Acute longus colli tendinitis (LCT), is often not suspected in patients with severe neck pain. It is an uncommon form of hydroxyapatite deposition disease with distinctive, characteristic imaging findings. Because the features of LCT are visible on CT imaging of the neck, being prepared to correctly identify them is important.
Although the condition is benign and self-limiting, LCT symptoms can mimic severe and sometimes life-threatening conditions such as retropharyngeal abscess, meningitis, or infectious spondylodiscitis. Indeed, LCT’s most common symptoms are severe neck pain, painful restriction of neck movement, dysphagia, and odynophagia. Many patients have fever and/or elevated white blood count. Prompt diagnosis can avoid unnecessary and invasive procedures.
Radiologists at the University of Pittsburgh Medical Center (UPMC) noticed a significant number of cases of LCT during their clinical duties. They decided to retrospectively review all CT examinations of the neck and cervical spine performed in a prospectively chosen 90-day period to determine the frequency of the condition. Two staff radiologists and four diagnostic radiology residents analyzed 8,101 examinations performed on adult patients to determine frequency based on age, sex and clinical history. Their findings have been published in an article in Emergency Radiology.
The longus colli muscle lies on the anterior surface of the vertebral column, extending from T3 through the C1 levels. It consists of vertical, inferior oblique, and superior oblique portions. The superior oblique portion attaches inferiority on the transverse processes of C3 through C5, and superiorly to the anterior tubercle of C1. In ACT, calcification is seen at the
upper myotenious junction of the superior oblique portion. On CT examination, the calcification has an “amorphous” appearance without cortication or internal trabeculae. (Figure 1) Bilaterally symmetric edema outlines the anterior border of the longus colli muscles.
Figure 1. A 49-year-old-male presented with several day history of worsening neck pain (A). Note amorphous calcification anterior to cervical spine at C1-2 level (star). Also thickening of prevertebral tissues in upper and mid neck (arrows). On axial images (B) the calcification (arrow) is seen to lie at the upper myotendinous junction of the superior oblique portion of the bilateral longus colli muscles, in this patient preferentially on the right. Bilaterally symmetric edema (C, arrows) most prominent at C3 level outlines the anterior margin of the longus colli muscles.
The researchers identified 9 positive cases (7 men and 2 women). All positive patients had experienced neck pain, dysphagia, or odynophagia for 2-14 days. All cases displayed the characteristic amorphous calcification as well as edema (measuring between 3-8 mm in greatest anteroposterior dimension and 18-55 mm in craniocaudal extent).
Although the frequency of acute LCT was only 1.1 case per 1000 examinations, this rate increased to 11.4 per 1000 when patients when calculated for those patients who had not had experienced recent trauma, and in whom there was no concern for tumor, postoperative complications, or signs of infection localized to the neck. Variation with age and sex was not significant.
The authors conclude that acute longus colli tendinitis is seldom suspected by ordering physicians, and that radiologists should have increased suspicion for this condition where a patient presents with severe acute onset neck pain in the absence of clear etiology. Their findings also confirm previous reports that the edema lacks an enhancing rim. The authors also advise that intravenous contrast is not necessary to make the diagnosis.
Identifying acute longus colli tendinitis on CT. Appl Radiol.