The Vertebral Column

1. The Vertebral Column

2. 33 vertebra in total • 7C • 12T • 5L • 5S (fuse by age 30) • 4 coccygeal (form coccyx) • ¼ of length = IV disc • Synovial zygapophysial joints = flexibility

3. Features of All Vertebrae • Vertebral body • Supports weight • Superior and inferior end plates (discs of hyaline cartilage) = epiphyseal rim • Centrum (POC) • Vertebral arch • Pedicles • Laminae • Vertebral foramen  vertebral canal • Vertebral notches  IV foramina • Seven processes • Spinous • Transverse (x2) • Articular (x4)

5. Cervical Vertebrae • Transverse process • Foramen transversarium / transverse foramin (C1 – C6 = vertebral artery) • Anterior and posterior tubercle • Body • Uncus (uncinate process) • Spinous processes – bifid (C3-C6) • C7 – vertebra prominens

6. Atlas – no body, no spinous process, pedicles = lateral masses (bear weight). • Ant / post arch • Ant / post tubercles • Fovea for the dens • Axis • Dens (odontoid process) • Superior articular facets • Transverse ligament of atlas

7. Thoracic Vertebrae • T1: costal facet for 1st rib, demifacet for 2nd rib • T2 – T8 = demifacets, vertical articular processes • Permit rotation, some lateral flexion • Spinous processes angle inferiorly and overlap • T9 – T11: Single costal facet • T12: One demifacet, most commonly fractured vertebra

9. Lumbar vertebrae • Supracristal line crosses L4/L5 IV disc • Facets in sagittal plane – permit flexion and extension • Also accessory and mammillary processes • Lumbosacral angle (normally 130-160)

10. Sacrum • Superior half transmits force L5 to ilia • Sacral canal (for caudaequina) • Sacral foramina (ventral and dorsal) • Base = superior surface of S1 • Sacral promonory • Apex = S5 • Articular facet for coccyx) • Pelvic surface = smooth • Lateral surface • Median / intermediate / lateral sacral crests • Sacral hiatus • Sacral cornua

11. Coccyx • Fuses with sacrum, though Co1 can remain separate (has coccygeal cornua, remnants of articular processes) • Provides attachment for glut max, coccygeus, anococcygeal ligaments • Apex is palpable 2.5cm posterosuperior to the anus

12. Ligaments of the Spine • Ligamentumflavum (connects laminae) • Supraspinous ligament • Interspinous ligament • Nuchal ligament (occiput-C1-C7) • Posterior longitudinal ligament (prevents herniation) • Anterior longitudinal ligament (limits extension)

13. Superficial Back Muscles

14. Erector spinae

15. Deep intrinsic back muscles • These interconnect and stabilise– found deep to spinalis • Semispinalis • Multifidus • Rotatores (brevis and longus) • Interspinales • Intertransversarii

18. Anatomy of the Pelvis

19. Bony Pelvis • 3 bones each side, forms pelvic girdles • Oscoxae = ilium, ischium, pubis • Ilium • Arcuate line • Iliac crest • Iliac fossa • Auricular surface • Iliac tuberosity • Ala • Gluteal lines • ASIS, AIIS, PSIS, PIIS

20. Ischium • Body • Ramus (obturator foramen) • Greater sciatic notch • Ischial spine • Lesser sciatic notch • Ischial tuberosity • Pubis • Superior ramus (acetabulum) • Inferior ramus • Body of pubis • Pubic crest • Pubic tubercle • Pubic symphysis • Pecten pubis

24. Muscles of the pelvis • Lateral wall = obturator internus (traverses lesser sciatic foramen to attach on greater trochanter), obturator fascia • Posterior wall = SI joint and piriformis (arises from sacrum, passes through greater sciatic f. to attach to greater trochanter) • Pelvic floor = pelvic diaphragm = coccygeus + levator ani

26. Levator ani • Broad sheet between pubic bodies and ischial spines. Supports abdominopelvic viscera and is tonically contracted to maintain continence • Puborectalis = puborectal sling • Pubococcygeous • Muscle slips names after structures: pubo-analis, puboperinealis, pubovaginalis, puboprostaticus • Iliococcygeus (most posterolateral part).

28. Peritoneum of Pelvis

29. Learn for Surg Rotation

30. Arteries of the pelvis