Fractures of the radial head are common injuries in adults. Fractures of the radial neck are common in children. Radial head fractures are usually caused by falling onto an outstretched hand.
Important associated injuries include; MCL rupture (can cause valgus instability), dislocation of the DRUJ with Essex Lopresti, and terrible triad. The terrible triad consists of a radial head fracture, MCL rupture, and coronoid process fracture.
Making the diagnosis can be difficult. The physician may need to obtain radiocapitellar views to make the diagnosis. The forearm is placed in neutral and the x-ray angle is 45° cephalad.
Radial Head Fractures are classified into four types:
Type I—Nondisplaced fracture, early range of motion and no surgical treatment
Type II - Partial articular fracture with displacement, less than 30% or displaced more than 2 mm. Both screws and plates are used in fixation of the bone.
Type III—Identified as a comminuted fracture involving the entire radial head. Reduction and fixation is used if stable fixation can be achieved. Early excision can be done in Type III for isolated cases with only 2mm proximal migration. It is important to monitor the patient for wrist pain.
Type IV—occurs when a fracture of the radial head is associated with a dislocation of the elbow joint. Fixation can be done with either a plate or screws. If fixation cannot be achieved, then the prosthetic replacement must be done. An excision of the radial head alone is contraindicated in elbow dislocation.
Unusual injury consisting of a radial head fracture, distal radioulnar joint (DRUJ) injury and interosseous membrane rupture is referred to as an Essex Lopresti Lesion. Typical treatment for this injury includes a fixation or replacement of the radial head. It is also important to assess the instability of the DRUJ as pinning of the DRUJ in supination may be necessary if the joint is unstable.
Surgery for the radial head fractures is done through posterolateral (Kocher) approach between the ECU and Anconeus muscles or through the lateral approach. It is crucial to monitor the safe zone for implant insertion to avoid impingement and loss of rotation.
