At first there is tenderness over the metatarsal heads. This may be described by the patient as “walking with a pebble in the shoe.” Ultimately, a callus forms over the second or third metatarsal head, yvhich is itself painful, and aggravates the irritation by increasing the weight bearing upon the metatarsal head.
The tenderness is noted by the examiner squeezing the metatarsal head between the thumb and index finger. The examiner must compress each metatarsal head individually and must not compress the tissues between the heads. This space contains ligaments and the interdigital nerves and can confuse the examiner.
Metatarsalgia is common in the middle aged who have a pronation tendency and most common after a weight gain. This combination and increasing sedentary existence, increases symptomatology. Internal tibial torsion or knock-knees can increase the pronation of the foot. A “toe-out” gait increases pronation.
The pronated foot is a loose packed articular forefoot in that all the joints are incongruous and the articulations widened to permit the foot to splay (spread). This also permits the transverse metatarsal head arch to float. This causes a wider print of the wet foot upon absorbing paper, as the arch depresses in the same manner as flatfoot.
As the foot everts, from whatever causes the anterior tibialis muscle that inverts (supinates), the foot is less efficient. The toe extensors now are in direct alignment of the foot and function more to dorsiflex the foot. This further everts the foot, and simultaneously dorsiflexes (extends) the proximal phalanges. The extended proximal phalanx further exposes the metatarsal heads to excessive depression and weight bearing.
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