Hypothenar Hammer Syndrome

HHS Meanings

Hypothenar Hammer Syndrome (HHS for short according to abbreviationfinder) is an arterial disorder of blood flow in the hand. It is caused by a blunt force impact that is applied once or repeatedly to the ball of the little finger (the hypothena). This force usually injures the ulnar artery that triggers the HHS.

What is Hypothenar Hammer Syndrome?

Typical signs and symptoms that accompany Hypothenar Hammer Syndrome are a feeling of numbness, weakness and coldness in the entire hand or just in the area of ​​the ball of the little finger.

Medicine speaks of hypothenar hammer syndrome when the ulnar artery has been injured by a blunt force and there is an arterial circulatory disorder in the hand as a result. The ulnar artery is located in the ball of the little finger. The syndrome occurs remarkably often in craftsmen and workers who use their hand in a striking manner and thus like a striking tool.

In this case, the heel of the hand is used as a substitute for the hammer, which promotes injury to the ulnar artery. For this reason, however, martial artists can also suffer from hypothenar hammer syndrome. HHS has been treated as an unofficial occupational disease by professional groups such as craftsmen for years. Officially, however, the HHS has not yet been able to assert itself as such.


Since hypothenar hammer syndrome is caused by an injury to the ulnar artery, a typical cause of HHS is external trauma to the thenar eminence. As a result, HHS can have many causes: for example, an accident in which the bunions and thus the ulnar artery are injured.

HHS occurs particularly frequently when the heel of the hand is repeatedly used as a striking tool. Therefore, craftsmen and athletes (e.g. martial artists) are often affected by HHS – however, cases are also known where HHS occurred after a single act of violence on the ball of the little finger.

Symptoms, Ailments & Signs

Typical signs and symptoms that accompany Hypothenar Hammer Syndrome are a feeling of numbness, weakness and coldness in the entire hand or just in the area of ​​the ball of the little finger. In addition, there is often stabbing, permanent or recurring pain in the hand affected by HHS. The severity of the symptoms and complaints usually depends on the severity of the injury at hand.

In addition, the symptoms can also appear a few days, weeks or even months after the actual trigger for the injury. In many cases, the pain subsides a short time after the injury, or the pain and discomfort is so minor that people do not consider the injury severe enough to seek medical attention.

There are also many patients who show no symptoms or complaints at all. This is mostly due to the fact that the blood vessels in the hand are not only supplied by the ulnar artery, but also by the radial artery – and this does not show any injuries in HHS. For this reason, the syndrome is still considered a relatively rare clinical picture, although the number of unreported cases can be very high.

Diagnosis & course of disease

In most cases, those affected only seek medical attention if they have symptoms. Depending on the severity, the present clinical picture can be acute or less acute. Especially if the ball of the thumb was injured a long time ago, most of those affected can often no longer assign the symptoms to it.

There are also numerous other diseases, such as the nerve tracts in the hands, which can cause similar symptoms and complaints. Therefore, the doctor will always first have to find out whether an injury could be responsible for the symptoms. If this is evidently the case or if the person concerned knows it, he will initiate the appropriate further diagnostic steps.

If the cause seems unclear, it is primarily up to the doctor to make the correct diagnosis. In most cases, this is based on the existing complaints and symptoms, through discussions with the patient and with the help of different examination results, to narrow down what the cause of the complaints could be. Only when this is clear can the actual treatment begin. The course of HHS also depends on factors such as the severity of the injury to the artery and, not infrequently, the length of time the syndrome has gone undetected.


Hypothenar hammer syndrome usually leads to a restriction of blood flow in the hand. The reduced blood flow can lead to various symptoms and complications. As a rule, however, the further course of the disease depends on the length and severity of the trauma to the hand. Not in every case there is a positive course of the disease.

The patient suffers from numbness and often tingling on the hand. These feelings can lead to limitations in everyday life. It is not uncommon for pain to spread from the hand directly to other regions. If the pain also occurs at night in the form of rest pain, it can lead to sleep disorders. In severe cases, the tissue can be so severely damaged that amputation is necessary.

