Flat foot or Pes planus ( may be of congenital origin ) from this image we can say that there is excessive inrolling ( pronation ) and flattening of the medial longitudinal arch...but which condition is primary, holds the key to the remedy and that's easy to find out..u just have to ask the person to take the feet of the floor and dorsiflex --> if arch appears, then it is flexible flat foot ( which means the arch is intact ) and we have to correct the excessive pronation with exercises. If the arch is flat then it is usually a difficult issue and exercises called foot gymnastics are prescribed for developing the arch. In both cases however an instep in the footwear to support the medial longitudinal arch will help prevent major complications to other joints, starting with the knee, then hip followed by the spine. to understand this, let's understand normal weight transmission (while walking ) first - 90 % of us have slight bow legs which causes the outside of the heel bone to strike first followed by a subtle in-rolling and slight flattening of the medial longitudinal arch. The mechanical reason for this physiological in-rolling is because our ankle joint (sub tibial ) is designed like a “Miter joint” which is inherently weak, but for a reason – so that the in-rolling gently shifts the weight to the medial longitudinal arch and causing it to flatten (slightly) thus dissipating the ground reactionary forces more ergonomically / physiologically and transfer of the weight upward slightly more thru the medial compartment of the knee as it is bigger and more in line with the hip joint....so that's normal. But if either the angle of the Miter joint angle is exaggerated – like in somebody with excessive bowlegs or if the stabilizing factors like the ankle ligaments are torn/weak, the feet lands as if on a knife edge and the in-rolling is exaggerated resulting in complete flattening of the medial longitudinal arch causing and in this context it’s by no means subtle.....Multiply this into every minute, hour, day……and U know that it's a potential problem by itself..... Also people who are obese will have excessive pronation on planting the feet while walking with consequent excessive flattening of the Medial longitudinal arch.....now most if not all of the weight will be transmitted upwards, through the medial compartment of the knee and this sets the stage for OA of the knee and it's sequelae ...all the way into the spine. And can we do something simple / practical to arrest or slow the development of OA in the obese population ? we often tell them to lose weight - but if it's going to be open ckt ( foot leaves the surface) ex. treadmill, then all the pounding will accelerate the problem. So as far as wt loss exercise is concerned it should be closed ckt ex. elliptical bicycle And here is something we can do immediately - prescribe a shoe that has a good insole to support the instep / medial longitudinal arch..it will help to redistribute some weight through the lateral compartment of the knee. Relevance in today’s context – These days parents are very aggressive and what their kids to take their first baby steps by age 5 months, walk and fetch the tv remote by 7 months and burn the dance floor on the first birthday. I know of a couple that had infant walkers ready even before their child was born (not kidding…they had borrowed it from their relatives b4 somebody else borrowed it). Early walking with or without infant walkers sets the stage for bow legs which is further compounded if the child is on the wrong side of the weight curve( and extreme form of which is called Blount’s disease / tibia vara – for which early walking and childhood obesity is thought to be one of the causes). A heavier infant will start walking later compared to a lighter infant…but anxious parents and an overenthusiastic pediatrician ( I am not generalising, becos many pediatricians are also among the most intelligent in our field)who looks at milestones just as mere numbers can set the stage for early onset flat-foot and the sequelae. There is another facet to this problem in our urban setup. Gone are the days when children would run around barefooted in the uneven courtyards, climb trees or jump over the school fence to play truant :grin:. Urban toddlers walk bear footed in their homes (flat surface) or when outdoors walk mostly on asphalt (again flat surface) with flat shoes (if not being pushed or carried around). No scope for development of any muscle, let alone intrinsic foot muscles.
