Biceps Femoris Long Head

Sciatic Nerve (Tibial Portion), Anterior Division, Sacral Plexus, L5, 

Insert the electrode at the midpoint of a line between the fibula head (FH) and the ischial tuberosity (IT). 

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Biceps femoris — long head or short head ... 

In the posterior thigh, the most common muscle to tear is the biceps femoris (long head involved in approximately 85% of all cases of hamstring injuries), probably because this muscle contains a high proportion of type 2 fibers, plays an eccentric function and is intrinsically more inextensible due to its double origin from the femur and the ischial tuberosity (Garret 1990 Slavotineck et al. 2002). In a considerable number of cases (37%), the injury to the biceps femoris occurs in association with a semitendinosus strain, whereas the isolated rupture of the semitendinosus (30%) and semimem-... 

Fig. 12.8. Anatomy of the posterior (ischiocrural) muscles and tendons of the hip. Schematic drawing of a posterior view through the hip illustrates the insertion of the posterior muscles onto the ischial tuberosity (IT). The gluteus maximus (Gma) is shown in a semitransparent rendering over the ischiocrural muscles. Beneath it, observe the semimembranosus (sm), semi-tendinosus (st) and long head of the biceps femoris (Ihb) muscles. The semimembranosus has a separate tendon (I), whereas the semitendinosus and the long head of the biceps arise from the lateral aspect of the ischial tuberosity (IT) through a common tendon (2). Note the relationships between these muscles and the sciatic nerve (SN). GT, greater trochanter...

Fig. 13.34a-c Acute tear of the distal short head of the hiceps muscle in a soccer player, a Short-axis and b long-axis 12-5 MHz US images show a hypoechoic hematoma (arrow) located within the short head (SH) of the biceps femoris muscle. The overlying long head (LH) is normal, c Photograph of the posterior thigh reveals the ecchymotic skin (arrowhead) related to muscle rupture... 

Fig. 14.88a-c. Complete tear of the common peroneal nerve in a patient with previous knee dislocation, a Long-axis 12-5 MHz US image over the peroneal nerve in the popliteal fossa. The nerve has a wavy course and is characterized by abnormal thickened (arrowheads) and thinned (arrows) segments related to the interruption and laceration of the fascicles, b Transverse oblique 12-5 MHz US image over the lateral knee with c lateral radiographic correlation demonstrates abnormal hypoechoic tissue related to the avulsion of the biceps femoris tendon (arrows) from its insertion (open arrowhead) into the fibular head (FHj.Note the close relationship of the ruptured biceps with the torn nerve (white arrowheads). On the radiograph, a small fleck of bone (curved arrow) appears retracted proximally with the torn biceps tendon... 

If the electrode is inserted too medially it will be in the semimembranosus if inserted too laterally it will be in the long head of the biceps femoris. 

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