It is a procedure that involves removing a tumor (usually malignant or benign aggressive) of the upper leg bone (femur) and in most instances replacing the bone and hip joint with a special customizable proximal femur tumor prosthesis.
The hip consists of your femur and pelvis. The pelvis is composed of three parts; the ischium, ilium, and pubis. The socket (hip joint) is called the acetabulum which forms the “cup.” The proximal (upper portion) femur and its diaphysis (middle portion) are common sites for primary bone sarcomas and metastatic tumors. Some of these tumors include osteosarcomas, chondrosarcomas, and Ewing’s sarcomas. Limb-sparing surgery can be performed for approximately 95% of tumors arising from the upper femur. In some instances, the extremity cannot be saved and an amputation is performed.
Contraindications for saving the limb may include neurovascular invasion, infection, pathological fracture, invasion of the pelvis, extensive disease, contamination from a poorly performed biopsy, recurrent disease.
A long incision is made over the first two-thirds of the leg to ensure that the entirety of the tumor is removed.
Developing surgical planes (margins that are tumor free) and separating muscles that can be preserved such as the vastus lateralis and leaving those in continuity with the tumor that should be removed such as part of the gluteus maximus. This is based on preoperative MRI and intraoperative findings as well as the type of tumor.
In rare cases a nerve (s) may need to be removed if it is involved by the bone sarcoma. For this procedure it is vital that the femoral (femur bone) artery and veins and sciatic nerve are properly identified. Once the blood vessels and nerves are properly identified they can be retracted (moved away) and protected throughout the procedure.
Once nerves such as the sciatic nerve are tagged and protected and muscles are retracted exposing the tumor, the tumor can be taken out with the upper femur bone.
The inner bone is drilled into in order to fit the largest possible hip prosthesis.
This femur prosthesis is sized and built during the surgical procedure then implanted. We cement the prosthesis into your bone and safely secure it in place.
Reconstruction of the upper leg/hip utilizing a specialized tumor prosthesis is the most common limb-sparing technique for bone sarcomas, soft-tissue sarcomas, or large benign aggressive tumors that have destroyed the bone arising in this area. This prosthesis is sized and built during the surgical procedure then implanted and secured in place using cement. The length of bone removed is based on preoperative X-rays and MRI.
The gluteus medius muscle is attached to the prosthesis to ensure proper functioning post-surgically.
Multiple muscle rotation flaps are used to restore function and stability of the elbow as best as possible. The goal is to provide a stable hip so the extremity can function well. Soft-tissue reconstruction that involves rotating and reattaching the surrounding muscles, including the vastus lateralis, iliopsoas, and gluteus medius. Restoring the function of the surrounding muscles and hip joint is most important for achieving optimal functional outcomes and for protecting the prosthesis from infection.
We then close your incision with sutures and cover the surgical site with bandages. Multiple large drains may also be used to drain the surgical site and prevent a seroma (buildup of fluid).
This is an x-ray of the femur prior to surgery. The tumor is located on in the entirety of the femur bone seen in the photo.
This is an x-ray of a patient after the surgical placement of the prosthesis and removal of upper femur.
This is an MRI of the tumor located in the right femur (left side of the image). In comparison to the healthy bone on the left femur, there is a darkened tumor in the upper third of the right femur.
This is an image of a patient going through a proximal femur replacement. An incision was made in the skin and was pulled back to reveal the muscular tissue, veins, arteries, and nerves.
This is an image of the femur bone after the muscles are separated and the femur is out of the hip socket.
This is an image of the diseased bone after being removed from the femur.
The specimen is placed next to the prosthesis to ensure that the length of the prosthesis matches the resected femur length.
The prosthesis is then inserted into the remaining femur bone and fit back into the hip socket.
This is an image of the prosthesis fully fitted back into the hip socket.
Soft tissue is fixed over the prosthesis to ensure proper functioning post-surgically.
After your surgery you will spend a few nights in the hospital and then will be recuperating at home. Various pain protocols and nerve blocks are used to minimize pain. Mostly all patients are very comfortable after the surgery. For the first few days you will ice the area and keep it elevated to reduce swelling. You will return to the office 2 weeks after surgery. Patients are usually kept in a hip abductor brace for 6 weeks to allow the surrounding muscles to heal and prevent dislocation of the hip by stabilizing the prosthesis. Once cleared, you will subsequently start physical therapy. We usually prescribe specific physical therapy protocols 3 times a week for 12 weeks after surgery to gradually strengthen muscles. Strengthening with significant resistance after sufficient range of motion is achieved as determined by Dr. Wittig. There may be an ultimate weight limit imposed upon you depending on various factors.
You will be monitored periodically with X-rays over the course of 5 years. Sometimes an MRI and/or CT may be used to additionally monitor the area to make sure the tumor has not come back. You will then have follow up appointments every 4 months for the first 2 years, then every 6 months for the next 2 years, and then once a year. Since the bone integrity has been restored to full or almost full, recovery is anticipated provided the patient adheres to strict physical therapy.