Hamstring

The ischiocrural muscles, also ischiocrural muscles or hip extensor or rear thigh muscles called, are a group of muscles that are located on the back - caudal dorsal in humans, in animals - the thigh are. In animal anatomy, these muscles are also referred to as background cheek muscles or long seat leg muscles. In the Anglo-American literature this muscle group is called ischiocrural muscles or is summarized as hamstring.

The hamstrings muscles

• Biceps femoris ( " Two-Headed thigh muscle ", " hamstrings " )
• Semitendinosus ( " semitendinosus muscle " )
• Musculus semimembranosus ( " semimembranosus muscle " )

Function

The main functions of the back thigh muscles are the hip extension and knee flexion.

The hamstrings muscles but - especially in physical exercise such as running and cycling - to participate in movements involving the extension of the knee with it. So does in cycling after about 80 ° of the pedaling cycle ( measured from the top dead center, the highest pedal position ) of the biceps femoris, but probably also the Mm. semitendinosus and semimembranosus ( they were not included in many studies ) a large part of the power- efficient work by exerting pressure on the pedals.

Requirement for this " paradoxical " effect is a guide or fixation of the foot. " Paradox" the effect is called, because when the thigh muscles contributes to the development of force against gravity, usually the knee extension front thigh muscles, this takes.

The phenomenon was discovered in 1903 by the American physiologist Lombard and named after him as " Lombard'sches paradox". It has also been demonstrated for the sprint in athletics.

The ischiocrural muscle relieves propriorezeptiv in knee extension the anterior cruciate ligament ( anterior cruciate ligament ), as it moves, the plateau of the tibia (tibia ) from the condyle of the femoral bone ( femur) to the rear.

Clinical Significance

A tear or avulsion of part or the whole hamstrings muscles is a common injury that often occurs in sports with sudden, abrupt movements such as water skiing or football. The treatment can be performed surgically or conservatively, with the decision for one or the other way even after the extent of the injury depends ( complete tear or only a part ).

In veterinary medicine, the ischiocrural muscles is commonly used for intramuscular injection.