Background: Morton's interdigital neuroma (MN) is a common compression neuropathy of an interdigital nerve in the foot. We present retrospective treatment outcomes with a novel modification of the de Prado technique for distal minimally invasive metatarsal osteotomy (DMMO).

Methods: We retrospectively reviewed 25 consecutive patients (25 neuromas) with MRI- or US-confirmed MN who underwent DMMO of only the 4th metatarsal with deep transverse intermetatarsal ligament release with a minimum one-year follow-up after the failure of non-operative treatment. Patient-reported outcome measures (PROMs) were assessed using the Visual Analog Scale (VAS) and the Foot Function Index (FFI). Statistical analysis was performed to assess for differences among sub-groups.

Results: A significant decrease is reported post-operatively in all PROMs evaluated. Pre- and post-intervention mean VAS scores were 7.35 and 0.41, respectively (p < 0.001). Pre- and post-intervention FFI Total scores were 57.5 and 17.2, respectively (p < 0.001). All pre- and post-intervention FFI sub-scores were found to be significantly reduced (P < 0.001). There was one case of prolonged serous (non-infected) drainage, which resolved by three weeks postoperatively.

Conclusions: The data presented demonstrates that our novel operative technique significantly improved patient-reported outcomes irrespective of initial neuroma size, patient sex, or comorbidities. Methods: IV.