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.

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: 476–484

Last updated 11/09/2015