Fractures of the olecranon

Fractures of the Olecranon

Muhammad Abdelghani

Epidemiology

• Bimodal distribution:– Younger individuals: High-energy trauma –Older individuals: Simple falls

Anatomy

• The subcutaneous position of olecranon makes it vulnerable to direct trauma.

Anatomy

• The coronoid process delineates the distal border of greater sigmoid notch of ulna, which articulates with the trochlea.

• This articulation allows motion only about the flexion-extension axis, thus providing intrinsic stability to the elbow joint.

• “Bare area”: Transverse ridge interrupting the articular cartilage.

Anatomy

• Posteriorly, the triceps tendon envelops the articular capsule before it inserts onto the olecranon. • Fracture olecranon with displacement

represents a functional disruption of triceps mechanism, resulting in loss of active extension of the elbow.

Mechanism of injury

• Direct: Fall on the point of elbow or direct trauma to olecranon.– Typically results in a comminuted olecranon fracture.

• Indirect: Fall onto the outstretched upper extremity accompanied by a strong, sudden contraction of triceps.– Typically results in a transverse or oblique fracture.

• A combination of these may produce displaced, comminuted fractures, or, in cases of extreme violence, fracture-dislocation with anterior displacement of the distal ulnar fragment and radial head.

Clinical Presentation

• Patients typically present with the upper extremity supported by the contralateral hand with the elbow in relative flexion.

Clinical Evaluation• Look: – Abrasions over olecranon or hand can be indicative of the

mechanism of injury.

• Feel:– Palpable defect at fracture site.

• Move:– Inability to extend the elbow actively against gravity indicates

discontinuity of triceps mechanism.

• Neurosensory evaluation: – Associated ulnar nerve injury is possible, esp. with

comminuted fractures resulting from high-energy injuries.

Radiographic Evaluation

• True lateral radiograph: –Demonstrates:• extent of the fracture• degree of comminution• degree of articular surface

involvement• displacement of the radial head, if

present.


• AP view: –This should be evaluated to

exclude associated fractures or dislocations. –The distal humerus may obscure

osseous details of the olecranon fracture.


• Radiocapitellar view: –This may be of help if the patient appears to have

a concomitant injury or displacement of the radial head. –Position the patient as for a lateral x-ray view but

angle the tube 45° toward the shoulder

Mayo Classification

• This distinguishes 3 factors that have a direct influence on treatment:

(1) fracture displacement,

(2) comminution, &

(3) ulnohumeral stability.

Mayo Classification

• Type I: nondisplaced or minimally displaced:– Subcategories: Noncomminuted (IA); Comminuted (IB). – Treatment: Nonoperative.

• Type II: displaced proximal fragment without elbow instability:– Subcategories:

• IIA: noncomminuted, can be treated by tension band wire fixation.

• IIB: comminuted & require plate fixation.– Treatment: Operative.

• Type III: features instability of the ulnohumeral joint. – Treatment: Operative.

Schatzker classification (Based on Fracture Pattern)

• Transverse: Occurs at apex of sigmoid notch. Usually represents an avulsion fracture.

• Transverse-impacted: A direct force leads to comminution & depression of articular surface.

• Oblique: results from hyperextension injury; it begins at midpoint of sigmoid notch and runs distally.

• Comminuted fractures with associated injuries: result from direct high-energy trauma; fractures of coronoid process may lead to instability.

• Oblique-distal: Fractures extend distal to the coronoid & compromise elbow stability.

• Fracture-dislocation: usually associated with severe trauma.

Treatment

Treatment objectives

• Restoration of articular surface• Restoration & preservation of elbow

extensor mechanism• Restoration of elbow motion & prevention

of stiffness• Prevention of complications

Nonoperative Treatment

• Indications:–nondisplaced fractures –displaced fractures in

poorly functioning older individuals


• Immobilization in a long arm cast with the elbow in 45-90° of flexion is favored by many authors.

• In reliable patients a posterior splint or orthosis with gradual initiation of ROM after 5-7 days may be used.

• Follow-up radiographs should be obtained within 5-7 days after treatment to rule out fracture displacement.


• Osseous union is usually not complete until 6-8 weeks.• In general, there is adequate fracture stability

at 3 weeks to remove the cast and to allow protected ROM exercises, avoiding flexion past 90°.

