Otalgia (Ear Pain)

Anatomy: Why Referred Pain Occurs

Primary (Otogenic) Otalgia

Referred (Secondary) Otalgia

1. Via CN V (Trigeminal) - Dental and TMJ

• Dental caries, abscesses, periodontal disease
• Erupting/impacted third molars (wisdom teeth)
• Post-extraction pain
• Temporomandibular joint (TMJ) dysfunction / CSDD (craniomandibular-cervical disorders):
  • Bruxism, clenching, TMJ osteoarthritis, musculoskeletal pain of the muscles of mastication
  • TMJ imaging may be abnormal in ~20% of asymptomatic individuals, so results must be interpreted alongside clinical findings
  • First-line treatment: conservative - analgesia and physiotherapy

2. Via CN IX / CN X - Pharyngeal, Laryngeal, and Oesophageal

• Tonsillitis / peritonsillar abscess - classic, easily recognized
• Head and neck malignancy - a critical not-to-miss diagnosis:
  • Oropharyngeal carcinoma (tonsil, tongue base) - referred via CN IX; may be the sole presenting symptom
  • Isolated unilateral otalgia without otoscopic findings is a red flag for occult aerodigestive tract malignancy
  • Hypopharyngeal and supraglottic carcinoma - otalgia and odynophagia are common presenting features via CN X (Arnold's nerve)
  • Nasopharyngeal carcinoma - otalgia reported in up to 14% of cases
  • Infratemporal fossa tumours (adenoid cystic carcinoma, SCC, osteogenic sarcoma) - referred via CN V, Arnold's or Jacobson's nerve
• Laryngopharyngeal reflux (LPR) - implicated in both children and adults; upper airway mucosa is more sensitive to acid damage than oesophageal epithelium, so otalgia can occur without typical reflux symptoms

3. Via CN X - Vagus (cardiac)

• Cardiac pain can present as otalgia - an important consideration in older patients

4. Via C2-C3 - Cervical

• Cervical spondylosis / musculoskeletal neck disorders
• Cervical lymphadenopathy, thyroid disease, neck masses

5. Neuralgias (diagnoses of exclusion)

• Glossopharyngeal neuralgia: Severe, transient, stabbing pain in the ear, base of tongue, tonsillar fossa, or beneath the angle of the jaw. Incidence: 0.2-0.7/100,000/year. Triggered by swallowing, coughing, yawning, or talking. Two types: tympanic (mainly ear pain) and oropharyngeal (mainly throat pain). Paroxysmal, lasting seconds to minutes, with remission periods. Often misdiagnosed due to rarity.
• Herpes zoster oticus (Ramsay Hunt syndrome): Severe acute otalgia from geniculate ganglion involvement, preceding vesicle eruption; can persist as post-herpetic neuralgia
• Trigeminal neuralgia: Otalgia is an infrequent but possible feature
• Great auricular neuralgia, carotidynia

Clinical Assessment

• Pain characteristics: acute vs. chronic, nociceptive vs. neuropathic
• Associated otological symptoms: hearing loss, otorrhoea, tinnitus, fullness
• Systemic red flags: dysphagia, voice change, weight loss, odynophagia, oral lesions, neck mass
• Social history: tobacco and alcohol use (aerodigestive malignancy risk)
• Dental/jaw symptoms: pain on chewing, jaw clicking, bruxism
• Prior treatments and opioid use (for chronic pain)

1. Full otoscopy (EAC, TM, middle ear)
2. Pinna and periauricular inspection
3. Cranial nerve examination
4. Oral cavity, oropharynx
5. Flexible nasendoscopy (pharynx, larynx, nasopharynx) - essential in unexplained otalgia
6. Neck examination (lymph nodes, salivary glands, thyroid)
7. TMJ and dental examination
8. Cervical spine assessment

• Otalgia with normal otoscopy, no discharge, and no hearing loss = presumed referred until proven otherwise
• Expert dental/TMJ examination should be part of the workup
• Full upper aerodigestive tract evaluation is mandatory in unexplained otalgia
• Isolated unilateral otalgia = red flag for occult aerodigestive malignancy

Investigation

• Cummings Otolaryngology Head and Neck Surgery, p. 2635
• Scott-Brown's Otorhinolaryngology Head & Neck Surgery, Vol. 2, p. 1187-1189

