Clavicle fractures

INTRODUCTION — Clavicle fractures occur commonly, often from indirect or direct trauma to the shoulder region. Clinicians working in emergency departments and general clinics should be familiar with the common presentations and complications of this injury, as well as basic management.

This topic review will discuss the presentation and management of clavicle fractures. Other shoulder injuries and the approach to undifferentiated shoulder pain are reviewed elsewhere. (See "Acromioclavicular joint injuries ("separated" shoulder)" and "Rotator cuff tendinopathy" and "Evaluation of the adult with shoulder complaints".)

EPIDEMIOLOGY — Clavicle fractures account for approximately 2.6 percent of all fractures [1,2]. The peak incidence occurs in children and young adults. Over one-third of clavicle fractures in males occur between the ages of 13 and 20 years, while 20 percent of clavicle fractures in women occur in the same age group [3]. Incidence falls over subsequent decades before rising again in older men and women.

In a study of 1000 consecutive fractures, 69 percent occurred in the middle third of the bone, 28 percent in the distal third, and 2.8 percent in the proximal third [3]. Distal third fractures are further subdivided into three types [4]. These locations provide the basis for clavicle fracture classification. (See 'Classification' below.)

In older studies, fractures of the medial clavicle constituted only 2 to 3 percent of all clavicle fractures [1,3]. However, a subsequent study found that 9.3 percent of clavicle fractures involved the medial third [5]. The authors hypothesized that their higher rate was due to the institution's liberal use of CT (22 percent of medial clavicle fractures were seen only on CT).

CLINICAL ANATOMY — The clavicle is the first bone in the human skeleton to ossify [6]. It serves as the only bony connection between the arm and the trunk, articulating distally with the acromion (acromioclavicular joint) and proximally with the sternum (sternoclavicular joint) (picture 1). These joints are referred to as atypical synovial joints, because they are lined by fibrocartilage rather than hyaline cartilage. The clavicle is secured to the scapula by the acromioclavicular and coracoclavicular ligaments (figure 1) and is bound to the sternum by the sternoclavicular ligaments.

The clavicle is shaped like an "S". The proximal half curves outward (convex) providing space for the neurovascular bundle of the upper limb. The distal half curves back (concave) before attaching to the scapula (coracoid and acromion). Clavicle fractures usually occur at the junction (midshaft) between these two curves, most likely because this area lacks ligamentous attachments to adjacent bones and is the bone's thinnest segment.

When displacement occurs, the proximal fragment of a clavicle fracture is almost always displaced superiorly (cephalad) by the pull of the sternocleidomastoid muscle, which attaches to the proximal portion of the clavicle (image 1). The distal fragment is displaced inferiorly (caudad) by the weight of the arm (figure 2). Shortening often occurs (ie, the fractured bone ends are pulled past each other) (image 2). This is largely due to the subscapularis and pectoralis muscles, which internally rotate and pull the arm towards the chest.

Even though the clavicle is subcutaneous, with only a thin layer of overlying soft tissue, open fractures are uncommon. However, tenting (ie, taught stretching (picture 2)) of the overlying skin is relatively common. If left uncorrected, tenting may lead to necrosis of the overlying skin and conversion to an open fracture. Tenting is therefore an indication for closed reduction or surgical repair.

CLASSIFICATION — Allman classified clavicular fractures into three groups based upon location [7]:

●Group I consists of fractures of the middle third

●Group II of the distal third

●Group III of the proximal third

In a study of 1000 consecutive fractures, 69 percent occurred in the middle third of the bone, 28 percent in the distal third, and 2.8 percent in the proximal third [3]. Distal third fractures are further subdivided into three types [4]. (See 'Epidemiology' above.)

MECHANISM OF INJURY — Approximately 87 percent of clavicle fractures are caused by a fall onto the shoulder [8]. Traffic accidents and sports account for most fractures among the young [3]. Of injuries caused by traffic accidents, 39 percent occur in cyclists, 26 percent in car drivers or passengers, 17 percent in pedestrians, and 17 percent in motorcyclists [3].

Unusual causes of clavicle fractures include a direct blow from an object to the clavicle (7 percent) and indirect trauma from falls onto an outstretched hand (6 percent) [8]. There is no correlation between the mechanism of injury and the site of fracture (ie, which third is involved) [8].

FRACTURES OF THE MIDDLE THIRD (MIDSHAFT) OF THE CLAVICLE

Clinical presentation and examination — Patients with fractures of the middle third of the clavicle usually describe pain that is well localized and exacerbated by movement of the arm. They may also report a snapping or cracking sensation at the time of the injury and notice localized swelling over the affected area.

