What is Humerus Fractures Overview?
The upper part of the arm bone, or humerus, has two parts known as necks. The anatomic neck is an old growth plate, while the surgical neck is the area beneath the round top part of the humerus. Blood is supplied to this area by the anterior and posterior humeral circumflex artery. The axillary nerve is also significant in this area.”
The main part of the humerus is cylindrical in shape but gradually becomes more triangular towards its end. Muscles like the pectoralis major, deltoid, and coracobrachialis are attached here, while muscles like the brachialis, triceps, and brachioradialis originate from here. The major nerve in this area is the radial nerve, located in the spiral groove, 14 cm from the outer bump of the elbow and 20 cm from the inner bump.
The lower part of the humerus, known as the distal humerus, has two main nerves: the ulnar and the radial nerve. Different types of fractures can occur here, including those above the elbow, single bump fractures, fractures involving two columns and fractures in a coronal plane. Treatment options vary from open or closed reduction (setting the bone back in place), fixing the bone internally, pinning, and use of a rod inside the bone or a brace.
What Causes Humerus Fractures Overview?
Humerus fractures, or breaks in the upper arm bone, usually happen due to injury or because of weakened bones from a disease that has spread to the bone. Injuries that cause these fractures can be from high-energy accidents like falls or car crashes, or low-energy injuries such as trip-and-fall accidents.
Risk Factors and Frequency for Humerus Fractures Overview
The humerus is a bone in your upper arm, and fractures here can make up anywhere between 4% and 6% of all bone breaks. Additionally, between 1% and 3% of all fractures are specifically in the proximal humerus, which is the top part of this bone. These injuries can happen to anyone, but they occur in certain situations more often than others. For example, younger men usually get these fractures from severe accidents. On the other hand, older women often get them after falling from standing height.
There’s another interesting fact about these fractures. In patients with multiple injuries, a fracture in the shaft of the humerus is a sign that the person might also have injuries inside their abdomen, fractures in their long bones, or fractures in their hands. So, doctors pay extra attention to these cases.
How these injuries affect a person can vary by age. Younger people typically have a temporary disability, while older people can experience a permanent disability.
- Humerus and proximal humerus fractures account for 4%-6% and 1%-3% of all fractures, respectively.
- These fractures occur usually due to high-energy trauma in young men.
- In older women, these fractures are usually after a ground-level fall.
- In patients with multiple injuries, a humerus shaft fracture can indicate other serious injuries.
- While these injuries usually result in temporary disability in young individuals, they can lead to permanent disability in the elderly.
Signs and Symptoms of Humerus Fractures Overview
If you injure your arm and go see a doctor, there are a few things they might notice during a physical examination. These include the arm being red, pain when trying to lift the arm, and the need to use the other arm for support. It’s very important for the doctor to check the nerves and blood flow both before and after repositioning a dislocated joint or bone (called reduction) to make sure no additional damage was done during this process. Sometimes, to readjust a fractured bone, the patient’s arm is placed in its natural position and the pull of gravity is used to assist the procedure.
Testing for Humerus Fractures Overview
If a fracture in the upper part of the arm bone (the proximal humerus) is suspected, certain views from x-rays are recommended. These are commonly known as true AP, scapular Y, and axillary views. Sometimes, in preparation for surgery or if there’s uncertainty about the position of the bone pieces or the larger bump near the top of the arm bone (the greater tuberosity), a CT scan may be performed.
In cases where a fracture in the shaft, or the long, straight section of the arm bone is suspected, x-rays from the front (AP view) and from the side (lateral view) that include the joints above and below the suspected fracture area would typically be part of the initial check-up.
When a fracture around the lower part of the arm bone near the elbow (the distal humerus) is suspected, it’s customary to take x-rays from the front (AP view) and from the side (lateral view) of the arm and elbow, which should span the entire arm and forearm.
