Overview - Clavicle

Ligaments

Acromioclavicular ligament

Coracoacromial ligament

Coracoclavicular ligament(Trapezoid, Comoid)

 

The clavicle is not a straight bone.

Classification

The most popular is dividing the clavicle into thirds.

  • Medial third
  • Middle third
  • Lateral third

The significance of this is that:

  • Medial third injuries are rare.

  • Most middle third injuries will heal with non operative intervention.

  • Some lateral third injuries may go on to non union.

Allman (1967)

  • Group I - Midshaft fractures
  • Group II - Lateral end fractures (see lateral clavicle for further subclassification)
  • Group III - Medial end

Edinburgh classification (1998)

 

Robinson et al added this classification looking at the probability of a clavicle fracture going on to a non union.

They divide the clavicle into three regions  i.e., the diaphysis and the two ends

  • Type 1 - The medial 1/5, ie area of clavicle lying medial to a vertical line drawn upward from the centre of the first rib

  • Type 2 - Middle 3/5ths

  • Type 3 - Lateral 1/5th of the clavicle, ie. lateral to a vertical line drawn upward from the centre of the base of the coracoid process, a point normally marked by the conoid tuberosity.

Type 1

Medial 1/5

Area of clavicle lying medial to a vertical line drawn upward from the centre of the first rib.

Type 2

 Middle 3/5ths

Type 3

Lateral 1/5th

Lateral to a vertical line drawn upward from the centre of the base of the coracoid process, a point normally marked by the conoid tuberosity.

A - No displacement

B- Displacement >100%

A - No displacement

B- Displacement >100%

A - No displacement

B- Displacement >100%

1A1 - Extraarticular

1A2- Intraarticular

1B1- Extraarticular

1B2- Intraarticular

2A1 - No angulation

2A2 - Angulated

2B1 - Simple or wedge comminuted

2B2 - Isolated or comminuted segmental

3A1 - Extraarticular

3A2 - Intraarticular

3B1 - Extraarticular

3B2- Intraarticular

 

See prognostic index calculators


References

 

C. Michael Robinson, Charles M. Court-Brown, Margaret M. McQueen, and Alison E. Wakefield; Estimating the Risk of Nonunion Following Nonoperative Treatment of a Clavicular Fracture; JBJS - A 2004 86: 1359-1365

 

C.M. Robinson, Fractures of the clavicle in the adult. Epidemiology and classification. JBJS - B 1998 80: 476484


Last updated 11/09/2015