Sacrum sacrovertebral angle, an angle of 30 degrees from the horizontal plane that provides a useful marker for a sling implant procedure. The pelvic surface of the sacrum is concave from the top, and curved slightly from side to side. Its middle part is crossed by four transverse ridges, which correspond to the original planes of separation between the five sacral vertebrae. The body of the first segment is large and has the form of a lumbar vertebra; the bodies of the next bones get progressively smaller, are flattened from the back, and curved to shape themselves to the sacrum, being
Canticum Sacrum Canticum Sacrum Canticum Sacrum ad Honorem Sancti Marci Nominis is a 17-minute choral-orchestral piece composed in 1955 by Igor Stravinsky (1882–1971) in tribute "To the City of Venice, in praise of its Patron Saint, the Blessed Mark, Apostle." The piece is compact and stylistically varied, ranging from established neoclassical modes to experimental new techniques. The second movement, "Surge, Aquilo", represents Stravinsky's first movement based entirely on a tone row. Though most often abbreviated ""Canticum Sacrum"", the piece's full name is "Canticum Sacrum ad honorem Sancti Marci Nominis", or "Canticle to Honor the Name of Saint Mark". Stravinsky selected all of