Elbow fractures and dislocation in adults

INTRODUCTION — Elbow fractures and dislocations are common injuries managed in clinics and emergency departments. The presentation, evaluation, and basic management of adults with elbow fractures not involving the radial head and neck are reviewed here. The evaluation and management of other upper extremity injuries in adults and of elbow injuries in children are discussed separately.

●Pediatric elbow injuries (see "Elbow anatomy and radiographic diagnosis of elbow fracture in children" and "Elbow injuries in active children or skeletally immature adolescents: Approach")

●Adult elbow injury assessment (see "Evaluation of elbow pain in adults" and "Musculoskeletal ultrasound of the elbow")

●Adult upper extremity fractures near elbow (see "Radial head and neck fractures in adults" and "Midshaft ulna and radius fractures in adults" and "Midshaft humerus fractures in adults")

●Adult non-fracture elbow injuries (see "Elbow tendinopathy (tennis and golf elbow)" and "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach")

GENERAL EPIDEMIOLOGY — Fractures around the elbow joint account for approximately 5 percent of all fractures [1,2]. Injury patterns for children and adults are quite different. Adult fractures are more commonly intra-articular and occur following a fall (>60 percent) or during sport or recreational activity (>15 percent). (See "Elbow injuries in active children or skeletally immature adolescents: Approach" and "Elbow anatomy and radiographic diagnosis of elbow fracture in children".)

Radial head and neck fractures constitute approximately one-third of elbow fractures in adults. These are reviewed separately. (See "Radial head and neck fractures in adults".)

Fractures of the olecranon account for 20 percent of proximal forearm fractures and 10 percent of all upper extremity fractures [1]. Distal humerus fractures comprise approximately 2 percent of all fractures but one-third of elbow fractures in patients over 60 years of age [2,3]. Isolated coronoid or medial epicondyle fractures are rare but can occur with elbow dislocations. Isolated capitellar, trochlear, or medial epicondyle fractures are also rare but may occur in combination, although such injuries remain relatively uncommon.

CLINICAL ANATOMY — Elbow anatomy is reviewed in greater detail separately (figure 1 and figure 2); aspects of the anatomy of special importance to specific injuries are discussed below. (See "Evaluation of elbow pain in adults", section on 'Clinical anatomy'.)

RADIAL HEAD AND NECK FRACTURES — Fractures of the radial head and neck are common injuries in adults of all ages. Patients present with lateral elbow pain and a history of a fall onto an outstretched hand or direct trauma to the elbow. Examination typically reveals focal tenderness, swelling over the lateral elbow, and often decreased elbow motion. These injuries are discussed in detail separately. (See "Radial head and neck fractures in adults".)

DISTAL HUMERUS ARTICULAR FRACTURES

Anatomy, mechanism, and clinical presentation — In adults, the elbow can be conceptualized as a ring with medial, lateral, anterior, and posterior columns [4]:

●Medial column: Medial collateral ligament complex, coronoid process, medial condyle and epicondyle

●Lateral column: Radial head, capitellum, lateral collateral ligament complex

●Anterior column: Boney buttress (coronoid process, radial head), anterior joint capsule, brachialis

●Posterior column: Olecranon, posterior joint capsule, distal triceps tendon

Distal humerus fractures include extra-articular supracondylar and transcondylar fractures, single-column fractures, two-column (ie, bicolumnar) fractures, and coronal shear fractures. These injuries typically occur from high-energy trauma in young adults but from low-energy falls (eg, from standing) in older adults [5]. Distal humerus fractures are increasing in frequency among adults over age 50, and these patients should be worked up for osteoporosis [6]. (See "Clinical manifestations, diagnosis, and evaluation of osteoporosis in postmenopausal women".)

Distal humerus fractures usually result from forces driving the proximal ulna or radial head into the articular surface of the trochlea or capitellum (or both), causing a comminuted intra-articular fracture pattern. Single-column fractures involve a varus or valgus force placed on an elbow in extension and are associated with ligamentous injury of the contralateral side [3]. Otherwise, these injuries tend to present in similar fashion, and fracture patterns cannot be distinguished based on patient history.

Physical examination — Examination reveals tenderness, ecchymosis, swelling that obscures the elbow's anatomic landmarks, and diminished joint motion [7]. In particular, restricted elbow extension suggests elbow fracture. Pain and swelling may be sufficiently severe that patients are unable or unwilling to move the elbow joint at all.

Conversely, the patient who is able to perform full elbow extension is unlikely to have sustained an elbow fracture [8]. In a prospective, multicenter study involving over 1700 patients with acute elbow injury, 602 patients were able to fully extend their elbow, and of these, only 17 had sustained a fracture. Overall, the sensitivity of the elbow extension test for detecting elbow fracture was 96.8 percent (95% CI 95.0-98.2).

Following injury, the distal brachial artery is at risk for entrapment between the bicipital aponeurosis and fracture fragments, which may cause arterial compression, spasm, intimal tear, or thrombosis [9]. Thus, close attention to vascular function is required, and distal pulses should be palpated at the time of injury and following any procedure, including splinting or casting. The robust collateral circulation of the distal forearm and wrist means the presentation of vascular injury may be subtle [9]. A diminished pulse or decreased capillary refill represents an orthopedic emergency and warrants thorough evaluation (eg, computed tomography angiography [CTA]) [9]. (See "Overview of upper extremity ischemia".)

Median (figure 3) or ulnar (figure 4) nerve injury may occur in up to 25 percent of cases [10]. Neurologic examination including assessment of motor and sensory (eg, two-point discrimination) function is required and should be repeated following any manipulation of the fracture (eg, reduction, splinting). (See "Traumatic peripheral neuropathies".)

Acute compartment syndrome is a rare complication of isolated distal humerus fractures but is more likely with concomitant crush injuries, burns, or fractures of the distal forearm or forearm shaft [11-13]. Thus, it is important to look for associated fractures of the forearm. Notable symptoms and signs associated with acute compartment syndrome are severe pain and swollen, tense muscle compartments. (See "Acute compartment syndrome of the extremities".)

Diagnostic imaging — Standard plain radiographs of the elbow (image 1 and image 2 and image 3 and figure 5) should be obtained, including anterior-posterior (AP) and lateral views. The radiohumeral and humeroulnar joints are well visualized on the AP view. The capitellum, olecranon, and humeral condyles are best seen on the lateral view.

When necessary to better visualize the capitellum, an AP view with the elbow flexed to 40 degrees (which disengages the olecranon from the fossa) can be obtained [14,15].

While traction radiographs allow a better view of the distal humerus, they cause undue pain, and their use for surgical planning has been superseded by computed tomography (CT). As many distal humerus fractures involve intra-articular injury, CT is usually obtained to define fracture displacement and comminution, and to guide surgical management [16].

Bedside ultrasound may serve as a useful preliminary screening study. In addition to overt fractures, it may reveal a posterior elbow fat pad consistent with occult elbow fracture [17]. Doppler ultrasound may help to assess blood flow.

Classification — The AO classification system is widely used for research but not for nonoperative clinical management [18]. For non-surgeons, a useful classification involves the following:

●Extra-articular fractures (supracondylar (image 4), transcondylar, and isolated epicondyle)

●Single-column fractures (medial and lateral), which can be subdivided using the Milch classification:

•Milch type I are isolated fractures of the lateral condyle that do not extend into the trochlear groove; these may be amenable to nonoperative management by non-surgeons

•Milch type II fractures extend medially into the trochlear groove, rendering the elbow unstable

●Two-column (bicolumnar) fractures (most common)

Indications for orthopedic consultation — Emergency (ie, immediate) surgical consultation is necessary for any signs of vascular compromise and for all open fractures. In addition, the surgeon should be notified immediately of any associated nerve injury; surgery may be delayed in such cases.

Timely surgical consultation, typically within three days, should be obtained for all other distal humerus fractures [14]. Complication rates as high as 60 percent are reported for fractures treated nonoperatively, and such management should only be considered for uncomplicated, nondisplaced fractures and for injuries in patients deemed unsafe or otherwise inappropriate for surgery because of extremely limited physical requirements (eg, bedridden patient with minimal physical demands) [5].

Injuries that may be suitable for nonoperative treatment include single-column Milch type I fractures and isolated avulsion fractures of the medial or lateral epicondyle. Such fractures are rare, and there is little evidence to guide conservative treatment.

Restoring joint integrity in older adults with distal humerus fractures is challenging due to poor bone quality and complex anatomy. Surgical options include open reduction and internal fixation or arthroplasty. Arthroplasty has lower complication rates and is the preferred technique for comminuted, intra-articular fractures.

Initial management — Pending surgical consultation, distal humerus fractures can be immobilized in a posterior, long-arm splint with the elbow at 90 degrees of flexion and the forearm in neutral position (ie, without supination or pronation) [14]. The posterior splint extends from the level of the axilla to that of the proximal palmar crease. A sling is used for comfort and to support the splint. Otherwise, standard interventions for acute fracture management should be implemented, including appropriate analgesia. (See "General principles of acute fracture management".)

Surgical consultation is required for all distal humerus fractures except for uncomplicated nondisplaced fractures or injuries in patients deemed unsafe or otherwise inappropriate for surgery. (See 'Indications for orthopedic consultation' above.)

Complications — Ulnar nerve injury occurs in up to 20 percent of patients. Neuropraxia accounts for the large majority of such injuries, and 90 percent resolve spontaneously [9,19]. Most injuries stem from the proximity of the nerve to fracture fragments, but injury may also occur during surgery when the nerve is mobilized and retracted [9]. (See "Traumatic peripheral neuropathies" and "General principles of fracture management: Early and late complications".)

Vascular injuries are rare but associated with significant morbidity if untreated. Complications stemming from vascular compromise most often include nonunion, malunion, or osteonecrosis, which may be due to compromised blood flow at a so-called vascular "watershed" (area of bone supplied by small branches of two arteries). Other rare complications include Volkmann contracture stemming from compartment syndrome of the forearm and gangrene, resulting in loss of the limb. (See "Pathophysiology, classification, and causes of acute extremity compartment syndrome".)

Return to sport and work — Surgery and postoperative rehabilitation are intended to restore joint integrity and mobility as early as possible. In most cases, rehabilitation guidelines emphasize early range of motion. The time required to return to sport or physically demanding work varies depending upon the severity of the injuries sustained and the sport or occupation. Most people can return to a desk job within two to four weeks, but heavy physical laborers usually require about three months. Athletes who play a contact sport require four to six months. Most patients can resume driving in 6 to 12 weeks.

CORONAL SHEAR FRACTURES

Anatomy, mechanism, and clinical presentation — Coronal shear fractures are a type of distal humerus injury that includes a fracture of the trochlea, the capitellum, or both. These fractures account for only 6 percent of distal humerus fractures and 1 percent of elbow fractures [14].

The trochlea and capitellum project 40 degrees anteriorly from the axis of the humerus [5]. Because of this anterior position, falls onto an outstretched hand cause the radial head to exert a shear force at the capitellum, causing fracture fragments to displace anteriorly. A fall onto a flexed elbow causes the proximal ulna to create a similar shear force, but fragments of the trochlea are displaced posteriorly [3].

