A proximal humerus prosthetic replacement is a procedure that involves removing a tumor, usually malignant or benign aggressive, of the upper arm bone/humerus and in most instances replacing the bone and shoulder with a special customizable proximal humerus tumor prosthesis.
This is a procedure that involves removing a tumor of the upper arm bone, called the humerus. In most instances, the bone and shoulder are replaced with a special customizable prosthesis.
The shoulder girdle consists of the proximal humerus, scapula, and clavicle. Common tumors that affect the upper humerus are various sarcomas, benign aggressive tumors, and metastatic cancers to bone. Some of these tumors include osteosarcomas, chondrosarcomas, and giant cell tumors. Limb-sparing surgery can be performed for approximately 95% of tumors arising from the upper humerus. 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 chest wall, extensive disease, contamination from a poorly performed biopsy, recurrent disease.
The previous biopsy sit is marked and the incision is made leaving a decent margin so that there is no tumor remaining after it is removed. The incision is made from the clavicle and extends down to the biceps.
The muscle groups are released to expose the the humerus bone, and an incision is made that allows the surgeon to be able to pass their finger underneath into the humerus. The muscles that don't have to be removed in the resection of the tumor are marked to ensure that they are used during the reconstruction stage.
This image shows the transection (horizontal cut) of the muscle groups so that the neck of the scapula bone is exposed.
In rare cases a nerve(s) may need to be removed if it is involved by the tumor. Once the blood vessels and nerves are properly identified they can be retracted (moved away) and protected throughout the procedure. In this case, the musculocutaneous nerve may need to be removed, leading to loss of elbow flexion.
There are two different types of resections and reconstructions for bone sarcomas of the proximal humerus based on whether or not the sarcoma extends outside the bone into the soft tissues or if it is entirely encased by the bone. Most of the time it extends into the soft tissues. In these cases, the sarcoma easily spreads across the joint and into the deltoid muscle. The socket (glenoid) and deltoid muscle are removed in these cases (extra-articular resection). If the tumor is contained in the bone, the deltoid and socket can be saved (intra-articular resection).
There are different methods of prosthetic reconstruction in each case. In an extra-articular resection when the deltoid muscle and socket are removed and the scapula body is used as a new socket. The prosthesis is stabilized to it and the clavicle and sutured. In an intra-articular resection, the deltoid muscle is preserved, and special methods are used to stabilize the prosthesis in the socket. The main goal is to restore shoulder stability and have a functional hand and elbow.
Soft-tissue coverage of the prosthesis. We use your surrounding muscles to cover the prosthesis. The soft tissue coverage utilizing your muscle not only provides additional support to your prosthesis, but also helps prevent skin problems and infections after your surgery. The muscles used for this technique can include your deltoid and latissimus dorsi (“lat” muscle).
We 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 tumor in the bone. The tumor is located in the right shoulder (towards the top of the image).
This is an MRI of the tumor. The tumor is located in the right shoulder (top of the image).
This is an x-ray image of the proximal humerus with the endoprosthesis fully inserted.
This is an image of the patient prior to the surgery beginning. The ellipse was where the previous biopsy was performed to confirm the presence of a tumor, and the line is where the incision is going to be made to ensure that the entirety of the tumor is removed.
Here the skin has been folded back to reveal the muscular tissue underneath.
The muscles have been further removed or pulled back to get a full view of the tumor. The white thread is wrapped around the major nerves and arteries to ensure that they are not damaged during the surgery.
Here is an image of the tumor after being fully removed from the arm.
This prosthesis is sized and built during the surgical procedure then implanted. We cement the prosthesis into your bone and safely secure it in place
This is an image of the prosthesis after being fit and cemented into the arm. Tissue will be sutured around the prosthesis to ensure proper functioning post-surgically.
This is an image of the shoulder after the prosthesis is inserted and the soft tissue is reconstructed around the prosthesis.
The wound is fully closed and a catheter is inserted into the wound so that a build-up of fluid won't occur 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 sling for 6 weeks to allow the muscles to heal. The elbow is not permitted to extend beyond 45 degrees of flexion for 4 to 6 weeks to allow the biceps muscle to heal which will stabilize 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.