Muscles and nerves can also be damaged by a lack of oxygen. The treatment is carried out with the help of medication and, if necessary, with surgical interventions. However, it cannot be ruled out that consequential damage will occur that is irreversible and therefore cannot be treated. Life expectancy is usually not affected by Hypothenar Hammer Syndrome.

When should you go to the doctor?

In some cases, hypothenar hammer syndrome causes no symptoms. A medical examination is then useful, but not absolutely necessary. As soon as symptoms are noticed, medical advice is required. If there is numbness and weakness in the area of ​​the ball of the thumb, it may be due to hypothenar hammer syndrome. The syndrome should be quickly clarified and treated by a doctor to avoid complications. If there is stabbing pain, a doctor should be consulted on the same day.

If the symptoms can be traced back to an accident or another cause, you must also go to the doctor promptly. However, the symptoms can also appear days, weeks or months after the actual trigger. That is why those affected should always speak to a doctor after an accident or fall, even if there are no noticeable symptoms or signs of injury. Craftsmen, martial artists, cyclists and other groups of people who put excessive strain on the heels of their hands are particularly susceptible to the development of the syndrome – these risk groups should contact their family doctor quickly if they experience the symptoms mentioned. In the case of pronounced circulatory disorders, an internist can be consulted.

Treatment & Therapy

Treatment depends on the severity of the injury and any consequential damage. Because the longer the HHS remains undetected and has not been treated, the greater the risk that the vessels, tissue, muscles and nerves in the area of ​​the ball of the thumb that are affected by the present arterial circulatory disorder will be damaged by a possible undersupply.

Depending on the case, different treatment steps could be necessary – both medicinal and surgical steps, in severe cases, are possible. In addition, the injured hand or the hand affected by the HHS should be protected. However, the chances of success of the treatment are still very different. In most cases, the sooner the injury and thus also the HHS is recognized, the better the chances of treatment. But there are also many cases in which those affected complain of more or less severe symptoms for the rest of their lives.


HHS can be prevented if the heel of the hand is not used as a striking tool. And: If this is done and there is an injury or symptoms that indicate HHS, then a doctor should be consulted immediately.


In most cases, patients with hypothenar hammer syndrome have no special and direct options for aftercare. Therefore, those affected are primarily dependent on a quick diagnosis and also on further treatment of the disease in order to prevent further complications or symptoms. The symptoms of hypothenar hammer syndrome cannot always be completely alleviated.

First and foremost, the force on the affected area must be stopped so that the tissue and arteries are not damaged even more. A doctor should be consulted immediately if circulatory disorders or sensitivity disorders occur, so that the disease can be recognized and treated quickly.

In some cases, patients with Hypothenar Hammer Syndrome also depend on the help and support of friends and family in their everyday life. In the case of mental upsets or depression, contact with loved ones is often useful to alleviate them. Contact with other people affected by Hypothenar Hammer Syndrome can also be useful. As a rule, the patient’s life expectancy is not reduced by this disease.

You can do that yourself

First and foremost, the patient with hypothenar hammer syndrome must stop the force on the affected region of the body immediately and also avoid it in the further course. This can limit further complications and complaints. However, treatment by a doctor is essential, as this can lead to permanent damage to the nerves or blood vessels. The sooner treatment is initiated, the higher the chances of a complete cure for Hypothenar Hammer Syndrome.

However, those affected are also dependent on various therapies after surgical interventions, which are intended to restore the mobility of the fingers and hand. Most of the exercises can also be carried out at home, so that mobility is trained again. Occupational therapy or physiotherapy is particularly suitable for this. The exercises can also be continued at home and thus contribute optimally to the recovery process.

The ball of the thumb itself should generally never be used as a striking tool, as this can very quickly lead to serious injuries. Children and young people in particular must be informed about this danger in order to avoid injuries. In the case of a serious and acute injury, the hospital can also be visited.

Hypothenar Hammer Syndrome