Summary: Differential at a Glance

OTALGIA
│
├── Otoscopy ABNORMAL → Primary otalgia
│     ├── Otitis externa / furuncle / bullous myringitis
│     ├── Otitis media (AOM / chronic / with complications)
│     ├── Cholesteatoma / mastoiditis
│     ├── Herpes zoster oticus (Ramsay Hunt)
│     └── Ear canal / middle ear malignancy
│
└── Otoscopy NORMAL → Referred otalgia (work up systematically)
      ├── Dental / TMJ (most common in adults)
      ├── Oropharyngeal / tonsillar (tonsillitis, peritonsillar abscess)
      ├── Head and neck malignancy ⚠ (red flag)
      ├── Laryngeal / hypopharyngeal pathology
      ├── Laryngopharyngeal reflux (LPR)
      ├── Cervical spine disease
      ├── Cardiac pain ⚠
      └── Neuralgias (glossopharyngeal, post-herpetic, geniculate)
            → Diagnoses of exclusion; MRI cranial nerve required

• Scott-Brown's Otorhinolaryngology Head & Neck Surgery, Vol. 2, Chapter 92 (Otalgia), pp. 1185-1189
• Cummings Otolaryngology Head and Neck Surgery, Chapter 137, pp. 2634-2635
• Tintinalli's Emergency Medicine: A Comprehensive Study, Chapter 242, p. 966

Otalgia - Bailey & Love's Short Practice of Surgery (28th Edition)

Sensory Nerve Supply of the Ear and Basis for Referred Otalgia

"This complicated and rich sensory innervation means that referred otalgia is common and may originate from the normal area of distribution of any of the above nerves. A classic example is the referred otalgia caused by cancer of the larynx or hypopharynx."

• The skin on the outer surface of the eardrum migrates outwards so the ear canal is "self-cleaning"
• Infection of the middle ear and mastoid can easily spread to the cranial cavity
• The facial nerve pursues a tortuous course through the middle ear
• The ear has a rich sensory innervation so that 'referred otalgia' is common
• Cancer of the larynx or lower pharynx can present with otalgia

History Taking in Otalgia

• Earache, pain and itch
• Hearing loss
• Discharge: type, quantity and smell
• Tinnitus
• Vertigo
• Facial weakness
• Speech and development (in children)
• Past history: head injury, baro- or noise trauma, ototoxics, family history, previous ear surgery

Referred Otalgia - Specific Clinical Contexts in Bailey & Love

1. Acute Tonsillitis

"This common condition is characterised by a sore throat, fever, general malaise, dysphagia, enlarged upper cervical nodes and sometimes referred otalgia."

• ~50% bacterial (Group A Streptococcus), ~50% viral (including EBV/glandular fever)
• Throat swab + blood for EBV testing recommended
• Treatment: Paracetamol, analgesia, saline gargles, phenoxymethylpenicillin (penicillin V); ampicillin avoided (risk of rash in EBV)

2. Post-Tonsillectomy Otalgia

"Patients are allowed home on the same or following day and are warned that they may experience otalgia as a result of referred pain from the glossopharyngeal nerve..."

• Referred pain via CN IX after tonsillectomy is an expected post-operative finding
• Patients are counselled preoperatively about this
• Complications of tonsillectomy also listed as: haemorrhage (immediate or late), infection, pain/otalgia, postoperative airway obstruction, velopharyngeal insufficiency

3. Hypopharyngeal Carcinoma

"The diagnosis of hypopharyngeal carcinoma should be considered in all patients presenting with dysphagia, hoarseness or referred otalgia, particularly if they have a history of smoking or significant alcohol consumption."

• Fibreoptic endoscopy in clinic may show only subtle signs (oedema, unilateral pooling of saliva in piriform fossa)
• Not well visualised on flexible gastroscopy
• Preferred investigation: direct rigid pharyngoscopy + oesophagoscopy with biopsy under GA
• MRI or CT of neck + CT thorax/upper abdomen for staging
• Alcohol and tobacco are the two principal carcinogens (for non-HPV tumours)

4. Nasopharyngeal Carcinoma (NPC)

• Hearing loss (unilateral serous otitis media)
• Otalgia
• Nasal obstruction, bloody discharge, epistaxis
• Cranial nerve palsies (especially CN III-VI then IX-XII)
• Trismus

5. Oral Cavity Neoplasm (Late-Stage)

"Reduced tongue movement, sensory nerve deficit, trismus, otalgia and dysphagia are all in keeping with late-stage disease."

Key Teaching Points from Bailey & Love on Otalgia

1. Referred otalgia is common due to the ear's complex multi-nerve sensory supply (CN V, VII, IX, X + cervical nerves C2/3)
2. Any pathology within the distribution of these nerves can cause ear pain - this is the fundamental mechanism
3. Cancer of the larynx or hypopharynx is the classic red-flag cause of referred otalgia - always consider in smokers/alcohol users presenting with ear pain + dysphagia/hoarseness
4. Post-tonsillectomy otalgia via the glossopharyngeal nerve is a normal expected finding - patients must be warned
5. Acute tonsillitis commonly produces referred otalgia via CN IX
6. Chronic otalgia is a symptom of late-stage oral cavity malignancy
7. Nasopharyngeal carcinoma can present with otalgia as part of its local symptom complex