Harrison’s groove, also sometimes called “Harrison’s sulcus,” is the medical name for a dip or crevice in the chest where the ribcage meets the diaphragm. This sort of dip isn’t normal, but it isn’t always problematic either. It’s usually noticed in infancy or early childhood, and sometimes it will fix itself. The most common causes are a lack of essential minerals or poor muscle tone, both of which can improve over time. In more serious cases, the groove is caused by a chronic respiratory problem like asthma that weakens the bones and muscles over long periods of time spend coughing and wheezing; it can also be caused by rickets, a disease triggered by extreme vitamin deficiencies and absorption problems. Depending on when it’s diagnosed, the groove can’t always be corrected, though medical experts usually have a number of ways to prevent further damage and allow patients to lead full lives.
How It’s Noticed
In the vast majority of cases, the groove becomes obvious during early infancy, and it’s often most noticeable in newborns. Concerned parents often feel the indentation when dressing or bathing their babies, and pediatricians often note it during routine exams. In most of these cases, the indentation is caused by weak bones and muscles. They may have been formed poorly in the womb, or the baby may not be getting enough milk or nutrition in early life to thrive. In most cases, it will usually fill out as the baby grows and gets stronger.
The condition is often a bit more troubling when it’s first noticed in older children or adults. People who once had normal ribcages and torso bone structures who then develop an indentation or dip may be suffering from a more serious medical condition, and usually need to be evaluated by a professional to get to the root cause.
Concerns Related to Respiratory Disease
When Harrison's groove presents later in life, it’s most often related to some sort of chronic respiratory problem. The constant coughing and struggling to breathe that is commonly associated with things like lung disease, asthma, or obstructive respiratory disease can eventually lead to a breakdown and weakening of the chest wall. This, in turn, can cause the muscles supporting the bones to disintegrate and essentially collapse, which can leave a noticeable gap or indentation.
The good news for patients is that most respiratory conditions can be controlled through medication and other therapies. With time and the right treatments, the groove may become less prominent and can sometimes actually heal itself. At other times it may grow worse, though, which is often a sign that more help is required.
Connection to Rickets
The groove can also be a sign of rickets, a rare disorder that primarily affects children. Rickets is a weakening of the bones caused by the body not being able to properly absorb and metabolize vitamin D. This leads to additional deficiencies in calcium and magnesium. It causes the bones to become brittle, and it can eventually lead to deformities in some individuals. The appearance of Harrison's groove is just one potential symptom of this disease, but is often one of the first that’s noticed or discovered.
Rickets is relatively uncommon in most parts of the world thanks to fortified foods and the wide presence of nutritional education, although certain populations may still be at risk. One of the best ways for mothers to lower the risks in their children is to be sure to get enough vitamin D and calcium during pregnancy. Babies and young children also need adequate stores of these minerals during development. In rare cases, rickets can also develop later in life, but when this happens it’s often a sign of something more than just dietary deficiencies — usually a metabolic problem or digestive issue that’s preventing nutrients from being absorbed or used properly.
When to Get Help
It’s usually a good idea for anyone notices this sort of crevice to get a professional opinion. There may not be any cause for alarm, but if there is an underlying condition at the root of the depression, the earlier treatment gets started, the better the outcome is likely to be. Trained professionals may be able to make a diagnosis with just a physical exam, but lab work and blood analysis might be required, too.