Ainhum

What is Ainhum?

Ainhum, also known as dactylolysis spontanea, is a rare health issue where tough, ring-like bindings form at the base of one or more toes. These bands can cause a lot of discomfort and eventual self-amputation of the affected toe. Historically, ainhum is more common in men than women, and it’s found in many different populations, including people of South American, African, White and Indian descent. Originally identified by Silva Lima in 1867, the word “ainhum” comes from the Nago language, meaning “fissure”, or the Yago language, meaning “to saw or cut”.

What Causes Ainhum?

The precise cause of ainhum is not known. However, it is more common in people of African descent, indicating that they might have a genetic tendency to build up too much fibrous tissue in response to injuries or infections.

Pseudoainhum is a similar condition, but it is caused by certain skin conditions or irritations that lead to the growth of a band of fibrous tissue. This can be due to amniotic bands, which are strands of tissue that can wrap around a finger or toe in the womb, or the entanglement of hair or thread around a digit. It can also be caused by an overgrowth of skin in individuals with palmoplantar keratoderma, a skin disorder that causes thick skin on the palms of the hands and soles of the feet.

Risk Factors and Frequency for Ainhum

Ainhum is a condition more commonly found in black males, particularly between the ages of 30 and 50. This condition is seen in 0.015% to 2.2% of the population, with twice as many males affected compared to females. Despite its worldwide presence, ainhum is mainly seen in African countries.

• Ainhum mostly affects black males aged between 30 and 50.
• The condition occurs in 0.015% to 2.2% of the population.
• The disease effects twice as many males as females.
• Although it occurs worldwide, it’s most common in African countries.
• Among white patients, most reports of ainhum are from Brazil, possibly due to mixed ethnic marriages.

Signs and Symptoms of Ainhum

Ainhum, a medical condition, primarily involves the gradual formation of a fibrous ring around the toes or, in rare cases, the fingers. This ring typically forms above the fifth toe and it often occurs on both feet. As the ring gradually tightens, it creates changes in the area of the toe or finger beyond the ring.

The condition is typically identified by three distinct signs:

• A constriction in the soft tissue
• An enlarged area distal to the constriction
• Thinning or disappearance of distal phalangeal bones (the bones in the fingers or toes)

Ainhum progresses through four clear stages:

• The development of a small callus that eventually turns into a circular groove or fissure.
• The area beyond the groove becomes rounded or bulbous, due to the constriction affecting the lymph and venous drainage, narrowing the arteries, and affecting the bone.
• Pain develops as the bone begins to separate, resulting in increased movement of the affected digit.
• Finally, the toe or finger may fall off spontaneously without any bleeding.

Testing for Ainhum

Ainhum, a health condition, is primarily diagnosed through a clinical check-up. At the initial stage, a cut under the toe may not clearly indicate that it is ainhum. The condition is confirmed once there’s the development of a firm ring-like structure. It’s crucial to accurately identify ainhum and not confuse it with a similar condition known as pseudoainhum.

Different imaging techniques are used to determine the stage and extent of ainhum. These can include standard x-rays (radiography), ultrasound, computed tomography (CT scans), or magnetic resonance imaging (MRI).

With the help of radiography, at first, you may notice a dark band at the base of the toe on X-ray images, followed by swelling of the area. Eventually, the damage (known medically as ‘osteolysis’) becomes visible, showing up as a loss of bone matter beyond the dark band. As the condition progresses, the bone keeps narrowing until the toe self-amputates.

Treatment Options for Ainhum

At present, there is no consistent or specific treatment for ainhum as the cause is often unknown. Some intervention methods include using skin ointment and injectable corticosteroids, retinoids, or salicylates to manage mild symptoms. One case suggested that a combination of pimecrolimus cream and low-dose narrowband UVB therapy might aid patients with a psoriasis-triggered pseudoainhum. But it’s important to remember that this treatment worked because it was addressing the underlying cause, which is not always known in ainhum conditions.

Early treatments that aim to reduce the constricting fibrous tissue, similar to treating scars, can be beneficial. Surgery might also be useful to stop the condition progressing – if done early, removing the fibrous band and using a Z-plasty surgical technique can help. If the condition is caught late, the surgical options often involve amputation after bone separation or auto-amputation, which is when the body ‘self-amputates’ the affected part.

What else can Ainhum be?

