100 Must-Know Gross Anatomy Concepts for Exam Prep

Lumbar Puncture

• The needle is usually inserted between the L3/L4 or L4/L5 vertebrae.

Anatomy

• The horizontal line through the upper points of the iliac crests corresponds to the L4 verterbra.
• The spinal cord typically ends at L1 in adults.

Pre-Procedural Examination

• The patient's neurological status and medication list should be examined before performing a lumbar puncture.

Increased Intracranial Pressure

• The cerebellar tonsils may herniate through the foramen magnum if there are signs of increased intracranial pressure.

Spinal Anatomy

• The dural sac extends caudally to S2.

Herniated Lumbar Discs

• The L5 nerve root is usually involved in a herniation at the L4/L5 level.

Spinal Deformities

• Kyphosis results in an exaggeration of the thoracic curvature and may occur in elderly persons due to osteoporosis or disk degeneration.
• Lordosis results in an exaggeration of the lumbar curvature and may occur temporarily during pregnancy, spondylolisthesis, or potbelly.
• Scoliosis is a complex lateral deviation or torsion of the spine that may be caused by poliomyelitis, leg length discrepancy, or hip disease.

Fractures

• Colles' fracture is the most common fracture of the forearm, occurring commonly after age 50, and results in a ventral angulation of the wrist when the distal fragment is anteriorly displaced.
• Scaphoid fracture occurs as a result of a fall onto the palm when the hand is abducted, and may not show on X-ray films for 2 to 3 weeks due to delayed presentation, but pain occurs primarily on the lateral side of the wrist.
• Boxer's fracture typically occurs in professional boxers, involving the necks of the metacarpal bones.

Nerve Injuries

• The radial nerve could be injured in a humerus fracture at the surgical neck.
• The radial nerve could be injured in a humerus fracture at midshaft.