It was noted during the Whitman Concussion Forum that typically, the Colorado Med Society Scale that included LOC in grades 3 and 4 only was a featured tool in many practices across the country. But there are as many definitions of "concussion" as there are dictionaries. My personal definition of the word concussion expands the role of injury to include mental as well as physical alterations to the brain. And, because traumatic vibrations inside the skull can be imparted from blows to any part of the body or without any contact whatsoever, I believe the very word concussion (however it is currently defined) is misleading as the images conjured by the general populous predominantly are exclusive to head trauma alone involving an outside force or impact. The word is Teebie: "A Traumatic Brain Episode that occurs whole or in-part due to excessive forces acted upon or initiated by a living body altering brain function" This definition allows for excessive force to occur at any area of the body and is inclusive of both physical and mental changes. It was agreed by the committee that it indeed is possible to have a concussion and not show any signs or symptoms or that an impact is necessarily required to produce those symptoms.
The genesis of my word stems from the Pellman, Viano, 2006 summary of the findings of the NFL Committee On Mild Traumatic Brain Injury which recommends the use of the phrase "Traumatic Brain Event" to describe the moment of injury. But an "Episode" is more appropriate as it alludes to further sequencing of events involved in the progression of a concussion. So start using "Teebie" to describe the occurrence of disruption of brain function through excessive force. The more it is acknowledged in paper, print, literature, and society, the greater likelihood it will be adopted by the lexicographers and become a word.
A friend of mine told me of a man he knows who plays golf. He lives, eats, sleeps, and breathes the game. He is a family man devoted to helping people find excellence within themselves through personal growth and global awareness. As an instructor of golf, this approach of cultivating your character can manifest in inner peace, an outward positive image, and yes, an improved golf game. A portion of his instruction includes being barefoot during swing drills and relying on the tactile and proprioceptive feedback to execute shots. The question was posed to me, "If the Graceyfeet insole blocks shock, does it mean I feel the ground less?"
Through the innovative use of extremely strong aramid fibers and non-newtonian materials, the Graceyfeet Cush material reduces both peak and mean vertical shock, so the highest forces are reduced and you do not feel the vibrations that are detrimental to your game. However, there are vibrational frequencies that do make it through the insole and give you the exact tactile feedback you need to determine what part and how forcefully your foot is contacting the ground.
First, some ground-work...Vibration forces input help us to perceive up from down and position in space. But excessive and repetitive vibrational forces cause pre-synaptic, reflexive, extraneous motions about the joints(1,4,6). A 2002 study using EMG, strain gauge, and plantar pressure mapping found that muscles may lose up to 10% of their strength after 35 minutes of weight-bearing exercise due to reflexive proprioceptive adjustments caused by excessive peak vibration signals at the ankle(6). Also, high peak and mean vibration forces cause reposition sense error and direction error in the low back and trunk(2,3). This means that after roughly a half-hour of sport-related vibrations, there is a 10% loss of functional strength in certain muscles, and a decrease in body positioning and directional accuracy.
Graceyfeet Cush insoles reduce peak and mean vertical forces by 30%-60%. Yes, some of the GRF is not felt, but only excessive ground reaction shock is affected. all other vibration related to temporal and spatial input is preserved. Subjective reports from clients are that kinesthetic control improves using Graceyfeet over shoes alone because they feel like they have more grip and better control of their body position at various moments during their swing. Also their ankles, knees, and back feel better.
The Graceyfeet Cush insole simply allows the vibrations necessary for a specific task to pass through so the sense of "Feel" (perceptive sensory feedback loop) and your "response" (body placement, task execution, muscle strength) actually improves. The plantar pressures are reduced, but your proprioception remains unchanged. Consider the conditions of being barefoot on soft grass; large contact surface area, improved grip, and reduced vertical forces with nothing to impede the skeleton's preferred path of progression. But put a shoe on, and vertical forces rise dramatically over smaller surface areas, muscle activity is very different, and tactile sensation is changed.
Current insole materials have a very small effect on high vibration pressures (5-10% tops). So replace the existing sock-liner with a Graceyfeet Cush insole and the environment within the shoe changes to respond more like barefoot on grass! Contact surface area is increased, vertical forces are dramatically reduced, grip is improved, and the preferred path of progression is retained. All the proprioceptive neuromuscular re-education you gained training barefoot is retained because of the similar "Feel" of Graceyfeet to barefoot on grass.Drop only the vibrations that cause fatigue and inaccuracy, quiet reflexive motions, and your performance will be enhanced through improved accuracy and timing over long duration sport activities.
