Acute Calcific Tendonitis of the Longus Colli: An Uncommon Cause of Neck Pain in the Emergency Department

The longus colli muscle has three major parts that originate and insert in the upper cervical and thoracic spine. It is a weak flexor of the neck, and when contracted also serves to rotate the neck to the ipsilateral side. It is innervated by the anterior rami of the C2-C6 spinal nerves and receives its blood supply from the anterior cervical and inferior thyroid arteries. In a post motor vehicle collision (MVC) patients presenting weeks later, the physician has to ensure there is no subacute fracture. Clinically, these patients present with severe anterior neck pain that will often be described as a deep pain. A 43-year-old female with a past medical history of diabetes and prior surgical history of a tonsillectomy and uvulectomy presented with sudden onset of sore throat that woke her up from sleep at 3:00 am. Associated with the sore throat, she had hoarseness of her voice, difficulty breathing and felt that her throat was closing. She forced herself to vomit and then felt better. She denied any fevers or chills. Later, the patient mentioned that she had chronic neck pain from a prior accident and had been told that she has C5-C6 stenosis. About a week prior, she had been involved in another MVC and had some neck pain after that. Significantly, she was also on lisinopril for her hypertension (HTN). She was tolerating secretions, protecting her airway and no gross inflammation was noted on physical exam. On labs, there was no leukocytosis noted. Soft tissue neck X-ray showed reversal of the cervical lordosis, degenerative and erosive changes at C4-C5 and C5-C6, and thickening of the prevertebral soft tissues. She obtained a CT of the neck and cervical spine that showed osteophyte complexes at C4-C5 and C5-C6, as well as calcific tendonitis of the longus colli with a moderate amount of prevertebral free fluid. Neurosurgery was consulted from the ED who recommended getting an MRI of the neck, and consulting ENT as well. ENT happened to be in the ED and performed a bedside laryngoscopy that showed edema of the left arytenoid with full functionality of the vocal cords, and no signs of airway compromise. The patient was started on steroids, antibiotics, H2 blockers, and the ACE-inhibitor was discontinued due to suspected angioedema per ENT. She was also admitted to the ICU for airway monitoring. The MRI of the neck again showed calcific tendonitis of the longus colli with moderate prevertebral fluid. Meanwhile, the patient had complete resolution of her symptoms in 24 hours and she was cleared from both neurosurgery and ENT to be discharged. Acute calcific tendonitis is due to the deposition of calcium hydroxyapatite, which can cause significant pain and edema. In terms of calcific tendonitis of the longus colli muscle, this condition is frequently misdiagnosed and continues to be a challenge, especially in the emergency department. The differential diagnosis is diverse in etiology and severity, ranging from meningitis and retropharyngeal abscess to vertebral fracture and muscle strain.