Brachymetatarsia with accessory navicular in right foot: A rare coincidental finding

Aetiology, diagnosis, and treatment of brachymetatarsia: a narrative review

Brachymetatarsia (BM), or hypoplastic metatarsal, is an abnormal shortening of one or more metatarsal bones with a female-to-male ratio of 10.53:1. Different causes are described in the literature, such as congenital, acquired, or iatrogenic, associated with different conditions and syndromes. Its presence may develop deformity and pain; however, often feet are pain free and the major worries of patients are cosmetics. Non-operative treatments aim to improve the comfort of metatarsal heads and the possible dorsal conflict through comfortable shoes or the use of specific orthotics. The surgical treatment is anything but straightforward, with "one-stage" or "two stage" techniques, the latter better called "by gradual distraction". One-stage procedures are more rapid techniques but have limited ability to restore the desired length due to neurovascular compromise caused by acute lengthening. Insufficient correction is also possible. On the contrary, by gradual distraction procedures allow gradual distraction lengthening of more than 1.5 cm, but require the use of an external fixator, with a higher risk of complications in more than about 50% of surgeries. The adjacent metatarsal shortening should be considered in combination with other techniques, to diminish the excessive lengthening. In each case, surgeries should be always decided on each patient's concerns, deformities, and clinical needs.

Brachymetacarpia and brachymetatarsia: do we need to operate?

Brachymetacarpia and brachymetatarsia are rare congenital presentations denoted by shortening of metacarpals and metatarsals respectively, in which the deformity usually presents around childhood/early adolescence.

The aetiology is usually congenital besides several other syndromic or endocrinologic associations.

Cosmetic issues such as absence of a normal-looking knuckle while making a fist or disruption of finger-tip curvature besides functional issues are the main indications for surgical intervention in brachymetacarpia.

In the foot, apart from cosmetic issues, pain due to transfer metatarsalgia as well as callosities along with toe deformities which lead to difficulty of using footwear are the main indications for intervention.

Lengthening of the affected bone, either acute with grafting or gradual, is the mainstay of treatment. Gradual lengthening can be either single-stage as in callotasis, or two-stage where the primary procedure is followed by bone grafting after the length has been achieved.

Adolescence, specifically between 12 and 15 years, is the preferred period for surgical intervention in these cases.

Cite this article: EFORT Open Rev 2021;6:15-23. DOI: 10.1302/2058-5241.6.200087