MRI

Epidemiology

Rare

- unilateral

- bilateral

Mechanism

Compression

Lateral Compression

Rotation

Clinical

Skull base pain

Cock Robin

Cranial nerve injury

Classification Anderson & Montesano

Type I

Impaction of a condyle 

Definition

Facet joint dislocations secondary flexion distraction injury

Epidemiology

10%

Stages

1. Unifacet subluxation - interspinous process widening

2. Unifacet dislocation - 25% anterolisthesis

3. Bifacet dislocation - 50% anterolisthesis

4. Complete vertebral translation - 100% anterolisthesis

Unilateral Facet Joint Dislocation

Definition

Burst fractures

- injury to anterior and middle columns +/- posterior column

Mechanism

Vertical compression

Epidemiology

10% cervical fractures

Most commonly C5/6

Pathology

Anterior & middle columns fail

- if severe, posterior ligament complex fails

Definition

Minimal trauma fracture

- secondary to osteoporosis

- wedge fractures

Epidemiology

F > M

More common in elderly patients

Uncommon in men < 75

- look for alternative diagnosis

DDx

Renal failure

Malignancy - metastasis

Infection

Clinically

Can present with pain

Definition

Groin pain in athletes

- secondary to tear in external oblique fascia

Epidemiology

Sports with aggressive adduction

- hockey / soccer

Pathology

Tears in external oblique fascia

- tend to be central

- around spermatic cord and ilioinguinal nerve

- pain may be from nerve entrapment

DDx

Adductor Longus Tear

Aetiology

Throwing injury

- seen in the throwing athlete

- repetitive microtrauma / valgus stress

- develop laxity

History

Initially

- lose velocity / accuracy

Develop medial pain

40% ulna nerve symptoms

Epidemiology

Usually occurs in patients over 60

- due to decreased vascularity & collagen weakness

Younger patient on steroids / growth hormone

Occasionally occurs in young athlete with excessive contracture

Aetiology

Often preceded by quadriceps tendinosis

Anatomy / Biochemistry

Constituents of cartilage

Epidemiology

Adolescent apophyseal avulsion

- treat non operatively

- unless displaced > 2 cm

Adult

- soft tissue avulsion

Aetiology

Usually associated with sporting activities

- skiing

- water skiing

Violent contraction

- knee extended

- hip flexing

Anatomy

Definition

Multi-ligament knee injury (MLKI)

- 2 or more ligaments disrupted

Knee dislocation

- ACL + PCL + one of collaterals 

Mechanism of injury

High energy (MVA)

Low energy (sport)

- low energy has 5% arterial injury