The Graceyfeet insole smooths out the ride by blocking shock from below and lightly decelerating movement from above. Kevlar attenuates the shock while the medical-grade SRP (the green stuff) minimizes the effects of abstract reflex muscle activities that cause fatigue and disrupt performance.
In essence, it improves performance by normalizing plantar pressures across varying terrain and providing excellent energy return. But as with any new shoe or insert/orthotic, you do have to get used to it first.
Remember, the ability to sense where your foot is in space correlates very poorly with the ability to place your foot in a desired position. The magnitude of your muscular reaction to changes in angular velocity about a joint due to sensory input may be fine tuned when the foot is in a familiar environment and feedback is experienced in a known, controlled range.
Take a look at my blog entry on volleyball court surfaces. Peak performers will practice on the terrain they play on in the conditions they will expect to encounter. Using Graceyfeet in both your daily and your sport-shoes will maintain a symmetry of feel between activities.
Quieting the vibrations through the body allows for purposeful and focused cognitive and physical release.
Learn and adjust skills barefoot.Practice and Play in Graceyfeet.
http://dx.doi.org/10.1016/S0304-3940(99)00302-X, Vibration alters proprioception and dynamic low back stability
Proprioception, gait kinematics, and rate of loading during walking: Are they related?
Proprioception of the Ankle Joint
I wondered, do I really need a heel cup and arch when these elements were always the ones I was having to adjust for best comfort and control. For as simple as a Graceyfeet insole is to look at, the science behind it is quite extensive. Graceyfeet works because pronation and bony alignment in and of themselves do not cause pain unless there is existing physical trauma or excessive mechanical stress to the tissues. Poor alignment does produce high plantar pressures that transmit excessive vertical forces through the joints of the foot and ankle and up the chain; that is what causes the pain and prolongs healing times. This is why, for example, we place a valgus wedge (or 1st ray cut-out) under the forefoot in the presence of a plantarflexed, hypo-mobile first ray. But what if there was a material that blocked the ground reaction force (GRF), allowed the 1st ray to drop, and molded to the heel and met-heads so well that it dispersed the pressures over a larger surface-area without the need for a heelcup or special pads? This is exactly what Graceyfeet does in a 3/16" thin, flat insole. Graceyfeet drops the pressure that causes pain, maintains a preferred joint movement path, and can be used in the presence of gross deformity and existing pathology. The full-length Kevlar turns vertical forces into horizontal forces while the PPT/SRP stores and returns energy under load. If the GRF is blocked and not allowed to reach the foot, where does it go? It stays in the cleat/ground interface. This results in improved grip on dirt, turf, and court surfaces. Faster acceleration times, quicker jumps, sharper cuts, powerful push-offs, etc....This stuff digs hard and releases perfectly. This in-turn, instills confidence in a player's base of support. But they should practice in it first! Immediately he will experience what the advantages feel like, and soon they will become second nature; freeing your player's mind to focus on his assignments of play, not his feet.
Now don't get me wrong, I do believe orthotics (Heel cup, posts, wedges, MLA pads, custom molded shells, etc.) work to reduce pain, improve balance and alter the kinetics and kinematics of gait!
Graceyfeet is a tool for the toolbox to control pain and improve function. It can be complimentary to existing orthotic devices or for athletes who have soured on the use of orthotics altogether. It can go next to the skin and be cut for cast shoes, wrist pads, crown pads for helmets, slide pads, glove/mitt pads, chest pads, shoulder pads, and anywhere reduced pressures are desired. It's anti-microbial and anti-bacterial! It can be washed and dried in a machine! I can silkscreen a logo or player's name on it! It's very cool stuff.
So, you've read this far. Congratulations! You've earned the right to know more...
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Thank you Kevin Kirby, you are the gold standard.
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29. Kirby KA.: Biomechanics and the treatment of flexible flatfoot deformity in children. PBG Focus, J. Podiatric Biomechanics Group, 7:10-11, 1999.
30. Kirby KA: Conservative treatment of posterior tibial dysfunction. Podiatry Management, 19:73-82, 2000.
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33. Kirby KA: Lateral heel skive orthosis technique. Precision Intricast Newsletter. Precision Intricast, Inc., Payson, AZ, September 2004.
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36. Li CY, Imaishi K, Shiba N, Tagawa Y, Maeda T, Matsuo S, Goto T, Yamanaka K: Biomechanical evaluation of foot pressure and loading force during gait in rheumotod arthritic patients with and without foot orthoses. Kurume Med J, 47:211-217, 2000.
