He loved walking and the mountains. Today he struggles to stay standing. In his house near Epinal, Marc Bohyn ruminates. It was in 2023 that he observed a lump forming under his skin, at the level of the groin fold, “like a bump which gets bigger with effort and which can hurt”, he remembers. A “small hernia” is diagnosed and an operation is quickly scheduled. An “ordinary” journey: in France, each year, nearly 250,000 people have abdominal hernia surgery.
“It’s really a routine, everyday surgery,” says this recently retired resuscitation anesthetist. As for 97% of patients operated on for a hernia of the groin, a prosthesis made of synthetic material is implanted to contain his organs. “I myself put a lot of people to sleep for this procedure. I told myself that I would be in the operating room at 7:30 a.m. and that by 10:15 a.m. it would be over.” But waking up is painful, and the months and years that follow even more. "It's a difficult feeling to describe: I feel like my groin is twisting, it's burning inside, it's like I have something too much, it's pushing and it hurts." The pain sets in, 24 hours a day and gradually moves towards the testicles: "like when you receive a violent blow to your private parts. Men know very well what this corresponds to".
No position relieves it. Impossible to sit still for more than thirty minutes to read one of the works in its voluminous library or to have lunch with friends. No more way to put on pants without leaving them open. “It’s humiliating, every time you get up, to have your pants fall to the floor because the pain is such that it’s not possible to put on clothing that’s a little tight.” His grandchildren? "I try to run away from them. My granddaughter adores me and jumps on me. It's unmanageable." The medications put him to sleep or cause him to hallucinate. Marc Bohyn is today “a man transformed by pain”, says his wife, Catherine. “He withdraws, he no longer communicates, he no longer speaks: I still love him, that’s for sure, but it takes a strong dose of love to continue.”
For him, beyond the pain, feelings of anger and guilt also set in: "how could I, while I am a doctor, be such a fool as to throw myself into this without having taken the slightest information?". Because after the intervention, Marc Bohyn does research. He gradually discovers that he is not alone.
In 2023, a young actor, hopeful of the theater, Arnaud Denis, created a Facebook group (which today has more than 10,000 members) and also testifies to unbearable pain, after the installation of a prosthesis to treat a hernia in the groin.
“Terrible intestinal pressure.” “Testicle turning black.” “Nausea.” “Loss of 17 kilos in three-four months”. Severe chronic fatigue. Over time, Arnaud Denis can no longer eat, move, work, make love or even laugh like before. Pain so terrible that it led him to be euthanized in Belgium on September 22, at the age of 43. “I am suffering too much and I know that there will be no improvement,” he confided to the Radio France investigation unit in the spring. “I made this choice not out of despair, but out of extreme lucidity.” During his funeral, in Paris on October 1, 2026, patients, some of whom came from far away, applauded for a long time as his coffin passed by. “Arnaud Denis allowed us to feel less alone and to tell ourselves that these ailments are not in our heads,” testified Coralie, who also considers herself a “victim of hernia prostheses.”
What the actor and whistleblower denounced was a “double level of violence”. “First violence, we don’t warn you enough of the risks,” he explained. Like Marc Bohyn, he was not aware that the operation could go wrong. “The undesirable effects listed in the manufacturers' instructions go in the trash. Nobody reads them,” Arnaud Denis then clarified. “Infection, damage to neighboring organs, migration of the prosthesis, all of that is listed in the instructions. Why didn't my surgeon mention any of these possible complications?” Second level of violence, the actor was indignant, “we shift the responsibility onto the patient”. “Your pain is psychological. Your sexual and digestive problems are psychological. While many patients have no psychiatric history.”
An anger against doctors that he expressed until his last moments: "I am done with medical mistreatment", he wrote on September 22 on his Facebook account, denouncing "abandonment and medical denial in France".
The medical community did not see the distrust of prostheses, most often made of polyester or polypropylene, coming. “We were amazed,” says Hubert Johannet, president of the Academy of Surgery. The installation of a prosthesis is considered “the ideal treatment currently recommended by international learned societies”, recalled several organizations in April 2025, including the French Society of Parietal Surgery – Club Hernie, in a joint press release.
It was not always this way. Since the 1990s, prostheses have gradually replaced the suture method. “Repairing with thread is painful and above all, there is recurrence,” analyzes Alain Valverde, specialist surgeon at the Diaconnesses hospital in Paris. “With the use of prostheses, the idea was to strengthen the abdominal wall by reducing pain and allowing a much faster physical recovery.” “It’s an operation that works so well that I offer it to my patients, my friends, my family,” he adds. "I am a scientist and the data that we have today generally about prostheses is reassuring, adds Professor Pablo Ortega Deballon, they do much more good than harm, that is why we continue to use them. But that does not mean that we deny that there can be side or undesirable effects, explains the surgeon from the Dijon University Hospital. We are aware of this."
The prosthesis, according to French learned societies, is not the heart of the problem. These pains are "inherent to surgical dissection", we can also read in this same press release, published in 2025, and which points, more than prostheses, to damage to the nerves or to the peritoneum, this thin membrane which lines the interior of the abdomen, during the operation. “This pain affects 5 to 10% of patients and is disabling in 1 to 5% of cases,” recognize the doctors. A significant figure given that 2.6 million people have had abdominal hernia surgery in ten years, between 2014 and 2024 in France.
Despite the scientific solidity confidently brandished by surgeons, some have apparently lost their cool in the face of criticism. On LinkedIn, several of them, sometimes great professors, talk about a "media crusade", "unfounded noise" and even insult patients, calling them "anti-prosthetic conspirators" or even "ignorant loudmouths who pour out their ignorance on the internet". Messages which have since been partly deleted.
