What Might Cause Numbness in the Left Pectoral Muscle?

One common cause is pectoralis minor syndrome. This happens when the pectoralis minor muscle, located beneath the pectoral muscles, becomes tight or overworked. It can press on nerves that come from the brachial plexus under the collarbone. When these nerves are squeezed, you might feel numbness in the pectoral area. Another possibility is intercostal neuralgia. The intercostal nerves run between the ribs and help make the chest and pectoral muscles feel normal. If one of these nerves is irritated by injury, strain, or even inflammation, numbness (and sometimes pain) might appear. It’s also important to remember that sometimes other nearby conditions, like issues with the chest wall, can cause similar feelings. If someone experiences these symptoms, it is a good idea to visit a doctor to look into the problem and figure out the most helpful way to feel better.