Do Custom 3D-printed Revision Acetabular Implants Provide Enough Value to Justify the Additional Costs? The Health-economic Comparison of a New Porous 3D-printed Hip Implant for Revision Arthroplasty of Paprosky Type 3B Acetabular Defects and Its...

Purpose: Total hip arthroplasty (THA) is a common operation for patients suffering from hip arthrosis. It has been proven effective in improving quality of life while being cost-effective. Meanwhile, the number of revision hip arthroplasty is growing and those may require bone reconstruction and are potential indications for 3D custom implants. In these specific indications, medical 3D-printing has grown over the years and the use of 3D-printed implants has become more frequent. To date, the cost-effectiveness of 3D-printed implants for acetabular revision THA has not been evaluated. Therefore we performed a health economic analysis to: (1) analyse the cost-effectiveness of the aMace implant compared to its closest alternative on the market, (2) have a better insight into Belgian costs of revision hip arthroplasties and (3) estimate the budget impact in Belgium.

Hypothesis: 3D-printed acetabular implants provide good value-for-health in Paprosky type 3B defects in a Belgian setting.

Material And Methods: Custom Three-flanged Acetabular Components (CTAC) were compared to a 3D-printed implant (aMace) by means of a Markov model with four states (successful, re-revision, resection and dead). The cycle length was set at 6 months with a 10-year time horizon. Data was obtained through systematic literature search and provided by a large social security agency. The analysis was performed from a societal perspective. All amounts are displayed in 2019 euros. Discount rates were applied for future cost (3%) and QALY (1.5%) estimates.

Results: Revision hip arthroplasty has an average societal cost of €9950 without implant. Based on the outcomes of our model, aMace provides an excellent value for money compared to CTAC. The Incremental Cost-Effectiveness Ratio (ICER) was negative for all age groups. The base case of a 65 year old person, showed a QALY gain of 0.05 with a cost reduction of €1265 compared to CTAC. The advantage of using aMace was found to be greater if a patient is younger. The re-revision rates of both CTAC and aMace and the utility of successful revision have the highest impact on costs and effects. A Monte Carlo simulation showed aMace to be a cost-effective strategy in 90% of simulations for younger patients and in 88% of simulations for patients above 85 years old. In Belgium it would imply a cost reduction of €20500 on an annual basis.

Conclusions: Based on the findings of this model, the new 3D-printed aMace implant has the potential to bring an excellent value for money when used in revision arthroplasty of Paprosky type 3B acetabular defects. For all patients, aMace resulted in a dominant, cost-saving strategy in Belgium compared to CTAC.

Level Of Evidence: III, comparative medico economical diagnostic tool.