In consultation, the case of actor Arnaud Denis is sometimes directly mentioned. “The head of department who received me did not examine me. He did not touch me,” says Sarah, director*, for example, to the investigation unit of Radio France. “This surgeon just stayed behind his desk, calling Arnaud Denis crazy,” she testifies. The actor was also brutally insulted, a few days before his death, by a neurosurgeon specializing in the management of chronic pain, who sent him private messages directly on Instagram. “You are weak and a liar.” “It’s a little excessive given the pain I see from being the Calimero who wants to die.” “I can introduce you to young patients who are fighting and who are not complaining on the networks.” “You can kill yourself, why pour out so much hatred.” Arnaud Denis then expressed his anger to a close friend: "I'm being attacked on Instagram."
This neurosurgeon, whom we identified, first assured that she had contacted Arnaud Denis in “an approach of kindness”. Confronted with the violence of her writings, she clarified that he was not her patient and that she had acted in this way, "with a little provocation" to dissuade him from being euthanized. “It may be a huge mistake on my part, but I remain convinced that it is a huge waste because he was not taken care of as he should have,” insists this doctor, who is moving forward, without knowing his medical file, the psychiatric track. “He was in monstrous anger. His fight was the prosthesis, he forgot that his fight was to take care of himself.” A psychiatrization of pain to which many other patients testify.
After the death of Arnaud Denis, the French Society of Parietal Surgery sought to regulate the speeches of doctors, by disseminating advice on its website. “For your patients, we suggest careful and factual wording, without speculation.” What wording? “We learned of this death with great sadness. The situation reported is exceptional.”
The ANSM, the National Agency for the Safety of Medicines and Health Products, has deemed the subject serious enough to put in place “reinforced surveillance” of these medical devices. If it received very few reports between 2020 and 2024, less than thirty per year, their number was multiplied by four in 2025, after the media coverage of Arnaud Denis' testimony. A figure that is still surprisingly low compared to the volume of operations and the known risks. “A statistical anomaly”, estimates public health doctor Pierre-Henri Moury who has just published a study on the subject. "There is a massive gap between scientific data and the feedback given to health authorities," said this doctor, himself a patient. "From that moment on, there is a bias, a truncated perception between what is happening in real life and what is reported to health authorities and ultimately to political decision-makers." How can we then explain this low rate of reports? Surgeons very rarely report adverse effects. "I have not done any because I never thought that it something was happening with the prosthesis", assumes, for example, Professor Pablo Ortega Deballon, in Dijon.
On the patient side, many people explain that they are unable to follow through on their report because they do not know which model of prosthesis was implanted in them. An aberration: providing an implant card, post-operation, is now mandatory. “Victims do not always have this information and seek to recover it by requesting a copy of their medical file,” explains Maître Pierre Debuisson, who has grouped and transmitted hundreds of reports to the ANSM in recent months. But in reality it is a real obstacle course. You have to ask twice, three times, four times for the elements. People end up giving up: it's a perverse system." For this lawyer, the ANSM has a large share of responsibility: "to say that there are few reports when everything is done to limit them as much as possible, that's not honest."
“The ANSM, I often say that it is a silent alarm or a watchdog that never barks”, tackles for his part Maître Philippe Courtois, who has worked in recent years on major health issues: Mediator, PIP prostheses and Dépakine. “Today, for me, there is truly the emergence of a public health scandal,” warns this specialized lawyer, who defends Arnaud Denis and his family, and who filed a complaint with the constitution of a civil party last September, after a first classification without action. “We are on the same wave as the previous scandals: we know that it happens. Let us learn lessons from the past today. And let's do something." Philippe Courtois is currently working on the files of 118 other patients.
Strongly criticized, the ANSM has organized two meetings since last year in the presence of doctors and patients. During these sometimes heated exchanges, to which the Radio France investigation unit had access, the question of the quality of information to patients is central. “It is true that in a preoperative consultation which lasts 15-20 minutes, it is complicated to explain the disease, the surgical technique and to give the fifteen potential complications without gradation”, says for example one of the surgeons present during one of these meetings in June 2025, “there can be very very serious but very very rare complications, (...) a patient cannot remember all the messages that come through the machine gun”. Words that immediately trigger the anger of several patients. “At that point, you can perhaps say to yourself that you will spend 30 minutes in consultation [to inform] instead of 15?”, says Arnaud Denis. “It’s hard to hear,” another man continued.
Poorly informed patients. Badly accompanied. Sometimes denigrated. The Radio France investigation unit also identified cases of patients undergoing surgery when they appeared to have a medical contraindication. “We feel betrayed and terribly alone,” confides Sarah*, the director. The young woman, also suffering, discovered, when reading the instructions for her Versatex prosthesis, a warning for women wanting to have a child: "It is written that 'the surgeon must be attentive to the fact that this product will not stretch sufficiently to adapt to the evolution of the patient's body'". Sarah wants a second child. His surgeon assured him in writing that there would be no problem.
There is also the case of Aïcha*, who had surgery at the age of 15 and whose mother, during a public meeting at the National Assembly last April, cried without being able to stop. "My daughter is 17, she no longer goes to school. She is very ambitious, very intelligent, sporty... She no longer does anything. She no longer has the life of a young girl." On the instructions for his prosthesis, it was also indicated that the placement of an implant was contraindicated on “growing children”. "I feel extremely guilty, because my daughter is a minor. It's