Ainhum is a condition characterized by the gradual formation of a tight, fibrous ring at the base of the toes or rarely, fingers. This usually occurs on the fifth toe and often on both feet. This fibrous ring typically forms within a crease in the skin, and the area within this ring slowly changes and becomes altered.

The diagnosis of ainhum includes the following key signs in patients:

• Soft tissue that becomes tighter
• Enlargement of the area beyond the tight band
• Thinning or dissolving of the finger or toe bones beyond the band

There are four progressive stages of ainhum, as identified by Cole:

• A small callus or hardened area of skin forms, eventually turning into a tight band or groove.
• The area beyond the band swells up due to restricted lymph and blood flow, along with narrowing of arteries and bone.
• Pain begins as the bone starts to separate, resulting in increased movement of the affected finger or toe.
• The finger or toe finally self-amputates, without bleeding.

Pseudoainhum is similar to ainhum but occurs due to an identifiable skin condition or cause:

Congenital pseudoainhum, amniotic band syndrome or Streeter dysplasia, is believed to be caused by the breaking of the amniotic sac, which constricts developing fetal tissue. It can result in a variety of symptoms, including tight rings, finger or toe amputations, or fusion of the fingers or toes. More severe cases may include malformed brain, limb amputations or conditions resulting from poor lymph flow.

Acquired pseudoainhum develops due to something constricting a finger or toe, such as a hair or thread, or is associated with a hardening and thickening of the skin on the palms of the hands and soles of the feet, or other skin conditions. Conditions that can potentially lead to autoampuation include Vohwinkle syndrome, Olmsted syndrome, Mal de Meleda, loricrin keratoderma, keratosis linearis with ichthyosis congenita and sclerosing keratoderma syndrome, and Papillon-Lefèvre syndrome.

There are also other illnesses and conditions that can lead to the appearance of constricting bands, including leprosy, syphilis, scleroderma, Raynaud syndrome, syringomyelia, diabetes, psoriasis, neuropathic plica, systemic sclerosis, yaws, spinal cord tumors, liver cirrhosis and factitious pseudoainhum from manual strangulation.

What to expect with Ainhum

Ainhum, a medical condition, develops slowly. Usually, it leads to spontaneous amputation about 4 to 6 years after the disease begins.

Possible Complications When Diagnosed with Ainhum

Complications of ainhum, a disease that causes the body’s skin to constrict and sometimes leads to autoamputation of the affected digits, include a range of physical and psychological effects. The physical impacts can include infections, pain, issues with balance, and deformity. On the psychological side, there are often effects due to the physical changes and ongoing pain.

• Secondary infection
• Pain
• Imbalance
• Deformity
• Psychological effects from physical changes and ongoing pain

Recovery from Ainhum

While it’s not officially recorded, some health professionals believe that patients with ainhum or other conditions that cause tightening of the skin could find physical and occupational therapies helpful. Occupational therapy can help improve movement and possibly better fine motor skills after a patient has had an amputation due to the early stages of the disease. If a patient has had either a planned or spontaneous amputation of their toes, physical therapy or custom-made foot supports may help manage walking problems and improve balance.

Preventing Ainhum

Ainhum is a condition where a thin band of tissue forms around the base of a toe or finger, usually the pinky toe. This usually happens to men of African descent between the ages of 30 and 50. Doctors aren’t sure why it happens, but they think that it may have something to do with the genetics of the person.

There are some common signs of ainhum that start showing up in a certain order. The first thing that usually happens is a small groove or split forms under the toe. Over time, the groove gets bigger and might eventually wrap around the entire toe. This can cause the toe to swell due to lymphedema – a condition that causes swelling in the body’s tissues. As the condition progresses, the tissue band might tighten around the toe’s bone and blood vessels, and this could eventually cause a fracture or the affected toe might even fall off by itself.

Managing ainhum is mostly focused on helping the patient manage their pain. In the early stages of the disease, doctors might try to treat the patient with steroid shots or creams, though they’re not sure how well these treatments work. They might also try a surgical technique known as a ‘Z-plasty’ to help ease the tightening around the toe. However, in the late stages of ainhum, amputation of the toe might become necessary.

If the condition is related to another cause, which is known as ‘pseudoainhum’, the patient should try to avoid anything that might trigger the condition and make sure any other diseases they have are being treated properly. But, doctors aren’t sure how to prevent ainhum since they don’t understand why it happens in the first place.