A medical device that was intended to replace a patient’s jaw had “inherent defects” and caused increased pain, nerve damage and limited jaw movement, according to a statement of claim lodged in the county court of Victoria.
Guardian Australia has previously reported that two other patients whose jaw pain was treated with the Maxoniq OMX TMJ prosthesis device alleged in separate cases filed to Victoria’s county court that they suffered life-changing injury, loss, and damage due to complications after their surgeries. In those cases, the patients are taking legal action against maxillofacial surgeon Dr George Dimitroulis, a company director of Maxoniq and who also oversaw their treatment. Dimitroulis is defending the claims.
In a third case, a patient, Celina*, had her right temporomandibular joint replaced with the OMX TMJ device in September 2017 . The temporomandibular joint, known as the TMJ, connects the jaw to the skull, with one on each side of the head.
One year later, Celina also had her left TMJ replaced with the same device, the statement of claim filed to the county court in July says. The goal of both surgeries was to replace her damaged joints with a durable device that would restore jaw function and reduce joint pain.
Celina is now suing Maxoniq Pty Ltd, which manufactured the OMX TMJ device, in a case filed by law firm Arnold Thomas & Becker. Celina alleges in her statement of claim that neither of the devices were fit for purpose. They were not durable, they were not free from defects and they were not as safe as would be expected by a reasonable consumer, it is alleged.
“The failure defects, and the risk of adverse events were inherent in the OMX replacement system,” the statement of claim alleges.
Maxoniq denies the OMX device was subject to “inherent defects” and says the claim fails to account for significant pre-existing conditions, including chronic inflammation and degenerative bone disease.
In 2020 Celina underwent revision surgery where it became clear one of the screws in one of the devices had come loose, it is alleged. All four of the screws across both devices were replaced during that surgery.
A scan taken one month later revealed three of the four replacement screws had since fractured.
Maxoniq says the screws are not an inherent part of the OMX device and the choice of screw length or type is at the surgeon’s discretion.
A further revision surgery was ordered and took place in 2021 with a different surgeon, who discovered two of the replacement screws had come loose. Both OMX devices were removed by this surgeon and replaced with a different brand of device, the statement of claim says.
Celina, now aged 37, alleges that as a result of the OMX device allegedly not being of acceptable quality, the original surgeries to implant it and the surgeries required to address the device defects, she suffers more pain in her jaw and face, nerve damage, a speech impediment including a lisp and has limited range of motion when she opens her mouth.
“At the time of the first OMX joint surgery, the plaintiff was employed,” the statement of claim says. “She required time off work as a result of the poor results from the first and second OMX joint surgery and the revision surgeries. She makes a claim for past and future loss of earnings.”
A statement on the Maxoniq website says: “The prosthesis is designed to replace a non-functional TMJ, restoring function, reducing pain and ultimately improving the patient’s quality of life”.
The statement of claim says on 16 June 2021, medical regulator the Therapeutic Goods Administration issued a recall action notice against Maxoniq for the OMX device due to the issues with the screws.
Maxoniq claims the OMX device was not recalled. Instead the company notified the TGA itself and a hazard alert notice was issued in relation to two components.
A defence filed to the court on 30 August on behalf of Maxoniq states that the surgical screws in question “do not form part of the OMX replacement system”.
The choice of screw length, type and manufacturer of screws is at the “surgeon’s discretion, and so does not comprise an inherent part of the OMX replacement system,” the defence document says.
The failures of the device described were a result of improper installation or surgical technique and not a defect in the OMX replacement system, the defence alleges.
The defence further states that Maxoniq “provided information and documentation to all surgeons to present to all patients using the OMX replacement system” including information about common risks.
“The failure defect and the risk of adverse events are not inherent to the OMX replacement system,” the defence document states.
Nytia Rajan, associate with Arnold Thomas & Becker, who is representing Celina, said it would be alleged that “as a result of the treatment provided to our client, she has experienced a significant injury in the jaw and face, including nerve damage, limited opening of the mouth, and subsequently a speech impediment”.
All three patients alleging damages due to the device were treated by the same surgeon, Dr George Dimitroulis, who is the founder and a company director of Maxoniq. All were implanted with the same OMX TMJ prosthesis device.
One of the former patients alleged Dimitroulis did not disclose his commercial interest in the company and that this represented a conflict of interest.
In his defence filed to the court in that case, Dimitroulis denied the allegation. He also denies allegations made in the two cases filed to the county court that those patients were not fully informed of the potential risks of the procedure.
His defence in those cases states that patients were adequately advised of the risks and likely results of the procedure, and that “he acted in a manner that was widely accepted in Australia by a significant number of respected practitioners as competent professional practice”.
Dimitroulis has not responded to numerous requests from Guardian Australia for comment.
*Name changed to protect identity due to sensitive medical information
Do you know more? melissa.davey@theguardian.com