Physical examination — Patients with coronal shear fractures typically hold their elbow in flexion. The area is tender and there is diminished joint motion due to pain, swelling, and a mechanical block from intra-articular fracture fragments.

Up to 60 percent of coronal shear fractures have an associated injury, most often a radial head or olecranon fracture or collateral ligament tear [14]. Assessment for these associated injuries includes gentle palpation of the radial head and neck and valgus-varus stress testing of the elbow, if feasible, although pain may prevent such testing. Bedside ultrasound can be useful for assessing ligament integrity, including dynamic assessment if pain permits.

As shear fractures may be associated with an elbow dislocation, patients should be assessed for such injury. (See 'Elbow dislocation' below.)

Diagnostic imaging — Standard plain radiographs of the elbow (image 1 and image 2 and image 3 and figure 5) should be obtained, including anterior-posterior (AP) and lateral views. A lateral elbow radiograph may exhibit a "double arc" sign at the capitellum (image 5), suggestive of an underlying fracture [20].

Isolated fracture of the articular cartilage rim (type II capitellar fracture, Bryan and Morrey classification) may be missed on standard radiographs. A posterior fat pad (associated with clinical loss of elbow motion) may be the only radiographic finding.

Computed tomography (CT) may be needed to characterize the fractures. The Bryan and Morrey classification scheme for capitellar fractures is used to guide surgical technique but does not alter the need for surgical intervention [20].

Indications for orthopedic consultation — Emergency (ie, immediate) surgical consultation is necessary for any signs of vascular compromise or nerve injury and for all open fractures.

Timely surgical consultation, typically within three days, should be obtained for all other coronal shear fractures.

Management — Pending surgical consultation, fractures can be immobilized in a posterior, long-arm splint with the forearm in neutral position (ie, without supination or pronation). (See 'Initial management' above.)

Coronal shear fractures are intra-articular and susceptible to displacement, which may cause a mechanical block to elbow motion. To avoid such complications, operative fixation is the usual treatment.

Complications — As with other distal humerus fractures, potential complications include nonunion, malunion, and osteonecrosis. Other possible complications from missed coronal shear fractures include diminished elbow motion, instability, and post-traumatic arthritis. (See "General principles of fracture management: Early and late complications".)

Return to sport and work — Return to activity is accomplished in a stepwise fashion under the direction of the orthopedic surgeon and physical therapist.

OLECRANON FRACTURES

Anatomy, mechanism, and clinical presentation — The olecranon enables elbow flexion and extension while preventing anterior translation of the ulna. The olecranon's superficial location makes it vulnerable to direct trauma. All three heads of the triceps muscle insert on the olecranon, and thus, fracture impairs elbow extension [21]. A pathognomonic sign of a complete olecranon fracture is inability to extend the elbow.

Olecranon fractures are usually sustained from a direct fall or blow to the elbow. This causes forceful compression of the olecranon against the distal humerus, causing displaced fractures [22]. An alternative mechanism involves a fall onto an outstretched hand, which can cause vigorous contraction of the triceps and produce a transverse olecranon fracture [23].

Physical examination — Patients complain of posterior elbow pain. Palpation reveals focal tenderness at the olecranon, and a bony defect may be identified. Associated dislocation of the radial head (Monteggia fracture) can occur, and the radial head should be palpated. (See 'Monteggia fracture in adults' below.)

Olecranon fracture can impair triceps function and, if possible, elbow extension should be assessed. The best way to do so is by resting the upper extremity on a table or other level surface with the shoulder abducted to about 90 degrees and the elbow somewhat flexed. This removes the contribution of gravity when the patient is asked to straighten their elbow. Total inability to extend the elbow suggests complete disruption of the triceps mechanism.

Given the superficial course of the ulnar nerve along the medial aspect of the elbow, examination should include assessment of nerve function, including sensation (figure 6) and motor function (figure 4 and picture 1).

Diagnostic imaging — Standard plain radiographs of the elbow (image 1 and image 2 and image 3 and figure 5) should be obtained, including anterior-posterior (AP) and lateral views. A true lateral plain radiograph of the elbow is needed to diagnose an olecranon fracture and to define the extent of any comminution, displacement, and intra-articular involvement (image 6) [24]. Clinicians should look closely for associated injuries to the coronoid and radial head.

Typically, by the age of 14 years, the olecranon ossification center has fused with the proximal ulna (figure 7) [25]. However, in some cases, the physis can persist into adulthood and may be mistaken for a fracture [25]. Comparison radiographs of the unaffected side and the absence of a posterior fat pad can help to distinguish a persistent physis from a fracture.

Classification — The Mayo classification is used to guide treatment and determine the need for orthopedic consultation. Fractures are defined as type I, II, or III based on displacement and elbow stability. Each type can be subclassified A (noncomminuted) or B (comminuted).

●Type I fractures are nondisplaced with an intact extensor mechanism. These can be managed nonoperatively.

●Type II fractures are displaced, but the collateral ligaments are intact. These are most common, accounting for up to 85 percent of injuries [26].

●Type III fractures are displaced and comminuted. These are commonly associated with ligamentous injury, radial head fracture, or coronoid fracture. Type III fractures represent an unstable elbow joint that requires surgical repair [26].

Indications for orthopedic consultation — Emergency (ie, immediate) surgical consultation is necessary for any signs of vascular injury and for all open fractures. In addition, the surgeon should be notified immediately of any associated nerve injury; surgery may be delayed in such cases.

Except for small avulsion fractures, all olecranon fractures are intra-articular, and thus, anatomic alignment to ensure proper joint function is a primary consideration [27]. Therefore, early orthopedic consultation (within three days) should be obtained for all olecranon fractures aside from small extra-articular avulsion fractures not affecting joint motion. Most olecranon fractures, and all Mayo types II and III fractures, require surgical intervention to ensure precise anatomic reduction, joint integrity and stability, and full elbow extension [24,27]. Some patients may function adequately without surgical repair, but the surgeon should be involved in making this determination [28].

Initial management — Type I fractures with an intact extensor mechanism can be managed nonoperatively in a posterior, long-arm splint with the elbow in 45 to 90 degrees of flexion and the forearm in neutral position (ie, without pronation or supination) [21,24].

Once acute swelling has subsided, the splint can be replaced with a long-arm cast for three to four weeks, after which the patient should be referred to physical therapy to help regain motion and strength. Weekly follow-up, with plain radiographs obtained at each visit, is required, as type I fractures may become displaced by the distracting force exerted by the triceps [27].

Closed type II and III olecranon fractures can be immobilized in a long-arm splint pending orthopedic consultation. While most elbow fractures are placed in 90 degrees of flexion, olecranon fractures can be splinted in 45 degrees of flexion to improve fracture reduction [21,26].

CORONOID FRACTURES

Anatomy, mechanism, and clinical presentation — The coronoid process of the proximal ulna lies anterior to the ulnar-humeral joint and acts as a buttress preventing posterior subluxation or dislocation of the ulna. The anterior bundle of the medial collateral ligament (MCL) attaches to the coronoid process and forms part of the anterior capsule of the elbow joint.

Fractures of the coronoid are caused by a variety of mechanisms but rarely occur in isolation. Most commonly, an axial force exerted on an extended elbow loads the articular surface of the coronoid process, and twisting or flexion causes the trochlea to shear off the coronoid process.

Coronoid process fractures frequently accompany elbow dislocation, which may also involve fracture of the radial head. Elbow dislocation and its associated injuries and radial head fractures are discussed in greater detail below. (See 'Elbow dislocation' below and "Radial head and neck fractures in adults".)

Another common mechanism of injury involves posteromedial rotatory displacement caused by a varus stress to the elbow. This leads to a fracture of the anteromedial aspect of the coronoid process.

Physical examination — Coronoid fractures are often associated with an elbow dislocation. If the elbow has not spontaneously reduced, the patient complains of significant pain, while the elbow manifests obvious deformity and extremely limited motion. (See 'Elbow dislocation' below.)

If the elbow has spontaneously reduced, the patient may have an isolated coronoid fracture and may report sustaining an injury that caused a sensation of the elbow being unstable [29]. The elbow will be diffusely swollen with tenderness at the antecubital fossa.

Neurovascular examination of the injured extremity should be performed before any manipulation (eg, reduction of dislocation) or range of motion testing.

Diagnostic imaging — Plain radiographs of the elbow should be obtained (image 1 and image 2 and image 3 and figure 5), including anterior-posterior (AP), lateral, and, if possible, oblique views (image 7). In a true lateral view, the radial head and coronoid overlap, complicating interpretation. The oblique view avoids such overlap, allowing clear visualization of the radial head and the coronoid and enabling clinicians to identify minimally displaced fractures. If a fracture is suspected but not apparent on plain radiographs, computed tomography (CT) can be obtained.

Classification — There are two main classification systems for coronoid fractures.

The Regan and Morrey classification describes three fracture types [30]:

●Type I – Fracture involves only the tip of the coronoid

●Type II – Fracture involves more than the tip but less than 50 percent of the coronoid

●Type III – Fracture involves greater than 50 percent of the coronoid (image 7)

Each type can be modified: A for fractures not associated with an elbow dislocation; B for fractures associated with an elbow dislocation. The elegance of this scheme lies in its simplicity; classification can be based solely on a lateral plain radiograph. However, displacement cannot be fully appreciated on the lateral view alone, and determinations about the need for surgery require knowledge of displacement.

The O'Driscoll classification accounts for displacement in the AP plane and distinguishes among three fracture types [31]:

●Type 1 – Fracture of the coronoid tip only

●Type 2 – Fracture of the anteromedial facet

●Type 3 – Fracture through the base of the coronoid process

Indications for orthopedic consultation — All coronoid fractures associated with an elbow dislocation should be referred to orthopedic surgery. Type II and III coronoid fractures not associated with an elbow dislocation should also be referred to an orthopedic surgeon, as they can impair the mechanics of the elbow joint. Coronoid fractures that are associated with radial head fractures are likely to be unstable and require surgical intervention.

Type I fractures that are not associated with dislocation and are stable to valgus-varus stress testing may be managed by clinicians knowledgeable about fracture management without orthopedic referral. However, it should be emphasized that isolated, uncomplicated coronoid fractures are uncommon, and good outcomes depend on appropriate care (including surgical fixation when indicated) and early emphasis on regaining full joint motion. Therefore, it is reasonable to obtain orthopedic consultation for any coronoid fracture.

Initial management — Type II and III coronoid fractures without an associated elbow dislocation are managed with closed fracture reduction as necessary, splinting, and early, gentle mobilization. These patients should follow up with an orthopedic surgeon within a few days. Coronoid fractures are immobilized in a posterior, long-arm splint with the forearm in neutral position (ie, without supination or pronation).

Fractures associated with an elbow dislocation require reduction of the joint acutely, with most requiring subsequent surgical repair. Typically, comminuted fractures or those with large fragments need repair, while small fragments that are not attached to tendons can be excised.

Follow-up management — As noted above, it is reasonable to obtain orthopedic consultation for any coronoid fracture. (See 'Indications for orthopedic consultation' above.)

Isolated, uncomplicated type I coronoid fractures may be managed by non-orthopedists with experience in fracture management. The first follow-up visit is scheduled for one week after the injury, and plain radiographs are obtained to ensure that alignment is maintained and no complications have developed. The patient continues in a long-arm splint and may use a sling for comfort if necessary.

A second (and usually final) follow-up visit is scheduled at around three weeks to assess alignment and joint function. Plain radiographs are obtained. Assuming the injury is healing as expected, the splint can be discontinued, and the patient is taught how to perform gentle elbow mobility exercises. A referral to physical therapy can be made for patients who have difficulty regaining motion.

Gentle motion exercises may be introduced early, even if a splint is still in use during the day, and can be started during the first three weeks for isolated, uncomplicated coronoid fractures [32]. While direct evidence is limited, studies of other elbow injuries, such as radial neck fractures and elbow dislocations, report that early mobilization improves functional outcomes [33]. (See "Radial head and neck fractures in adults".)

Complications — The important complications from a coronoid fracture are typically due to any associated elbow dislocation and involve recurrent instability, loss of motion, and post-traumatic osteoarthritis. (See 'Elbow dislocation' below.)

Return to sport and work — Return to activity is accomplished in a stepwise fashion under the direction of the orthopedic surgeon and physical therapist.

Patients with isolated tip fractures (type I injuries) can usually return to activity as pain and motion improve over three to six weeks. The elbow is generally most uncomfortable and possibly unstable at full extension, and sometimes a hinged elbow brace that prevents the final 10 to 15 degrees of extension can be used to assist with return to sports and work.

ELBOW DISLOCATION

Mechanism and injury patterns — Elbow dislocations are the second most common major joint dislocation in adults after the shoulder. As determined by the location of the olecranon relative to the humerus, the most common dislocation is posterolateral (80 percent) or posterior (10 percent).

Elbow dislocations can be classified as simple or complex. Simple dislocations do not have an associated fracture and comprise 50 to 60 percent of injuries. Most involve ligament injuries only. Complex dislocations have an associated fracture, typically the radial head or coronoid, but the olecranon, distal humerus, or medial or lateral epicondyles may be injured as well.

More than one mechanism has been proposed [34]. Common elements include an extended elbow with the forearm in supination subjected to an axial load and a posterolateral, or valgus, force [35].

Dislocation causes a complete or near complete tear of the ligaments of the joint capsule, which provide elbow stability. In posterolateral dislocations, disruption of the ligaments occurs from lateral to medial, where the lateral collateral ligament (LCL) typically tears first, followed by the anterior capsule, posterior capsule, and medial collateral ligament (MCL) [31]. This pattern is sometimes referred to as the "Horii circle."

Direct posterior elbow dislocations result from a posterolateral force causing trauma to the coronoid process and radial head, which may fracture, and the anterior band of the MCL.

Other possible patterns of injury involving elbow dislocation include the following:

●A valgus posterolateral rotatory load may produce the "terrible triad," a dislocation associated with both a radial head or neck fracture and a coronoid fracture. The lateral ulnar collateral ligament, part of the LCL, may also tear.

●An "incomplete dislocation," known as a perched dislocation, occurs when the trochlea sits on the coronoid. In a complete dislocation, the coronoid and trochlea are completely disassociated.

●Anterior elbow dislocation is much less common than posterior. The usual cause is direct trauma to the proximal ulna while the elbow is flexed. Associated injury of the neurovascular bundle may occur.

Clinical presentation — Elbow dislocation can occur during household or work-related activities or during athletics [36,37]. Falls onto an outstretched arm and physical altercations are common causes [34]. Patients with an elbow dislocation usually present with significant pain, generalized swelling, and restricted elbow motion. Occasionally, the elbow reduces spontaneously, but significant swelling persists, and patients frequently describe the elbow as feeling unstable.

Physical examination — The patient with a posterolateral or posterior dislocation typically presents with the arm shortened and the elbow held in about 90 degrees of flexion. Observation reveals generalized elbow swelling and an obvious posterior deformity caused by protrusion of the olecranon unless the dislocation has reduced spontaneously. Palpation elicits diffuse tenderness and crepitation about the elbow. Elbow motion is severely restricted in all planes. Range of motion testing should be deferred in patients with an obvious joint deformity.

The shoulder and wrist should be examined. In the setting of an elbow dislocation, wrist instability suggests tearing of the interosseus membrane.

Complications may include injury to the brachial artery and peripheral upper extremity nerves. Therefore, neurovascular examination should include assessment of pulses, before and after reduction or manipulation, and motor and sensory nerve function:

●Ulnar nerve (figure 4) motor function can be tested by asking the patient to abduct and adduct their fingers, or make a "peace" sign (picture 2 and picture 1) [38].

●The median nerve (figure 3) and motor function of the flexor digitorum superficialis can be tested by asking the patient to make a fist. The anterior interosseus nerve, terminal branch of the median nerve, and the motor function of the flexor pollicis longus can be tested by asking the patient to make the "OK" sign (picture 3).

●The radial nerve (figure 8) and motor function of the extensor digitorum muscles can be assessed by asking the patient to extend their wrist and fingers. The posterior interosseus branch of the radial nerve can be tested by asking the patient to make the "thumbs-up" sign (picture 4).

Diagnostic imaging — Plain radiographs of the elbow, including anterior-posterior (AP) and lateral views, are obtained (image 1 and figure 5) to characterize the dislocation (eg, posterior versus anterior) and to identify associated boney injuries (image 8 and image 9). Radiographs should be obtained prior to attempts at reduction. Reduction may not be possible in patients with severely comminuted fractures or large fragments causing a mechanical block. Small, nondisplaced fractures are helpful to identify but do not affect reduction techniques.

