Malunion and nonunion are both problems that occur when a broken bone doesn’t heal correctly.
In a malunion, a bone heals but not in the right position. You may have never had treatment for the broken bone. Or, if you did have treatment, the bone moved before it healed. Malunion symptoms include constant pain long after treatment. If severe enough, the condition can cause a deformity and may require surgery to repair or correct it.
A nonunion is the failure of a broken bone to heal.
Malunion or nonunion injuries are most common in the:
Nonunion can also occur in your:
Malunion and nonunion can cause pain or even some loss of function.
If a malunion affects a nearby joint, it may lead to arthritis because of unusual wear on the joint.
Some people have health problems or habits that cause their bones to fail to heal properly.
Malunion and nonunion risk factors include:
Many things can cause a nonunion, such as:
Request an appointment with a UPMC orthopaedic surgeon:
From UPMC's HealthBeat Blog:
Symptoms of a malunion or nonunion can include constant pain long after your fracture was treated.
Both can cause inflammation or infection because of damage to surrounding tissue.
To make a malunion or nonunion diagnosis, your doctor may need to look at the bone or surrounding tissues using:
If you have a nonunion, your doctor may also run blood or urine tests to look for other issues that may have caused the condition.
Request an appointment with a UPMC orthopaedic surgeon:
The links below will open a new browser window.
UPMC's HealthBeat Blog:
From our Health Library:
Treatment of a malunion often depends on how the injury occurred.
If a bone is misshapen enough to cause a disfigurement, you may need surgery to repair or correct it. Correcting the alignment of the bone is more important if it will cause too much stress on a joint that attaches to that bone.
Treatment of a nonunion depends on what caused it to happen.
Nonunion treatments are limited, but include:
Your doctor might suggest taking anti-inflammation medicine to control any swelling from a malunion or nonunion.
You may also need antibiotics, if you have an infection.
Request an appointment with a UPMC orthopaedic surgeon:
The links below will open a new browser window.
UPMC's HealthBeat Blog:
From our Health Library:
UPMC Patient Ed: