Nerves

The femoral nerve from the lumbar plexus sensitively innervates the medial side of the knee joint and the medial side of the lower leg up to the ankle joint. The sciatic nerve from the sacral plexus divides into its two main branches at the level of the hollow of the knee: The common fibular nerve sensitively innervates the lateral skin of the lower leg. It divides itself again into two branches.

The superficial fibular nerve motorically innervates the peroneal longus and brevis muscles. In addition, it sensitively supplies the skin of the entire back of the foot. The nervus fibularis profundus supplies all extensor muscles of the lower leg by motor.

It also sensitively innervates a small skin area between the first and second toe. The tibial nerve supplies the gastrocnemius muscle with motor power. In its course, the tibial nerve gives off a few small branches that innervate numerous muscles of the lower leg.

In addition, some branches supply the heel area sensitively. Another branch supplies the tibial nerve. This branch also supplies the interdigital space of the toes.

Common fibular nerve and
Tibial nerve.
Musculus abductor hallucis, the
Musculus flexor digitorum brevis and the
Musculus flexor hallucis longus.

Diseases of the lower leg

Lower leg thromboses are based on a blood clot in the arteries or veins, which massively restrict the blood flow. The following symptoms are: Often the superficial veins also become more prominent and are now clearly visible. The symptoms mentioned above are not proof of thrombosis, nor does the absence of a symptom rule out thrombosis.

The risk of thrombosis in the lower leg is the blockage of a pulmonary artery (pulmonary embolism) when the thrombus comes loose. This is potentially life-threatening. The affected vessel and surrounding tissue can also be damaged.

An important immediate measure in acute treatment is to elevate the affected leg and apply a compression bandage. This prevents further swelling and blood congestion. In any case, a doctor should be consulted.

Here one receives medication to dissolve the thrombus, which is supplemented by anticoagulant medication. The dosage of these drugs must be controlled frequently. In severe thromboses and young patients, the blood clot is often removed by surgery.

Risk factors for thrombosis are obstacles to the flow of blood, a slow flow rate and an increased tendency to clot. This is often caused by frequent alcohol consumption, frequent smoking, lack of exercise, obesity but also a lack of fluids. You can find detailed information on this topic at Thrombosis in the leg

Pulling or pulsating pain
Severe swelling of the leg including the foot
Feeling of heaviness and tension
Redness
Excessive heating
Sometimes fever and an accelerated pulse.

Pain in the lower leg is a common complaint.

The causes of this pain can be very diverse. They may be vascular or interstitial, bony, muscular or tendonous or a combination of these, although the causes can also be very different. As in other parts of the body, different types of pain can be differentiated on the lower leg.

For example, a dull pulsation usually indicates vascular causes (affects vessels), while a stabbing pain usually involves muscular problems. Pain due to bony causes is usually due to a fracture after a trauma, whereas pain of a vascular nature can occur due to thrombosis. Likewise, the vessels are the origin of edema, which causes problems especially in the lower leg, since they can develop a particularly high pressure here due to rigid connective tissue muscle fasciae.

Untreated, this usually leads to irreversible damage to the nerves and muscles. Furthermore, less serious causes can already be the origin of pain.If the legs are already strained too much during sports, some people will experience cramps immediately, others later. These cramps are not dangerous, but can be very painful.

You can read more detailed information on this topic here: Pain in the lower legA lower leg fracture is the fracture of one or both bones of the lower leg. Since these bones are very solidly built, a fracture occurs only after a massive application of force, such as after a traffic accident or a fall from great heights or a skiing accident. Signs of a fracture are severe pain and a lack of resilience of the affected leg.

Afterwards one should definitely go to a hospital or to a doctor. The prognosis for complete healing of a lower leg fracture is relatively high. If there is an open fracture, i.e. the bone is exposed to air, surgery must be performed immediately.

In the case of closed fractures, the type of therapy may vary. The bones can be stabilized with an intramedullary nail, plate and screws or an external fixator. After about 18 months, these objects are surgically removed.

In some cases, however, it is sufficient to immobilize the leg and let the bone heal on its own. For this purpose, a plaster cast is applied for a few weeks. As a rule, all fractures of the lower leg are resilient again after twelve weeks at the latest.

Complications that can occur after a fracture are thromboses, nerve and vessel damage and also wound healing disorders. The coordination of walking is also usually limited, which is why walking training is recommended. Lower leg edemas are often simply perceived as thick legs.

This leads to water retention in the tissue. They can be recognized by pressing a finger on the skin. If a dent remains after the pressure is released, this is considered to be edema.

They usually start at the ankles and rise from there towards the trunk. The causes of lower leg edema can vary widely and range from heart failure to kidney failure, thrombosis and local inflammation. This is also the reason why the underlying disease can often only be detected and treated at a late stage.

In the case of unilateral leg edema, there is usually a local outflow disorder. This is typically due to deep leg vein thrombosis, lymphedema or oedematous inflammation. If both sides are equally affected, the cause is usually an organ located further away.

The most common cause is heart failure. Kidney failure can also be the cause, as the amount of fluid in the body is too high. The therapy is cause-related, i.e. the diseases that are the cause of the edema are treated.

This can vary greatly depending on the cause or organ, and therefore has varying chances of recovery. Our next article may also be of interest to you: Edema in the legA lower leg ulcer is a common disease in diabetes mellitus, peripheral arterial occlusive disease (paVK) and chronic venous insufficiency following thrombosis. Infections, superficial skin lesions and tumors can also be causative.

In these cases, an undersupply of oxygen causes the skin to die off and to become defective, resulting in a deep, weeping wound. This can be accompanied by typical signs of inflammation such as redness, swelling or pain. The danger with such an ulcer is the colonization with bacteria.

This all leads to a slow healing process and it can take several months until the wound is completely healed. In severe cases, the healing process may even take years or the ulcer may remain permanently. The treatment can be either surgical or conservative.

Surgical measures are aimed at improving the underlying cause, i.e. increasing the blood circulation. Conservative measures can vary depending on the cause. However, they all include cleaning the wound, removal of developing coatings and prevention of drying out.

In the case of arterial causes, an attempt is made to increase the blood flow, while in the case of venous causes an attempt is made to prevent blood congestion by compression. The muscles of the lower leg are divided into several so-called boxes by connective tissue muscle skins. In each box there are several muscles.A high stiffness is an important characteristic of the muscle skins, as it is the cause of a so-called compartment syndrome.

A compartment syndrome is characterized by severe pain, numbness in the lower leg and foot and a feeling of tension. In addition, mobility is greatly reduced and the pulse on the foot is no longer palpable. This is caused by a dream like a blow to the muscle or a fracture of the bones, which results in bleeding into one or more muscle boxes.

This leads to an increase in pressure in the box, which reduces blood circulation, tissue dies and irreparable nerve damage occurs. Initially, compartment syndrome is treated by cooling and immobilization. Afterwards a surgical splitting of the muscle skin should be performed as soon as possible.

This usually relieves the affected compartment. After some time, the suture can be closed. Detailed information on this topic can be found in the next article: Compartment syndrome of the lower leg