CT Anatomy Tutorials:
The Hamstring muscles

 

 

Arrows

Red=semitendinosus

Gold=combined hamstring tendons

Yellow=semimembranosus

Green=biceps femoris - long head

Magenta - semimembranosus and biceps femoris - long head

Text

GM=Gluteus Maximus

 

 

           

Axial CT sections from the ischial tuberosity to the level of the perineum

The tendons for the semitendinosus, the semimembranosus, and the long head of the biceps femoris have a common origin at the ischial tuberosity as shown in the first image to the left. While it is stated that the semitendinosus and the long head of the biceps have a conjoint tendon of origin, this conjoint tendon cannot be resolved on CT separately from the tendon of the semimembranosus. The first visible separation is shown in the second image where the tendons for the semimembranosus and the long head of the biceps femoris are seen as a single structure. Note that at this level, the semitendinosus is seen as a muscle belly which progressively enlarges over the next two image while the other muscles remain tendinous. In the third image, the tendons of the semimembranosus and the long head of the biceps femoris can be seen separately. Note also the positions of these structures in the third and fourth images. The tendon for the semimembranosus lies anterior (deep) to the muscle belly of the semitendinosus while the tendon for the long head of the biceps lies laterally. At the four levels shown, all the hamstring muscles and tendons lie deep to the gluteus maximus muscle.

Arrows

Red=semitendinosus

Yellow=semimembranosus

Green=biceps femoris - long head

Purple=tendon of biceps femoris - short head

Text

GM=Gluteus Maximus

AM=Adductor Magnus

 

 

           

Axial CT sections from the upper third of the thigh below the perineum

These four images which are at progressively more inferior levels show several changes. The semitendinosus increases slightly in size, and at lower levels lies between the muscle bellies of the semimembranosus medially and the long head of the biceps laterally. The semimembranosus remains tendinous and lies deep to the muscle belly of the semitendinosus in the first three images. On the most inferior image, the muscle belly starts to develop medial to the semitendinosus. The belly of the long head of the biceps enlarges rapidly below the gluteus maximus and becomes larger than the other two muscles. Note the appearance of the tendon for the short head of the biceps femoris muscle.

<---OVERVIEW
<---HOME PAGE

  NEXT--->