Heartburn, often experienced as a burning sensation rising into the chest and throat, is a common digestive complaint that can sometimes manifest in surprising ways. While most people associate acid reflux with chest discomfort, some individuals report pain seemingly unrelated to the stomach or esophagus. This has led many to question whether this digestive issue could be the source of discomfort felt in the upper back. Understanding how the body’s nervous system processes pain signals explains this unusual connection.
Understanding Referred Pain: The Link to the Shoulder Blades
The phenomenon that links stomach acid to upper back discomfort is known as referred pain. This occurs when internal organ pain is perceived by the brain as originating from a distant, superficial area of the body. Nerves supplying internal organs (viscera) share pathways in the spinal cord with nerves supplying the skin and muscles (somatic structures), a process called viscero-somatic convergence.
When acid irritates the esophagus, the visceral sensory nerves send signals to the spinal cord segments, typically in the mid-thoracic region. These same spinal segments also receive signals from the nerves innervating the upper back and the region between the shoulder blades. Since the nervous system has a lower density of sensory fibers for internal organs, the brain misinterprets the intense esophageal signal as coming from the more familiar somatic area. This results in the confusing sensation of pain localized between the shoulder blades, even though the problem lies within the digestive tract. The phrenic nerve, which supplies the diaphragm, also carries sensory information from the upper abdomen and can contribute to pain referred to the shoulder area.
Defining Acid Reflux and Its Typical Symptoms
The digestive issue commonly called heartburn is known as acid reflux, and when chronic, it is classified as Gastroesophageal Reflux Disease (GERD). This condition begins with the lower esophageal sphincter (LES), a ring of muscle located at the junction of the esophagus and the stomach. The LES functions as a one-way valve, relaxing to allow food into the stomach and then quickly closing to prevent stomach contents from backing up.
Acid reflux occurs when this sphincter muscle fails to close completely or relaxes too frequently, allowing stomach acid to flow backward into the esophagus. The lining of the esophagus is not equipped to handle the acidic stomach contents, leading to irritation and inflammation. Symptoms include a burning sensation in the chest rising toward the throat (heartburn), regurgitation of sour or bitter-tasting liquid, difficulty swallowing, or a persistent sore throat.
Beyond Heartburn: Other Causes of Back Pain
While acid reflux can cause pain between the shoulder blades through referred sensation, back pain in this area has many potential causes, some of which are serious. Pain between the shoulder blades should never be automatically attributed to heartburn alone. Musculoskeletal issues are the most frequent source of upper back discomfort, often related to poor posture, prolonged sitting, or muscle strain from repetitive activities.
The pain can also signal problems involving the lungs, such as pleurisy or a pulmonary infection, which can cause sharp pain in the chest that radiates to the back. Most significantly, pain in the upper back or shoulder blades can be an atypical presentation of a heart attack. While the classic symptom is crushing chest pain, many people, particularly women, may experience discomfort that radiates to the back, neck, jaw, or arm.
If back pain is accompanied by signs like shortness of breath, a cold sweat, lightheadedness, or pain that feels like pressure or tightness, immediate medical attention is necessary. These symptoms, along with pain that occurs during exertion, is not relieved by antacids, or is unrelated to meals, serve as red flags that warrant prompt professional evaluation.
Lifestyle Adjustments for Relief
Addressing pain caused by acid reflux begins with specific adjustments to daily habits that reduce the frequency and severity of reflux episodes.
Dietary and Meal Adjustments
One effective strategy involves dietary modifications, starting with identifying and avoiding trigger foods. Common culprits that relax the LES or increase stomach acid production include fatty or fried foods, chocolate, caffeine, alcohol, and acidic items like citrus fruits and tomatoes. Eating smaller, more frequent meals reduces pressure on the lower esophageal sphincter.
Positional Changes
- Remain upright for at least two to three hours after eating and avoid consuming food close to bedtime.
- Elevate the head of the bed by six to nine inches using blocks or a wedge pillow to use gravity to keep stomach acid down.
- Losing excess weight is another intervention, as extra abdominal weight places pressure on the stomach, which can force acid back up into the esophagus.