1.What is limb salvage surgery?

When a person has cancer of the bone in the upper or lower limb, surgery meant amputation of the limb ie. the entire arm or leg would be removed. This led to marked disability and disfigurement. The person also had to suffer psychological social stigma. In order to overcome the functional, psychological and social problems associated with amputation, the concept of limb salvage was evolved. Here, after removal of the tumour bearing bone, the limb is spared.

The aim of limb salvage surgery in bone tumour management is to eradicate the disease, retain the integrity of the skeletal system and preserve a limb with useful function.

2.What are the processes involved in this kind of surgery?

Successful limb sparing procedures consists of 3 phases namely,

Bone resection: After making an accurate assessment of the stage and spread of the tumour the surgeon removes the affected part of the bone.
Reconstruction: The second phase of the procedure involves replacing the removed part of the bone with a graft or an implant (prosthesis). Bone can be grafted from some other part of the patient’s body. Prostheses or implants are made of steel or titanium.

Plastic surgery: This is performed to cover the area with muscle and soft tissues.

3.What is a Custom Made Prosthesis?

Custom: preparing (tailor-made) according to need

Prosthesis: artificial replacement of a part of the body

Implant : a prosthesis placed permanently in the body

Custom made prostheses are implants individually manufactured for each patient to give an accurate fit. The implant is fabricated to fit the patient rather than crafting the patient to fit the implant.

The European Medical devices Regulatory Agency Definition: “Any device specifically made in accordance with a duly qualified medical practitioner’s written prescription which gives, under his responsibility, specific design characteristics and is intended for the sole use of a particular patient.”

4. Are custom made prosthesis available in India?

Previously, they were imported. Today because of the efforts of Prof. Mayil Vahanan Natarajan locally (custom) made mega prostheses are available in Chennai for the past 14 years. They are patented and Custom Mega ProsthesisTM are available for all major anatomic regions of the body. Once a patient is diagnosed with a bone tumour, accurate measurements of the limb are made after radiographic assessment. The implant manufacturer is given the measurements to make a suitable prosthesis. It takes a week to make the prosthesis.

5.How much will they cost?

The cost difference between the locally made prostheses and the imported ones has made a real impact on the bone tumour patients of our country. The imported prosthesis costs up to Rs 5, 00,000 ( US$ 10,000). The local product, Custom Mega ProsthesisTM made from stainless steel, costs only Rs 50, 000.

6.What is an allograft? What is its role in limb salvage surgery?

Allografts are bone taken from another person (alive or cadaver), to be used to replace / reconstruct a part of the body.

7. Will the patient be able to use the limb as before after this operation?

A patient will be able to get good amount of functionality of the limb. The main advantage will be that the cancer is being treated without major disfigurement, and the maximum possible functionality is being restored under the circumstances.

8.What is the age group of patients with bone cancer? Can limb salvage surgery be performed on all these patients?

Patients’ age range is from 10 – 70. Age is one of the factors to be considered, as this is a major surgery and requires some rehabilitation effort on the patient’s part.

If the patient does not have any major medical complications, limb salvage surgery can be performed.

In very young patients who are still growing in height, the operated limb used to remain shorter than the other limb. Now, however, expandable Custom Mega ProsthesisTM are available that can be lengthened according to the growth of the limb.

9. What is the success rate of limb salvage surgery?

The 5 year survival rate with chemotherapy and limb salvage surgery is 70%.

10. What are the complications of Custom Mega Prosthesis?

As with any major surgery, limb salvage by Custom Mega ProsthesisTM has certain complications. The complication rate though is only about 25%.

Complications are grouped as Biological, Mechanical and Oncological.

The Biological complications may be early or delayed infections, skin/flap necrosis and metallosis Mechanical complications include loosening of the prosthesis, prosthesis bending / breakage, prosthesis disassembly and dislocation of the prosthesis. Oncological complications include local recurrence or spread of the cancer to other parts of the body.

These complications can all be managed effectively with the current medical and surgical techniques.

11. What are the recent advances in this area?

Limb salvage surgery is reaching new heights with total replacements of the thigh bone, hip and knee joints. These will give hope to a greater number of bone cancer patients.

The perception that Custom Mega ProsthesisTM can only be used in bone tumour limb salvage surgery to reconstruct large segments of bone,is changing. The field of Custom Mega ProsthesisTM is broad ranging, and incorporates all types of joint replacements such as those in traumatic bone loss, neuropathic joints, reconstructive orthopaedics etc

Nowadays, prostheses are customized with the help of computer assisted measurements to give a more accurate fit. Using titanium alloy (Ti6Al4V) instead of the stainless steel, which is being used at present, will make the prosthesis lighter and stronger.

A Bone Bank has been opened in the new Tower Blocks of the Government General Hospital with the aim to collect, process, sterilize, store and supply bone allografts to all patients in need.