What is Phocomelia?

Phocomelia is a rare birth defect where there are missing parts of the arms or legs. In children with phocomelia, the hands or feet are connected directly to the body. This condition became well-known due to its link with a medication called “thalidomide”. Initially, this drug was used to alleviate anxiety and morning sickness. However, it was found to cause phocomelia and was pulled off the market in the 1960s.

About 40% of the infants affected by thalidomide did not survive birth. The birth defects caused by this drug had major effects on society and politics, resulting in tighter regulations and need for proof of safety for drugs.

What Causes Phocomelia?

Phocomelia, a condition where arms or legs are unusually short or absent, is known to be a significant side effect of a drug called thalidomide. In the past 30 years, there have been several instances of phocomelia linked to the use of thalidomide. However, these days, the cause of most cases isn’t known. Even with strict rules around the world, there are still cases of phocomelia due to thalidomide popping up.

Such incidents are reported mostly in less developed countries and places where leprosy is common, and thalidomide is occasionally still being used. These places still report cases of birth defects due to exposure to thalidomide during pregnancy. On the bright side, in more developed countries with strict regulations, there has been a significant decrease in instances of phocomelia in the general public.

Besides being linked to the drug thalidomide, some researchers believe that phocomelia can be caused by unusual development of the subclavian artery, which is a significant blood vessel in the body. This abnormal development can disrupt the blood supply to the limbs, which in turn could lead to phocomelia.

Risk Factors and Frequency for Phocomelia

A study by Bermejo-Sanchez and his team looked into 22,740,933 live births to understand the prevalence of a condition called phocomelia. They found that out of every 100,000 babies born, roughly 0.62 will have this condition. Around half of these cases had phocomelia on its own, while 36.9% of the babies had other major birth defects too. In 9.9% of cases, this condition was associated with a clinical syndrome.

More than half of the cases (55.9%) only affected one limb.
40.2% of cases impacted two limbs.
There were only four instances (out of 141) where all four limbs were affected.
When only one upper limb was affected, it was more commonly the left one (64.9% of cases).

When two limbs were affected, they were more often the upper limbs (58.5% of cases), as compared to the lower ones. This is lower than what earlier studies had reported. The reason could be that this study was specifically looking at cases of true phocomelia and excluded conditions like amelia or other types of limb shortening.

Signs and Symptoms of Phocomelia

Phocomelia is a condition that can be present in newborns, often linked to the use of a drug called thalidomide. When phocomelia is identified, it’s important to ask about any medications taken during early pregnancy. In addition, these children should be thoroughly checked for other health problems. This is backed by research, which shows that over a third of kids born with phocomelia also have other major health issues, and nearly 10% have symptoms associated with different syndromes.

Testing for Phocomelia

If a child is diagnosed with phocomelia, a condition where the arms or legs are unusually short or missing, doctors should conduct a detailed check for any other abnormalities. This is because nearly half of the patients with this condition also have other physical issues. Especially, doctors should examine the child’s musculoskeletal system, which includes the bones and muscles, the intestines, and the heart. Issues with these organs are often seen alongside phocomelia.

Treatment Options for Phocomelia

If a child is born with phocomelia, a condition in which the limbs are underdeveloped, it’s crucial to check for other health problems, specifically with the heart and intestines. Experts in children’s heart and gut health should inspect the child and suggest a plan of action for any found health issues.

In terms of the underdeveloped limb, artificial devices may help, but many kids without additional health issues can manage sufficiently. Families of these kids should collaborate with therapists to better understand how to satisfy their child’s special needs.

Lastly, caring for a child with a disability can be quite distressing for some individuals. Thus, doctors should be ready to suggest mental health support services to aid the parents and the child in coping with their situation.

A study by Bermejo-Sanchez and colleagues found that nearly 10% of individuals with phocomelia, a condition characterized by the absence or defect of an arm or leg, also have other associated syndromes. These conditions, listed based on their decreasing prevalence, include:

Roberts Syndrome: This is a rare condition that is passed down in families (autosomal recessive) resulting from a mutation in the ESCO2 gene. People with this syndrome typically have severe deformities in their arms and legs, and facial abnormalities.
Thrombocytopenia with radial aplasia, also known as TAR: This is another rare, autosomal recessive condition. It is associated with the RBM8A gene. People affected by TAR typically have a low platelet count, which can lead to excessive bleeding. They often have a deficiency in the radius, one of the main bones in the forearm.
Syndrome of severe limb defects, vertebral hypersegmentation, and mirror polydactyly: This autosomal recessive condition causes severe underdevelopment or absence of the arms and legs, extra fingers or toes (polydactyly), and too many segments in the spine (hypersegmentation).

These conditions are all rare genetic disorders, highlighting the complexity of diagnosing and treating individuals with phocomelia.

What to expect with Phocomelia

A particular study examined the birth outcomes for children with a condition called phocomelia, which is a birth defect that affects the arms or legs. The study found that for every 85 children with phocomelia who were born alive, there were 24 who were stillborn, meaning they died in the womb.

However, when the researchers looked specifically at cases where the child had phocomelia but no other health problems, the numbers were different. In these situations, for every 57 children who were born alive, there were eight who were stillborn.

Possible Complications When Diagnosed with Phocomelia

Phocomelia, a condition where children are born with poorly developed limbs, has a higher rate of stillbirth in comparison to the general population. Moreover, kids with severe underdevelopment of the limbs could have difficulties with daily activities and movements. Consequently, healthcare teams need to be comprehensive and cater not only to the medical needs but also to the day-to-day challenges that come with phocomelia.

Possible Challenges for Children with Phocomelia:

Higher risk of stillbirth
Severe underdevelopment of the limbs
Difficulties with daily activities
Mobility issues

Healthcare for Children with Phocomelia should include:

Medical treatments
Support for daily activities
Assistance with mobility needs

Preventing Phocomelia

There’s been a big decrease in cases of limb abnormalities caused by the drug thalidomide because of stronger drug regulation worldwide. Thalidomide is a medication that can help with sleeping problems, anxiety, and even treat a disease called leprosy. However, it’s especially important for women who are pregnant, or might become pregnant, to know about the potential dangers of taking thalidomide during early pregnancy. Both patients and doctors need to be aware of the harmful effects of thalidomide when it’s taken early in pregnancy.