Well, I Didn't See That Coming

A prospective radiographic review by Seif El Masry et al. examined 44 patients who underwent a minimally invasive bunionectomy (MIB) and found that the midfoot width increased as a result of the surgery. The overall midshaft bone width had an average increase of 4.22 mm (5.27%) following MIB. 

Measuring width

Bone and soft tissue widths were measured at distal and proximal locations on weight-bearing anteroposterior (AP) foot x-rays. The intraclass correlation coefficients indicated high interobserver reliability.

How can a distal osteotomy widen the foot proximally?

There was no correlation of proximal width with changes in hallux valgus angle or intermetatarsal angle. This led the authors to conjecture that the MIB technique increased midfoot width through TMT subluxation or hyperadduction of the proximal metatarsal fragment.