What are hand infections?
Acute infections of the hand are usually bacterial in origin. Due to the rapid progression of the infection, immediate diagnosis and subsequent treatment is very important.
Differentiation between acute vs. chronic infections of the hand
The division between acute and chronic infections is not clearly defined. Infections are often defined in terms of time; infections up to 6 weeks are acute, over 6 weeks are chronic. However, there are also classifications in which an acute infection is max. 1 week and any longer lasting infection is already chronic. It is important to note that initial damage to the joint can occur after just 24 hours.
What are the causes of hand infections?
There are many causes of hand infections. They can generally be divided into two different groups – the exogenous (external) causes and the endogenous (internal) causes.
Exogenous causes
Fingers and finger joints are predestined for cuts, punctures, crushing or bites due to their location. Germs can also get under the skin through punctures in the wrist area. Cortisone infiltration prior to surgery also represents an increased risk factor for postoperative infection. The most frequently occurring bacteria are staphylococci and streptococci (both bacteria normally found on the skin – skin flora), as well as coli bacteria (bacteria found in the intestine – intestinal flora). In young patients, gonococci should also always be considered, as well as fungi in patients with an underlying disease that weakens the immune system.
Endogenous causes
Hematogenous (via the blood) spread is another possibility of a hand infection, e.g. in the case of concomitant inflammation of the heart muscle. Such infection routes via the blood are favored by an underlying disease, e.g. diabetes mellitus, liver and kidney diseases or HIV. In the case of endogenous spread, the wrist is most frequently affected.
What are the symptoms of a hand infection?
Infections of the hand can cause various symptoms.
Panaritium
This is a purulent inflammation of the finger/nail wall. Patients often report a throbbing or pulsating pain. In addition, there is redness and swelling of the affected finger in the area of the nail and a uniform circular pressure pain.
Phlegmon
A phlegmon is an extensive, diffuse, progressive tissue inflammation. This inflammation spreads along the given anatomical structures (e.g. flexor tendon phlegmon). Such inflammations occur most frequently a few days after stab/bite injuries to the palm of the hand. The affected finger is very swollen, painful, overheated, reddened and can only be held in a flexed position. Every stretching movement, whether performed by the patient themselves or by the doctor, can be very painful. In addition to these local findings, there may also be general signs of inflammation such as fever and chills.
Joint empyema
Joint empyema is an accumulation of pus in a joint. Often caused by bacterial arthritis (joint inflammation). Symptoms include severe joint pain and limited mobility. There is also swelling, redness and overheating.
Osteomyelitis
Osteomyelitis is an inflammation of the bone. This occurs when bacteria or fungi penetrate the bone via neighboring infected tissue, open wounds (see chapter “Chronic wounds”) or, more rarely, via the bloodstream and infect it. Patients often have pain in the area of the affected bone and a fever.
How is the diagnosis made?
Each examination begins with a detailed medical history (questioning) of stab/bite injuries and previous interventions, punctures or injections in the area of the affected finger or wrist. Risk factors and concomitant illnesses are also investigated. During the clinical examination, the doctor will look for pain, redness, swelling and restricted movement. All these clinical signs can be present in varying degrees.
A conventional X-ray is taken to visualize the bone, the joint and any remaining foreign bodies. An ultrasound examination can also be carried out. MRI and CT are not the method of choice for acute infections, but are frequently used for chronic infections and bone infections.
In a blood test, inflammation values such as leukocytes (white blood cells) and CRP (inflammation marker) may be elevated. However, it is also possible that these values are normal, but this does not rule out inflammation.
How is an infection of the hand treated?
If an infection is detected very early, it may still be possible to treat it conservatively, i.e. without surgery. If the infection is already advanced, the only treatment option is surgical treatment.