Acute simultaneous correction of 4th and 5th brachymetatarsia: A case report

Brachymetatarsia results from the premature closure of growth plates, leading to the development of an abnormally short metatarsal. This is typically congenital. The incidence is estimated to be between 0.02 % to 0.05 %. When evaluating cases involving more than one metatarsal, the combination of the first and fourth metatarsals is more common. The presentation of fourth and fifth brachymetatarsia is extremely rare. This case report serves as the first to discuss the acute correction of the fourth and fifth brachymetatarsia simultaneously.

A 15-year-old male patient presented with bilateral pain in the fourth sub-metatarsal region, accompanied by shortening and dorsal lateral aspect involvement of bilateral fourth digits. Sport activities worsened his symptoms, especially to the right fifth digit. Clinical, biomechanical, and radiographic evaluations were conducted. A plantar crease was observed bilaterally at the fourth sub-metatarsal region, along with varus deformity of the fifth digit and an elevated fourth digit.

Radiographically, a notable shortening of the fourth and fifth rays was observed in the metatarsal parabola, measuring 16.5 mm and 18.5 mm, respectively. The joint space appeared congruent, and a moderate plantar bowing of the fifth metatarsal was evident on lateral view. The patient underwent acute correction of the fourth and fifth metatarsals. Additionally, the patient underwent tendon lengthening and capsulotomies utilizing two separate incisions.

The patient experienced a successful recovery without complications, achieving complete relief of symptoms within a year. Two commonly utilized correction techniques include gradual lengthening with an external fixator and single-stage lengthening using a graft. In this case, the patient underwent single-stage lengthening, and post-operative serial radiographs demonstrated the full incorporation of the grafts.

Level of clinical evidence: IV