseases are assumed to be an expression of a disturbed motor planning.”

Dr. Shawn Allen, … one of “the gait guys”

Some of the above was inspired and summarized by this great article, from the Boston Globe.  

References:

1. Marmarou, Anthony; Young, Harold F.; Aygok, Gunes A. (1 April 2007). “Estimated incidence of normal-pressure hydrocephalus and shunt outcome in patients residing in assisted-living and extended-care facilities”. Neurosurgical FOCUS 22 (4): 1–8.

2. Ropper, A.H. & Samuels, M.A. (2009). Adams and Victor’s Principles of Neurology (9th edition). New York, NY: McGraw-Hill Medical.

3. Poca, Maria A.; Mataró, Maria; Matarín, Maria Del Mar; Arikan, Fuat; Junqué, Carmen; Sahuquillo, Juan (1 May 2004). “Is the placement of shunts in patients with idiopathic normal pressure hydrocephalus worth the risk? Results of a study based on continuous monitoring of intracranial pressure”. Journal of Neurosurgery 100 (5): 855–866.

4. Am J Phys Med Rehabil. 2008 Jan;87(1):39-45.
Objective assessment of gait in normal-pressure hydrocephalus.
Williams MA1, Thomas G, de Lateur B, Imteyaz H, Rose JG, Shore WS, Kharkar S, Rigamonti D.

5. Clin Neurophysiol. 2000 Sep;111(9):1678-86.
Gait analysis in idiopathic normal pressure hydrocephalus—which parameters respond to the CSF tap test?
Stolze H1, Kuhtz-Buschbeck JP, Drücke H, Jöhnk K, Diercks C, Palmié S, Mehdorn HM, Illert M, Deuschl G.

6.Rev Neurol (Paris). 2001 Nov;157(11 Pt 1):1416-9.
[Postural and locomotor evaluation of normal pressure hydrocephalus: a case report]. Mesure S1, Donnet A, Azulay JP, Pouget J, Grisoli F.

7.J Neurol Neurosurg Psychiatry. 2001 Mar;70(3):289-97.
Comparative analysis of the gait disorder of normal pressure hydrocephalus and Parkinson’s disease.
Stolze H1, Kuhtz-Buschbeck JP, Drücke H, Jöhnk K, Illert M, Deuschl G.