Finite Finite Element model (LSDYNA) of the human head showing the maximum principal strain in the sagittal plane (Kleiven et al. 2003). Software: LSDYNA by courtesy of ERAB, Sweden.
It was in 1997 that Swedish neurosurgeon Hans von Holst started wondering about how helmets were generally constructed. He had worked on skull injuries for the WHO in Geneva for five years and realised that the protection against brain damage was not good enough. The helmet’s lack of correct protection had devastating consequences for many people.
Hans von Holst contacted Peter Halldin, researcher at the Royal Institute of Technology, with a view to them trying to develop a technology that could provide more effective protection. The idea was to look more closely at the head’s anatomy and physiology and copy the body’s own protection system.
Their sights were set on better protection against the type of blow to the brain that produces the most severe injuries – rotational acceleration. This force is caused by an oblique impact with the ground, in other words exactly what happens in a real-life accident.
This called into question the most basic assumptions on which helmet development and testing had been based all these years – and not least how helmet regulations had been formulated. The focus had always been on providing protection against vertical impact with the ground.
In other words, helmets had been designed, tested and approved based on a principle at odds with the reality of accidents on the road.
Together, Peter Halldin and Hans von Holst developed a technology that involved building in a cushion or friction layer which would provide unique and much improved protection for the brain, whether the helmet was for a horserider, motorcyclist or other user.
Out of this work came the name MIPS, an abbreviation of the innovative concept and function: Multi-directional Impact Protection System.
How you fall, if you fall.
Conventional helmets are tested by dropping them vertically onto a rigid surface. MIPS has had 15 years of study and testing in Sweden by some of the world’s leading researchers and neurosurgeons, based on a different principle – reality. Because in reality when you fall, your head most often hits the ground at an angle, creating a rotation in the brain, which in turn can cause major damage. With MIPS, the helmet absorbs much of that damaging rotational energy, offering you radically better protection. And if, against all the odds, you do fall vertically onto your head, a helmet with MIPS will protect you just as well as an ordinary helmet.
MIPS imitates the brain’s own protection system and sets a new standard.
The secret behind MIPS’ unique patent comes from the human brain, which is now into its 150,000th year. The brain is surrounded by a low-friction cushion of cerebrospinal fluid. MIPS imitates the brain’s way of protecting itself by giving the helmet its own low-friction layer between the outer shell and the liner, to absorb much of the energy created by an oblique blow to the head. The combination of the brain’s own protection and MIPS therefore ensures maximum protection. Very simple and very effective.
By concentrating their efforts on MIPS technology the Swedish researchers are designing anti-rotational aspects into helmet configuration, which I believe is the best way to protect the integrity of our brain’s architecture. The highlighted finite element analysis image is in the sagittal plane, from the latin word sagitta, or arrow, in this case the left right configuration of the human body. The other planes normally viewed are the transverse plane,also termed the axial plane comprising the surface created through the eyes and ears perpendicular to the sagittal. Finally there is the coronal plane which is at the intersection of both the sagittal plane to the transverse plane. All these planes are the reference frames within how brain imaging is normally viewed. That is a problem. This kind of imposed cartography of the brain’s architecture reduces the 3 dimensional aspect into convenient slices which do not in fact match within the cellular arrangement. Think of our brain as a sculpture. There are elements depending on the scale that you examine that cross from one plane into another plane. All of the cerebrovortex essays have stressed the essence of a floating tension net at the core of the guided assembly creating a human brain, what I have termed the Snelson floating tension net. The specific critical aspect within tensegrity architecture is there is a left volume joined with a right volume in floating tension. All creatures on Earth share this symmetric body plan. In a previous essay I explored this approach as:
Yakovelian torque, The Snelson twist from the October 12, 2012 cerebrovotex entry. But floating tension is not conveniently restricted to planes of intersection like a sagittal plane or an axial plane.
