What is the diagnosis?

Coronoid Process Fracture 

Figure 2. Figure 1 with fracture in red, annotation by author. Image from Ortho EM Pearls Image Bank

• Pearl: Coronoid process fractures are commonly associated with elbow dislocations, occurring in up to 15% of elbow dislocations [1]. 

• Pearl: A coronoid process fracture is one portion of the “terrible triad” of elbow injuries, which also include elbow dislocation and radial head fracture [1]. Be sure to assess for these injuries in patients with coronoid process fractures. 

What is the mechanism of injury?

Typically caused by high energy mechanisms such as MVC or playing contact sports. Can also occur from a fall onto an outstretched hand, particularly with hyperextension of the elbow [1].

What physical exam findings are expected?

The primary physical exam findings will be swelling and diffuse tenderness of the elbow. 

If there is an associated dislocation of the elbow, there will typically be an obvious deformity. 

Always assess for signs of open fractures. 

• Pearl: Be sure to evaluate the stability of the elbow. This can be done with a valgus stress test and posterolateral drawer test [2]. 

Which imaging modalities can be used?

Plain radiograph is the initial imaging modality of choice. The lateral view is typically the best view to appreciate the fracture and classify the type of fracture [2].  

• Pearl: Coronoid fractures can be classified into Type 1, Type 2, or Type 3 fractures. Type 1 involves the tip of the coronoid process, Type 2 involves up to 50% of the coronoid process, and Type 3 involves >50% of the coronoid process [3]. 

What is the management in the ED?

Management consists of the identification of the injury, pain management, and brief immobilization [2]. It is important to perform a thorough physical exam to identify any associated injuries, neurovascular compromise, or signs of an open fracture. Prompt reduction of associated elbow discloation is indicated. Imaging should be obtained both pre and post reduction. Pearl: If there is concern for dislocation or intra-articular bony fragments exists, a CT scan can be helpful to assess the joint space

• Pearl: Prolonged immobilization can lead to joint stiffness, so ensure patients have prompt orthopedic follow up regardless of need for surgery.

When do you consult Orthopaedics?

This patient can follow up with orthopedics in clinic. In the case of an associated elbow dislocation with a displaced coronoid fracture, comminuted fracture, or a bony fragment in the joint space, orthopedics should be consulted to evaluate for open reduction [1,2]. Orthopedics should also be consulted for terrible triad injuries and open fractures [4]. 

• Pearl: Type 1 fractures without instability can usually be managed conservatively with immobilization and close orthopedic surgery follow up [5]. However, if there is instability associated with a Type 1 fracture, surgery may be indicated [1,4,6]. Type 2 and 3 fractures are typically considered unstable and will often need operative intervention [1,6].