37. Lobmann R, Kayser R, Kasten G, Kasten U, Kluge K, Neumann W, Lehnert H: Effects of preventative footwear on foot pressure as determined by pedobarography in diabetic patients: a prospective study. Diabet Med, 18:314-319, 2001.
38. MacLean CL, Hamill J: Short and long-term influence of a custom foot orthotic intervention on lower extremity dynamics in injured runners. Annual ISB Meeting, Cleveland, September 2005.
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42. Moraros J, Hodge W: Orthotic survey: Preliminary results. JAPMA, 83:139-148, 1993.
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Loves me some Benno Nigg!
52. Nigg BM: The role of impact forces and foot pronation: a new paradigm. Clin J Sport Med, 11:2-9, 2001.
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There is no doubt that a bad case of Shin Splints can be incredibly difficult to rehab from. Shin splints are a painful condition in the lower leg involving inflammation that occurs in the anteromedial compartment (the inside, front of your shins). Shin splints are considered an over-use syndrome and can result from intense ballistic activity such as boxing, running, or plyometric exercises such as platform jumping. The symptoms for shin splints include painful tightness and/or tenderness around the tibia, especially after running or walking for long distances over hard surfaces. Shin splints are generally caused by excessive strain and stress of muscles and tendons along the shin bones (tibia and fibula) and subsequent fluid retention in the interstitial spaces of the anterior leg. There are no contractile fibers over the bone in this area to assist in pumping fluid away, only a broad fascia of connective tissue. When micro-swelling persists in this area, it causes pressure over the bone and a painful ache. Overuse of the surrounding muscles and high ground reaction forces are the most common mechanisms of injury.
Excessive motion of the subtalar joint of the feet serves to increase vertical pressures through the lower legs. Over-pronation leads to internal tibial rotation and increases the tractional forces upon the muscles and ligaments while excessive supination reduces the contact surface area of the foot and drives increased pressures up the limbs..
Rest, Ice, Elevation, Compression, and positive-flow massage are required to help alleviate shin pain; running and other strenuous activities should be avoided until the condition is minimized. Shin Splints can frequently be prevented by warming up with an appropriate stretch routine before participating in intense physical activity.
Footwear with hind-foot support and midfoot control in combination with a pressure-reducing insole is a good way to prevent and reduce the effect of shin splints, especially for boxers, football players, runners, or anyone who strikes heavily with the heels or are constantly on their toes. Orthotic insoles are useful in that they help control the foot and reduce excessive plantar pressures and unwanted vibrations. Stability in the frontal plane combined with heel cushioning has been shown to reduce impact ground reaction forces (GRF) while repositioning the force vectors and reducing their magnitude. These changes result in more comfortable weight-bearing during high impact, or long duration activity.
A blurry-eyed arrival to the conference from weeks of inspired creativity in the "Rehabilitation Arts" was met with friendly faces, kind hand-shakes and hugs. I had a wonderful time meeting and re-meeting everyone and I am told my talk went over quite well. It was titled "Pedorthic Solutions for Persons With Proteus: Phun With Pheet!" and I demonstrated the fabrication techniques I employ to make Brian Richards' custom orthotics. I took out the algebraic math and used some simple geometry to demonstrate the concept of fore-foot varus or valgus wedging for dispersing plantar pressures while simultaneously relieving large bony masses at each stage of the gait cycle. I had limited evaluation findings except for my powers of recall (I've seen this population since 1999), photos, conversations with Brian and the casts of his feet. A great many assumptions were made regarding joint position from the STJ and above but nothing beats good communication to gain a thorough understanding of a person's pathology. I employed a tissue stress approach to identify key areas of need and selected the materials that could do the job. I issued Brian his new orthotics in front of the audience and other than two small areas of fit and feel, Brian said,"It feels like I'm walking on air!" A priceless moment.
My friend Daniel was awesome in delivering a method of adjusting Crocs with a heatgun. I and the audience were raptured by his passion and creative enthusiasm. I also introduced my "Conceptual Pedorthics" approach whose philosophy states that assisting the human body in self-locomotion will improve life experience and strives to view the foot as an existential tool. This school of thought allows for open-minded, evidence-based, pedorthic foot care within the confines of the patient's functional life. Thank you, Dr. Leslie Biesecker, Kim Hoag, Julie Sapp, Barbara King, Mary Timmerman, Pam Goddard and all the great people involved in the Proteus Syndrome Foundation in one way or another. Thank you to Uneaqual Technologies, Fastcut CNC, Pel Supply, and the good folks at Podiatry-arena.com . Best of all, A cause has been found. And that was the best news all day long!
