Ludwig's angina

Ludwig's angina is an acute cellulitis in the region of the submandibular gland. It is most commonly due to sepsis in the throat or mouth which migrates to the submandibular space. Occasionally, it may be the result of suppuration in the submandibular gland itself.

• it is necessary to consider the anatomy of the submandibular space in order to understand the pathophysiology of Ludwig's angina
  • the submandibular space has a superior border formed the floor of mouth mucosa and an inferior border formed by the superficial layer of the deep cervical fascia as it extends from the hyoid bone to the mandible
    • this space is sub-divided by the mylohyoid muscle into two spaces:
      • the submaxillary space below the mylohyoid
      • the sublingual space above the mylohyoid
      • the submaxillary and subligual spaces are effectively in continuity with one another as infection can spread around the free posterior edge of the mylohyoid
      • also extension of infection posteriorly along the intrinsic tongue musculature can lead to involvement of the parapharyngeal space and retropharyngeal space. If there is posterior extension of infection then there is potential for descent of the infection into the superior mediastinum
• aetiology is odontogenic or periodontal disease in 75% to 90% of cases - infections of the second or third molar affect the beginning of the submaxillary space (1)
  • the roots of the second and third molars teeth extend inferiorly below the mylohyoid line of the mandible and hence provide a route of extension to the submaxillary space
    • spread of infection is extension is limited inferiorly by the superficial layer of the deep cervical fascia
    • infection typically spreads superiorly from the submaxillary space to the sublingual space - this results in induration of the floor of mouth, elevation and posterior displacement of the tongue, and insidious airway compromise
• peak incidence of Ludwig's angina is between 20 and 40 years and there is a male preponderance (2). This condition is also more common in diabetic patients than non-diabetics (2)

Clinically, the patient is ill and toxic with a non- fluctuant swelling below the angle of the jaw. There is oedema of the floor of mouth and around the larynx with elevation and posterior displacement of the tongue. There may be signs of airway obstruction.

Treatment consists of:

• hospital admission is always indicated (2)
• management prorities are airway safety, antibiotic treatment, and surgical drainage. Note that metabolic control and fluid replacement are important adjuncts

Notes:

• infection in Ludwig's angina spreads by continuity along fascial planes, rather than by lymphatics and rarely involves the glandular structures and hence there is generally not an associated cervical lymphadenopathy

Reference:

1. Shockley WW. Ludwig angina: a review of current airway management. Arch Otolaryngology Head Neck Surg May 1999;125 (5): 600–604.
2. Scott A, Stiernberg N, Driscoll. Deep Neck Space Infections; Bailey Head & Neck Surgery–Otolaryngology. 1998, Lippincot-Raven Cap. 58: 819-35.