Lately I've observed a surge in the number of my patients wearing athletic shoes with rocker forefoot and negative heels. Sketchers makes one of these, and as I interview patients the vast majority are very happy with the performance of these shoes. They describe a short break-in period with early calf ache (likely secondary to the increased calf function with decreased heel stability) but then feel very comfortable. Pathologies that patients have noticed improvement with these shoes in my practice have been predominantly plantar fasciitis/fasciosis and lesser metatarsalgia. I can see the reason why theoretically these shoes may be beneficial (decreased forefoot pressures with the forefoot rocker and maybe a decrease in equinus with the forced stretch). Examining these shoes myself I've found them to have supportive heel cups, more rigid shanks, and appropriate toe box bending - all good things in my experience. I haven't seen any research behind these shoes, though.
Is anyone aware of some better science behind these shoes? Do you suggest them in your practice and if so in what patient population? Do those biomechanics experts out there have any comments?
I guess I may qualify as a biomechanical expert but I consider myself a podiatrist incorporating foot structure and function as the fundamental base for my EBP.
Podiatrists have been writing Rx's to pedorthists and shoe repair clerks to add rocker bottoms to shoes for many, many years, as a last resort for feet with irreversible biomechanical pathology.
Examples would be post ankle fusion, advanced autoimmune arthritis, Charcot Feet and end stage pathological flat feet.
The principle is that one or more of the intrinsic rockers of the foot (Dananberg) is irreversibly damaged.
The calcaneal rocker
The talar dome rocker or
The 1st met head rocker
are not capable of allowing the swinging leg to move forward over the planted foot in the rearfoot contact gait cycle.
It is an heroic, last ditch effort, short of additional surgery, to drive a more normal gait from these individuals because it leads to acceptable reductions in function and quality of life.
The rocker of the shoe is REPLACING the mechanical rockers of the foot that will never work again.
In faulty mechanics (one simplistic example is FHL) the gait cycle is compensatorily weak and the non functioning rocker of the foot is dampening the ability for the hip and gluteal muscles to work as the gait pattern is shortened and perversed.
The increased foot rocker function that occurs when the exercise shoe rocker is used instead causes activation of the pelvic, gluteal and lower back muscles, hence the research that when you wear rocker soles you will use more of these muscle and the claims of + effects when exercising with rocker shoes but it will allow the patients underlying biomechanical pathology to worsen (Grade 1-4 FHL) eventually marrying the patient to the rocker shoe or a life of suffering.
In addition, when a rocker shoe is used for other functional cycles during ones lifetime, such as forefoot contact gait, moving sideways, backwards, lifting, etc. these activities would be greatly dampened and the patient would be exposed to injury. So rockers are only good for walking and very little else. Try playing basketball on a rocker shoe and I'll see you as an emergency add on the next day.
If you are practicing a level of biomechanics that allows you to improve performance of muscle engines and natal foot type specigic pathology, such as The Foot Centering Theory (personal bias) then there are other things to do short of rocker bottom therapy before becoming the practitioner that married the patient to a reduced quality of life in order to reduce or avoid the pain of FHL as a complaint (pathology specific care).
There are adjunctive uses for rocker shoes in therapeusis that can be discussed at another moment but in my opinion, they have specific applications and should be used as one would use roller skates to improve speed of getting from point A to point B instread of rearfoot contact gait but not as a substitute for healthy internal mechanics.
If you actually believe that a rocker is the best method of function for human feet, why is a midfoot charcot foot so pathological biomechanically?
I look forward to other opinions.