3D printing of implants and legal liability
Next week is the ECHT conference in Prague. I will give a lecture there on the topic of 3D printing of implants from Ti6Al4V, Center of Excellence. Technically, it seems that the solution is known and if the appropriate 7 million EUR can be found, it can begin.
But implantology has another pitfall that needs to be considered. An interesting article has been published on the topic of implant failure [1]. A bone replacement was printed for a patient after a severe cancer disease on a device such as Arcam, EBM (Electron Beam Melting).
Fig. 1 and 2 – Analyze of the case from [2]
However, this bone substitute cracked after 6 months. The reason was a defective internal structure after printing, incorrect geometry, and high stress. The implant is loaded with low-cyclic fatigue, and considering the above, the substitute did not last. This can happen, even if it should not, but what about compensation for damage?
If it happens on a machine, the part is simply replaced, and you move on. Any claims for defective performance or compensation for damages are handled through the Civil Code using standard processes. But what if it happens to a person?
The patient not only has to be in terrible pain but is also bedridden and immobile again. And a possible re-operation for a new implant brings additional risks, because its location is already affected by the installation of the first implant.
I found out that this is not an unknown topic at all, and many comments can be found on the Internet.
For example, here [2] you can find a view from the USA. The National Library of Medicine has published an analysis of the state of 3D printing with the aim of defining the legal framework for 3D printing for medical purposes. It follows that the principle of fault must be examined throughout the chain, from the powder manufacturer, the printer, to the surgeon who performs the operation.
Fig. 3 – View of responsibility in the USA according to source [2]
The Czech model is seemingly simpler, it does not examine either the source powder for printing or the printer, however, it is considered that both fall within the competence of the printing contractor with all necessary links. Thus, there must be a clear procedure for purchasing, periodic validation of printers, HIP, vacuum ovens and other equipment must be carried out according to the relevant standards and regulations, generally covered by MedAccred certification, ISO 13485, etc.
The division of responsibility between the patient, hospital and implant manufacturer is subject to both civil liability (in particular under the Civil Code and the Health Services Act), and potentially also liability for a defective product under Act No. 89/2012 Coll. (Civil Code) and Act No. 22/1997 Coll. on technical requirements for products.
Implant manufacturer – liability for defective product
The implant ruptured due to:
- Poor design of the shape (design error),
- Incorrect production technology (use of EBM without subsequent HIP/heat treatment),
- Here is a strong basis for the manufacturer’s liability for a defective product according to § 2939 et seq. of the Civil Code:
- If the product (implant) does not meet the safety standards that can be reasonably expected, it is considered defective.
- The manufacturer is liable objectively (i.e. regardless of fault) if the defect causes damage to health (§ 2940 of the Civil Code).
- It is not necessary to prove fault, only that the implant was defective and caused damage.
Conclusion: The manufacturer bears primary liability for a defective product, especially if it could be proven that the technology used was inadequate and standard (e.g. no HIP or heat treatment) – which is commonly required for Ti6Al4V in medicine.
Generally, the warranty period for hidden defects is 2 years, but in the case of patient damage it is 10 years. According to EU 2024/2853 – The limitation period for a claim for compensation for damage caused by a defective product is 10 years from the placing of the product on the market. However, if the injured party could not initiate proceedings within ten years from the dates referred to in paragraph 1 due to the latency of the personal injury, he will lose the right to compensation under this Directive after the expiry of a period of 25 years.
Hospital – liability for product selection and use
The hospital (or the treating physician) could be held jointly liable if:
- the implant was not appropriately indicated,
- the hospital knew or should have known that the manufacturing procedures for the implant were inadequate, mor if care was neglected in informing the patient (e.g. about the experimental nature of the implant or possible risks).
- From the point of view of the Civil Code (§ 2636 et seq.), the hospital may be liable for an incorrect treatment procedure if the implant was not appropriately selected or was selected despite the risks that it should have known about.
- § 2641 Civil Code: A healthcare provider is obliged to proceed with due professional care and in accordance with the rules of science and recognized medical procedures.
- § 2643 Civil Code: If the provider fails to comply with the treatment procedure or neglects to inform the patient, he is liable for damages contractually (§ 2913 Civil Code).