Proteus Syndrome. If you don't know, Now you do. I've worked with persons with Proteus for 14 years and I'll be speaking at the conference in October. Please read a become aware of this rare disease. Thank You!
"Dear Chris, I am in Greece and wearing my jogging shoes with the pad you made for (me) as well as the orthotic as I write this email. In fact the only reason that I am thinking about the pain I used to have is that I am writing you! Thank you, G.A."
The above is a pleasant and informative email sent to me that introduces my next topic quite nicely. How and Why the body is able to conform and tolerate an orthotic device to the point they are "forgotten" are questions clients often ask but receive few specific answers on from healthcare professionals. What my patients are mostly looking for is useful information, based in science, that explains why we recommend they slowly get used to their orthotics.
Well, it's not for functional ability of the orthotic device to 'break-in', but for the body's comfort to increase compliance in using the device. I tell them, "The foot can get used to just about anything, but we want it to get used to the RIGHT environment."
Here's HOW that happens:
Nerves of sensation are found in abundance in the Dermis layer of the skin. Meissner Corpuscles are responsible for signaling light, fast touch. Pascinian corpuscles sense deep pressure and vibration. Free nerve endings are responsible for pain and temperature changes. Proprioceptive nerves sense positional and rotational changes at the joints. These nerves work independently and in groups to let the brain know what the physical changes of the skin are and where the limb is in space. Placing an orthotic under the foot and inside a shoe has been shown to alter joint position, plantar pressure distribution, and pressure magnitude. Changes in these variables are detected by the nerves in the foot and if an abrupt or large change is experienced for too long a time, a pain threshold may be reached. This means that a device may place the foot in a desired corrective position but may also induce a pain response if the brace is not anatomically correct and is not introduced slooooowly.
So I do not say a word of the above to my client unless they ask in a way that leads me to believe they would understand those complex concepts. Instead a reply such as, ">>>To be continued<<< - CG
Let's start off by giving a few references:
Milani, TL, & Hennig, EM (1993). Pressure distribution under the foot at the take off in volleyball jumps and high jumps Fosbury Flop. In Biomechanics XIV, (pp. 874-875). Paris: International Society of Biomechanics.
Energy absorption of different court surfaces: http://www.asbweb.org/conferences/1990s/1998/86/index.html
Volleybal Biomech Differences btw Sand and Rigid surfaces in Squat Jump: http://www.ncbi.nlm.nih.gov/pubmed/15079993
Orthotics do have an effect on the angular alignment of the bones of the foot in stance and it is widely accepted that these changes translate to a change in plantar pressures and center of progression during gait. The degree or magnitude of effect on pain and function is not well known and published results are largely subjective or speculative. Too bad. But what we do know is that by altering the plantar pressures during gait, we can elicit the effect of breaking a player's cycle of loading the foot in a painful area and relieving an overused area of compensation. But what about the playing surface and how can we reduce the risk of injury occurring in the first place??
In Jumping, the softer and more compliant a surface is, the greater amount of force is transferred to the jumping surface. Additionally, the body will make angular compensations at the LE joints and hips to improve stability, increase extension moments, and launch during a jump. It would appear that the softer surface (Sand) reduces the likely hood of impact injuries but at the expense of increased loading of the support structures of the foot and ankle at angles that do not occur on a more rigid surface. Compensations such as these are highly individualized and each player will have their own method of positioning themselves for proper launch and landing. This would be enhanced in barefoot conditions v. shod.
The lesson to take away here is that an orthotic can have very little effect on the alignment of the LE on a typical sand volleyball court. Depth of sand and a billion other assumptions are being made of course, but if a team is training on sand, they should schedule their matches for sand surfaces as the body will have learned to perform on that surface. A player may actually jump higher on rigid surfaces having trained on sand, but foot placement and impact forces will be dramatically different on the rigid court and an increase in the likelihood of injury may occur. Multi-surface training and an understanding of each individual's compensations to varying court surfaces are keys to injury reduction. An orthotic with good energy return, flex, support, and a shock-absorbing sockliner should help a player adjust to the changes in plantar pressures and bony alignments that are found going from sand to more rigid court surfaces.
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Chris Gracey MPT, Cped