- occurs in several seemingly unrelated conditions - deep-red erythema over the thenar and hypothenar areas
Causes of Palmar erythema
Results from deep telangiectasias and is commonly associated with chronic liver disease and pregnancy
Why does palmar erythema occur with both chronic liver disease and pregnancy?
- Because circulating levels of estrogen increase in both cirrhosis and pregnancy - estrogen was thought to be the cause for the increased vascularity - More recently, nitric oxide has been implicated in the pathogenesis of palmar erythema
Hands: Bony Structures
Hands: Bony Structures
How does gender affect finger length?
- In most males, the ring finger is longer than or the same length as the index finger - In most females, the index finger is longer than or the same length as the ring finger
- congenital end-organ unresponsiveness to parathyroid hormone - can be suspected from examination of the hands
What are physical exam findings of Pseudohypoparathyroidism?
- 4th and 5th fingers are shorter than normal due to shortening of metacarpals - Patients usually have round faces, short stature and developmental delay as well - When patient makes a fist, the 4th and 5th knuckles are not visible
What is elongation of the fingers called?
arachnodactyly (spider fingers)
What is arachnodactyly a feature of?
What signs help differentiate the slender digits of Marfan's patients from the digits of thin patients?
A positive thumb sign (Steinberg's sign) and wrist sign
When is the thumb sign positive?
When the fingers are clenched over the thumb, the end of the thumb protrudes beyond the hypothenar eminence
When is the wrist sign positive?
When the patient encircles his/her own wrist with the thumb and little finger just proximal to the styloid process of the ulna, the thumb and little finger overlap by 1-2 cm
Finger Nails: Normal nail anatomy
Finger Nails: Normal nail anatomy
What is the paronychia?
The soft tissue surrounding the nail border
What is the eponychium?
The stratum corneum layer of skin covering the nail root - It is also called the cuticle
Are the fingernails important on physical exam?
Yes, they contain a wealth of diagnostic information on physical exam.
How fast do fingernails grow? Toenails?
- About .1 mm per day and take about six months to grow from base to tip - Toenails grow somewhat slower
What can the thumbnail provide a clue to? Why is this important?
- provide a clue to dominant handedness - could be of value when trying to predict the prognosis for rehabilitation of a comatose patient with a neurologic deficit
What features does the dominant thumbnail typically have?
- a wider base - the angles formed by the base and the lateral aspects of the nail are usually more obtuse
What does inspection of a normal nail from the side reveal?
- that the nail forms an angle (Lovibond's angle) with the skin just proximal to the nail - this angle normally measures about 150
What is clubbing?
Painless enlargement of the terminal phalanges
What causes clubbing?
It results when the nail bed overgrows and pushes the proximal nail upward
How long does it take clubbing to develop or resolve?
Clubbing may develop or resolve within as little as ten days
What does clubbing do to Lovibond's angle?
It increases Lovibond's angle to > 190 degrees
What does clubbing also increase?
It increases the interphalangeal depth ratio to > 1.0
What is the interphalangeal depth ratio? What is it normally?
- When examined from the side, it is the ratio of the digit's depth at the proximal nail fold to the depth at the middle of the distal interphalangeal joint (the interphalangeal depth ratio) - It is normally < 1
How else can clubbing be detected?
By looking for Shamroth's sign
What is Shamroth's sign?
- Clubbing abolishes the small diamond (Shamroth's sign) - In the absence of clubbing, placing the terminal phalanges of the corresponding fingers back to back forms a small diamond shaped window
What does applying pressure to the proximal nail bed due in a patient with clubbing? How is this simulated in a normal nail?
- It elicits a spongy or floating quality - This can be simulated in a normal nail by palpating over the proximal nail while at the same time pushing on the distal nail with the opposing thumb
What disease does clubbing occur in? (there are 7)
1. Cyanotic congenital heart disease 2. Cancer of the lung or pleura 3. Lung abscess 4. Bronchiectasis 5. Ulcerative colitis 6. Hyperthyroidism 7. Cirrhosis
What is clubbing most likely due to?
Clubbing develops when platelet aggregates and megakaryocytes become trapped in the distal digits and release a variety of platelet-derived growth factors that stimulate tissue proliferation
Pain in what area is sometime associated with clubbing?
Pain in the shafts of the distal long bones secondary to periosteal new bone formation
When clubbing and periosteal new bone formation occur what exists?
What is hypertrophic osteoarthropathy an important manifestation of?
bronchogenic squamous cell carcinoma
Describe Mees' nails
Mees' nails have a single transverse, white band that runs the width of the nail plate, seen on multiple nails
What causes Mees' nails?
