The Fall 93 newsletter described metatarsalgia as a painful condition of the met heads and/or the soft tissues directly under the met heads, related to direct pressure and shear forces. Thinning and displacement of the protective plantar fat pad, rigid (plantarflexed) met heads, hypermobility of the 1st ray, poor fitting or hard, thin soled shoes, hard walking surfaces, as well as other factors, contribute to the gradual wear and tear process of metatarsalgia.
Symptoms of metatarsalgia will often resolve with the application of any one of several well known elements, for example, wearing a better pair of shoes, wearing lower heeled pumps, or installing a metatarsal pad. When metatarsalgia is viewed as a wear and tear process, a singular treatment may treat immediate symptoms effectively but may do little to minimize more significant factors contributing to this problem.
Proper footwear cannot be overemphasized. It is difficult to find well-constructed shoes that “look good,”and even harder to find competent fitters in many areas. Each foot is unique, so no one shoe works for everyone. Patients with wider feet have more forefoot problems, partly because they must fit their shoes extra long to get proper width, or extra tight to keep the shoe from slipping off the heel. When shoe length is too short or too long, the bending point of the shoe (ball break) does not match the natural metarsal break (1st MTP joint line) of the foot. Both met heads and MTP joints are chronically dysfunctional inthese cases.
Target when your patient is on their feet the most, and prescribe for that period. Usually this is during fitness activities, shopping, and weekends around the house for most office workers, and during work for those required to stand or walk all day on the job.
Running shoes have pros and cons, but some are excellent in that they have a thick EVA rubber sole that is in direct contact with the foot (slip-lasted). This allows not only direct cushioning, but the ability of rigid metatarsals to “burrow” down into the EVA after a few weeks thus evening the force distribution across the metatarsals. This effect however only lasts a few months before the EVA breaks down so regular shoe replacement should be done before, or as soon after, symptoms reappear, as little as 6 months in a runner, to 2 years in a light, less active person.
Specific running and walking shoes have a certain amount of “rocker” sole construction, which allows the forefoot of the shoe to roll more so than bend, thus reducing the amount of direct weight on specific met heads.
Rocker Soles, Met Bars:
Certain types of soles can be removed temporarily to allow the installation of an extra full length layer of soling material to exagerate, or create, the “rocker” effect for the shoe.
The thickest point of the rocker is just behind the met heads, after which the sole quickly tapers. Met bars are similar but are installed external to the original shoe, and are one of the few worthwhile shoe modifications that can be done to pumps. Although effective and less expensive, met bars breakdown quickly, and tend to catch on carpets.
Use rocker soles and met bars as the next step after met pads, orthotics, footwear changes etc. have been tried, or in severe initial conditions.
Metatarsal Pads and Wells:
A met pad pushes up from just behind the met heads, to reestablish the normal convex nature of the metatarsal arch, resulting in a more even distribution of weight bearing.
Since some metatarsals are not flexible, but rigid, they cannot be pushed up without excessive pressure on that ray (one of several reasons why some patients will not tolerate met pads). Greater relief is obtained by accommodating the rigid ray by letting it drop down. The more flexible remaining rays have a chance now to become stable before the rigid ray gets overloaded. This is acheived by slip-lasted soles, internal layers of cushioning designed to accommodate as well as cushion, or actually grinding out a shallow divot in the shoe and/or liner. A very shallow met pad or internal met bar, in combination with these elements often works. Internal met bars are different shaped met pads.
Grinding wells to accommodate pressure points involves careful marking and grinding of the shoe, and also works nicely for cases of sesamoiditis, especially in rigid cavus or supinated feet, where the 1st ray is often very rigid and heavily plantarflexed.
The key in deciding what to do depends largely on your hands-on assessment of which met heads are plantarflexed and rigid, versus which are merely “dropped” and still flexible.
Orthotics, Arch Supports:
These devices have the ability to determine the initial directions of weight bearing which are critical to most foot related problems. For example, if a hyperpronator unlocks the mid-tarsal arch.
MTP Capsulitis/ Bursitis/ O.A. and Transverse metatarsal nerve irritations
These conditions are often labelled as metatarsalgia, as they occur at the most distal end of the met heads and the metatarsophalangeal joints, usually on the plantar surface.
Reducing the amount of bend at the MTP joint line with proper footwear prescription/modification is a critical aspect to treating these problems, as they are more distal to the major weight bearing part of the met heads. These conditions are related to not only weight bearing, but the constant subluxing of the MTP joints from the millions of repeated extensions we put them through (hammer toes are created by much the same process).
Although X-rays will indicate osteoarthritis, distinguishing between a bursitis and a capsulitis under the MTP joint line is very difficult. Fortunately, the treatment principles are the same.
** The above information is not intended to replace a physicians advice. Seek a physicians advice first.