Because the clavicle lies close to the skin, examination often reveals a visible bulge due to hematoma (often with associated ecchymosis), bone angulation, or displaced bone edges. Tenting of the skin (picture 2), if present, suggests significant angulation or displacement. Typically, there is point tenderness over the fracture site. In addition, if tolerated by the patient, firm pressure on the clavicle, even if not applied directly to the fracture site, may elicit crepitus or palpable motion of the fragment.

It is important to perform a neurovascular and lung examination looking for other injuries in all patients with clavicle fractures, particularly if higher forces were involved (eg, motor vehicle collision). Additional complications that can occur with high force injuries include scapula fractures, rib fractures, hemothorax, pneumothorax, and brachial plexus injury [2]. (See "Initial evaluation and management of blunt thoracic trauma in adults".)

Diagnostic imaging — Middle third fractures are usually transverse or oblique. Displacement, shortening, and comminution (ie, the bone is broken into more than two pieces) are common (image 3).

In general, only a single anteroposterior (AP) view is required to demonstrate a middle third fracture and assess displacement. Displacement almost always occurs in the frontal plane, which is shown in an AP view (image 1). If a fracture is suspected but the AP view is unrevealing, a 45 degree cephalic tilt view can be obtained to better assess the clavicle (image 4). Nevertheless, it is difficult to measure shortening precisely using AP views [9]. When shortening is present and accurate measurement is necessary, it is best to obtain a posterior-anterior (PA) plain chest radiograph and use this to compare the lengths of the injured and uninjured clavicles. In addition to inspecting the clavicles, the clinician should look closely for associated fractures of the scapula, particularly with high force injuries.

Glenoid neck fractures, a juxta-articular type of scapula fracture, deserve a special mention. A glenoid neck fracture combined with an ipsilateral clavicle fracture produces a "floating shoulder" in which there is no stable bony continuity between the upper extremity and the trunk. This unstable injury requires urgent orthopedic evaluation [10]. Furthermore, significant angulation of a glenoid neck fracture, more than 25 degrees, may alter the normal glenohumeral joint mechanics and also requires orthopedic evaluation.

A preliminary observational study and clinical experience suggest that ultrasound can accurately diagnose some clavicle fractures at the bedside [11].

Indications for surgical referral — There are a number of indications for orthopedic referral of midshaft clavicle fractures that vary in urgency. Emergency (ie, immediate) referral is required for open fractures, neurovascular compromise, and tenting of the skin (skin stretched tautly over a displaced fracture (picture 2)). An open fracture should be suspected anytime there is a break in the skin near a fracture site. After puncturing the skin during the initial injury, fractured bone ends often retract under the skin and cannot be seen with simple inspection. A flow chart summarizing the triage and referral for midshaft clavicle fractures is provided (algorithm 1).

If respiratory compromise or hemodynamic instability exists, serious injury to intrathoracic or other structures should be suspected and immediately addressed. Such patients should be evaluated in the emergency department. (See "Initial evaluation and management of blunt thoracic trauma in adults".)

Urgent referral (eg, within a day or two) is recommended for patients with a "floating shoulder" (ie, ipsilateral clavicle and glenoid neck fractures). Although various treatments are used for floating shoulder, operative repair appears to be superior in most cases [12,13]. The radiographic findings in midshaft fractures are discussed in the preceding section.

Other indications for orthopedic referral include complete fracture displacement, comminution, and shortening. Although the angulation of some clavicle fractures can be impressive, the degree of angulation alone is not a decisive factor for orthopedic referral. Instead, the clinician should assess the patient closely for the referral indications described here.

A completely displaced clavicle fracture is defined by the presence of displacement greater than one bone width. In the past, nonoperative treatment was recommended even if displacement was considerable. However, completely displaced fractures treated nonoperatively produce unsatisfactory results in over 30 percent of patients, with nonunion rates higher than previously thought (7 to 15 percent) and worse cosmetic results (image 1 and image 2) [14-19]. Thus, we suggest orthopedic referral for completely displaced fractures, especially if comminution (image 3) or shortening (image 2) are present. Comminution confers a higher risk of nonunion and other long-term sequelae [20]. Shortening greater than 18 mm in males and 14 mm in females confers a significant risk of morbidity, including local tenderness, numbness, pain when lying on the affected side, impaired range of motion, impaired strength, and cosmetic abnormalities [21].

