An unnamed surgeon attached to the Port-of-Spain General Hospital in Trinidad has objected to performing any hemiarthroplasty or hip replacement surgeries with mismatched implants he believes are being supplied for the procedures. He says the practice could cause other serious health issues for patients in future.

A report in today’s Trinidad Guardian newspaper suggests that a letter was submitted by the surgeon to medical director Dr. Anthony Parkinson indicating that the practice endangers patients lives.

The Guardian article explains that the surgeon learned of the situation by accident when he was about to perform a hip replacement surgery on a patient on February 26. He said prior to the surgery the representative of the company supplying the components contacted him to indicate there were minor deficiencies in the size of the two major components required for the procedure.

The surgeon said he thought the situation to be workable and proceeded with the operation. However, in his letter of complaint to Parkinson, he wrote: “During the operation, I noticed different colour coding on the two components.”

He said upon closer look he discovered the supplier did not supply the two major components – a femoral stem and a bipolar component – from the same manufacturer, as international best practice dictates.

He produced photos he took of the packaging to show the femoral stem was manufactured by Smith and Nephew while the bipolar component into which the stem is supposed to fit was manufactured by Kalyx India Healthcare.

Smith & Nephew is a 150-year-old British-based multi-national medical equipment manufacturing company which specialises in orthopaedic reconstruction. Its products are FDA-approved and used globally. Meanwhile, Kalyx India Health Care, according to one business directory, was incorporated in 2003 and is based in Chennai. Their website,, contained no information about their products or services and only had its address and contact number.

The surgeon wrote to his superiors indicating the practice of mixing components was an indefensible case of malpractice.

“Mixing components from different manufacturers is unacceptable and may be a cause of catastrophic implant failure, medico-legally lead to a completely indefensible case of malpractice/negligence,” he argued.

The surgeon explained that because manufacturers use different alloys a mismatch of materials can causes corrosion at the point of contact, which leads to the failure of the prosthesis.

His professional opinion is also supported by research globally.

Professor of Materials Engineering at the University of Dayton Douglas Hansen, in an article titled “Metal Corrosion in the Human Body,” advised that the mixing of the materials stainless steel and cobalt chromium alloys, which are key components of the mismatched implants currently being used at the PoSGH, should be avoided.

According to the local surgeon, who also kept the packaging as evidence, the mismatched components (the femoral stem) contains steel and (the bipolar component) cobalt-chrome.

“I would prefer not to use any bipolar hip replacement implants from this supplier until the issue is addressed,” the surgeon concluded in his letter to Parkinson.

The Trinidad Guardian said it contacted the North West Regional Health Authority on the issue yesterday under whose aegis the Port-of-Spain General Hospital lies and learnt that the matter was being investigated.