A Hamstring Related Foot Placing Reaction
(Why Do Football Players Suffer Hamstring Injury?)
Keith Keen BA, DipAc, DO, DC, DIBAK
Sydney, Australia
Abstract
A foot placing reaction / muscle weakness relationship is described wherein
plantar subluxated tarsals may cause hamstring weakness.
Introduction
Foot Placing Reaction (or “Magnet Reaction”) is a standard part of Applied Kinesiology
knowledge and teaching.
These foot initiated leg muscle reflexes allow bipeds to stand without toppling sideways and
to walk on the side of a hill without falling over.
The reflexes are important to the practitioner because foot subluxations may mimic lateral
sway or the foot being on a slope and cause related muscle weakness.
Current Subluxation / Muscle Weakness Relationships
Associated with Foot Placing Reaction
1.
Cuboid subluxation, or plantarwards dysfunction of the lateral longitudinal arch of the
foot, may cause weakness in the ipsilateral tensor fascia lata.
In simple terms, in the presence of a lateral or dropped cuboid, the foot proprioceptively
thinks it's everted, that is equivalent to being on the side of a hill. So to stand without
toppling down the hill the tensor fascia lata must let out a bit. This presents as weakness of
the tensor fascia lata.
2.
Navicular subluxation, or dysfunction (pronation) of the foot’s medial longitudinal
arch may cause weakness of the ipsilateral adductors. (The foot is proprioceptively inverted).
Similarly, medial or lateral subluxation of the transverse tarsals may be equivalent to body
sway as far as the joint receptors are concerned, and thus may facilitate and inhibit the same
muscles to return body balance.
The Hamstring Related Foot Placing Reaction:
Plantar subluxation of tarsals may elicit weakness in the hamstrings.
First Observation:
59 year old female. About to trek in the Andes. Being a well-trained AK patient, she came to
me because her top-of-the-range hiking boots “did not feel right”.
I tested her leg muscles with the boots on. Hamstrings were weak with boots on, strong with
boots off. Further investigation found that her hamstring was strong with boot on unlaced,
weak with the boot laced up. Furthermore the lacing weakened only the hamstring ipsilateral
to a laced up boot.
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Plantar-subluxated tarsals that challenged only when testing with the ipsilateral hamstring
were found. They did not challenge when using any other indicator muscle.
On correction of the tarsals, the boots did not affect the hamstrings even when laced as
tightly as possible.
Results of Clinical Observation
Since the instance cited above, I and my associates have found several common occurrences.
A plantar-subluxated tarsal may weaken the ipsilateral hamstring.
Only when using the ipsilateral hamstring as indicator muscle, will most plantarsubluxated tarsals test positive.
Plantar-subluxated tarsals mostly do not challenge when using any other indicator
muscle.
Conclusion:
We have all been missing tarsal subluxations unless we test with the ipsilateral hamstring !
A Corollary:
Best use ipsilateral tensor fascia lata to test for cuboid subluxation and ipsilateral adductor for
navicular subluxation.
Why Do Football Players Strain Their Hamstring?
Have you ever wondered why so many young, fit football players strain a hamstring ?
I have. It has always seemed odd to me that, with all their fitness, youth and training, so
many damage hamstrings. And why hamstrings more than other muscles?
A probable answer:
The players have plantar-subluxated tarsal(s).
The subluxations are undiagnosed due to the need to test with ipsilateral hamstring.
(an awkward test until one gets used to it).
Tight football boots are a constant challenge to the tarsals.
(boots are often laced tightly due to the studs on the sole).
Therefore they are playing with weakened hamstrings !
If you provide care for a football team:
Test your team's hamstrings with and without football boots.
If the boots affect the hamstrings:
Check and correct tarsals (using ipsilateral hamstring as indicator).
Retest their hamstrings with football boots on.
It is obvious that the principles presented apply to more than just football players. Their
example is used because the studded sole of the boots encourages tight lacing and kicking
the ball with the dorsum of the foot may cause plantar subluxated tarsals.
The first observation cited in this paper was not a football player. But her high altitude walk
to celebrate her 60th birthday was much more pleasant when her hiking boots did not turn
her hamstrings off !
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Will Dorsally Subluxated Tarsals Weaken the Quadriceps?
Dorsally subluxated tarsals are not nearly as common as plantar subluxations. I have had
only one enter my clinic in recent times. His ipsilateral quadriceps was weak.
Perhaps the hamstrings and quadriceps are related to standing uphill and downhill foot
placing reactions respectively.
Feedback Please
My clinic deals largely with learning difficulty and developmental delay since my discovery of
corrections that assist the integration of retained primitive reflexes. Thus our patient age
distribution is heavily skewed to the younger end. Plantar subluxated tarsals are less
common in the younger population.
If your practice is more sports oriented, or has a higher proportion of adults, I would
appreciate your email feedback to keith@keen.com.au Thanks in anticipation.
Keith Keen
December 2003
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