While bedside ultrasound may be useful for assessing ligament and capsule integrity [39], ultrasound alone is not adequate for assessing a dislocated elbow. Advanced imaging, generally ordered by the orthopedic surgeon, can be performed to determine the full extent of injury.

Reduction procedure — An acutely dislocated elbow should be reduced. Standard preprocedural actions, such as obtaining informed consent, should be followed. (See "Procedural sedation in adults in the emergency department: General considerations, preparation, monitoring, and mitigating complications".)

Procedural sedation and analgesia — Unless reduction is performed soon after the joint dislocates (generally within about six hours), procedural sedation or a hematoma block is usually required. Reduction without formal procedural sedation may be attempted within this timeframe. (See "Procedural sedation in adults in the emergency department: General considerations, preparation, monitoring, and mitigating complications" and "Procedural sedation in adults in the emergency department: Medication selection, dosing, and discharge criteria".)

Use of an infraclavicular brachial plexus block for reduction of elbow dislocation has been described and is likely an effective approach where resources are available [40]. Performance of an infraclavicular block is described separately. (See "Infraclavicular brachial plexus block procedure guide".)

Analgesia for reduction of a dislocated elbow can be provided using a hematoma block. A hematoma block should not be used if there is an open fracture. A hematoma block can be performed as follows:

●Prepare equipment and draw up all necessary medications.

●Draw a triangle formed by the dislocated lateral epicondyle, radial head, and tip of the olecranon. The triangle as drawn on a nondislocated elbow is shown here (picture 5). A soft spot can be palpated in the center of the triangle – this area lies superficial to the intra-articular space, which can be visualized using ultrasound.

●Clean the skin thoroughly with antiseptic solution.

●Anesthetize the injection site. This may be done with 2 to 3 mL of 1% lidocaine, using a 22-gauge needle to create a wheal. Allow a few minutes for the skin to become anesthetized.

●Insert an 18-gauge needle attached to an empty 10cc syringe into the joint. Aspiration of blood confirms placement in the hematoma, near the dislocation site. Remove as much gross blood as possible. Ultrasound can be used to guide needle placement.

●After aspirating the blood, keep the needle in place but replace the original syringe with one containing analgesic (eg, 10 mL of bupivacaine, 10 mL of 1 or 2% lidocaine). Inject the analgesic into the joint.

Reduction techniques — Depending upon resources and clinician preference, any of the following techniques may be used to reduce a posterior elbow dislocation. There is no high-quality evidence supporting one technique over the others.

●Traction techniques – A posterior or posterolateral elbow dislocation can be reduced by a single clinician using a traction technique. The patient is positioned prone on the bed, with the dislocated elbow over the edge of the bed and the arm dangling.

The technique is performed as follows:

•With one hand, grasp the patient's wrist and stabilize it without exerting traction.

•With the opposite thumb or hand, guide the olecranon towards the fossa.

•After beginning to guide the olecranon, exert downward axial traction on the wrist.

A two-person variation allows one clinician to perform axial traction at the wrist while the other guides the olecranon into the joint. First stabilizing the wrist while centering the olecranon and then exerting traction may improve success rates.

●Leverage technique – To apply the leverage technique, the clinician places the point of their elbow at the location of the distal biceps tendon insertion at the patient’s proximal forearm, approximately in the crook of the patient’s elbow (figure 9). The patient’s forearm is supinated. The clinician then interlocks their fingers with the patient’s or grasps the patient's hand or wrist. With their other hand, the clinician braces the patient’s forearm. The clinician then flexes the patient’s elbow, using the leverage of their elbow to reduce the dislocation.

●Traction-counter traction technique – A conventional two-person traction-counter traction technique may be used for reduction. The patient can be positioned supine or seated in the bed. Next, one clinician exerts inline traction distal to the elbow while supinating the forearm, while an assistant provides countertraction proximal to the elbow. Gentle flexion of the elbow and pressure on the olecranon can be used to guide the olecranon back into place.

Post-reduction management — After reduction, the patient's arm should be guided through a gentle, passive range of motion, as inability to range the elbow smoothly suggests a possible fracture or failure to reduce the joint. Neurovascular function should be reassessed, as should the soft tissue compartments of the arm and forearm. Valgus stability should be tested as well [40]. Immediate orthopedic surgery consultation is required if there are signs suggestive of vascular compromise or acute compartment syndrome. (See 'Indications for orthopedic consultation and follow-up' below.)

Plain radiographs should be obtained to ensure adequate reduction and to assess for injury. If any abnormalities are noted, including a restriction of the joint range of motion or a neurologic deficit, the consulting orthopedic surgeon should be notified and follow-up arranged within the next three days.

Following reduction, the patient's arm can be placed in a sling or (if there is concern for a concomitant fracture) immobilized in a posterior, long-arm splint with the forearm slightly pronated and the elbow flexed to 90 degrees.

Indications for orthopedic consultation and follow-up — Emergency (ie, immediate) referral to an orthopedic surgeon is necessary if the elbow cannot be reduced or there is evidence of acute compartment syndrome. Patients with a neurologic deficit or limitations in elbow motion following reduction should be evaluated by an orthopedic surgeon within three days of injury.

All other patients should follow up with an orthopedic surgeon within two weeks to assess joint integrity. Persistent elbow instability following reduction is due either to a fracture or significant ligament injury. The orthopedic surgeon will determine the need for further imaging or intervention. For simple elbow dislocations uncomplicated by fracture or other major injury, early joint mobilization may enable the patient to regain full function sooner and reduce long-term complications [33,41,42].

