A cricopharyngeal spasm (CPS) is an involuntary tightening of the cricopharyngeus muscle, a ring of muscle at the top of the esophagus (the upper esophageal sphincter or UES). This muscle is typically contracted to prevent air from entering the esophagus and to stop stomach contents from flowing back up. During a spasm, the muscle contracts too much, leading to the uncomfortable sensation of a lump, or “golf ball,” stuck in the throat, medically termed globus pharyngeus. The causes of this hypercontraction are complex, often involving chemical irritation, nerve and muscle coordination issues, and psychological factors.
Reflux and Chemical Irritation
One frequent cause of cricopharyngeal spasm is the backflow of stomach contents into the throat and voice box area. This condition is known as laryngopharyngeal reflux (LPR), or silent reflux. LPR involves gastric contents bypassing both the lower and upper esophageal sphincters to reach the delicate tissues of the laryngopharynx. Unlike gastroesophageal reflux disease (GERD), LPR often occurs without the classic symptom of heartburn.
The irritation is caused by chemical components of the refluxate, including stomach acid, pepsin, bile, and trypsin. These substances damage the specialized lining of the throat and larynx, which lacks the protective layer found in the lower esophagus. The resulting inflammation is thought to cause the cricopharyngeus muscle to involuntarily tighten as a protective reflex. This chemical irritation creates a hyper-reactive state in the muscle, leading to the persistent sensation of constriction.
Neurological and Muscular Coordination Issues
Cricopharyngeal spasm can also result from problems with the nervous system’s control over the swallowing process. The cricopharyngeus muscle must relax precisely when a person swallows to allow food to pass into the esophagus. If the coordination between the brain and the muscle is disrupted, this relaxation may be impaired or delayed, causing a spasm or a sensation of obstruction.
Conditions affecting the nervous system, such as stroke, multiple sclerosis (MS), or Parkinson’s disease, can interfere with the signals regulating this muscular function. Neurological damage can disrupt the precise timing required for the muscle to open. Neurodegenerative disorders like Parkinson’s disease can also lead to abnormal muscle movements or hypertonicity in the throat muscles. In these cases, the spasm is a manifestation of oropharyngeal dysphagia, a broader swallowing dysfunction.
Psychological Stress and Somatic Manifestation
Stress is a significant factor in causing cricopharyngeal spasms, as the muscle is sensitive to emotional and psychological states. Chronic anxiety and emotional distress can lead to the involuntary tensing of neck and throat muscles, known as somatic manifestation. This tension manifests as a feeling of constriction, similar to how stress causes tightness in the shoulders.
The term globus pharyngeus is often used when the lump sensation is primarily linked to emotional factors. Individuals experiencing high anxiety may develop visceral hypervigilance, meaning they become acutely aware of normal bodily sensations. This heightened sensitivity amplifies a minor muscle contraction into a troublesome spasm. A key indicator of a psychological link is that the sensation often lessens or disappears while actively eating or drinking.
Determining the Underlying Cause
Determining the precise underlying cause of cricopharyngeal spasm requires a structured diagnostic process, as origins can be chemical, neurological, or psychological. A physician typically begins with a thorough medical history, asking detailed questions about the timing of symptoms, emotional state, and whether the spasm is relieved or worsened by eating.
Diagnostic tools are used to visualize the swallowing mechanism and assess muscle function:
- Video fluoroscopic swallowing study (VFSS), which involves swallowing barium-coated liquid and food, provides a real-time X-ray video of the throat and esophagus. This helps check for structural issues, such as a cricopharyngeal bar, and assesses muscle coordination.
- Esophageal manometry measures the pressure and coordination of muscle contractions in the upper esophageal sphincter.
- An upper endoscopy may be performed to visually inspect the throat and esophagus for signs of irritation or damage from reflux.