Skeletal Limb Abnormalities
Skeletal limb abnormalities are problems in the bone structure of your arms or legs. Your arms and legs are commonly known as limbs.
Skeletal limb abnormalities can affect one part of your limb or the entire limb. Usually these problems are present when you are born. Sometimes babies are born with abnormalities in more than one limb.
Certain diseases or injuries can disturb the normal growth of your bone structure and can lead to skeletal abnormalities.
Types of Skeletal Limb Abnormalities
A congenital skeletal abnormality is present when you are born. The abnormality may mean that one of your limbs is smaller or larger than normal or that you have more fingers or toes than normal. You could also be missing an entire arm or leg, or you might be missing a segment of one of your limbs or have fingers and toes that might not be completely separated from each other.
The abnormalities can happen because of a chromosome problem.
In some cases, congenital limb abnormalities can result from the mother taking prescription drugs during pregnancy.
Congenital limb abnormalities are rare. In the United States, approximately 1,500 babies are born with skeletal abnormalities in their arms. About half as many newborn babies have skeletal abnormalities in their legs (CDC).
An acquired abnormality is one that happens after your birth. Such a condition occurs when you were born with normal limbs but experienced a bone fracture during childhood. The broken bone might grow more slowly than usual. This could lead your affected arm or leg to develop abnormally.
Some diseases, such as rickets and rheumatoid arthritis, can negatively affect your bone structure. These diseases lead to abnormalities in your legs or arms.
Causes of Skeletal Limb Abnormalities
Currently, the causes of congenital skeletal limb abnormalities are not fully understood. Some possible risk factors for this condition may include:
- being exposed to viruses, medications, or chemicals before birth
- tobacco use by your mother while she was pregnant with you
- having other kinds of abnormalities. These include omphalocele, a heart defect, or gastroschisis.
- congenital constriction band syndrome, in which bands of amniotic tissue get tangled in your arms or legs before your birth
Acquired limb abnormalities can be caused by a childhood injury. Some of these injuries result in slower bone growth. They can also be caused by a number of diseases that affect your bone structure. These include:
- rickets, or vitamin D deficiency
- Marfan syndrome, a connective tissue disorder
- Down syndrome, a genetic disorder involving extra chromosomes
What Are the Symptoms of Skeletal Limb Abnormalities?
If you are born with a skeletal limb abnormality, the outward symptoms can be obvious, such as:
- a limb that is not fully formed or is missing a component
- one leg or arm that is shorter than the other
- legs or arms that are not in proportion with the rest of your body
In the case of acquired limb abnormalities, you might not have any external symptoms. Some common signs of an acquired limb abnormality are:
- one leg appears to be shorter than the other leg
- pain in your hip, knee, ankle, or back
- one shoulder looks slumped in comparison to the other
- unusual walking gait such as a limp, rotating your leg in an unusual way, or walking on your toes
How Do Doctors Diagnose Skeletal Limb Abnormalities?
If the abnormality is present when you are born, it can usually be diagnosed immediately. A diagnosis is formed based on a physical examination.
An acquired skeletal abnormality requires a fairly extensive examination. This procedure includes viewing your medical history, taking a physical exam, and measuring your limbs.
Other diagnostic procedures allow doctors to determine any type of skeletal limb abnormality. X-rays, CT scans, or other types of medical imaging allow doctors to view your underlying bone structure.
What Treatments Are Available?
For congenital limb abnormalities, there are three primary goals of treatment. These include encouraging development of the affected limb, improving the appearance of the affected limb, and helping you adapt to day-to-day problems that may be caused by the abnormality.
Your doctor will help you in deciding on the best type of treatment for your specific condition.
Your doctor may prescribe an artificial arm or leg. This limb is known as a prosthetic limb. It functions in place of a normal arm or leg.
In some cases your affected limb is present but weakened. An orthotic brace or splint may be used to support your affected limb so it can function normally.
Occupational or Physical Therapy
In some cases, your doctor may recommend occupational therapy or physical therapy. Therapy helps you to exercise and strengthen your affected limb.
Sometimes surgery is necessary to repair the abnormalities in your leg’s structure. Two types of surgery are epiphysiodesis and femoral shortening. Epiphysiodesis is a carefully timed procedure to stop the normal growth of one leg so that the shorter leg can reach an equal length. Femoral shortening is a procedure in which part of the femur bone is removed.
Sometimes, doctors might recommend that your shorter limb be made longer through a gradual process called limb lengthening. This procedure involves cutting your bone. Doctors then use an external device to gradually increase the length of your leg over the course of several months to a year. This procedure can be painful. It also has a higher potential of complications than other treatment options.
Long-Term Outlook for Skeletal Limb Abnormalities
As a child with a skeletal limb abnormality, you may face a variety of physical and emotional difficulties. Your experience will depend on where the abnormality is located and how severe it is. Some possible issues could include:
- problems with developing motor skills and other physical milestones
- being limited in sports participation or other activities
- being teased or excluded because of differences in your appearance
- needing help in personal activities, such as eating or bathing
Seeking ongoing medical treatment for skeletal limb abnormalities can assist you in gaining optimal functioning and independence. Many people with some type of limb deformity are able to live productive and healthy lives.
Prevention of Skeletal Limb Abnormalities
There is no certain way to prevent skeletal limb abnormalities from occurring. Instead, the focus is on early detection and treatment.
A pregnant woman can decrease chances of limb abnormalities in her baby by taking a prenatal vitamin that includes folic acid. It is also recommended that pregnant women should avoid the use of tobacco and alcohol during pregnancy.