- arsenic poisoning - more commonly seen as a result of serious illness such: >sepsis >acute renal failure >sickle cell crisis >myocardial infarction >any severe physical or emotional shock
What happens to the white bands during growth in people with Mees' nails?
They move distally during nail growth
Describe Beau's Line
- Probably a more serious form of Mees' nails - characterized by the presence of one or more transverse ridges in the nail plate
What does Beau's Line result from? What happens to it during growth?
- Beau's lines result from similar conditions as Mees' nails - Beau's lines move distally with nail growth
Describe Nail pitting and what it occurs from
- It is a growth disturbance of the nail plate that occurs in psoriasis - Also develops in normal individuals due to focal trauma to the nail plate
Describe Lindsay nail
- also called a half and half nail - the proximal portion of the nail bed is white and the distal portion of the nail bed has a red, pink, or brown color
When does Lindsay nail occur?
In patients with renal failure or chronic hepatic failure
Describe Terry's nail
The proximal three-quarters of the nail bed is pale and the distal one quarter is pink or red. (three quarter/one quarter nail)
When does Terry's nail occur?
- in patients having chronic hepatic cirrhosis - also been seen in a wide variety of other conditions including: >hypoalbuminemia >connective tissue diseases (rheumatoid arthritis) - juvenile diabetes mellitus - pulmonary TB
Describe the second type of nail described by Terry and when it occurs
- The lunula has a deep red color and the remainder of the nail is paler than normal - Over half of patients with this finding have congestive heart failure
Describe Muehrcke's lines
Paired, white, transverse, parallel bands appear in the nail bed against a normal pink background
What happens to the white bands during growth in people with Muehrcke's lines?
Since the white bands are not in the nail plate, they do not move distally with nail growth
When do Muehrcke's lines form?
during episodes of hypoalbuminemia (albumin levels < 2 gm/dl)
Describe Leukonychia punctata
White spots in the nail plate which occur from minor injury or manipulation of the nail plate
What happens to Leukonychia punctata with time?
They resolve spontaneously or grow out with the nail
Longitudinal ridging of the nails, a common feature of old nails. It may also be seen in radiation damage
What should Onychorrhexis not be confused with?
pigmented bands in the nail beds of dark skinned individuals (not palpable)
Separation of the nail plate from the nail bed at its distal and lateral attachments is termed onycholysis. The mechanism is unknown
When does Onycholysis occur?
In patients with: - hyperthyroidism - psoriasis - fungal infections of the nail - phototoxic drug reactions
Describe Spoon nails (kloilonuchia)
normal convexity of the nails is replaced by concavity
When do spoon nails occur?
occurs in hypochromic anemia and iron deficiency
Describe yellow nail syndrome
Thickened yellow nails
When does yellow nail syndrome occur?
In the presence of: - exudative pleural effusion, an underlying lung carcinoma must be excluded - lymphatic obstruction
What does onychomycosis refer to?
nail infections caused by any fungus
What are characteristics of onychomycosis?
Nail changes that include thickening of the nail, with yellowish or white discoloration distally, due to hyperkeratotic debris accumulation
What distinguishes onychomycosis from psoriasis?
Absence of pitting
How many of the toenails/fingernails are involved?
One or several, it is rare for all nails to be involved
What makes patients seek medical attention for onychomycosis?
Most patients are concerned for cosmetic reasons, but some have associated pain
Describe splinter hemorrhages
Linear red hemorrhages (splinters) run longitudinally in the nail bed from the free margin proximally
When are splinter hemorrhages common?
In people who engage in manual labor
What do splinter hemorrhages sometimes occur with?
infectious endocarditis and to a lesser extent in those with trichinosis
Splinter hemorrhages are probably...
...vasculitic in nature
What does Paronychia refer to?
inflammation of the paronychium (skin around nail)
How does Paronychia occur?
- Bacteria invade between the nail fold and nail plate - This can be acute or chronic
Describe the appearance of Paronychia
Redness, swelling and tenderness are seen at the lateral and proximal nail folds. Purulent drainage may occur under the cuticle (eponychium)
When do ingrown nails occur?
when the nail pierces the lateral nail fold and grows into the dermis
What causes ingrown nails?
poorly fitting shoes, or excessive trimming of the lateral nail plate
Symptoms of ingrown nails?
Redness and swelling are seen at the area of nail penetration
What nail is most commonly involved in ingrown nails?
Nail of the large toe
What causes subungual hematoma?
trauma to the nail plate causing bleeding and severe pain
How long will the hematoma remain?
until the nail grows out or is decompressed to release the blood and relieve the pressure
What significantly reduces pain of a subungual hematoma?
What must subungual hematoma be distinguished from?