Nail Clubbing sometimes called as “Hippocratic fingers”, “clubbing of fingers” or “digital clubbing” is the change in angle between the nails and the nail base. The first recorded incident was during the Greek Era by the Father of Medicine, Hippocrates of Kos around 460 t0 370 BC. People who manifested the disease have upper and lower extremities that are deformed with fingertips that are wider and rounder than usual. It is eventually larger than 180 degrees and is sometimes characterized by softening of the nail beds with flattening of the nails and sometimes enlargement of the fingertips. Normally, the nails are transparent, smooth, well-rounded and convex with a nail bed angle of about 160 degrees. Clubbing of fingers is often an underlying symptom of a congenital cardiovascular disease or a heart ailment.
Grades of Nail Clubbing
There are five different grades of digital clubbing, some stages have visible changes while others have moderate to drastic changes.
- The first stage has zero signs of nail bed altercations. However, in this stage the nail bed starts to soften and slowly fluctuates.
- The second stage is mild clubbing. In this stage, there is absence of the normal Lovibond angle but it can only be appreciated upon closer look.
- The third stage is the moderate clubbing phase where the convex between the folds of the nails are dramatically increased and fingertip malformation is less palpable.
- Meanwhile, the fourth stage is the phase where digital clubbing is appreciated even at quick glance. During this stage, the tips of the fingers are slowly beginning to show a curve on each side and the nails begins to widen resembling like that of a chicken leg.
- Lastly, the fifth stage is the Hypertrophic Osteoarthropathy where on top of an apparent digital clubbing, extremities have also increased in size. This resembles so much like that of a “bird claw” but is wider in diameter. The angles of the nail beds are greater than usual. In addition, patients would also experience angle and joint swelling.
Consequently, these stage has two types: Primary and Secondary. The former is genetic and is often credited to an autoimmune disorder while the latter is sometimes an underlying symptom of a malignant infection.
Nail Clubbing Test
Doctors determine the condition by asking the patients to complete a test called “Schamroth’s Window Test” or also known as “Schamroth’s Test”. The procedure was formulated by a South African doctor Leo Schamroth. It is so popular that it became the definitive test for clubbing of fingers.
Normally, a small diamond shaped window is visible between the nail bed and the nail folds. However, if it looks obliterated or blotted out, this may confirm existence of the disease. In addition, the nail beds also become soft and spongy, the distal part of the fingers are thickened, reduced Lovibond angle is observed and increased convex in the nail folds are also apparent in patients who tested positive.
Causes of Nail Clubbing
Etiology of this rare condition remains unclear but medical researchers believe that it is prevalent with race and genetic predisposition. Also, it is often associated with undiagnosed pulmonary, cardiovascular, neoplastic infections, as well as hepatobiliary, mediastinal, endocrine, and gastrointestinal diseases. It may also occur as an idiopathic form that is most common in males with inherited autosomal and recessive X-linked trait, this is common in some families with PDP (pachydermoperiostosis). Furthermore, lung cancer or heart defects is the common cause of clubbing as it often occurs in the heart and the lungs where hypoxia occurs (reduced amount of oxygen in the blood).
Inflammation in the lining of the heart and heart valves caused by bacteria, fungi and other infectious substances can also expose someone of getting the disease. Liver Cirrhosis, celiac disease, diarrheal infections, hyperthyroidism, Hodgkin’s lymphoma can be a causative factor as well. Additionally, medical articles also describe rare skin conditions including pachydermoperiostosis and palmoplantar keratoderma as unusual causes of nail clubbing.
Other common causes of clubbing are Pulmonary Fibrosis, a condition that presents stiffening and scarring of the lung. Bronchiectasis can also be attributed to the cause of the disease as it is an illness where bronchial tubes are permanently damaged and widened and when this happens, less oxygenation of the blood occurs contributing to clubbing of the nails.
Additionally, Tetralogy of Fallot is the most common cause of clubbing. It is named after Dr. Etienne Fallot, who discovered that a congenital heart defect can be fatal when left untreated. The condition causes cyanosis due to the lack of circulating oxygen which is manifested through pale nail beds contrary to the normal pink toned beds. Although it is rare, it is the common cause of cyanotic heart disease.
