The humerus is the long bone in the upper arm. The top of the bone is part of the shoulder joint and the bottom is part of the elbow joint. There are a lot of muscles surrounding the humerus bone: the biceps and brachialis muscles in the front and the triceps muscle in the back. There are also nerves, arteries, and veins going up and down along the bone.
The lower end of the humerus bone is called the distal part, or "distal humerus." The distal humerus has cartilage at the end of it, which is part of the upper part of the elbow joint. The other bones that make up the lower part of the elbow joint are the ulna and the radius. There is a large nerve on the inner side of the distal humerus and elbow, called the ulnar nerve. This is the nerve that causes pain and feeling of pins and needles when you hit your "funny bone."
A broken distal humerus causes pain, swelling, and bruising around the elbow. You may also have numbness and tingling in your fingers (especially the little and ring fingers) from injury to the ulnar nerve (funny bone). Sometimes the break goes all the way down to the elbow joint and goes through cartilage that covers the bottom of the distal humerus. Other times the bone breaks far enough above the elbow joint, so the break doesn’t go through cartilage.
Mechanism and Epidemiology
Distal humerus fractures are not very common. A fracture in the distal humerus can happen after a fall (off a bike, or simply tripping and falling on the ground), a direct hit to the area, or a bigger trauma like a car accident.
When you have a fracture of the distal humerus you will have pain, swelling, and bruising of the elbow. You will likely go to an emergency room or urgent care for treatment. The doctor will examine your elbow to check if the nerves and blood vessels are working properly, and to make sure there are no open wounds. Then they will get x-rays of your elbow to see if the bone is broken.
After the doctors have confirmed that you have a break of the distal humerus, they will put your elbow in a plaster splint. If the broken bones are not in the proper place, the doctors may need to "reduce the break" (set the bones in the right place). To do this the doctors will give you some medication so you get a little sleepy and don’t feel as much pain. They will manipulate the bones and gently push them back in the right place, and put your elbow in a splint. The splint keeps the bones in the proper place and stops your elbow from moving so you don’t feel as much pain.
Most distal humerus fractures need surgery. If you are comfortable in the splint, you may be sent home from the emergency room and referred to see an orthopaedic surgeon. When you see the orthopaedic surgeon they will talk to you about your fracture and what treatment it will need.
If your fracture is complicated (for example if it’s broken in a lot of places, or if there is an open wound or bleeding), you may be admitted to the hospital to have surgery sooner.
If your break is very minimal or if you have osteoporosis, your fracture might be treated without surgery. If that’s the case, you will be treated in a splint or cast.
However, most distal humerus fractures need surgery. The surgery is usually done by making a cut at the back of the elbow and finding the bone. The broken bones are then put back in the right place and are fixed with metal plates and screws. The wound is closed with sutures or staples. You will probably have a splint placed after surgery.
Sometimes if a patient is elderly and the bone is so broken badly that it’s not fixable, it may be better to replace the elbow instead of fixing the bones. This is an option for older patients; younger patients rarely undergo an elbow replacement. Your surgeon will talk to you about the risk and benefits of fixing the bone or replacing it.
After surgery, you will probably have a splint put on your elbow for a while, to let your wound heal. Your surgeon will see you for follow-up 1-2 weeks after surgery.
In the clinic your splint will be removed and you may have x-rays taken of your elbow. The sutures or staples are usually taken out about 2 weeks after surgery. Your surgeon will let you know when it’s safe to start moving the elbow and how much you can lift with your arm. In general, most patients will be given instructions to start moving the elbow at the time of the first postoperative visit. You should also be given instructions about general usage of your arm. For example, shortly after surgery, your surgeon may tell you that you can lift light things, like a cup of coffee, right away, but not lift heavier objects. Your surgeon may also recomment physiotherapy to make sure you are moving your elbow and it doesn’t get stiff.
If your fracture was treated with metal plates and screws, you can return to your normal activities once the bone has healed. But if you were treated with an elbow replacement, you should not lift more than 5-10 pounds with that arm for the rest of your life.
Most patients who have a fracture of the distal humerus are able to return to their activities after a few months. You may have some pain and weakness at the beginning, but this generally gets better with time.
Most people have some stiffness in the elbow after the bone has healed. Stiffness means that you may not be able to fully straighten or bend the elbow all the way, like the other elbow that was not injured.
It is also possible to have some numbness or tingling in the fingers for a few months after surgery, especially the little and ring fingers. There is also a chance you may get arthritis in your elbow, either shortly after the injury or many years later.
If your fracture is treated with an elbow replacement, you typically have an elbow that will function well. However, there is a risk of the metal components getting loose or "wearing out" over the longer term. If this occurs there is a chance you may need more surgery.
Niloofar Dehghan, MD, FRCSC
Edited by the OTA Patient Education Committee and Steven Papp, MD (section lead)
All x-rays and pictures taken from the personal collection of Dr. Dehghan and Christopher Domes, MD