Patient-Specific 3D-Printed Porous Titanium Implants for Complex Foot and Ankle Reconstruction: Clinical and Radiographic Outcomes - A Current Concepts Review of the Literature.

Abstract

Critical-sized bone defects of the foot and ankle have traditionally been managed with bulk structural allograft or major amputation, both carrying substantial limitations, prompting exploration of patient-specific 3D-printed porous titanium implants as a structural alternative, though supporting evidence remains fragmented. Following the PRISMA 2020 statement and a pre-registered PROSPERO protocol, this current concepts review searched PubMed/MEDLINE, Embase, and the Cochrane Library, identifying 22 clinical studies (4 Level III, 17 Level IV, 1 Level V; published 2015-2026) comprising 289 adult patients undergoing complex foot and ankle reconstruction with these implants; two independent reviewers performed screening, data extraction, and risk-of-bias assessment, with primary outcomes-osseous union, limb salvage, and major amputation-synthesized descriptively as pooled proportions, counting overlapping cohorts once. The pooled limb-salvage rate was 92% (196/214 limbs) and major amputation rate 8% (21/276 patients); among 13 studies reporting a patient-level union endpoint, pooled union was 89% (64/72 patients), with consistent functional improvement and a weighted mean follow-up of 25 months. However, the pooled reoperation rate reached 26% (74/289 patients), driven predominantly by deep infection, with prior ipsilateral infection (odds ratio 14.9) and neuropathy (odds ratio 5.76) as independent predictors; the single comparative study found significantly higher articular fusion and no implant subsidence versus femoral head allograft (p = 0.018 and p = 0.016, respectively). These implants achieve high limb-salvage and union rates with a low major amputation rate, offset by a substantial reoperation burden. Prospective comparative studies with standardized union definitions and longer follow-up are needed. Level V (determined by the lowest level of evidence included).