Complications — The most common long-term complication is loss of elbow motion (both flexion-extension and supination-pronation can be affected), typically due to prolonged immobilization [43].

Uncommon but important complications include neurovascular injury and acute compartment syndrome, the latter of which may lead to limb ischemia, neurologic injury, and possibly loss of the limb. Heterotopic ossification, joint instability, paresthesias, and chronic regional pain have been reported [30]. (See "Acute compartment syndrome of the extremities".)

Return to sport and work — Return to activity is accomplished in a stepwise fashion under the direction of the orthopedic surgeon and the physical therapist. While a variety of factors influence the timing of returning to work or sport, on average, most patients can return to desk work in about 10 days and to heavy labor or full sport in three to six weeks.

MONTEGGIA FRACTURE IN ADULTS

Mechanism and clinical presentation — The Monteggia fracture, named for Italian surgeon Giovanni Monteggia in 1814, is a fracture of the proximal ulna associated with a dislocation of the radial head. This injury usually results from a fall onto an outstretched hand when the forearm is excessively pronated or from a direct blow onto the back of the upper forearm [44]. The injury is more common in children but may occur in adults, albeit infrequently. Monteggia fracture-dislocations in children are reviewed separately. (See "Proximal fractures of the forearm in children", section on 'Monteggia fractures'.)

In Monteggia fracture-dislocations, the ulna typically fractures distal to the coronoid, and this injury leads to disruption of the radiocapitellar and the proximal radioulnar joints. The associated radial head dislocation is easily missed in the setting of an ulnar fracture.

Patients with Monteggia injuries complain of pain in the forearm and elbow and may describe paresthesias and weakness in the hand [45].

Physical examination — Examination may reveal numbness and weakness in the hand [45]. Elbow motion is restricted. Neurovascular examination may reveal deficits in the radial (figure 8) or median (figure 3) nerve distributions, or both. Most often, the posterior interosseus nerve is injured, causing weakness of thumb and wrist extension.

Diagnostic imaging — Plain radiographs of the elbow (image 1), forearm, and wrist (image 10) are needed to assess Monteggia injuries (image 11). To ensure appropriate evaluation of the radial head in patients with an ulna fracture, a true lateral view and an oblique view of the elbow should be obtained.

On a lateral plain radiograph of the elbow, a radio-capitellar line is drawn to identify radial head dislocation [46]. A normal radio-capitellar line should run through the longitudinal axis of the proximal radius and bisect the capitellum (image 3).

If the lateral humeral line on an anterior-posterior (AP) radiograph does not intersect with the lateral cortex of the radial neck, a lateral radial head dislocation should be suspected [47]. The lateral humeral line is drawn along the lateral edge of the lateral epicondyle parallel to the axis of the distal humeral shaft. It should intersect with the cortex of the lateral radial neck.

Advanced imaging is not usually necessary in the acute setting, but computed tomography (CT) may be performed for operative planning.

Classification — The Bado classification organizes Monteggia injuries based primarily on the location of the radial head [48]:

●Type I – Radial head is dislocated anteriorly; ulna is angulated anteriorly. These comprise approximately 70 percent of Monteggia fracture-dislocations.

●Type II – Radial head is dislocated posteriorly; ulna is angulated posteriorly. These comprise approximately 5 percent of Monteggia fracture-dislocations.

●Type III – Radial head is dislocated laterally or antero-laterally; metaphyseal ulnar fracture is present. Posterior interosseous nerve may be injured. These comprise approximately 20 percent of Monteggia fracture-dislocations.

●Type IV – Radial head is dislocated anteriorly; fractures of radial head and ulnar shaft are present. These comprise 1 percent of Monteggia fracture-dislocations.

Indications for orthopedic consultation — Emergency (ie, immediate) surgical consultation is necessary for any signs of vascular compromise, nerve injury, or compartment syndrome and for all open fractures.

All acute and chronic Monteggia injuries should be referred to an orthopedic surgeon within three days of presentation, although discussion with the surgeon at the time of presentation is advised.

Management — Definitive management of an acute Monteggia fracture-dislocation is often performed in the operating room [44,49]. The ulna fracture may be treated with closed reduction, which typically results in reduction of the radial head. Should closed fracture reduction prove unsuccessful, open reduction and internal fixation are performed. Injuries to lateral ligaments are repaired as needed. Displacement of the radial head is usually associated with tear of the annular ligament. If the ligament remains intact, the radial head may slip beneath it, which is often not amenable to closed reduction, and surgical intervention is necessary [49].

Acute Monteggia fractures are defined as those that occur within one month of trauma [44,50]. If radial dislocation is diagnosed after that time, the injury pattern is considered chronic.

Management of radial head dislocation differs depending upon whether it is acute or chronic. Acute radial head dislocation as part of a Monteggia injury pattern can be managed nonoperatively after reduction, but if missed initially, surgical intervention is required in most cases, especially for injuries sustained at least three months earlier. For fracture-dislocations between one and three months old, the need for operative intervention is ill defined.

Complications — Failure to identify a radial head dislocation in patients with an ulnar shaft fracture can lead to complications resulting in significant restrictions in elbow motion. Radial head dislocation can be subtle, and thus, any "isolated" ulna fracture should be considered a Monteggia injury until dislocation is ruled out. Missed radial head dislocations lead to fibrosis in the ulnar notch, and after three weeks, closed reduction of the dislocation may be impossible [51]. Restrictions in elbow flexion result [52].