I will emphasize my point here again. Due to the asymmetry imposed on a left-right brain plan there is an inherent torque capacity that would be viewed as the brain rotating on itself. If you attempt to capture this rotation it will be very very difficult technically because it will always return to its resting state. But recall also from another a previous essay from Rick Hogue’s gorgeous cine MRI work of the brain pulsing in pace to the cardiac cycle which cause the cerebral spinal fluid to move in its circuit when we both worked in the Brain Imaging Department at the Montreal Neurological Institute, our brain moves as our heart moves. So slicing a brain into static pictures reduces our appreciation of the pulsing brain positions within the skull, since tension balance is essentially invisible but at the same time present. The human brain is also what I will term a tethered object with all of the cranial nerves attaching into the brain stem from their passages through the base bone of the cranial vault. The astronauts in their long duration space flights have shown that when the gravity vector is no longer present within their cranium the ocular nerve is strained, and contorted strongly affecting the vision of the astronauts. Along the same line of reasoning the nerves that control the eye muscles, the occulomotor nerve appears also to be strained. What the astronauts call ‘space eyes’ appears to mimic a brain concussion with such micro-gravity brain strain. But what the astronauts are revealing is also a strong visual component to such brain concussion mimic effects. I am beginning to separate out a brain concussion as both an eye strain event plus a brain strain event. There is a robust reason that I call my web site cerebrovortex, it’s all about the Snelson twist inherent within the brain’s capacity for self rotation. So far this self rotation behaviour is not appreciated within the scientific community despite the heritage evidence of evolution’s design from the early beginnings eons ago. Although some researcher groups have actually reported such brain rotation as circumferential strain.
Grids of tag lines (HARP contours) showing “clockwise” shear deformation of the brain relative to the skull in subject S1. Displacements are scaled by a factor of five for visualization.
The above image is from the report, Deformation of The Human Brain Induced by Mild Angular Head Acceleration, J Biomech 2008; 41(2) 307-315, one of their strongest observations is the following: “Because the brain is tethered to the skull by vessels and membraneous connections (e.g., arachnoid granulations) at its base and surface, the decelerating torque is transmitted to the brain. Deformation is dominated by radial-circumferential shear; Figure 7 captures an opposite pattern of shear deformation as the brain nearly reverses this change of shape during viscoelastic oscillations.”
“Grids of tag lines (HARP contours) showing “counterclockwise” shear deformation of the brain as it undergoes viscoelastic oscillation in subject S1. Displacements are scaled by a factor of five for visualization.” What do you think happens at 100% contact ‘heading’ a soccer ball in terms of circumferential torque within the brain ? Brain rotation is not really a new concept, according to these angular brain impact mimic authors, “Shear strains due to angular acceleration of the skull have been hypothesized to be especially important in TBI. Holbourn (1943) showed that rotation of the human skull could cause large deformations of a gel housed within its cranial cavity. Pudenz and Shelden (1946) supported Holbourn’s claims through visualization of the surface of animal brains. They replaced the top half of a monkey skull with transparent plastic, and filmed the deformation of the brain during linear acceleration.”
These elegant images are from volunteers whose heads were torqued inside a MRI imaging machine to induce angular acceleration at approximately a 1o% of ‘heading’ a soccer ball. So the distortion images are the shapes of circumferential strain inside the brain’s anatomy in the axial or circumferential plane of reference. What is significant is the observation of rotation in one direction then a return counter rotation in the other direction. The axis of rotation is in the eye-ear/axial plane that will pull on cranial nerves attached as if at the center hub of a wheel, impinging into the brain stem where the attachments are linked. If we consider the Snelson twist such a torque now we have our critical observation. If I can find this information on a few moments notice in Google, why do helmet manufactures especially football manufactures not design against rotation? For this reason the Swedish MIPS researchers are doing the appropriate design approach toward helmet configuration by attempting to reduce such circumferential shear deformation stress within the viscoelastic behaviour of a angular accelerated brain.
The Swedish researchers are using the idea of the cerebral spinal fluid compartment as a shock absorbing capacity in their rotation centric strategy for helmet design. But the helmet design is definitely proceeding again along the line of how Nature protects a coconut, with a configuration of soft-hard-soft from surviving a 150 ft fall from its tree perch. The critical aspect is protect the head from rotation effects. Layering first with a Guardian Cap outer layer offering a gel filled cover then a deformable auxetic layer flexible rigid to displace focal contact into dispersive forces over the entire surface into a separate inner layer that counter rotates would be the design approach I would take if I were to protect my children. That is the focus of our research, to share our hard won knowledge to better protect against concussion rotation for all children. That is my heart felt message for the New Year !