Treatment Options for Humerus Fractures Overview
For proximal humerus fractures or ones near the shoulder, if the fracture is minor or the patient isn’t a good fit for surgery, it’s usually managed with a sling and gradual physical therapy. For moderately displaced fractures, a process called closed reduction and percutaneous pinning, where the doctor maneuvers the bone fragments back into place and uses pins to hold them, is used. Open surgery may be indicated for larger displacements and split fractures, especially in younger patients. Rod insertion can be suitable for certain fractured parts or combined fractures in younger patients. In elderly patients or in cases where surgery isn’t feasible, half a shoulder replacement can also be an option.
A total shoulder replacement is performed if the glenoid surface, or shoulder socket, is damaged. A reverse total shoulder replacement may be indicated in cases where the rotator cuff doesn’t function properly or for elderly people with reconstructable tuberosities, which are the bony bumps on your shoulder.
Traditionally, humerus shaft fractures or breaks in the upper arm bone are treated non-surgically since the bone isn’t weight-bearing and being slightly out of alignment may still lead to good results. This treatment typically involves a Sarmiento brace. The brace allows the joints above and below the fracture to move, minimizing stiffness, and can be removed to allow for better underarm hygiene. Those who might not be good candidates for non-surgical treatment include those with severe soft tissue or bone damage, vascular injury requiring repair, or brachial plexus injury.
Open surgery may be needed when it comes to open fractures, vascular or brachial plexus injury, fractures accompanying a wrist injury, and a condition called compartment syndrome. Other potential reasons include multiple injuries, bilateral humerus fractures, pathological fractures, and cases where bracing can’t be used due to burns or soft tissue injuries.
Intramedullary nailing or inserting a metal rod within the bone can also be a suitable treatment option. It’s usually less invasive and involves shorter surgery time, but may lead to increased shoulder dysfunction, pain at the entry site, and a rotational deformity.
How fractures near the elbow are treated typically depends on the type of fracture. Cast immobilization can be used for Milch type I fractures, pinning or surgical reduction for displaced Milch Type I fractures, while fractures on the upper part of the lower arm or involving both sides of the elbow usually need open surgery. Total elbow replacement may be advised for elderly patients with fractures involving both sides of the lower arm.
What else can Humerus Fractures Overview be?
When you get hurt and it involves your upper arm area, like your shoulder or elbow, doctors have to consider several injuries that could have occurred. You may have broken a bone, such as your elbow, collarbone (also known as the clavicle) or the shoulder blade (known as the scapula). Another possibility is that your shoulder could be dislocated, which means the upper arm bone has been pushed out of the shoulder socket. These are medical emergencies which require immediate attention.
What to expect with Humerus Fractures Overview
Fractures of the upper part and main body of the humerus (arm bone) usually have good results, with a high rate of successful healing and a low chance of infection. This holds true whether they’re treated with or without surgery. However, fractures of the lower part of the humerus tend not to fare as well. Roughly 75% of patients are able to regain movement and strength in their elbow, with the objective of achieving a range of motion between 30 and 130 degrees.
Possible Complications When Diagnosed with Humerus Fractures Overview
Damage to the radial nerve, which can cause loss of movement or sensation in the arm, is a known risk associated with fractures of the humerus bone in the arm. This can happen during the initial injury, during open surgery to set the bone, or during a procedure where a metal rod is inserted into the bone for support. In closed fractures, where the skin is not broken, radial nerve damage is often caused by the nerve being compressed or stretched. But in open fractures, where the skin is broken, it may be due to the nerve being damaged.
The risk of radian nerve damage is higher with fractures towards the end of the humerus because the radial nerve runs close to the bone in this area. In cases of a closed fracture, damage to the radial nerve is not a reason to opt for open surgery to fix the bone and explore the nerve. In fact, many patients regain their nerve functionality without any specific treatment within 3 to 6 months. However, if no improvement is seen in 3 to 4 months, an electromyogram (EMG) – a test to evaluate the health of muscles and the nerves that control them – should be performed.
Surgical exploration is recommended if the fracture was open, if a closed fracture shows no improvement in nerve function over 3 to 6 months, or if an EMG identifies muscle activity associated with nerve damage at the 3 to 4 month mark.
