🩺 Thyroid Examination

The thyroid examination is a multi-step clinical assessment used to evaluate the structure and function of the thyroid gland. It involves a systematic search for local signs (goitre, nodules, bruits) and systemic manifestations of thyroid hormone imbalance. The examination is unique because it requires palpation from behind the patient and observation during functional manoeuvres like swallowing. It is a key clinical skill for diagnosing common endocrine disorders and screening for thyroid malignancy, providing essential context to thyroid function tests.

Thyroid examination is indicated for any patient presenting with symptoms of hyperthyroidism (weight loss, palpitations, heat intolerance, anxiety) or hypothyroidism (weight gain, lethargy, cold intolerance, constipation). It is essential in the workup of a 'neck lump' or an incidentally discovered goitre. Surveillance of known thyroid nodules, autoimmune thyroid disease (Graves' or Hashimoto's), and monitoring of patients on thyroid-altering medications (e.g., Amiodarone or Lithium) also require regular clinical examination. It is a standard part of any 'unexplained tachycardia' or 'weight change' investigation.

There are no absolute contraindications to a thyroid examination. However, deep palpation should be avoided in patients with known acute thyroiditis or very tender nodules to prevent pain. In patients with suspected severe thyrotoxicosis (thyroid storm), the examination should be focused and non-distressing. In cases of a suspected malignant mass that is fixed and hard, palpation should be performed gently to avoid unnecessary patient discomfort. Caution should be exercised with Pemberton's sign (raising arms) in patients with severe cardiac disease or known carotid stenosis, as it can occasionally cause syncope or transient ischaemic attack.

The basic equipment required is a glass of water for the patient to swallow, allowing the clinician to observe the movement of the thyroid and associated structures. A clinician's chair should be used to sit at the same level as the patient during initial inspection, but the clinician must stand behind the patient for palpation. A stethoscope is needed to auscultate the lobes of the thyroid for bruits. Occasionally, a reflex hammer is used to check for the 'hung-up' reflexes associated with hypothyroidism, although this is more relevant to the peripheral neurological element of the thyroid status.

Begin with inspection of the hands (tremor, clubbing, palmar erythema) and pulse. Moving to the face, check for lid lag, lid retraction, and exophthalmos. Inspect the neck from the front at rest, then during swallowing water, and then with tongue protrusion. Transition to palpation from behind the patient; identify the thyroid cartilage and cricoid cartilage to locate the gland. Palpate each lobe while the patient swallows. Feel for the trachea for deviation and palpate the cervical lymph nodes. Percuss the manubrium for retrosternal dullness. Auscultate each lobe for a bruit. Conclude by checking for pre-tibial myxoedema and, if hyperthyroid, proximal myopathy (asking the patient to stand up from a chair without using their arms).

Interpretation involves determining the patient's 'thyroid status' (euthyroid, hypothyroid, or hyperthyroid) and the nature of the gland (diffuse goitre, multinodular, or solitary nodule). A diffuse, smooth goitre with a bruit is highly suggestive of Graves’ disease. A hard, fixed, solitary nodule increases the suspicion of malignancy. Exophthalmos and lid lag are specific signs of Graves' ophthalmopathy. Systemic signs like tachycardia, warm moist skin, and hyperreflexia point towards thyrotoxicosis; whereas bradycardia, dry skin, and delayed reflex relaxation (hung-up reflexes) suggest hypothyroidism. Any palpable nodule in a male or a young person necessitates urgent specialist referral.

One of the most frequent errors is failing to ask the patient to take a sip of water, which is essential to differentiate a thyroid mass (which moves with swallowing) from other neck lumps. Students often forget to auscultate the gland for a bruit, a key sign of Graves' disease. Another common mistake is neglecting to check for 'thyroid acropachy' (clubbing) or pre-tibial myxoedema, focusing only on the neck. Many fail to properly assess for 'obstruction' using Pemberton’s sign in the case of a large goitre. Finally, failing to check for a tremor or eye signs (lid lag and retraction) results in an incomplete assessment of thyroid status.

Always start with a general inspection from the door; the patient's agitation or lethargy can be an immediate clue. Ensure you ask the patient if they have any pain in their neck before you start palpating. When standing behind the patient, use the pads of your fingers and palpate both lobes and the isthmus systematically. Don't forget to check the cervical lymph nodes, as thyroid malignancy often spreads to the local chains. If you find a goitre, remember to check for retrosternal extension by percussing the manubrium (dullness) and performing Pemberton’s sign.

Relevant to 'Endocrinology and Metabolic Medicine' and 'Surgery' modules. Students must differentiate between the thyroid gland (moves with swallowing) and a thyroglossal cyst (moves with swallowing and tongue protrusion). Knowledge of the 'Red Flags' for thyroid cancer (rapid growth, hoarseness, dysphagia, cervical lymphadenopathy) is a frequent exam focus. Understanding the role of TSH and Free T4 in correlating clinical findings with biochemical data is essential. Candidates should be familiar with the Two-Week-Wait (2WW) referral criteria for thyroid nodules.