posterior approach

Recurrent Posterior Instability

Definition

 

Patients usually complain of subluxation rather than dislocation

- rarely requires reduction

 

Different entity to acute posterior dislocation usually

 

Epidemiology

 

Rare

 

Aetiology

 

1.  Ligamentous laxity > 50%

- commonly associated with MDI

- posterior only 20%

- posterior & inferior 20%

Thoraco Lumbar Fracture

Xray Assessment

 

A:  Alignment

B:  Bony

C:  Canal

D:  Disc

S:  Soft tissues

 

Goals of surgery

 

1.  Correct deformity

2.  Restore stability

3.  Decompress neural elements if required

 

MRI

 

Advantage

- defines level of conus

- may need anterior rather than posterior surgery if lesion above conus

Thoracic Disc Disease

Epidemiology

 

0.05% incidence

- rare due to stabilising effect of rib cage

- even more rare to have symptoms

 

Reasoning

1.  Discs are narrower

2.  Foramina larger

3.  Thoracic spine

- facet joints orientated for rotation

- lumbar spine for flexion extension

- flexion is typically the motion which ruptures annulus

 

Anatomy