What is Poland Syndrome?
Poland syndrome is a condition that can cause several different problems with the body’s anatomy. One of the key issues includes the absence or underdevelopment of a muscle in the chest called the sternocostal head of the pectoralis major. Other potential problems can include a lack or small size of a muscle called the pectoralis minor and abnormalities of the fingers such as syndactyly, which is when two or more fingers are fused together.
The syndrome can also result in the absence or underdevelopment of the same-side breast, changes to the shape of the chest (known as excavatum deformities), and a lack of rib development. The issues typically only affect one side of the body and more commonly occur on the right side. But in very rare cases, they can affect both sides of the body.
There are many different ways that Poland syndrome can manifest itself, ranging from a slight underdevelopment of the pectoralis major muscle to serious underdevelopment of the chest wall. Likewise, the abnormalities to the upper limbs can vary from mild fusion of the fingers to severe shortening of the fingers (brachysyndactyly).
What Causes Poland Syndrome?
The cause of Poland syndrome, a disorder characterized by an underdeveloped chest muscle on one side of the body, is not completely known. It is believed to be related to problems with certain blood vessels, specifically the subclavian arteries (major blood vessels in the upper chest), and their branch vessels. These issues arise during the early development of the embryo (the stage when a baby is forming in the womb), resulting in reduced blood flow to the affected side of the chest wall.
This theory is supported by findings that the subclavian arteries and branch vessels appear underdeveloped in people with Poland syndrome, indicating that poor blood flow to the developing arm bud (the part of the embryo that forms the arm) during early development could be the cause of the syndrome.
In addition to these factors, there is evidence to suggest that harmful substances could also contribute to Poland syndrome. Smoking or cocaine use by the mother during pregnancy has been linked to the condition. Furthermore, certain medications, such as misoprostol (a drug used to treat ulcers, induce labor, or terminate pregnancy), have been associated with the syndrome.
Risk Factors and Frequency for Poland Syndrome
Poland syndrome is a condition that impacts around 1 in 36,000 to 50,000 newborns, and it’s found more often in males than in females. It’s also noted that the right side of the body tends to be more affected in males. Most instances of this condition occur randomly, although there have been a few cases reported within families. Because Poland syndrome may often go undiagnosed and unreported, we can’t say for sure how common it actually is, and we can only make an educated guess about its regular occurrence rate.
Signs and Symptoms of Poland Syndrome
Poland syndrome is usually identified by physical imperfections that primarily concern a person’s appearance. It typically does not come with any symptoms. However, children and severe cases may require a more thorough examination. The condition is sometimes associated with lung herniation and an unusual placement of the heart towards the right side (dextroposition), so patients will need to disclose any history of heart or lung complaints.
A physical examination for Poland syndrome includes checking the chest and extremities for physical abnormalities. The front of the chest is evaluated, feeling for any unevenness in muscles, and checking for bone or cartilage deformities in the rib cage. The doctor will look for absence or underdevelopment of chest muscles and examine the thinness of chest tissues. Oftentimes, underdevelopment or absence of the nipple can be seen, as well as thinning hair in the chest and underarm.
- Evaluation of the front chest wall
- Checking for asymmetry in chest muscles
- Examination of bone and cartilage deformities in the rib cage
- Inspection for absent or underdeveloped chest muscles
- Assessment of the thinness of chest tissues
- Inspection for absence or underdevelopment of the nipple
- Checking for thinning of hair in the chest and underarm areas
In women, differences in breast size and underdevelopment, including a higher placement of the breast on the affected side, are also common. It’s necessary to evaluate the size of the muscles in the back, as underdevelopment can also occur. A heart and lung examination is recommended, particularly in cases where Poland Syndrome affects the left side. Furthermore, a visual assessment and physical examination of the same-side limbs can reveal abnormalities, such as fusion of any fingers (syndactyly), underdevelopment of hand bones, and anomalies of the index, middle, and ring fingers.
- Inspection for breast asymmetry and underdevelopment
- Evaluation of back muscles
- Heart and lung examination
- Visual inspection and physical examination of the same-side limbs
For pediatric patients, the condition is often associated with Klippel-Feil syndrome and Mobius syndrome. In these cases, a physical examination to check for abnormalities in the neck vertebrae and facial anomalies should also be carried out.
Testing for Poland Syndrome
Ultrasounds before birth can show signs of issues such as one-sided limb problems and unevenness in the chest wall. If these problems are spotted, it’s important to then look for any other related health issues. Once a person is grown, usually a doctor can diagnose Poland syndrome just by examining the person physically. But sometimes additional tests may be needed. For instance, a CT scan, which is a kind of detailed x-ray, can be helpful if the person is planning to have surgery or if they need to be checked for heart or lung problems, including a condition where the lung pushes out of its normal position.
A mammogram, which is an x-ray of the breast, can often show problems such as an underdeveloped breast or a smaller than normal pectoralis major muscle, one of the muscles in the chest. There may also be signs of Poland syndrome on a chest x-ray, such as one lung area looking too bright. An ultrasound of the chest wall can also be useful to check the pectoralis major and minor muscles (these are the two muscles that make up the chest).
Treatment Options for Poland Syndrome
Very rarely, surgery might be needed to address conditions related to Poland syndrome. This might be necessary when there’s unusual movement in the chest wall, underdevelopment or absence of a female breast, or if there’s a noticeable difference in the size of the two sides of the chest in men and women.
Reconstructive surgery is also an option when there’s severe underdevelopment or absence of the ribs. The type of surgery and the steps taken can vary depending on the extent of the irregularity and the age and gender of the patient. Common surgical approaches might include using a muscle flap (transplanting muscle tissue from one part of the body to another) and breast enhancement in women.
Bone grafts (transplants of bone tissue) can be used when the breastbone and ribs are affected. In cases where the latissimus dorsi muscle (a large muscle in the back) on the affected side is underdeveloped, surgeons might use the corresponding muscle from the other side of the body.
For children with fused fingers (a condition called syndactyly), a surgical procedure to separate the fingers is usually straightforward and can be performed with or without a skin graft. This operation usually doesn’t cause significant complications.
Physical therapy can be beneficial for young children with Poland syndrome to help them adapt to their physical differences, and learn how to crawl and move. After surgery, physical and occupational therapy can also be very helpful in the recovery process and to adapt to any changes in the body’s abilities or appearance.
What else can Poland Syndrome be?
In women, Poland syndrome can sometimes be mistaken for simple unevenness in breast size. Additional tests, like a CT scan, can assist doctors in differentiating between this normal asymmetry and Poland syndrome by looking at the structure of the primary chest muscle, pectoralis major.
Also, if a CT scan unexpectedly shows that the pectoralis muscle is missing, it might not necessarily indicate Poland syndrome. The muscle could also be absent due to a surgical procedure.
Similarly, if an x-ray incidentally shows unusually bright (or “hyperluscent”) lung area on one side, a number of conditions could be to blame:
- Blocked airway
- Swyer-James syndrome (a rare lung disorder)
- Having had a mastectomy (surgical removal of one or both breasts)
- A large, one-sided lung bubble (bulla)
- Pneumothorax (collapsed lung)
Possible Complications When Diagnosed with Poland Syndrome
Most people with Poland syndrome don’t have symptoms and don’t experience many functional issues. How well a person with this syndrome will do over time typically depends on how severe their symptoms are and how much surgery they’ve needed. The types of complications they might have are usually the same ones that people have after similar types of surgeries for other reasons.
What to Expect:
- Most people with Poland syndrome don’t have symptoms
- The future health of a person with this syndrome usually depends on symptom severity and amount of surgery
- Complications are typically similar to those after other types of surgeries