In a pediatric study of Monteggia fracture-dislocations that were missed initially, the mean angular displacement of the ulna fracture was only five degrees, reinforcing the importance of assessing all radiographs closely [53]. Other complications of the Monteggia fracture include neuropraxia of the posterior interosseous nerve, which typically resolves without intervention, and elbow stiffness, which can result from prolonged immobilization. Compartment syndrome is rare but has been reported.

Return to sport and work — Return to activity is accomplished in a stepwise fashion under the direction of the orthopedic surgeon and physical therapist.

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Fractures of the skull, face, and upper extremity in adults" and "Society guideline links: Upper extremity, thoracic, and facial fractures in children" and "Society guideline links: Muscle and tendon injuries of the upper extremity (excluding shoulder)".)

SUMMARY AND RECOMMENDATIONS

●Epidemiology – Fractures around the elbow are less common in adults than children and involve different injury patterns. Adult fractures are more commonly intra-articular and occur following a fall or during recreational activity. Elbow dislocations are the second most common dislocation in adults after the shoulder. (See 'General epidemiology' above and 'Elbow dislocation' above.)

●Radial head and neck fractures – These common elbow fractures sustained by adults are discussed in detail separately. Patients present with lateral elbow pain and a history of a fall onto an outstretched hand or direct trauma to the elbow. Examination typically reveals focal tenderness, swelling over the lateral elbow, and often decreased elbow motion. (See "Radial head and neck fractures in adults".)

●Distal humerus fractures

•Mechanism and clinical presentation – Distal humerus fractures usually result from forces driving the proximal ulna or radial head into the articular surface of the trochlea or capitellum, causing a comminuted intra-articular fracture. In young adults, this most often occurs from high-energy trauma; in older adults, from low-energy falls (eg, from standing). Examination reveals tenderness, ecchymosis, swelling that obscures the elbow's anatomic landmarks, and diminished joint motion. A patient who can perform full elbow extension is unlikely to have sustained an elbow fracture. Possible complications include injury to the distal brachial artery and median (figure 3) or ulnar (figure 4) nerves. (See 'Anatomy, mechanism, and clinical presentation' above and 'Physical examination' above and 'Complications' above.)

•Diagnostic imaging – Standard plain radiographs should be obtained, including an anterior-posterior (AP) view with the elbow flexed to 40 degrees, if possible. (See 'Diagnostic imaging' above.)

•Surgical consultation and initial management – Immediate surgical consultation is necessary for any signs of vascular compromise and for all open fractures. In addition, the orthopedic surgeon should be notified early of any associated nerve injury. Timely surgical consultation, typically within three days, should be obtained for all other distal humerus fractures. Pending consultation, distal humerus fractures can be immobilized in a posterior, long-arm splint with the forearm in neutral position. (See 'Indications for orthopedic consultation' above and 'Initial management' above and 'Return to sport and work' above.)

●Olecranon fractures

•Mechanism and clinical presentation – Olecranon fractures are usually sustained from a direct fall or blow to the elbow. Patients complain of posterior elbow pain. Palpation reveals focal tenderness. Associated dislocation of the radial head can occur; the radial head should be palpated. Triceps function can be impaired and, pain permitting, elbow extension should be assessed. The ulnar nerve should be assessed (figure 4), as it is susceptible to injury. (See 'Anatomy, mechanism, and clinical presentation' above and 'Physical examination' above.)

•Diagnostic imaging – A true lateral plain radiograph of the elbow is needed for diagnosis and to define the extent of injury, including injuries to the coronoid and radial head. (See 'Diagnostic imaging' above.)

•Surgical consultation and initial management – Immediate surgical consultation is necessary for any signs of vascular injury and for all open fractures. The surgeon should be notified of any associated nerve injury. Otherwise, orthopedic consultation should be obtained within three days for all olecranon fractures, aside from small avulsion fractures not affecting the joint. Fractures can be immobilized in a long-arm posterior splint with the forearm in neutral position; 45 rather than 90 degrees of elbow flexion may help with fracture reduction. (See 'Indications for orthopedic consultation' above and 'Initial management' above.)

●Elbow dislocations – Most dislocations are posterolateral or posterior. Dislocation can occur during household or work-related activities or during athletics. Falls onto an outstretched arm and altercations are common causes. The forearm is shortened, and the elbow held at 90 degrees of flexion. An obvious posterior deformity is present unless the dislocation has reduced spontaneously. Palpation elicits diffuse tenderness and crepitation. Elbow motion is severely restricted. Complications may include injury to the brachial artery and peripheral upper extremity nerves. (See 'Mechanism and injury patterns' above and 'Clinical presentation' above and 'Physical examination' above.)

•Diagnostic imaging – Standard plain radiographs of the elbow should be obtained prior to attempts at reduction. Reduction may not be possible with severely comminuted fractures or large fragments. (See 'Diagnostic imaging' above.)

•Reduction procedure – An infraclavicular brachial plexus block or hematoma block can be used to provide analgesia. Reduction techniques include traction, leverage (figure 9), and traction-counter traction techniques. These procedures are described in the text. (See 'Reduction procedure' above.)

•Post-reduction management – Immediate orthopedic referral is necessary if the elbow cannot be reduced or there is evidence of acute compartment syndrome. Patients with a neurologic deficit or limitations in elbow motion following reduction should be evaluated by an orthopedic surgeon within three days of injury. (See 'Indications for orthopedic consultation and follow-up' above and 'Complications' above and 'Return to sport and work' above.)

●Other elbow fractures – Additional elbow fracture types are reviewed in the text. (See 'Coronal shear fractures' above and 'Coronoid fractures' above and 'Monteggia fracture in adults' above.)