Conclusion: If the hospital selected this implant without checking its certification, approval, quality, and without fully informing the patient, it may bear partial responsibility.
Of course, the patient may also bear some responsibility if he actively violated the treatment regimen.
But there is another circumstance. The hospital prepares the data, the STL file for 3D printing. From the point of view of responsibility and compliance with the MDR and civil law principles, it is therefore necessary to carefully distinguish between the role of the hospital as a “designer” and the manufacturer as a implementer of the device.
The hospital / doctor (supplier of the data, the design – STL file), provides the source data for the construction of the implant (from CT / MRI), and fundamentally influences the shape, thickness, geometry, and therefore the biomechanical properties, e.g. stress concentration.
If the strength check of the design is not performed (e.g. FEA – Finite Element Analysis), the design may be unsuitable from the beginning. The MDR explicitly states that if a medical institution designs a device, it becomes a (co)manufacturer and is subject to similar obligations. MDR (Medical Devices Regulation) – Regulation (EU) 2017/745.
It follows that the hospital may be jointly liable for a design error if it prepares the STL file and this leads to a faulty stress distribution → subsequent mechanical failure of the implant.
And what does the MDR say about custom-made medical devices? According to Article 2(3) of the MDR: “Custom-made medical device” means a device designed on the basis of a written prescription from a qualified professional (e.g. a doctor) who:
- specifies the specific design features of the device,
- is intended exclusively for a specific patient.
Such devices are not subject to certification by a notified body, but the manufacturer must comply with certain obligations, in particular under Article 10(9) and Article 22 of the MDR.
The implant manufacturer must meet the following:
a) Must have a quality management system (QMS), and must be able to:
-
- document the manufacturing process,
- ensure traceability of materials,
- demonstrate that the product complies with the generally applicable safety and performance requirements (GSPR – Annex I MDR)
b) There must also be technical documentation (Annex XIII MDR). For custom-made implants, the so-called simplified technical documentation is sufficient, but it must exist for each product (e.g. description of the design, material, manufacturing method, quality control method, etc.).
c) Manufacturer’s declaration (Declaration)
Each implant must be accompanied by a declaration that:
- it was manufactured exclusively for a specific patient,
- it complies with the requirements of the MDR (to the extent that can be expected for custom-made),
- and that it is intended for a specific specialist (physician) on his written prescription.
Since implants are individual customer products, it is not possible to validate individual pieces, but the manufacturing process.
- Input materials (Ti6Al4V – certification, e.g. according to ISO 5832-3, Implants for surgery — Metallic materials
- Additive technology (SLM/EB-SLM), technological process and link to validation of equipment, printers
- Post-processing (e.g. HIP, heat treatment, surface treatment), validation of process parameters and validation of equipment according to AMS 2750
- Output quality controls (CT scan, microscopy, porosity testing, tensile or impact tests for each platform, etc.)
This means that the manufacturer does not have to validate each specific shape, but must demonstrate that the entire production chain can repeatedly and safely produce devices that meet the MDR requirements, i.e. reliably and reproducibly.
To meet this, it must also be the owner of a manufacturing permit for custom-made implants, i.e. it must be registered as a manufacturer of medical devices with SÚKL (in the Czech Republic),
- It must have a QMS in place (e.g. according to ISO 13485),
- It must be able to demonstrate that its production meets the MDR requirements, including process validation (not necessarily for each specific product),
- It keeps records of each manufactured piece and keeps documentation for 10 years.
If a medical device designs a device, it becomes a (co)manufacturer and is subject to similar obligations. It influences the design of the implant, and therefore its geometry, strength criteria, etc. It is therefore jointly responsible for an error in the design if it prepares the STL file and this leads to a faulty stress distribution → subsequent mechanical failure of the implant.
The same applies here as with heat treatment,
§ 2594
(1) The contractor shall notify the client without undue delay of the unsuitable nature of the item that the client has handed over to him for the performance of the work, or of the order that the client has given him. This does not apply if he could not detect the unsuitableness even after exercising due care.
The implant manufacturer therefore manufactures a medical device to order based on the STL file supplied by the hospital,
- He is responsible for the material properties (porosity, defects, lack of HIP, unsuitable printing conditions),
- If he knows or should have known that the design is unsuitable (e.g. the geometry is not suitable for the load), he is obliged to inform or not to participate in the production.
