• characterized by a net demineralization of bones
• results from a disruption of the normal balance of calcium deposition and resorption
• vertebral body osteoporosis occurs in all vertebrae but most commonly in thoracic
• especially common in postmenopausal women

• humpback
• increase in thoracic curvature (posteriorly)
• can result from erosion of the anterior part of one or more vertebrae
• occurs in geriatric people of both sexes
• in women sometimes referred to as Dowager's hump

• characterized by anterior rotation of the pelvis
• increase in lumbar curvature (more convex anteriorly)
• abnormal extension deformity may be associated with weakened trunk musculature

• abnormal lateral curvature accompanied by rotation of the vertebrae
• most common back deformity in girls 12-15
• causes of Scoliosis:
• myopathic scoliosis- asymmetric weakness of the intrinsic back muscles
• hemivertebra- failure of half the vertebrae to develop
• difference of length in lower limbs

surgical excision of one or more spinous processes and the supporting laminae in a particular region of the vertebra column

commonly denotes the removal of the vertebral arch by transecting of the pedicles

• usually result from sudden forceful flexion
• injury is typically a crush or compression fracture
• possible to dislocate and fracture the articular facets b/w 2 vert and rupture the interspinous ligaments

• most common congenital anomoly of the vert column
• laminae of L5 and/or S1 fail to develop normally and fuse
• present in up to 24% of people
• location often indicated by a tuft of hair

• one or more vertebral arches may almost completely fail to develop
• associated with the herniation of the meninges and/or spinal cord(meningomyelocele- can have neurological symptoms in severe cases)

Dislocation of Vertebrae

Cervical Vertebrae

• slight dislocation can occur w/o damage to the spinal cord
• facet jumping- locking of the displaced articular processes- doesn't occur a radiograph my not indicate cord damage because the bodies can slip back into place
• MRI may reveal the damage

Whiplash

the anterior longitudinal ligament is severly stretched and may be torn

Dislocation of Vertebrae

Thoracic and Lumbar

is uncommon because of interlocking articular processes

T11 and T12 most commonly fractured noncervical vertebrae

Fractures of the interarticular parts of the vertebral laminae of L5 may result in spondylolisthesis

Susceptibility results from a failure of the centrum of L5 to unite adequately with the neural arches during development

Forward displacement of the L5 vertebral body relative to the sacrum

may result in pressure on the spinal nerves of the caudia equina causing back and lower limb pain

reduces the anteroposterior diameter of the pelvic inlet

• describes a stenotic (narrow) vertebral foramen in one or more lumbar vertebrae
• may cause compression of one or more spinal nerve roots
• surgical treatment: decompressive laminectomy

*note: lumbar spinal nerves inc in size as the vertebral column descends, but the IV foramina decrease

dec in bone density and strength-> superior and inferior surfaces of vert become concave-> IV discs lose turgor

IV disc inc in size with inc in age->more convex and diameter inc

Result of both interactions is osteophytes(bony spurs) around the margins of the vert. bodies

• a procedure that may be used for treatment of back pain caused by the disease of Zygapophysial joints
• nerves are destroyed by radiofrequency
• directed at the articular branches of 2 adjacent posterior rami of the spinal nerves

• dens is set free-> atlanto-axial subluxation-incomplete dislocation of the median atlanto-axial joint
• complete dislocation can lead to quadriplegia or death

• weaker then the transverse ligament of the atlas
• results in an increase of approximately 30% in the range of movement to the opposite side

Back Pain

Five Categories of structures recieve innervation in the back and can be sources of pain:

1.Fibroskeletal Structures- periosteum, ligaments, and anuli fibrosi of IV discs

2. Meninges- coverings of the spinal cord

3. Synovial Joints- capsules of the zygapophysial joints

4. muscles- intrinsic muscles of the back

5. nervous tissue- spinal nerves or nerve roots exiting the IV foramina-typically referred pain

* 1st 2 are innervated by meningeal branches

*next 2 by posterior rami

• used to obtain a sample of CSF from the cistern
• needle inserted into the subarachnoid space between L3 and L4
• at these levels in adults reduced danger of damaging the spinal cord

lose sensation inferior to the level of the block

agent inserted into:1) extradural space in the sacral canal through the sacral hiatus 2) through posterior sacral foramina

an injury in which only ligamentous tissue or the attachment of ligament to bone is involved without dislocation or fracture

results from excessively strong contractions