Clubbing develops first in the thumb and forefinger before it eventually spreads to the other fingers. Obliteration in the angles of the nail beds is the first clinical sign and constant feature of the disease. Common symptoms of clubbing include softening of the nail beds. Instead of being firmly attached, the nails may seem to float. They form a sharper angle with the cuticle and the fingertips may look like it is swollen and bulging. In addition, curvature of the nails pointing downward similar to that of an upside-down spoon often called as “koilonychia” wherein the fingertips appear more broad and round than usual often suggests blood work-up for hemochromatosis or anemia. For lower extremities, clubbing of the toes is difficult to determine as they normally appear bulbous but is often recognizable in the great toe. In mild cases though, minimal changes of the toe and slight pain are sometimes expressed by patients.
Oftentimes, changes in the color of the nails suggests systemic conditions such as hepatic failure and diabetes for unusually white nails, renal failure for half and half nails, arsenic poisoning for prevalent Mee’s line, dark longitudinal streaks for melanoma and chemical staining while longitudinal striations suggests alopecia areata or hair loss and sometimes psoriasis or vitiligo. Furthermore, brown or black discoloration and striations of the nails may suggest presence of early stage HIV.
Diagnostic studies for nail clubbing are usually laboratory blood work-ups that confirm the underlying conditions but not the disease itself.
- Imaging studies can also be suggested by physicians to diagnose the presence of such conditions. Firstly, X-ray is used to check evident presence of bone dissolution and bone deformation.
- Secondly, Technetium Tc 99m Skeletal Imaging can also be recommended as it helps in providing good quality views in determining the extent of bone changes in clubbed digits, this also shows increased levels of blood flow and softening of surrounding tissues.
- Thirdly, Thermography is another imaging test used to monitor increased temperature in the distal digits of patients testing positive for clubbing as this suggests vasodilation, however, not all clubbing have positive results.
- Fourthly, Positron emission tomography is used to study glucose metabolism of clubbed digits as increased signals indicates higher glucose metabolism which is often demonstrated in distal parts of the clubbed fingers. These signs aren’t apparent in normal fingers, however, increased signal levels supports the study that clubbing is attributed to platelet derived growth factor which increases metabolism.
- Lastly, Computed Tomography ( CT Scan) or Magnetic Resonance Imaging (MRI) aids in evaluating the primary causative factor of clubbing. When high frequency ultrasound imaging is used, Primary Hypertrophic Osteoarthropathy is easily presented in the films showing the long bones surrounded by echogenic tissues,this presentation reflects edematous and inflamed tissues which is a confirmative sign of the condition.
Can Nail clubbing be Reversed?
Although clubbing is irreversible, early detection and treatment can potentially decrease the deformity or even reverse it if treated abruptly the moment it is diagnosed. However, reversal is unlikely the moment depositions of collagen are increased. Consequently, palliative treatment or symptomatic treatment is available.
Researchers have recorded that some patients respond well to Etoricoxib (Arcoxia), a non-steroidal, anti-inflammatory drug often called as NSAIDs. It soothes the pain and swelling and is taken once a day on a full stomach. However, Etoricoxib does not work well with patients who are suffering from asthma and other allergic disorders, duodenal ulcers, hypertension, diabetic patients, clients with clotting problems or even patients suffering from diarrhea. The drug is often available in four preparations: 30 mg, 60 mg, 90 mg and 120 mg. Doctors often prescribed the safest or the lowest dose for a short period of time to lessen the risk of adverse effects.
In addition, there are also known natural remedies for nail clubbing. Some of the conservative treatments are:
- A mixture of 3 tablespoons of olive oil and one tablespoon lemon juice in a small bowl wherein clubbed nails are soaked in the mixture for 10 minutes is known to straighten clubbed nails
- Soaking clubbed nails in a mixture of tomato juice, lemon juice as well as olive oil in a small bowl
- Application of warm olive oil can also treat the condition
- Sliced lemons rubbed over the nails in a 5 minute period also promotes natural nail growth
- Consumption of foods rich in gelatin such as jellies can also be a cure as well
- Avoidance of eating Vitamin E rich foods such as jojoba oil, wheat germ oil, almond oil and the like
- Drops of Tea tree oil on the nail beds as well as use of essential oils
- Salt water treatment for 5 minutes on the nail beds
- Consumption of green leafy vegetables on a regular basis
- No cutting of cuticles
Overall, nail clubbing can be prevented by consistent hand hygiene and practicing a healthy and well-balanced lifestyle.