The implant manufacturer is therefore responsible for the process, but if he prints an unvalidated or unsuitable STL design without retrospective control, he may also share responsibility for the design.
If a hospital designs an individual implant and has it manufactured externally, it can also be considered a manufacturer under the MDR, or at least a “designer” with responsibility for the design.
The responsibility of the one who prints and the one who submits the design is therefore shared, but in a specific case, expert opinion (e.g. biomechanics + metallurgy) will decide.
Contractual relationship
The patient absolutely has no contractual relationship with the implant manufacturer. However, there is a contractual relationship, even if a contract has not been signed, between the patient and the hospital in the form of a so-called implicit contractual relationship according to Section 2636 et seq. of the Civil Code (NOZ):
Health services are provided on the basis of a “health care contract”, which is created by the patient’s admission for treatment. The patient therefore automatically has a contractual relationship with the hospital, which is responsible for the selection of the treatment procedure, the means used and informing the patient. If the hospital has chosen an unsuitable design or implant, it can be sued for breach of contractual obligation (Section 2913 NOZ).
Primarily, the patient can sue the hospital, because he has a contractual relationship with it. However, this does not prevent the assertion of a claim against the implant manufacturer, compensation for damage caused by a defective product according to Section 2939 et seq. of the NOZ (defective product), or according to Act No. 22/1997 Coll. on technical requirements for products, or according to Act No. 378/2007 Coll. (Act on Pharmaceuticals and Medical Devices).
In this case, however, the patient is obliged to prove that the product was defective and caused damage (e.g. by an expert opinion).
The patient therefore has two options. File a lawsuit against the hospital with which he has a contractual relationship, and if compensation for damage is awarded, the hospital can then claim reimbursement from the manufacturer.
Sue the hospital separately and the implant manufacturer separately. In this case, the lawsuit must be carefully constructed to describe the share of guilt of both entities, and at the same time there is evidence that the design and production contributed to the failure, and the patient wants to maximize the chance of successfully recovering compensation.
Patient
The patient bears the burden of proof. However, he is bedridden, in pain, without legal knowledge, often without the ability to communicate properly, has no professional knowledge and does not have access to his medical documentation. The patient is therefore in a very difficult position. This is a well-known problem throughout the EU, and that is why some courts (including Czech courts) have begun to mitigate or shift part of the burden of proof to the care provider in similar cases – especially when it comes to:
- Treatments that go beyond common practice (e.g. individual 3D implants),
- Cases where the patient is at an informational or factual disadvantage,
- Situations where the provider has violated its information or documentation obligation.
However, without an expert (ideally a biomechanic, orthopedist, materials engineer), it is almost impossible to win a court case. The expert must prove:
- that the implant design was inappropriate,
- or that the production technology was defective,
- and that this had a direct impact on the failure and harm to the patient.
In this case, the hospital is obliged under Act 372/2011 Coll. provide a copy of the patient’s medical documentation (upon request), documentation on the implant (e.g. type, production report) can also be requested, and the manufacturer may be asked by the court to submit technical documentation – if sued.
It is therefore worth contacting an experienced lawyer in medical law – because the legal strategy (e.g. choice of defendant, evidentiary proposal, proposal for an expert opinion) is key.
So much for the paragraphs. If I look at it from the perspective of the manufacturer, the one who prints the implants, he should follow the instructions of the customer, i.e. work with the STL file sent by the medical facility or contradict it.
But if he accepts it, he must proceed according to the usual procedures. What does this mean? The current level of knowledge says that a 3D printed product exhibits porosity. This can be a source of future failure. There is only one technology that can correct this defect, and that is HIP. If, contrary to this knowledge, the manufacturer does not apply HIP to eliminate hidden defects, he is exposed to the risk of being penalized in the event of implant failure and proceedings for damages. Just as in the aviation industry, critical parts made of precision casting must undergo HIP for the safety of pilots and passengers, so too must HIP be applied to 3D printing of implants.
If this case arose and I were asked for an expert opinion, this would be the first thing I would investigate.
[2] https://pmc.ncbi.nlm.nih.gov/articles/PMC10145872/
Remaining images Adobe Firefly.
Jiří Stanislav
June 1, 2025
