the use of three-dimensional printing in orthopaedics: a systematic review and meta-analysis

Objectives: 3d-printing is a rapidly developing technology with applications in orthopaedics including pre-operative planning, intraoperative guides, design of patient specific instruments and prosthetics, and education. existing literature demonstrates that in the surgical trea tment of a wide range of orthopaedic pathology, using 3d printing shows favourable outcomes. despite this evidence 3d printing is not routinely used in orthopaedic practice. we aim to evaluate the advantages of 3d printing in orthopaedic surgery to demonstrate its widespread applications throughout the field.methods: we performed a comprehensive systematic review and meta-analysis. amed, embase, emcare, hmic, psycinfo, pubmed, bni, cinahl and medline databases were searched using healthcare databases advanced search (hdas) platform. the search was conducted to include papers published before 8th november 2020. clinical trials, journal articles, randomised control trials and case series were included across any area of orthopaedic surgery. the primary outcomes measured were operation time, blood loss, fluoroscopy time, bone fusion time and length of hospital stay.results: a total of 65 studies met the inclusion criteria and were reviewed, and 15 were suitable for the metaanalysis, producing a data set of 609 patients. the use of 3d printing in any of its recognised applications across orthopaedic surgery showed an overall reduction in operative time (smd = -1.30; 95%ci: -1.73, -0.87), reduction in intraoperative blood loss (smd = -1.58; 95%ci: -2.16, -1.00) and reduction in intraoperative fluoroscopy time (smd = -1.86; 95%ci: -2.60, -1.12). there was no significant difference in length of hospital stay or in bone fusion time post-operatively.conclusion: the use of 3d printing in orthopaedics leads to an improvement in primary outcome measures showing reduced operative time, intraoperative blood loss and number of times fluoroscopy is used. with its wide-reaching applications and as the technology improves, 3d printing could become a valuable addition to an orthopaedic surgeon’s toolbox. level of evidence: i