SEMI-MEMBRANOUS MUSCLE (M. SEMIMEMBRANOSUS)

definition

The semi-membranous muscle lies on the back of the thigh and belongs to the "hamstring muscles" located there. It extends roughly from the lower edge of the pelvis to just below the inside of the knee joint, where it attaches to the upper inner shin. When the muscle contracts, it bends in the knee joint. But it can also have a supportive effect when stretching the leg in the hip, for example when the thigh is bent.
The semi-membranous muscle bears its extraordinary name due to its long, broad tendon of origin. Only well below its origin in the pelvis does the muscle develop a strong muscle belly, before that the muscle with its thin, broad course is reminiscent of a "membrane".
The attachment tendon of the muscle on the shinbone represents an anatomically famous structure: The appearance of the broadly diversified attachment on the upper inner shinbone is reminiscent of a goose foot, which is why this structure was also named anatomically, namely as the deep-set goose foot ("Pes anserinus profundus"). On the surface of this, tendons from three other muscles form the superficial goosefoot.

function

Because of its course, the muscle supports movement in both the hip joint and the knee joint. in the hip joint does he have the function of a Streckers (Extensor) and Adductor. An extension of the hip joint occurs, for example, when extending the bent thigh but also when standing upright. Adduction is the Latin word for Bring upThe semi-membranous muscle can bring the splayed leg back up to the body.
in the Knee joint the muscle supports the diffraction (Inflection) and the Inward rotation (Internal rotation). In other words, movements in which the lower leg is moved towards the thigh, such as when standing on one leg, or the lower leg is turned inward.

common illnesses

The hemi-tendon muscle can be damaged from damage to the Sciatic nerve ("Sciatic nerve") may be affected. The nerve supplying it (N. tibialis) arises from the sciatic nerve. If there is serious damage, the entire ischiocrual musculature on the back of the thigh can fail. Thus, the front thigh muscles of the opponent are missing and painful hyperextension of the knee joint can occur Quadriceps femoris muscle come.
In addition, athletes can experience typical muscle injuries such as overstrain strain, Torn hamstring or more complete Muscle tear come. (Tendon) irritations can also occur.
The muscle is not a disease but has an important clinical role in the treatment of a disease front Torn cruciate ligament. In so-called "cruciate ligament surgery", the most frequently performed cruciate ligament surgery, the tendon of the Hemi-tendon muscle completely removed. It is then "folded" several times and used as a stable replacement for the cruciate ligament in the knee. If the tendon of the hemi-tendon muscle is not strong enough or for some other reason not sufficient for a cruciate ligament surgery, the tendon of the hemi-diaphragm muscle can be removed and inserted as an alternative.

Strengthening and stretching

In principle, all exercises in which the Elongation of the leg stepped up and thus the (knee) flexor group on the back of the thigh is stretched. Classically, the athlete achieves this by trying to reach the toes with his fingertips with his legs straight and the back as straight as possible. This stretching exercise is often found to be very uncomfortable and should not be overdone!
The muscles can be strengthened, especially in the gym, using specially designed equipment. All exercises in which the knee joint is bent (if necessary with a counterweight) strengthen the semi-membranous muscle. (So-called "leg biceps curls")

Synergists:
In the hip joint:
Straightener: Gluteus greater and middle muscles (Mm. Glutei maximus et medius), Biceps thigh muscle (M. biceps femoris), Hamstring muscle (M. semitendinosus)
Adductors: Comb muscle (M. pectineus), short and long adductor (M. adductor brevis et longus), great adductor (M. adductor magnus), lean muscle (M. gracilis)

In the knee joint:
Flexor: Tailor's Muscle (M. sartorius), lean muscle (M. gracilis), Biceps thigh muscle (M. biceps femoris), Two-headed lower leg muscle (M. gastrocnemicus)

Antagonists:
In the hip joint:
Flexor: Iliac-lumbar muscle (M. iliopsoas), Tailor muscle (M. sartorius), Thigh tie tensioner (M. tensor fasciae latae), Four-headed hamstring muscle - straight part (M. rectus femoris)
Abductors: Thigh Tie Tensioner (M. tensor fasciae latae)glutes, small and medium muscles (M. gluteus minimus et medius)

In the knee joint:
Straightener: Four-headed hamstring muscle (M. quadriceps femoris)