Endocrinology Objectives (Thyroid Exam) 

Introduction:
The thyroid exam is part of the routine physical exam and should be included when seeing a new patient for the first time.

The thyroid gland may examined anteriorly or posteriorly. The correct way is the way you feel the most confident in performing.

When examining the thyroid gland, remember the following steps:

• Inspection
• Palpation
• Percussion
• Auscultation

Inspection:
Always offer the patient a glass of water. It is very hard to swallow when your mouth and throat are dry.

You should inspect while the patient is at rest as well as when they take a drink of water. The thyroid gland should move with swallowing.

You should first make out the classic landmarks: thyroid cartilage, cricoid ring and the two heads of the sternocleidomastoid. The thyroid isthmus should lie right on top of the cricoid ring or just beneath it. Next imagine that the thyroid gland resembles the letter H where each vertical line represents a lobe and the horizontal crossbar is the isthmus. Most people will have very little palpable thyroid tissue present and part of the lobes may be tucked under the muscle bellies of sternocleidomastoid muscle. When the thyroid is enlarged it becomes more like a butterfly where each wing represents a lobe. A general rule is that each lobe should be no bigger than the patient's thumb or it would be considered enlarged. Most thyroid glands would be 15 to 20g.

When you inspect, you are observing the overall size of the thyroid and whether there is any asymmetry or masses.

You may also look to see if there is any increase in the A-P diameter of > 2mm which would be consistent with thyroid enlargement. You can look for blunting of the base of the sternocleidomastoid muscle which would also suggest thyroid enlargement.

Palpation:
You should palpate each lobe at rest as well as when the patient swallows. You are palpating for the overall size of the thyroid, the texture, for nodularity and tenderness.

It is important to comment on: whether or not the thyroid is enlarged, is there any asymmetry, what is the texture, is there any nodules and is there any tenderness. You may ask the patient to relax their head over towards their shoulder. This allows access to the thyroid lobe under the sternocleidomastoid muscle for that same side.

The texture of the thyroid in Graves' disease has been described as being fleshy like a peach. The texture in Hashimoto's thyroiditis is firm and rubbery.

If you palpate a nodule you should comment on the size, whether it moves with swallowing or whether it is firm or fixed. I would then check for cervical lymph nodes as well.

Percussion:
This step is done if you are suspecting a retrosternal thyroid gland. Please note that percussion is done anteriorly between the ribs around the sternum and not the neck! If there is dullness to percussion retrosternally than this suggests a retrosternal goitre. You can follow this up further by checking for Pemberton's sign. Have the patients raise their arms above their head. If their face turns blue, this suggests a massive goitre with tracheal compression and venous engorgement. Don't try this again.

Auscultation:
Using the bell of your stethoscope and not the diaphragm, carefully auscultate over each lobe as well as the isthmus. Usually you hear nothing. In Graves' hyperthyroidism, however, you may hear a thyroid bruit as the gland is so vascular.

Peripheral Manifestations of Thyroid Disease

Eyes:
Check for lid lag and stare. If you can see the white sclera above the iris when you look at a patient, then this is called stare. There is increased stimulation of the sympathetic nerves to the lids which keeps the eyes more open. Just think about the time you came out of a scary movie! Part two of this is to check for lid lag. You should get the patient to focus on your pen and hold it up high. As you bring the pen down, the eyes will follow the pen and normally the lids would too but if they lag behind this is called lid lag. Lid lag and stare may be seen with any type of thyrotoxicosis.

Graves' eye disease only occurs in Graves' hyperthyroidism. Here the eyes become a little "bulgy". There are many terms for this: Graves' ophthalmopathy, proptosis, Graves' orbitopathy, exophthalmos etc. The eyes start to protrude and stick out. As the extra ocular muscles become swollen, they push the eyes forward. The patient may complain of a gritty sensation in their eyes and this is a sign that the eyes are drying up as they are exposed more to the air. They may also notice diplopia or double vision. This is due to entrapment of the muscles. The eyes may become irritated and red: conjunctivitis. There may be periorbital edema, upper lid retraction, or lower lid retraction. If the conjunctivitis is severe, this is called chemosis. If the eye is severely exposed, corneal ulceration may result. If there is extreme swelling of the eye muscles, compression of the optic nerve may result in loss of central vision. The patient may also complain of a pressure behind the eye.

Along with inspection of the eyes, you should also check for the extraocular movements and whether or not they are experiencing double vision in any of the directions. You should look at the fundi. You should also estimate the degree of proptosis by measuring how far the eyes protrude anteriorly. Normal is less than 18 mm. Endocrinologists will use their exophthalmometer!

Hands:
There are so many findings here. Wow! First have the patient hold their hands out straight and look for tremor. By placing a piece of paper on top of the hands will bring out the tremor. Next feel their hands. They probably feel hot! Compare this to hypothyroidism where the fingers can become icy cold. In hyperthyroidism, the skin typically becomes silky smooth. There may be palmar erythema, and increased sweating of the palms. Check their pulse: there may be tachycardia. Whereas in hypothyroidism, you would expect bradycardia. You should look for onycholysis which is separation of the nail from its bed. You should also check the reflexes which are quite brisk in hyperthyroidism. Clubbing of the nails may be seen in Graves' disease.

Pretibial Myxedema:
While this may be seen in severe hypothyroidism and is described as non pitting edema of the lower shins, it may also be present in patients with Graves' disease. Please note that while about 40 % of patients with Graves' disease will have Graves' eye disease, only 1 % will have pretibial myxedema. If a patient has pretibial myxedema, then there is a good chance they will also have Graves' eye disease.

Overall Observation of the Patient:

This part is quite important!! You should observe the patient as a whole. They may be talking really fast or appear anxious or even hyper! They may have problems concentrating or remembering what you just said. They may have flight of thoughts and even appear a bit manic. They may be thin if they have lost a lot of weight. They may have eyes which look a little starey or their eyes may even bulge right out.

Conclusion: The thyroid gland is an important part of the body! So please include it on your next physical exam.