What's Intercostal Neuritis and How to Reduce It
Some women have chest pain similar to intercostal neuritis during pregnancy. This is a rare condition that usually occurs late in pregnancy. However, we don’t know the main cause of this disorder yet, which makes it difficult to treat with certainty.
In this article we will focus on what information is available so far and what are the possible sources of the development of this neuropathy. Likewise, we will try to review what treatment options exist for intercostal neuritis in pregnancy and what are its risks.
Intercostal neuritis of pregnancy as its own entity
There is a dilemma regarding the name of the condition. Intercostal neuritis causes an inflammatory process involving a thoracic nerve that triggers pain. However, in pregnancy, the mechanism involved is not inflammation.
That’s why some authors have proposed that the name that should be used for this disorder is “thoracic neuralgia gravidarum”. The reasons are twofold:
- First, a difference is established with traditional neuritis, the cause of which is well known.
- On the other hand, it’s emphasized that it’s a condition that occurs in pregnant women.
What is known about the origin of chest pain in pregnancy?
As it is a rare condition, studies are scarce. So far, the real cause of chest pain in pregnancy has not been established.
However, there are several hypotheses that attempt to explain the predisposition of pregnant women to develop intercostal neuritis. Let’s analyze them.
Pain due to elongation of the fibers
One of these theories is that the growing uterus produces the progressive elongation of the nerve fibers. This results in the activation of pain receptors, generating the condition. The acceptance of this hypothesis is based on the fact that intercostal neuritis associated with pregnancy disappears within a few hours after delivery.
On the other hand, this could explain why it is more common for pain to arise later in gestation. Similarly, this is a valid argument for why neuropathy affects more the levels closer to the growing abdomen than those nerves in the upper thoracic region.
Radicular compression without herniation
Another reason why thoracic neuralgia is thought to appear in some pregnant women is mechanical nerve entrapment, when the nerve emerges from the spine. This entrapment is the result of the additive action of several factors that are peculiar to pregnancy.
Among them are the following:
- Accentuation of lumbar lordosis to counteract the weight gain in the abdominal region and, thus, to be able to modify the body’s center of gravity.
- Fluid retention as a result of increased blood volume, which predisposes the soft tissues surrounding the spine to swell slightly.
The result is that the stretching caused by hyperlordosis and the increase in size of the paravertebral structures leave less space for the nerves to have a free path. However, the fact that intercostal neuritis does not affect the majority of pregnant women raises the suspicion of other factors.
Ligament laxity due to relaxin action
Finally, increased relaxin, a molecule associated with increased flexibility of the hip joints and ligaments to promote labor, may be involved in the origin of pain. For some authors, relaxin also has an effect on the intervertebral discs, making them more vulnerable to stress.
However, this hypothesis is controversial.
What symptoms does intercostal neuritis cause in pregnant women?
Neuralgia gravidarum produces moderate to severe pain on one side of the chest. It usually follows the path of one or two intercostal nerves and there may be a sensation of numbness in the area.
It’s most often noticeable in the lower levels of the thoracic region. That is, those closest to the abdomen.
A distinctive feature of intercostal neuritis in pregnancy is that palpation of the back muscles increases the painful sensation. Similarly, changes in position may worsen the symptom. The pain may even make it difficult for a woman to move.
Generally speaking, intercostal neuritis most often affects the right side of the chest. In addition, some women report that the pain radiates to the abdomen.
It’s important to note that the symptoms subside after delivery. However, it’s common for this condition to recur in future pregnancies.
Diagnosis of intercostal neuritis in pregnancy
Symptomatology is sufficient to establish the diagnosis.
It’s possible that the physician may consider electromyography to be necessary. Not in order to confirm any finding, but to rule out a more complex cause.
Differential diagnoses to take into account
It’s important to rule out conditions in which there is an underlying nerve lesion. Recall that in intercostal neuritis of pregnancy there does not appear to be nerve damage, but rather the condition is secondary to a mechanical effect.
However, assuming this condition at the outset, without resorting to a proper review, could mask other disorders of greater severity:
- Disc herniation
- Herpes zoster infection
- Diabetic polyradiculopathy
Options to reduce thoracic neuralgia gravidarum
In general, the best treatment for neuromuscular pain due to pregnancy is its prevention, through physical conditioning prior to becoming pregnant. However, this recommendation is not very useful for a patient who already has the condition and for those prone to develop it.
In the literature, treatment is reduced to the indication of acetaminophen and the topical use of lidocaine patches on the affected area, as a last resort to reduce the symptomatology. However, this analgesic management must have strict medical surveillance, due to the possible risks.
The use of amitriptyline is also good for those cases in which pain is intense. But it’s necessary to individually treat each case. Doctors must weigh the risk/benefit ratio against drugs such as this one, which may be harmful during pregnancy.
All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.
- Edmundson, C., Guidon, A. (2017). Neuromuscular Disorders in Pregnancy. Seminars in Neurology, 37(6), 643 – 652.
- Guidon, A. C., Massey, E. W. (2012). Neuromuscular Disorders in Pregnancy. Neurologic Clinics. 30(Issue 3), 889–911.
- Massey, E. W., Guidon, A. C. (2014). Peripheral Neuropathies in Pregnancy. Neurology of Pregnancy, 20(1), 100–114.
- Rezania, K. (2011). Neuromuscular Diseases in Pregnancy. Neurological Disorders and Pregnancy, 159–184.
- Rosier, C., Camdessanché, J. P. (2021). Neuropathy and Pregnancy. Revue Neurologique, 177 (Issue 3), 220–224.
- Skeen, M. B., Egglestone, M. (1999). Thoraconeuralgia Gravidarum, Muscle and Nerve, 22(Issue 6), 779–780.
- Triana, J. D., & Salgado, S. A. (2015). Neuropatías en el embarazo. Revista Repertorio De Medicina Y Cirugía, 24(3), 168–174.
- Weimer, L. (2020). Neuromuscular Disorders in Pregnancy. Handbook of Clinical Neurology, 172(Chapter 12), 201–218.