Infraspinous Fossa

Fig. 6.40a,b. Normal infraspinatus and teres minor muscles, a Sagittal 12-5 MHz US image over the infraspinous fossa demonstrates the upper infraspinatus (InfraS) and the lower teres minor (Tm), each of which is characterized by an individual hyperechoic aponeurosis (arrows), b Same scanning plane in another patient. A single posterior muscle (arrowheads) formed by the union of the two bellies of the infraspinatus and teres minor is found. Observe the wide central aponeurosis of this muscle (arrows). Asterisk, spine of the scapula. The insert at the upper left side of the figure indicates transducer positioning... 

Insert needle electrode into infraspinous fossa two fingerbreadths... 

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