The Neck

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Generalities

The neck is an important crossroad of anatomic structures and organ systems, the most important of which is the thyroid (discussed in Chapter 8 ).

• 1.

  What neck features should be identified during inspection?

  The most important is the contour . Abnormalities include:

  • A buffalo hump at the base of the neck.

  • A short neck , which is suggestive of Klippel-Feil syndrome or sleep apnea syndrome.

  • Pterygium colli (from the Greek pterygion , wing). A webbed neck is seen in Turner’s syndrome, Noonan’s syndrome, and Bonnevie-Ullrich syndrome.

• 2.

  What is Turner’s syndrome ?

  A syndrome characterized by ovarian dysgenesis in phenotypic females with X-monosomy, short stature, low-set ears, shield chest, heart defects (especially coarctation), café-au-lait spots, freckles, and a webbed neck. It was first described in 1938 by Henry H. Turner, founder of the Endocrine Society and a University of Oklahoma endocrinologist.

• 3.

  What is Noonan’s syndrome ?

  A syndrome characterized by congenital heart defects (usually pulmonic stenosis) in a setting of pectus carinatum, short stature, mental retardation, hypertelorism, and a webbed neck. Females are fertile, but males tend to be cryptorchic with high gonadotropins. Bleeding and dermatologic abnormalities are common. It was first described in 1963 by US cardiologist Jacqueline Noonan and pediatrician Dorothy Ehmke.

• 4.

  What is Bonnevie-Ullrich syndrome?

  A syndrome characterized by skeletal and soft tissue abnormalities, such as lymphedema of the hands and feet, nail dystrophy, skin laxity, short stature, and, of course, a webbed neck. It was first described by US geneticist Kristine Bonnevie (1872–1950) and German pediatrician Otto Ullrich (1894–1957). When associated with Klippel-Feil syndrome, it goes under the name of Nielsen disease.

• 5.

  What is Klippel-Feil syndrome?

  First described in 1912 by the French neurologists Maurice Klippel and André Feil, this syndrome consists of congenital fusion of two or more cervical vertebrae, producing a low posterior hairline and a short neck that often causes retroflexion of the head (opisthotonos). This may even lead to neurologic compromise, such as platybasia (a developmental anomaly of the skull causing the floor of the posterior cranial fossa to bulge upward into the foramen magnum), cord compression, cervical instability, and motility impairment. There also may be cardiac defects, ocular malformations, and various urogenital anomalies (renal agenesis).

• 6.

  With what syndrome is a buffalo hump at the base of the neck most commonly associated?

  Cushing’s syndrome.

• 7.

  What are the anterior and posterior triangles of the neck?

  They are important regions of the lateral neck, separated from each other by the sternocleidomastoid muscles (SCMs) ( Fig. 7.1 ). These can be easily located through inspection and palpation, especially if tensed against resistance. The remaining borders of the posterior triangle are the anterior margin of the trapezius and the upper margin of the clavicle, whereas the remaining borders of the anterior triangle are the mandible and midline.

  

• 8.

  What are the contents of the cervical triangles?

  • In the anterior triangle , one can often palpate the jugulodigastric node. Other nodes are instead undetectable, unless enlarged by infection, inflammation, or malignancy. The anterior triangles also may harbor important embryologic remnants, such as thyroglossal duct/cysts, branchial cysts, and dermoids.

  • In the posterior triangle , there are many undetectable nodes that can become enlarged after a pharyngitis or a viral upper respiratory illness (URI).

  • The subclavian artery may be felt pulsating at the base of the neck, just above the clavicle.

  • The transverse process of the atlas may be palpated high in the neck, between the mandibular angle and mastoid process. It may be misinterpreted as a cervical mass.

  • The pulsatile common carotid artery (and its prominent bifurcation) is usually felt more laterally, along the SCM.

• 9.

  Which swellings may be encountered during inspection of the neck?

  Many. Classification and origin depend on location (posterior or anterior triangle; and for the latter, midline or lateral aspect) and nature (inflammatory or neoplastic) ( Table 7.1 ).

