Radiography
Standard anteroposterior (AP) and lateral radiographs of the elbow are sufficient for evaluation of isolated olecranon fractures. Direct supervision of the x-ray process may be necessary to ensure that true AP and lateral radiographs are obtained. The radiocapitellar view may be helpful for delineation of the radial head and capitellar fractures. (See the images below.)
Lateral radiograph of elbow in 78-year-old man who fell on his outstretched hand. Displaced fracture of olecranon was noted.
MRI may be necessary to diagnose an olecranon stress fracture that may not be seen on plain radiographs. [6]
Staging
Classification helps decide treatment options. Both acute fractures and stress fractures occur. Several classification systems have been suggested for acute fractures.
The Arbeitsgemeinschaft für Osteosynthesefragen (AO)/Association for the Study of Internal Fixation (ASIF) classification, used by the Orthopaedic Trauma Association (OTA), divided these fractures into three broad categories, as follows [12] :
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Type A - Extra-articular fractures
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Type B - Intra-articular fractures
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Type C - Intra-articular fractures of both the radial head and the olecranon
Schatzker developed a classification with six types, as follows (types A, B, and C are intra-articular fractures) [13] :
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Type A - Simple transverse fracture
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Type B - Transverse impacted fracture
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Type C - Oblique fracture
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Type D - Comminuted fracture
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Type E - More distal fracture, which actually is extra-articular
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Type F - Fracture dislocation
Colton developed a classification with four fracture types, as follows:
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Type I - Avulsion
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Type II - Oblique
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Type III - Associated dislocation of the elbow
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Type IV - Multisegmented
The Mayo Clinic classification specified three fracture types, as follows [14] :
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Type I - Nondisplaced (12%)
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Type II - Displaced but stable (82%)
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Type III - Associated instability of the elbow (6%)
Benetton et al studied these four systems of classifying olecranon fractures with a view to determing their intraobserver and interobserver reliability. [15] They noted the following findings:
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Colton classification - Substantial intraobserver and interobserver agreement for specialists and nonspecialists
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Schatzker classification - Fair agreement for both specialists and nonspecialists
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Mayo classification - Fair concordance for both specialists and nonspecialists
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AO-ASIF classification - Moderate agreement for specialists; slight intraobserver agreement for nonspecialists
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Lateral radiograph of elbow in 78-year-old man who fell on his outstretched hand. Displaced fracture of olecranon was noted.
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Drawing depicting radial bow of proximal third of ulna.
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Anteroposterior radiograph following reduction and internal fixation of fracture with 7.3-mm cannulated screw and 1.6-mm cable.
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Lateral radiograph demonstrating threads of screw engaging cortices of ulna.
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Typical relatively transverse olecranon fracture.
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Pediatric olecranon fracture.
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Olecranon process consists of bone of proximal ulna from base of coronoid process (down arrow) proximally. Trochlear notch (up arrows; also called semilunar notch) is articular surface shown between two arrows.
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Incorrect tension band technique: pins should be anchored in anterior cortex and not placed down medullary canal.
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Transverse olecranon fracture without comminution.
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Transverse olecranon fracture treated with tension band technique (ideally, both K-wires should have been anchored in anterior cortex).
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Lateral plate position for olecranon fracture fixation.
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Posterior plate position for olecranon fracture.
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Example of distal olecranon fracture.
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Plate fixation of distal olecranon fracture.
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Comminuted olecranon fracture.
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Plate fixation of comminuted olecranon fracture.
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Example of specialized olecranon plate.
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20-year-old man with comminuted olecranon fracture extending distally into ulnar shaft from gunshot injury.
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Bridge plating of comminuted olecranon fracture extending into proximal ulna diaphysis after gunshot injury.
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Monteggia-variant fracture-dislocation: olecranon and radial head fractures.
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Monteggia-variant fracture-dislocation treated with fixation of both fractures.
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Monteggia-variant fracture of proximal ulna and radial head.
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Monteggia-variant fracture-dislocation treated with plate fixation of olecranon and proximal ulna and replacement of radial head.
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Example of intramedullary screw fixation of olecranon fracture. In this case, screw diameter was too small and loss of fixation has occurred.
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Intramedullary rod fixation of olecranon osteotomy used in repair of distal humerus fracture.
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79-year-old man with olecranon fracture.
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AP radiograph of tension band wiring of olecranon fracture in 79-year-old man.
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Lateral radiograph of tension band wiring in 79-year-old man with olecranon fracture. Note excellent technique with anatomic reduction, K-wires anchored in anterior cortex, and tension band wire placed dorsally.
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Nonunion of olecranon fracture in 79-year-old man despite excellent tension band wiring technique.
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Excision of olecranon after nonunion of fracture in 79-year-old man.
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Comminuted olecranon fracture.
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Comminuted olecranon fracture plated with proximal edge off bone to allow two more screws in proximal segment and fixed angled intramedullary screw (bending plate distorts locking hole).
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Healed comminuted olecranon fracture after removal of prominent plate fixation.
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Olecranon nonunion after nonoperative treatment.
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Repair of olecranon nonunion with double-plate technique (original fracture was treated nonoperatively).
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AP radiograph of healed olecranon nonunion after original nonoperative treatment; repaired with double-plate technique.
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Lateral radiograph of healed olecranon nonunion after original nonoperative treatment; repaired with double-plate technique.
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MRI showing olecranon stress fracture.
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Use of pins to raft joint surface of comminuted olecranon fracture with plate fixation of fracture as well.
