Calcific tendinitis of the longus colli muscle

Calcific tendinitis of the longus colli muscles is is an inflammatory/granulomatous response to the deposition of calcium hydroxyapatite crystals in the tendons of the longus colli muscle. It is sometimes more generically known as calcific prevertebral tendinitis or, less accurately, as retropharyngeal calcific tendinitis.

Epidemiology

Like other forms of calcific tendinitis, this condition typically occurs in adults in middle age (20-50 years of ageold) with a slight preference for females ³. There is no consistent gender predilection across case series ⁴.

In a retrospective review of adult neck and cervical spine CTs in one American health system, the frequency of acute longus colli tendinitis was 1 in 1000 examinations ⁴.

Clinical presentation

Patients can present with debilitating symptoms that are unrelated to the degree of calcification seen on CT. Symptoms develop acutely and include neck pain, fever, dysphagia, odynophagia, and reduced neck range of movement. White blood cell count and erythrocyte sedimentation rate may be elevated.

Radiographic features

Plain radiograph and CT

Calcifications may be seen on radiographs, but the preferred imaging modality is contrast-enhanced CT. On CT, amorphous calcifications are typically seen in the superior fibres of the longus colli muscle tendons (at the C1-C2 level) ^1-3. Occasionally the inferior fibres may be affected, as low down as T3. The longus colli muscles may also appear hypo-attenuating due to oedema.

Small retropharyngeal effusions and oedema of the adjacent prevertebral soft tissues are also usually seen.

Importantly, enhancement around the effusion is usually minimal and if present, should shift the diagnosis towards a retropharyngeal abscess ³. Adenopathy and bone destruction, likewise, should suggest alternative diagnosis ^1-3. 

MRI

MRI will easily demonstrate oedema; however, a high level of suspicion is needed as the calcifications are much harder to visualise.

As is the case with CT, the presence of peripheral enhancement and/or suppurative lymphadenopathy should suggest infection as the underlying cause ^2,3.

At least one case of localised marrow signal inflammatory has been reported ^1,2. 

Treatment and prognosis

Conservative management with NSAIDs is generally all that is required. Symptoms tend to resolve within a few weeks. 

Differential diagnosis

• retropharyngeal abscess
  • prominent surrounding enhancement
  • diffusion restricting fluid within the collection
  • cervical lymphadenopathy
• trauma
  • prevertebral bone fragments from acute fractures may be mistaken for calcification in the longus colli tendons
• tumour
  • soft tissue mass
  • contrast enhancement
  • cervical lymphadenopathy