  Table 7.1

  Neck Masses

  ANTERIOR TRIANGLE
  Midline
  Mostly thyroidal – goiter/nodule(s)
  Thyroglossal (duct) cyst
  Thyroglossal fistula
  Dermoid (cyst)
  Lateral Aspect
  Branchial cleft cyst
  Branchial fistula
  Branchial hygroma
  Cystic hygroma
  Laryngocele
  Masseter muscle hypertrophy

  POSTERIOR TRIANGLE
  Neoplastic
  Lymphomas
  Metastatic
  Neurogenic
  Paragangliomas/glomus tumors
  Miscellaneous (ectopic salivary)
  Inflammatory: Localized
  Tuberculous lymphadenitis (scrofula)
  Bacterial lymphadenitis (abscess)
  Suppurated branchial or thyroglossal cyst
  Inflammatory: Diffuse
  Ludwig’s angina

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Swellings of the Anterior Triangle (Midline)

• 10.

  What is the origin of midline swellings of the anterior cervical triangle?

  They are mostly thyroidal (goiters or nodules). Less commonly, they represent remnants of embryonic structures, such as dermoids or thyroglossal duct cysts ( Fig. 7.2 ). Since only thyroid and laryngeal structures ascend with deglutition, nonthyroidal masses can be easily identified by asking the patient to swallow.

  

• 11.

  What is a thyroglossal (duct) cyst?

  A swelling in the remnant of the thyroglossal duct , which in the embryo connects the thyroid to its point of origin at the base of the tongue. The duct usually disappears in the adult, leaving only a pit at its site of departure (the foramen cecum of the tongue). In some subjects, however, it may persist as an anomalous tract connecting the foramen cecum to the thyroid isthmus. In a few patients, this tract may even harbor a cyst or a fistula.

  Although a thyroglossal cyst can occur anywhere along the path of the duct, most are found near the hyoid bone and thyrohyoid membrane (i.e., under the deep cervical fascia). These usually present as a tense, nontender, mobile, and nonlobulated midline mass, with acute tenderness and fluctuation, suggesting spontaneous hemorrhage or infection. Thyroglossal cysts may at times be just off the midline, pushed laterally by the convexity of the underlying thyroid cartilage and hyoid bone.

  Still, since they are thyroidal in origin, they typically ascend with swallowing. Hence, they can be differentiated from the thyroid by their unique ability to rise with protrusion of the tongue (because of their firm attachment to the tongue’s base). A lingual protrusion can be carried out by holding the suspected cyst between the thumb and index finger and then asking the patient to stick out the tongue as forcefully as possible. Alternatively, one can ask the patient to try to touch the chin with the tongue.

• 12.

  Do thyroglossal cysts transilluminate?

  No – which is counterintuitive, considering their cystic nature.

• 13.

  How common is a thyroglossal cyst?

  Quite common. In fact, of all congenital neck masses, 75% are thyroglossal duct cysts.

• 14.

  What accounts for the other 25% of congenital neck masses?

  Branchial cleft cysts , typically located more laterally, just between the SCM and hyoid.

• 15.

  What is a thyroglossal fistula ?

  A fistulous opening of the thyroglossal duct – a less common entity than a thyroglossal cyst . It presents as a midline pit over the cricoid, intermittently draining and recurrently infected.

• 16.

  What is a dermoid (cyst)?

  A bizarre and usually benign tumor that may occur in any line of embryologic fusion. In the neck, it presents as a midline swelling of the anterior triangle, typically in the submandibular region (just above the hyoid) but occasionally in the lower and suprasternal region. It also may cause swelling in the mouth floor, typically pushing the tongue upward. Dermoids are remnants of embryonic skin and thus may contain hair and cheesy epithelial debris, especially when located in the gonads. They are usually small (<2 cm), soft, and occasionally fluctuant. They are not attached to the skin and do not move with swallowing, but they do transilluminate. They present in young adults or children as asymptomatic and slow-growing masses.

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