Introduction
The five metacarpals (Ossa metacarpalia) are located between the eight bones of the wrist and the three phalanges of the respective fingers (the thumb consists of only two phalanges). They can in turn be divided into three sections, a so-called base (which is connected to the carpal bones), a bone body (corpus) and a head (caput), which is the furthest from the body. The bone heads are visible as an ankle on the back of the hand.
In the area of the metacarpals, painful sensations can occur for various reasons. Depending on the cause, the pain can be burning, stinging, dull, pressing or tingling. Furthermore, a distinction can be made between permanent (chronic) and acute pain.
Causes
Pain in this area can have bony causes, such as a broken or sprained metacarpal. In rare cases there may also be a space-occupying process in this bone, such as a bone cyst, bone tumor or bone metastasis. But muscles or tendons in the area of the metacarpus can also be the starting point for pain.
This can also simply be an expression of acute overloading or incorrect loading of the hand. A nerve running along there can be irritated, inflamed or pinched and thus also cause pain. Joints adjacent to the metacarpals can also be painful in the case of rheumatism, gout or general signs of wear and tear (arthrosis).
As a result of trauma to the hand, metacarpals can also break. Mostly this happens in the context of a fall, during sports or due to a punch. A distinction is made between displaced (dislocated) and still correctly standing bone ends.
This fracture can also be open, i.e. visible in the wound, or closed. Such a fracture is either immobilized in a plaster cast for a few weeks or, in the case of more complicated fractures, straightened in an operation and treated with a plate or nail, for example. The sheathing of a tendon can become inflamed, especially in the area of the hand (tendovaginitis).
This can happen in chronic, one-sided strain, such as when working at a desk, can occur in connection with rheumatism or can rarely be caused by bacteria or other pathogens. The pain then occurs when the hand is moved, swelling of the affected area may occur, and palpable grinding or rubbing sensations caused by nodular changes in the affected tendon sheath may occur. First of all, it is important to protect the affected hand.
Cortisone can also be injected into the tendon sheath to combat the inflammation. If the symptoms cannot be treated in this way, surgery may be necessary. This involves splitting the tendon sheath lengthwise to relieve the tendon.
This phenomenon is also called “fast finger“, the technical term is “tendovaginitis stenosans”. This form of inflammation is also caused by overloading, which leads to small tendon injuries and swelling, which in the long run turn into knotty changes of the tendon. These knots must pass through the ring ligaments, which also regularly surround the tendons.
This often happens in the area of the first (body near) ring ligament of a finger, so that first this resistance must be overcome with more force. Once a certain degree of force has been reached, the tendon suddenly slides through and the finger “snaps” into the flexion, for example. Overall, this makes stretching and bending the finger increasingly painful.
The metacarpals, as well as the wrist and the wrist as a whole, are often affected by injuries from falls and blows. As an injury close to the wrist, the forearm fracture is the most common fracture in humans, but the metacarpals can also be affected by compressions, bruises, fractures and joint damage. Typical causes of accidents are support traumas or punches.
Depending on the angle of the injury and the violent impact, bruises, simple fractures or comminuted fractures may occur. Typical triggers are also ball sports such as basketball or volleyball, where blows to the metacarpals are common. In the acute phase after the injury, the hand must be cooled, elevated, protected and stabilized with a pressure bandage. This will reduce bruising and swelling, and the potentially injured bone can be splinted.On the basis of an x-ray image taken by the doctor, a fracture of the metacarpal bones can be diagnosed. A bruised metacarpal only needs to be spared, whereas a broken bone often has to be surgically screwed together so that the hand remains stable against stress in the long term.
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