Operative Treatment

• Indications:–Disruption of extensor mechanism (any

displaced fracture)–Articular incongruity–Open fractures

Principles of Surgical Treatment

• Rigid fixation is required.a) Plate fixation:

• Often the best choice, esp. when comminution is present, to maintain ulnar length and alignment.

• A number of plate fixation techniques have been described, most involving a contoured posterior or lateral plate with, when possible, interfragmentary screws.

a) In addition to internal fixation, use of an external fixation device or distraction device can be helpful or necessary to maintain joint congruity while allowing an early motion program.


• Primary bone grafting should be considered to reduce the risk of nonunion, especially in a type IIIB olecranon fracture.


• Total elbow arthroplasty may be considered based on the fracture pattern, bone quality, and patient age. – However, the results of elbow arthroplasty

following trauma are not as good as the results for patients with inflammatory arthritis.


• Restoration of articular congruity is a primary goal of reduction and fixation of olecranon fractures.

1) Type IIIB olecranon fractures are not well suited to tension band wiring because of the loss of bony stability under compression.

2) Avoid narrowing of the olecranon to coronoid distance.

3) It is usually preferable to co-apt the cortical surfaces and leave a gap in the articular surface in order to preserve a more normal articular contour.

Surgical options Tension band wiring

• Commonly used for noncomminuted, transverse olecranon fractures.

• Tension band wiring in combination with 2 parallel K-wires counteracts the tensile forces & converts them to compressive forces and is indicated for avulsion-type olecranon fractures.

• Various techniques have been described.

Surgical options Tension band wiring

Standard AO technique: • This technique uses 2 intramedullary K-wires and a

figure-of-eight wire with a single knot.• To avoid proximal migration and hardware prominence,

the K-wires can be directed anteriorly to engage the ulnar cortex at the base of the coronoid.a) This provides stronger fixation than the usual intramedullary

placement of the K-wires.b) Some concerns have been raised over the potential for

neurovascular injury with this technique, although no reports of such injuries could be found.

Intramedullary placement of K-wires.

Transcortical placement of K-wires

Two different techniques of tension band wiring of the olecranon

Surgical options Intramedullary fixation

• Currently, the accessibility and ease of cannulated screw systems have made intramedullary screw fixation an attractive treatment option.

• Indications for intramedullary screw placement: – Similar to tension band wiring.– Include simple, noncomminuted

transverse fracture patterns.


• 6.5-mm cancellous lag screw fixation.

• The screw must be of sufficient length to engage the distal intramedullary canal for adequate fixation.

• This may be used in conjunction with tension band wiring.


• Other forms of intramedullary fixation have also been introduced. – Interlocking intramedullary nailing

devices have been created to treat simple, transverse olecranon fractures.

• Proponents of this device have touted its “locking” capability which prevents the need for intramedullary cortical purchase necessary in traditional screw techniques.

Surgical options Plate and screws

• Plating has become an increasingly important method of treating displaced olecranon fractures.


• Although plate fixation can be used for virtually any type of olecranon fracture, it is ideal for the following indications: – comminuted olecranon fractures – Monteggia fracture-dislocations– olecranon fracture-dislocations

• A plate should also be for oblique fractures and for fractures that extend distal to the coronoid.


• Low-profile, locking precontoured plates are now available.

• Standard manually contoured 3.5-mm limited contact DCPs are also available.


• Plate fixation allows neutralization of forces across the fracture site and should provide adequate rigid internal fixation to begin early motion.

• Interfragmentary compression screws should be utilized when possible.

• Augmentation with an external fixation or distraction device may be beneficial when elbow stability is lacking despite fracture fixation.

• Articular step-off of > 2 mm has been associated with poorer results.


Plate position– Most authors prefer posterior

placement of the plate.– However, King found no significant

difference in strength of fixation between posterior or lateral placement.

• Posterior plating allows a more direct approach to the proximal ulna and requires less soft tissue stripping and less effort to contour the plate.

• A laterally placed plate may be less prominent and less likely to require hardware removal.

Hook plate

One end of a 3.5-mm semitubular plate is

flattened with a mallet and bending irons

A wire cutter is used to cut away a portion of the distal plate hole

The two cut ends are then bent to 90°.

