Inferior rectus muscle

Motility testing (evaluates diplopia on up-gaze/possible forced duction on inferior rectus muscle) lid position/assessment (rules out upper lid retraction) Bell s phenomenon (intact/absent)... 

Figure 32-6 (A) Note the asymmetry of visible sclera above each lower eyelid (arrows). By prism measurement this patient has an 8D left hypotropia in primary gaze. (B) Restriction of the left inferior rectus muscle on gazing up and left.

Fig. 12.7a-c. Endocrine orbitopathy (EO) is among the most common causes for proptosis. Axial (a), coronal (b) and sagittal (c) MDCT images of the orbit demonstrate severe bilateral thickening of intra-orbital muscles, which is usually most pronounced in the medial and inferior rectus muscles (arrows), leaves out the tendons, and may result in optic nerve compression at the aperture of the optical nerve canal (curved arrows). Hypertrophy of intra-orbital fat tissue is another feature typical of EO... 

It has also been argued that the conal muscles, i.e., the superior, inferior, medial, and lateral rectus muscles of the orbit, along with their tendons and cormective tissue layers, represent a space of their own (the conal space) and that this space may be affected by disease in its own right (Aviv and Miszkiel 2005). However, this view is not shared by all authors. 

In the pelvis, avulsion occurs primarily at six sites, which not surprisingly are the sites of the major muscle attachments. The three commonest sites are the anterior superior iliac spine (ASIS) (the origin of sartorius), the anterior inferior iliac spine (AIIS) (the rectus femoris origin) and the ischial tuberosity (the origin of the hamstring group). With these fractures acutely there is a clinical history of severe exertion, followed by pain and reduced function (Wootton et al. 1990) (Fig. 12.23). 

Fig. 12.24. Sites of pelvic avulsion injuries. A, iliac crest (abdominal muscle insertion). B, anterior superior iliac spine (sartorious muscle origin). C, anterior inferior iliac spine (rectus femoris origin). D, greater trochanter (gluteal insertions). Ey Lesser trochanter (illiopsoas). F, ischial tuberosity (hamstring muscle). G, body of pubis and inferior pubic ramus (adductors and gracillis)...

The muscles involved in this technique include the bilateral suboccipital muscles the rectus capitis posterior major, rectus capitis posterior minor, obliquus capitis inferior, and obliquus capitis superior. 

From lateral to medial, the deep layer of anterior muscles includes the rectus femoris, the iliopsoas and the pectineus (Fig. 12.2). The rectus femoris muscle has three separate proximal tendons direct (straight), indirect and reflected. The direct tendon originates from the anterior inferior iliac spine and continues down into a superficial aponeurosis which covers the anterior aspect of the proximal muscle (superficial aponeurosis) the indirect tendon arises from the superior acetabular ridge and forms a sagittal-oriented band (central aponeurosis) that is located inside the proximal muscle belly the thin reflected tendon is directed more medially to merge... 

Fig. 12.2. Anatomy of the anterior muscles and tendons of the hip. Schematic drawing of an anterior view through the hip illustrates the relationships of the anterior muscles to each other. The superficial tensor fasciae latae (Tfl) and sartorius (Sfl) arise from the anterior superior iliac spine (straight arrow). On a deeper plane, the rectus femoris (Rf) originates from the anterior inferior iliac spine (arrowhead). Observe the iliacus and the psoas muscles which join distally to insert through a common tendon onto the lesser trochanter (curved arrow). Medially to the iliopsoas tendon, the pectineus muscle (Pe) can be seen arising from the anterior aspect of the superior ramus of the pubis (Pb)...

Overuse tendinopathies of the hip affect mostly the tendon of the tensor fasciae latae (Bass and Connel 2002) and the rectus femoris tendon. Patients complain of localized anterior hip pain vdiich comes on after or, in more severe disease, during sport activities. This condition typically involves sprinters and is secondary to a forceful extension of the hip. Physical examination reveals tenderness over the anterior superior and anterior inferior iliac spines. Contraction of the muscle against resistance can increase the local pain. Clinically, the diagnosis of tensor fasciae... 

Fig. 12.29a-c. Rectus femoris tendon tear, a Long- and b short-axis 12-5 MHz US images obtained over the insertion of the proximal tendon of the rectus femoris on the anterior inferior iliac spine (AIIS) reveals a complete tear of the direct rectus femoris tendon (arrowhead) which appears retracted downward. A hypoechoic collection reflecting the hematoma (asterisk) is seen between the retracted tendon and the iliac spine. Superficial to the ruptured tendon, the iliacus and the sartorius (Sa) muscles can be appreciated, c Corresponding long-axis 12-5 MHz US image on the contralateral side demonstrates the intact rectus femoris tendon (arrows) which inserts into the anterior inferior iliac spine... 

Fig. 13.2a-c Normal quadriceps muscle, a-c Schematic drawings of a coronal view through the anterior thigh showing the muscle bellies forming the quadriceps from deep (a) to superficial (c). a,b The vastus intermedius (VI) is the deepest muscle. On each side, it is partially covered by the vastus lateralis (VX) and the more distal vastus medialis (VM). c The rectus femoris (RF) is located more superficially. It arises from a direct (DT) and an indirect (IT) tendon from the anterior inferior iliac spine and inserts into a long flat tendon (asterisk) that forms the superficial layer of the quadriceps tendon... 

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