The glossary.

The most common diseases and terms of the musculoskeletal system explained simply.

Medical gibberish often leaves perplexity. We therefore explain the most common diseases of the musculoskeletal system in a simple way. In addition to an explanation, find information about causes, symptoms, and treatment options.



Arthritis describes an inflammatory joint disease that can lead to damage to the joint surfaces. It must be distinguished from osteoarthritis, a degenerative joint disease that can be accompanied by wear and tear of the articular cartilage. If the joint inflammation occurs suddenly, it is referred to as acute arthritis. If this develops insidiously and makes itself felt again and again, it is referred to as chronic arthritis.

Arthrose Knie.

Osteoarthritis in the knee is also called gonarthrosis.



Coxarthrosis is an osteoarthritis of the hip joint and one of the most common forms of joint wear. Many people, especially at an advanced age, have wear and tear on the joints and the structures surrounding the joints. However, this wear and tear does not necessarily have to lead to complaints. On the contrary, the majority of people with joint wear and tear remain largely symptom-free and are hardly or not at all restricted in everyday life. Joint wear and tear without pain is therefore more common than joint wear and tear with pain. Symptoms occur when the joint reacts with irritation, inflammation and swelling due to overload or when the joints are severely affected.



Gonarthrosis is a degenerative disease characterized by the wear and tear of the cartilage layer of the knee joint. A distinction is made between 2 different types: medial gonarthrosis affects the inner part of the knee joint and lateral gonarthrosis affects the outer part. In most cases, it is a so-called "primary osteoarthritis", which is caused by age-related cartilage degradation. In the case of congenital deformities, certain diseases or injuries that cause wear and tear of the cartilage mass, this is referred to as "secondary gonarthrosis".



The abdomen bulges forward, the shoulder blade backwards, the doctor and also the therapist recognize it at first glance. Both a hollow back (hyperlordosis) and a hunchback (hyperkyphosis) are perfectly normal variations of the spine.


Hyperkyphosis is also colloquially understood to mean a hunched back.


Hyperlordosis is also known colloquially as a hollow back.

Hunched back.

You can find information on the subject of hunchbacks in the glossary entry "Hollow back".



Impingement syndrome, also known as bottleneck syndrome, describes an entrapment of tendons or joint capsule parts within a joint space, usually associated with pain. This often leads to a degenerative change in the joint, which is accompanied by limited mobility. Impingement syndrome usually manifests itself in the shoulder and hip joints, and more rarely in the ankle joint. This affects about 10% of the German population.


Sciatica is an irritation of the sciatic nerve. The sciatic nerve, also known as the sciatic nerve, is the longest and, with a diameter of 1.5 cm, also the thickest nerve in humans. It is composed of the spinal cord nerves of several vertebral segments from the 4th lumbar vertebra to the 3rd sacral vertebra. The sciatic nerve is the only nerve that supplies the lower leg.



Osteoarthritis of the knee is also known as gonarthrosis.


Labrum lesion.

A labrum lesion is a tear of the joint lip in the hip. Normally, this protrusion of fibrous tissue lines the acetabulum and thus acts as a damper. At the same time, the smooth surface allows the femoral head to slide into the acetabulum. In the case of the labrum lesion, only superficial cracks usually form at first, which enlarge with repetitive stress. As a result, the labrum can detach more and more from the edge of the acetabulum, exposing the cartilage in the acetabulum. This can then lead to hip osteoarthritis.


Lumbago or lumbalgia is also colloquially referred to as lumbago. One shot, then it's over: If the witch catches you, you can neither bend forward nor stand up for days because of the pain. Many people believe this, but fortunately it does not correspond to the facts at all. Lumbago, in technical jargon lumbalgia, lumbago or lumbar syndrome, is often a tension of the muscles. This may have been brewing for days and does not have to have anything to do with the movement that allegedly triggered the painful lumbago. On the contrary, you have probably even moved too little in the last few days or strained too one-sidedly.


Lumbalgia or lumbago is also colloquially referred to as lumbago.


Non-specific back pain.

Most of the time, it just hurts. In 80 percent of cases, the doctor makes the diagnosis of "non-specific back pain". This diagnosis does not mean that there is no cause for the back pain. Rather, medical diagnostics do not allow for a clear cause, as a variety of factors often influence back pain. Because factors such as unfavourable workload, lack of exercise, emotional stress, eating habits, overwork and other aspects play a role in non-specific back pain, experts also speak of so-called "bio-psycho-social" causes of pain.



Osteoarthritis is one of the most widespread diseases – and unfortunately it is not a question of age. Obesity, too little or no exercise, unfavourable eating habits as well as prolonged incorrect or excessive strain: all this can lead to osteoarthritis in joints. If pain occurs in joints such as knees or hips, the thought of osteoarthritis is often obvious – and of surgery on the affected joint.


Osteochondrosis is often observed in the area of the back, especially in symptom-free persons by incidental findings. Medical Greek refers to the flattening of the intervertebral discs, whereby the bones ("osteo"), the vertebral body and the cartilage ("chondro") of the intervertebral discs adapt. This adaptation is reflected in an increase in the joint surfaces due to the stress. In addition, the intervertebral discs change their elasticity and shape.


Bone loss, which doctors call osteoporosis, is an imbalance in the activity of osteoblasts, which build bone, and osteoclasts, which are responsible for breaking down bone tissue. As a result of this process of building up and degrading, our skeleton usually renews itself every 7 years and constantly adapts to new requirements. If osteoclast activity is predominant, the bone becomes porous over time, so that it is no longer able to cope with its task even at lower loads than usual.

Osteoarthritis of the hip joint.

Osteoarthritis of the hip joint is also known as coxarthrosis.

Osteoarthritis of the hip.

Osteoarthritis in the hip joint is also known as coxarthrosis.



Patellar tendinitis is a painful, chronic and degenerative disease of the bone-tendon junction in the area of the kneecap (patella). Patellar tendinitis is often the result of chronic overloading of the patellar tendon due to forced knee joint extension, as in jump-intensive and abrupt changes of direction (volleyball, handball, basketball, football). In addition, there are internal influences such as reduced elasticity, congenital ligament weakness or even kneecap protrusion.



Muscle soreness usually occurs after unusual, intense physical exertion. This leads to microscopic muscle fiber tears, which are accompanied by bleeding and inflammatory reactions, which trigger the pain of muscle soreness. The onset of pain is delayed after about 12 to 72 hours and can last up to a week. Muscle soreness is usually accompanied by no significant permanent damage and results in a regeneration of the muscle structures, which triggers adaptation reactions.


Spondylolisthesis is colloquially referred to as "spondylolisthesis". An often overrated myth in musculoskeletal complaints is the so-called spondylolisthesis. In this spondylolisthesis, a vertebral body slides forward (anterolisthesis) or backward (retrolisthesis).

Spinal disc herniation.

Herniated disc is probably the most overrated musculoskeletal disease. Intervertebral discs are also the buffers of the spine and prevent the vertebral bones from rubbing directly against each other during movement and stress such as walking, running, and jumping. In most cases, however, they can perform this task well despite a herniated disc.