| annulus tendineus communis | A fibrous ring that surrounds the optic canal and the medial part of the superior orbital fissure; it gives origin to the four rectus muscles of the eye and is partially fused with the sheath of the optic nerve. Synonym: annulus tendineus communis, Zinn's ligament, Zinn's ring, Zinn's tendon. (05 Mar 2000) |
|---|
| arcus tendineus | A white, fibrous band attached to bone and/or muscle, arching over and thus protecting neurovascular elements passing beneath it from injurious compression, a linear thickening of the deep fascia of a muscle which provides attachment for ligaments and/or muscle fibres. Synonym: arcus tendineus. (05 Mar 2000) |
|---|---|
| arcus tendineus fasciae pelvis | A linear thickening of the superior fascia of the pelvic diaphragm extending posteriorly from the body of the pubis alongside the bladder (and vagina in the female) and giving attachment to the supporting ligaments of the pelvic viscera. Synonym: arcus tendineus fasciae pelvis. (05 Mar 2000) |
| arcus tendineus musculi levatoris ani | <anatomy> A thickened portion of the obturator fascia that extends in an arching line from the pubis posteriorly to the ischial spine and gives origin to part of the levator ani muscle. Synonym: arcus tendineus musculi levatoris ani, arcus tendineus of obturator fascia. (05 Mar 2000) |
| arcus tendineus musculi solei | <anatomy> A tendinous arch stretching over the popliteal vessels between the tibia and fibula, that gives origin to the central portion of the soleus muscle. Synonym: arcus tendineus musculi solei. (05 Mar 2000) |
| arcus tendineus of obturator fascia | <anatomy> A thickened portion of the obturator fascia that extends in an arching line from the pubis posteriorly to the ischial spine and gives origin to part of the levator ani muscle. Synonym: arcus tendineus musculi levatoris ani, arcus tendineus of obturator fascia. (05 Mar 2000) |
| hiatus tendineus | The aperture in the aponeurotic insertion of the adductor magnus that transmits the femoral artery and vein from the adductor canal to the popliteal space. Synonym: hiatus tendineus, hiatus adductorius, femoral opening, tendinous opening. (05 Mar 2000) |
| annulus | Ring like structure, adj. Annulate. (18 Nov 1997) |
| annulus abdominalis | The opening in the transversalis fascia through which the ductus deferens (or round ligament in the female) and gonadal vessels enter the inguinal canal. Located midway between anterior superior iliac spine and pubic tubercle, it is bounded medially by the lateral umbilical ligament (inferior epigastric vessels) and inferiorly by the inguinal ligament. Indirect inguinal hernias exit the abdominal cavity via the deep inguinal ring Synonym: annulus inguinalis profundus, abdominal ring, annulus abdominalis, internal inguinal ring. (05 Mar 2000) |
| annulus ciliaris | <anatomy> Tissue that includes the group of muscles that act on the eye lens to produce accommodation and the arterial circle of the iris. The inner ciliary epithelium is continuous with the pigmented retinal epithelium, the outer ciliary epithelium secretes the aqueous humour. (18 Nov 1997) |
| annulus conjunctivae | A narrow ring at the junction of the periphery of the cornea with the conjunctiva. Synonym: annulus conjunctivae. (05 Mar 2000) |
| annulus femoralis | The superior opening of the femoral canal, bounded anteriorly by the inguinal ligament, posteriorly by the pectineus muscle, medially by the lacunar ligament, and laterally by the femoral vein. Passageway by which many lymphatics from lower limb pass to abdomen. Accommodates enlargement of femoral vein in Valsalva manoeuvre. Often occupied by a lymph node (Cloquet's) and is the site of femoral hernias. Synonym: annulus femoralis, crural ring. (05 Mar 2000) |
| annulus fibrocartilagineus membranae tympani | fibrocartilaginous ring of tympanic membrane |
| annulus fibrosus | One of four fibrous rings that surround atrioventricular and arterial orifices of the heart, providing attachment for the valve leaflets and maintaining patency of the orifice. As part of the fibrous skeleton of the heart, the fibrous rings also provide origin and insertion for the myocardium. Synonym: annulus fibrosus cordis, annulus fibrosus, coronary tendon, fibrous ring, Lower's ring. (05 Mar 2000) |
| annulus fibrosus cordis | One of four fibrous rings that surround atrioventricular and arterial orifices of the heart, providing attachment for the valve leaflets and maintaining patency of the orifice. As part of the fibrous skeleton of the heart, the fibrous rings also provide origin and insertion for the myocardium. Synonym: annulus fibrosus cordis, annulus fibrosus, coronary tendon, fibrous ring, Lower's ring. (05 Mar 2000) |
| annulus fibrosus disci intervertebralis | The ring of fibrocartilage and fibrous tissue forming the circumference of the intervertebral disc; surrounds the nucleus pulposus, which is prone to herniation when the annulus fibrosus is compromised. Synonym: annulus fibrosus disci intervertebralis, annulus fibrosus, fibrous ring of intervertebral disc, fibrous ring. (05 Mar 2000) |