Coracoid Fractures

Fractures of the coracoid process are uncommon injuries that can be caused by direct trauma or avulsion. Avulsion fractures can be at the attachment of the coracoclavicular ligaments in the setting of acromioclavicular dislocation or at the muscular attachments in the setting of violent contraction. They can also occur in association with clavicular fractures and shoulder dislocation and can impede reduction in the latter.

Complications of coracoid fractures include hemorrhage into the muscles of the rotator cuff and damage to the suprascapular nerve.

Coracoid fractures have been classified into 5 types based on the location of the fracture plane:

• Type 1: Involve the tip (epiphyseal fracture)
• Type 2: Through the midportion.
• Type 3: Through the base (basal fracture). Most common.
• Type 4: Extend to the superior body of the scapula.
• Type 5: Extend into the glenoid fossa.

Each can be further subdivided into A and B classifications based on the absence or presence of damage to the clavicle or its ligamentous connections to the scapula.

Management is usually conservative for types 1-3. Internal fixation is often recommended for types 4 and 5.

A simpler classification divides them into two types based on the relationship of the fracture to the coracoclavicular ligaments: Type-I fractures are proximal to this attachment and can disrupt the scapuloclavicular connection. Type-II fractures are distal to the coracoclavicular ligaments. Type I fractures often require internal fixation, while type II fractures can be managed conservatively.

The image above shows a type 2 fracture. The anteroposterior view reveals a double contour of the coracoid process (pink arrow), suggestive of displacement and early callus formation. The axillary view shows the fracture plane (white arrows) through the midportion of the coracoid process.

References

• Eyres KS, Brooks A, Stanley D. Fractures of the coracoid process. J Bone Joint Surg Br. 1995 May;77(3):425-8.
• Ogawa K, Yoshida A, Takahashi M, Ui M. Fractures of the coracoid process. J Bone Joint Surg Br. 1997 Jan;79(1):17-9.