The plate is then contoured to the olecranon. Two holes are placed in the proximal olecranon to ease insertion of the hooks into the fragment

Cut portions of the plate are bent 90 degrees

Surgical optionsFragment Excision with Triceps Advancement

• Recent advances in implant technology have made reconstruction of a severely comminuted olecranon fracture more feasible.

• However, proximal fragment excision and triceps advancement still constitutes a viable option in the treatment of comminuted olecranon fractures.

• Excision of as much as 50% of the olecranon is effective in treating comminuted fractures.


• Indications:– Nonunited fractures– Extensively comminuted

fractures– Fractures in elderly individuals

with severe osteopenia and low functional requirements

– Extraarticular fractures


• Pearls and Pitfalls:– Excision in patients with > 60% articular involvement

yields poorer results.– When reattaching the triceps, care should be taken to

bring the tendon close to the articular surface, thus improving stability by acting as a sling for the trochlea.

– Patients must have an intact MCL, interosseous membrane, and DRUJ before excision, or instability will likely develop.

– A major criticism of this technique is the potential for significant loss of triceps power.


• Contraindications: – Fracture-dislocations of the elbow– Fractures of the radial head

(Excision will compromise elbow stability)

Surgical optionsTotal Elbow Arthroplasty

• Indications:– Total elbow arthroplasty may be considered in

elderly patients with significant comminution and > 60% articular involvement.

Summary of Treatment by Mayo Fracture Type

• Type I: nondisplaced or minimally displaced, subclassified as either noncomminuted (IA) or comminuted (type IB).

• Treatment: – Casting or splinting and early

mobilization.a. Long arm cast or posterior splint: used for

comfort and protection, preferably in a position of mid-flexion and neutral forearm rotation.

b. Dynamic extension splint: can also be used for early motion with active flexion and passive extension.

c. Motion can often begin by 7 days post-injury with weekly radiographs during the first few weeks to follow the fracture and confirm that it remain nondisplaced.


• Type II: displaced proximal fragment without elbow instability.

• Treatment: – Articular incongruity,

exacerbated by the deforming forces of the triceps, biceps and brachialis muscles, makes surgery necessary to restore the articular surface, prevent redisplacement and allow early motion.


• Type IIA: noncomminuted

• Treatment: – Tension band wiring: several methods

• This allows neutralization of the deforming forces and compression of the fracture site.

– Longitudinal intramedullary fixation: has also been advocated for this fracture pattern; however, higher rates of displacement, poor rotational control, and problems with screw purchase in the medullary canal have been reported. • The technique works best with a single large

fragment and minimal or no comminution.


• Type IIB: comminuted

• Treatment: – The nature of these fractures creates

increased difficulty obtaining articular congruity with tension band wire techniques.

– Additional interfragmentary screw fixation or plate fixation can improve the results in these fractures.

– Fragment excision and triceps advancement may be considered, particularly for small fragments or in elderly patients.


• Type III: Olecranon fracture with instability of the ulnohumeral joint

• Treatment: – These fractures present the greatest challenge

and have the highest rate of complications.• The elbow is unstable, usually with anterior

subluxation of the radius and ulna on the distal humerus as a result of the deforming forces created by the triceps, biceps, and brachialis.

• These fractures are usually comminuted (type IIIB).• These fracture carry a high incidence of additional

elbow trauma.a) Concomitant injuries include radial head fractures,

distal humerus fractures, and ligament rupture.

b) Concomitant injuries should be assessed and treated at the same time as the olecranon fracture because they have tremendous impact on the results achieved.

Postoperative management

• The patient should be placed in a posterior elbow splint. • With a stable repair, initiate early ROM

exercises.• In cases with severe soft tissue injury, early

motion may need to be delayed until the soft tissue healing is adequate to tolerate motion.

Complications.

• Hardware prominence requiring removal:– The most common complication (up to 80%).–More common with tension band wiring than

with plate fixation.

Complications

• Hardware failure (1%-5%).• Infection (0%-6%).• Pin migration (15%).• Ulnar neuritis (2%-12%).• Heterotopic ossification (2%-13%).• Nonunion (5%).• Decreased ROM (Stiffness): may complicate up to 50% of

cases. Loss of elbow extension is most common.

Health & Medicine

Fractures of the olecranon