Impacted bone allograft personalised by a novel 3D printed customization kit produces high surgical accuracy in medial opening wedge high tibial osteotomy: a pilot study

Applications and accuracy of 3D-printed surgical guides in traumatology and orthopaedic surgery: A systematic review and meta-analysis

Background

Patient-Specific Surgical Guides (PSSGs) are advocated for reducing radiation exposure, operation time and enhancing precision in surgery. However, existing accuracy assessments are limited to specific surgeries, leaving uncertainties about variations in accuracy across different anatomical sites, three-dimensional (3D) printing technologies and manufacturers (traditional vs. printed at the point of care). This study aimed to evaluate PSSGs accuracy in traumatology and orthopaedic surgery, considering anatomical regions, printing methods and manufacturers.

Methods

A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Studies were eligible if they (1) assessed the accuracy of PSSGs by comparing preoperative planning and postoperative results in at least two different planes (2) used either computer tomography or magnetic resonance imaging (3) covered the field of orthopaedic surgery or traumatology and (4) were available in English or German language. The 'Quality Assessment Tool for Quantitative Studies' was used for methodological quality assessment. Descriptive statistics, including mean, standard deviation, and ranges, are presented. A random effects meta-analysis was performed to determine the pooled mean absolute deviation between preoperative plan and postoperative result for each anatomic region (shoulder, hip, spine, and knee).

Results

Of 4212 initially eligible studies, 33 were included in the final analysis (8 for shoulder, 5 for hip, 5 for spine, 14 for knee and 1 for trauma). Pooled mean deviation (95% confidence interval) for total knee arthroplasty (TKA), total shoulder arthroplasty (TSA), total hip arthroplasty (THA) and spine surgery (pedicle screw placement during spondylodesis) were 1.82° (1.48, 2.15), 2.52° (1.9, 3.13), 3.49° (3.04, 3.93) and 2.67° (1.64, 3.69), respectively. Accuracy varied between TKA and THA and between TKA and TSA.

Conclusion

Accuracy of PSSGs depends on the type of surgery but averages around 2-3° deviation from the plan. The use of PSSGs might be considered for selected complex cases.

Level of Evidence

Level 3 (meta-analysis including Level 3 studies).

Comparative study of biomodels manufactured using 3D printing techniques for surgical planning and medical training

OBJECTIVES

To obtain 3D printed bone models with a haptic sensation similar to that of the real bone, which will help the surgeon to learn and improve based on practice.

METHODS

From computed tomography, 3 digital anatomical models of the human proximal femur were created and, by modifying the printing parameters, both cortical and trabecular tissues were simulated, which were combined in a different cortico-cancellous interface depending on the bone segment. The 3 equivalent models obtained were compared with a commercial Sawbone synthetic model and subjected to a series of blind surgical practice trials performed by 5 TOC specialists from a hospital, each of them with different degrees of expertise. A statistical analysis of the qualitative data collected based on the Wilcoxon test, the Spearman correlation matrix, and the Validity Ratio Coefficient was performed.

RESULTS

The deviations observed in the dimensional study are less than 0.2 millimeter, which confirms the validity of the 3DP-FFF technology to geometrically recreate personalized biomodels with high anatomical precision.

CONCLUSIONS

The reproductions obtained have given rise to a reliable method that professionals can refine to plan operations with the consequent reduction of time and risks for the patient, as well as for medical training.