Bone-like metal improving joint-replacement outcomes

Implants made from Trabecular Metal, a special bone-like metal with high-fixation and weight-bearing capacity, are changing the face of joint-replacement surgeries in India. Rhythma Kaul writes.

Implants made from Trabecular Metal, a special bone-like metal with high-fixation and weight-bearing capacity, are changing the face of joint-replacement surgeries in India.

“It is closest to the natural bone in terms of flexibility and load-bearing capacity,” said Dr Ashok Rajgopal, chairman, Bone and Joint Institute at Gurgaon’s Medanta Hospital, at the launch of the TM implant for hip joint in the 6th Joint Replacement State of the Art Conference in Panaji, Goa .

“It’s a cement-less option where bone grows into the implant within merely six to eight weeks after the surgery. Earlier, it would take up to six months or may not grow at all,” he added.

“It’s technically more advanced as the coating at the back helps the implant fix well,” said Sean F O’Hara, managing director, Zimmer (Shanghai) medical international trading co. Ltd., the manufacturerers of the implant.

Three people have received TM implants for hip replacement in India - one at the All India Institute of Medical Sciences (AIIMS) and two in Medanta. For knee replacement surgeries in India, the metal has been used successfully for almost four years.

Options such as this one benefits patients needing bone grafts as India’s only bone bank at AIIMS has received only 32 cadaver bone donations since 2001. .

“Apart from longer shelf life, there are also less infection issues and failure rates with the metal,” said Dr Suri Narayanan, senior orthopaedician, Chennai’s Apollo Hospital.

“It is proving to be a boon for a section of patients. We have nearly stopped using allograft (transplant oftissue from one individual to another of the same species with a different genotype) for socketsbecause there are hardly any available, but for the thigh bone we still don’t have an option,” said Dr Rajesh Malhotra, professor, department of orthopaedics, AIIMS.

However, this wonder metal cannot be used for all patients. “It is not something that everybody would use on everybody, but it’s a great bailout option for patients who are on the verge of losing the bone and young patients in whom we would otherwise prefer delaying revision surgery,” added Dr Narayanan. Since most people in India seek treatment at a late stage when the joint or bone has degenerated and there are not too many options left to save it.

Severe arthritis, hip fractures, tuberculosis, steroid and heavy alcohol consumption leads to rapid bone loss and are common reasons for joint replacement surgeries.

Each TM hip implant costs about 1.2 lakh, which is about 30% higher than the conventional implants.