Limb Salvage Surgery and Modular Endoprostheses for Bone Cancers

Limb Salvage Surgery can now be offered to almost 90% of the patients detected to have bone cancer. This has been possible due to the advent of modular endoprostheses, improvement in surgical techniques, diagnostic modalities, better chemotherapy drugs and regimes and our better understanding of bone cancers.

Limb Salvage Surgeries require meticulous pre-operative planning and requires the orthopaedic Oncosurgeon to discuss the case in a multi-disciplinary setting and cancer centre having all the requisite supporting units. A well-trained and experienced Musculo-Skeletal Radiologist, Vascular surgery team, Plastic surgery support besides the Orthopaedic Oncosurgeon form the core team for undertaking such procedures.

Parts of Limb Salvage Surgeries

Limb Salvage Surgeries mainly involve 2 parts – Resection and Reconstruction. Resection involves taking out the tumour bearing bone out of the body safely by keeping a margin/cuff of normal tissue around it, so that no tumour is left behind. Reconstruction involves replacing the bone/ joint which has been resected out with metal prosthesis or other biological methods.

These metal prostheses are called endoprostheses or megaprostheses and are made of special metals/ alloys such as cobalt-chromium, stainless steel or titanium.  These metal prostheses are available readily, light-weight yet extremely strong at the same time and are modular.

Since one size doesn’t fit all, modular endoprostheses means that various size and shape options are available for adjusting according to the size of the joint and length of bone which have been resected out. Endoprostheses allow patients to bear weight on them in case of lower limb reconstructions almost immediately after the surgery. Patients can resume activities like walking, climbing stairs and other routine activities after 2- 3weeks post-surgery with these modular endoprostheses.

Nowadays, lower limb endoprostheses with rotating platforms are available for reconstruction in resection of bone tumours around the knee joint, where the knee joint has to be replaced. Also, hydroxyapatite coated collars for endoprostheses stems are available which allow bone integration and overgrowth around the metal stem- bone interface.

All these recent advancements in metallurgy and their designs have increased the longevity of these modular endoprostheses, thereby decreasing various complications which were seen earlier with these prostheses.