What is Distal Humerus Reconstruction with Allograft?
Distal humerus reconstruction with allograft is a surgical treatment option for a severe distal humerus fracture of the elbow where there is significant bone loss. The surgical treatment involves the replacement of the damaged sections of the distal humerus with an osteoarticular or osteochondral allograft to restore normal function of the elbow and/or arm. An osteochondral or osteoarticular allograft is a piece of tissue containing bone and cartilage that is obtained from a deceased donor or tissue bank to replace lost bone and cartilage tissue that can occur with a severe distal humerus fracture. The allograft tissue is shaped to precisely fit the defect in the distal humerus of the patient and then transplanted to repair the damage.
Anatomy of the Elbow
The elbow joint is made up of 3 bones: the humerus (upper arm bone), radius (forearm bone on the thumb side), and ulna (forearm bone on the pinky side). The distal (lower) end of the humerus bone in the upper arm joins with the radius and ulna bones in the forearm to form the elbow joint. The elbow joint is very important for the movement of your arms and for the coordination of daily activities. Any injury or fracture in the distal humerus can cause significant impairment in the function of the elbow joint and the arm.
Indications for Distal Humerus Reconstruction with Allograft
Distal humerus reconstruction with allograft is usually indicated for a severe distal humerus fracture that cannot be treated with conservative treatment such as medications, rest, or corticosteroid injections. A distal humerus fracture may result from a fall. This can occur when you land directly on your elbow during a fall, or when you get struck by a hard object. It can also happen when you fall on your outstretched arm with the elbow locked straight. Distal humerus fractures are usually very painful. The common symptoms are swelling, bruising, stiffness, tenderness, severe pain, and inability to move the arm.
Preparation for Distal Humerus Reconstruction with Allograft
Preoperative preparation for distal humerus reconstruction with allograft may involve the following steps:
- A review of your medical history and a physical examination is performed by your doctor to check for any medical issues that need to be addressed prior to surgery.
- Diagnostic tests such as routine blood work can help detect any abnormalities that could compromise the safety of the procedure, and imaging such as CT and MRI scans provide a detailed evaluation of the bones and soft tissues of the distal humerus.
- You will be asked if you have allergies to medications, anaesthesia, or latex.
- You should disclose any current medications or supplements taken or any current illnesses or conditions you have such as heart or lung disease.
- You may be asked to stop taking certain medications, such as blood thinners or anti-inflammatories, or other supplements for a week or two.
- You should refrain from alcohol and tobacco at least a few days prior to surgery and several weeks after, as they can hinder the healing process.
- You should not consume any solids or liquids at least 8 hours prior to surgery.
- You should arrange for someone to drive you home after surgery.
- A signed informed consent form will be obtained from you after the pros and cons of the surgery have been explained.
Procedure for Distal Humerus Reconstruction with Allograft
Distal humeral reconstruction with allograft is usually performed through an open incision, under general or spinal anesthesia. An incision is made to expose the defect in the distal humerus. The size of the defect is then measured, and a portion of the cartilage and underlying bone is removed. A fresh allograft taken from a deceased donor is sterilized, prepared in the laboratory, and tested for risk of disease transmission. It is then trimmed with an oscillating saw to match the size of the defect. The allograft is then gently press-fit into the area of defect in the distal humerus. It can be further stabilized with metallic screws and pins as needed. The incision is then closed and a dressing is applied.
In general, distal humerus reconstruction with allograft involves the following steps:
- Your surgeon makes an incision over the elbow joint and cuts through the soft tissues in order to gain access to the area of defect in the distal humerus.
- Retractors are used to hold the tissue apart so the surgeon can view the damage in the distal humerus.
- Your surgeon then performs debridement of the distal humerus to remove damaged cartilage and bone. Care is taken to prevent damage to adjacent healthy cartilage and bone tissue.
- A thoroughly prepared fresh or frozen osteoarticular or osteochondral allograft is then transplanted into the area of the distal humerus defect and allowed to grow.
- Your surgeon may also use pins, plates, or screws to secure the allograft in place.
- Intraoperative fluoroscopy is performed by your surgeon to confirm satisfactory repair and proper placement of the graft.
- Finally, the incision is closed and covered with a bandage.
Postoperative Care Instructions and Recovery
In general, postoperative care instructions and recovery after distal humerus reconstruction with allograft involves the following steps:
- You will be transferred to the recovery area where your nurse will closely observe you for any allergic/anesthetic reactions and monitor your vital signs as you recover from the effects of anesthesia.
- You are advised to move around in bed and walk as frequently as possible to prevent the risk of blood clots.
- You may notice some pain, swelling, and discomfort in the elbow area. Pain and anti-inflammatory medications are provided as needed to address these. You may also apply ice packs to the treatment area to help reduce swelling and pain.
- Antibiotics may also be prescribed to address the risk of surgery-related infection.
- Your arm may be secured with assistive devices such as a hinged elbow brace with your elbow bent at 90 degrees for the first weeks to facilitate healing.
- Instructions on incision site care and bathing will be provided to keep the wound clean and dry.
- You are advised to refrain from strenuous activities and lifting heavy weights on the operated arm for at least 6 months. A gradual increase in activities is recommended with your physician’s guidance.
- An individualized physical therapy regimen will be designed to help strengthen your elbow muscles and optimize elbow function once you are off the elbow brace.
- You should be able to perform your normal daily routines in a month or two; however, a return to sports may take 6 months or longer.
- You should refrain from driving until you are fully fit and receive your doctor’s consent.
- A periodic follow-up appointment will be scheduled to monitor your progress.
Risks and Complications
Distal humerus reconstruction with allograft is a relatively safe procedure; however, as with any surgery, some risks and complications may occur, such as:
- Damage to surrounding structures
- Poor bone healing or nonunion
- Failure of the graft
- The need for re-operation
- Adverse reactions to anesthesia