Hypothenar Hammer Syndrome: Causes, Symptoms & Treatment

Hypothenar hammer syndrome (HHS for short ) represents an arterial disorder of blood flow to the hand. It is caused by blunt force trauma, either single or repetitive, to the ball of the little finger (the hypothena). This force usually injures the ulnar artery, which triggers the HHS.

What is hypothenar hammer syndrome?

Medical science refers to hypothenar hammer syndrome when the ulnar artery has been injured by blunt force trauma and, for this reason, there is an arterial blood flow problem in the hand. 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 percussive manner and thus like a percussion tool. In this case, the ball of the hand is used as a substitute for a hammer, which favors an injury to the ulnar artery. For this reason, however, martial artists can also suffer hypothenar hammer syndrome. For years, HHS has been treated as an unofficial occupational disease of occupational groups such as craftsmen. Officially, however, HHS has not yet been able to establish itself as such.

Causes

Because hypothenar hammer syndrome is caused by injury to the ulnar artery, a typical cause of HHS is external force to the ball of the little finger. As a result, HHS can have many causes: for example, an accident that injures the ball of the finger and thus the ulnar artery. HHS is particularly common when the ball of the hand is used repetitively as a striking tool. Therefore, craftsmen and athletes (such as martial artists) are often affected by HHS – however, there are also known cases where HHS occurred after a single violent impact on the ball of the little finger.

Symptoms, complaints, and signs

Typical complaints and symptoms that accompany hypothenar hammer syndrome include a feeling of numbness, loss of strength, and coldness in the entire hand or only in the area of the ball of the little finger. In addition, there is often stabbing, persistent or recurrent pain in the hand affected by HHS. The severity of the symptoms and discomfort usually depends on the severity of the injury at hand. In addition, the symptoms may well occur several days, weeks or even months after the actual trigger for the injury. In numerous cases, the pain subsides after a short period of time following the injury, or the pain and discomfort is so minor that the individual does not consider the injury drastic enough to seek medical attention. Likewise, there are many patients who show no symptoms or discomfort at all. This is usually because the blood vessels of the hand are supplied not only 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 condition today, although the number of unreported cases may be very high.

Diagnosis and course of the disease

In most cases, those affected only seek medical attention when symptoms are present. Depending on the severity, the presenting clinical picture may be acute or less acute. Particularly if the injury to the little finger ball has been present for some time, most of those affected are often no longer able to identify the symptoms. In addition, there are numerous other diseases, for example of the nerve tracts in the hands, which can cause similar symptoms and complaints. Therefore, the doctor will always have to find out first whether an injury could be responsible for the complaints. If this is obviously the case or known to the person affected, he will initiate the appropriate further diagnostic steps. If the cause seems unclear, it is primarily up to the doctor to actually make the correct diagnosis. In most cases, he or she will narrow down what the cause of the complaints could be on the basis of the complaints and symptoms present, through discussions with the patient and with the help of various examination results. Only when this is clear can the actual treatment begin. The course of the HHS disease 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 undiagnosed.

Complications

Usually, hypothenar hammer syndrome results in restriction of blood flow in the hand.The reduced blood flow can lead to various complaints and complications. As a rule, however, the further course of the disease depends on the length and severity of the force exerted on the hand. Not in every case there is a positive course of the disease. The patient suffers from numbness and often tingling sensations on the hand. These feelings can lead to restrictions 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 pain at rest, this can lead to sleep problems. In severe cases, the tissue can be damaged to such an extent that amputation is necessary. The muscles and nerves can also be damaged by an undersupply of oxygen. In such cases, treatment is carried out with the aid of medication and, if necessary, surgical intervention. However, it cannot be ruled out that consequential damage occurs that is irreversible and therefore cannot be treated. Life expectancy is usually not limited by hypothenar hammer syndrome.

When should you see a doctor?

In some cases, hypothenar hammer syndrome does not cause symptoms. Medical clarification is then useful, but not absolutely necessary. As soon as symptoms are noticed, medical advice is needed. If numbness and lack of strength occur in the area of the little finger ball, hypothenar-hammer syndrome may be the cause. The syndrome should be clarified and treated quickly by a doctor to avoid complications. If stabbing pain occurs, a doctor should be consulted the same day. If the symptoms can be attributed to an accident or another cause, a doctor should also be consulted promptly. However, the symptoms may not appear until days, weeks or months after the actual trigger. That is why those affected should always talk to a doctor after an accident or fall, even if there are no noticeable complaints 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 consult their family doctor quickly if they experience any of the symptoms mentioned. In the case of pronounced circulatory disorders, an internist may be consulted.

Treatment and therapy

Treatment depends on the severity of the injury present and any subsequent damage. This is because the longer HHS remains undiagnosed and untreated, the greater the risk that the vessels, tissues, muscles, and nerves in the area of the ball of the little finger affected by the present arterial circulatory disorder will be damaged by possible insufficient blood supply. Depending on the case at hand, various therapeutic steps could become 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 spared. However, the chances of successful treatment still vary considerably. In most cases, the sooner the injury, and thus the HHS, is recognized, the better the chances of treatment. However, there are also many cases in which those affected complain of more or less severe symptoms for the rest of their lives.

Prevention

HHS can be prevented if the ball of the hand is not used as a striking tool. What’s more, if it is, and there is an injury or discomfort that points to an HHS, then a doctor should be consulted immediately.

Follow-up

In most cases, patients with hypothenar hammer syndrome have no specific or direct options for follow-up care. Therefore, affected individuals are primarily dependent on a quick diagnosis and also on further treatment of the disease to prevent further complications or discomfort. In doing so, it is not always possible to completely alleviate the symptoms of hypothenar hammer syndrome. First and foremost, the force applied to the affected area must be stopped to prevent further damage to the tissue and arteries. A doctor should be consulted immediately if disturbances of blood flow or disturbances of sensibility occur, so that the disease can be recognized and treated quickly.In some cases, hypothenar hammer syndrome also makes patients dependent on the help and support of friends and family in their daily lives. In cases of psychological upsets or depression, it is not uncommon for contact with loved ones to be useful in alleviating them. Contact with other hypothenar hammer syndrome sufferers can also be useful in this regard. Usually, the patient’s life expectancy is not reduced by this disease.

What you can do yourself

First and foremost, the sufferer of hypothenar hammer syndrome must immediately stop the use of force on the affected region of the body and also avoid it as it progresses. This can limit further complications and discomfort. However, treatment by a doctor is essential, as this can cause permanent damage to the nerves or blood vessels. The earlier treatment is initiated, the higher the chances of a complete recovery from hypothenar hammer syndrome. However, even after surgical interventions, those affected are dependent on various therapies that are intended to restore the mobility of the fingers and hand. Most of the exercises can be done at home, so that the mobility is trained again. Occupational therapy or physiotherapy is particularly suitable for this. The exercises can also be continued at home and thus contribute to the recovery process in the best possible way. As a rule, the ball of the hand itself should never be used as a striking tool, as this can very quickly lead to serious injuries. Children and young people in particular must be made aware of this danger in order to avoid injury. In case of a serious and acute injury, the hospital can also be visited.