Depending upon the clinical scenario (eg, degree of fracture displacement and other fracture characteristics), patient needs (eg, occupational, recreational), and patient preferences (eg, assessment of the risks and benefits with surgery versus conservative care), the patient and surgeon may decide that either operative repair or nonoperative management is the best approach. This decision should be made after the patient and surgeon have thoroughly discussed all pertinent issues. In some cases, it may be reasonable to treat nonoperatively initially and then proceed to surgical repair if results are unsatisfactory after six months [22].

Orthopedic referral may be helpful for less severely displaced fractures if the patient is active or athletic or is concerned about the appearance of a visible lump at the fracture site. It is best to discuss referral with the patient in such cases. Patients with a symptomatic malunion or a nonunion (image 5) after 12 to 16 weeks should be referred. No additional treatment is needed if a patient with malunion or nonunion is asymptomatic.

Surgery for displaced fractures — Evidence in support of surgical management of displaced, middle third clavicle fractures is growing. While prior evidence was limited by the quality of some studies and differences in inclusion criteria, the findings of subsequent, larger meta-analyses suggest advantages to surgical management for many middle third clavicle injuries [19,23,24]:

●A 2019 meta-analysis of 14 randomized trials involving 1546 patients with displaced, middle third clavicle fractures reported that only 10 of 705 patients (1.4 percent) in the surgical treatment group developed nonunion (primary outcome) compared with 110 of 667 patients (16.5 percent) treated nonoperatively [24]. A small subset of studies reported that functional outcome scores (DASH and Constant) were better in the surgery group. Aside from some aspects of blinding, the studies were generally of adequate to good quality. These results suggest a more favorable outcome with surgery.

●A meta-analysis of fourteen controlled trials involving 1469 adults with displaced, middle third clavicle fractures emphasized the limited quality of the studies ("almost all trials had design features that carry a high risk of bias"), and reported that patients treated surgically did not appear to have statistically or clinically significant improvements in pain or shoulder function at one year of follow-up compared with those managed conservatively [19]. However, the authors concluded that surgical repair may reduce the need for additional nonroutine surgery to treat nonunion, malunion, and other complications (risk ratio [RR] 0.32, 95% CI 0.20-0.50).

●A 2015 meta-analysis of 15 randomized trials found no clinically significant difference in outcome among surgically versus conservatively treated patients with middle third clavicle fractures, with similar complication rates and similar needs for additional surgery [23]. Modest functional improvements were noted at one year in the operative group, but these differences were not clinically important. While secondary surgery rates were similar in both groups, the authors note that secondary surgery for complications following non-operative management (eg, non-union) are typically more complex and accompanied by higher complication rates. In addition, secondary surgery is often performed greater than 12 months after the initial injury, beyond the follow-up period for many studies. The authors reiterated concerns about possible bias in the included studies.

●A limitation of some studies is the duration of follow-up. A 2022 meta-analysis of 31 studies involving 3029 patients focused on outcomes at different time points [25]. Consistent with some prior reviews, this meta-analysis reported greater functional improvements in patients treated surgically but found that surgery conferred even greater functional advantages when these were assessed after 24 months. While the difference in validated functional score was statistically significant, it did not meet the established threshold for clinical significance.

Initial nonoperative treatment — Conservative treatment produces good results with nondisplaced middle third clavicle fractures [20,26]. Provided there are no indications for referral, we recommend the approach described below for patients with nondisplaced fractures and for those with displaced fractures who are poor operative candidates or prefer to avoid surgery. Even if displacement is present, most patients have good outcomes with conservative treatment [14].

The goal of treatment for middle third fractures is pain control and reduction of motion at the fracture site until clinical union occurs. Icing intermittently during the first 48 to 72 hours helps control both pain and swelling. We recommend applying ice packs for 20 to 30 minutes every one to three hours while awake.

Adequate pain control is generally achieved with moderate strength opioids initially (eg, hydrocodone or oxycodone) and acetaminophen alone after three to seven days. The use of nonsteroidal antiinflammatory drugs in fractures is discussed separately. (See "Overview of COX-2 selective NSAIDs", section on 'Possible effect on fracture healing'.)

The fracture site is best stabilized by restricting shoulder motion to less than 30 degrees of abduction, forward flexion, or extension. Either a sling or a figure of eight bandage (picture 3) can be used. While evidence is limited, outcomes appear to be similar, although each approach has advantages and disadvantages [27,28]:

●A sling is more comfortable and in small randomized trials has produced greater patient satisfaction than a figure of eight bandage [27,29]. However, the sling limits use of the affected arm and may cause the elbow to stiffen if the patient does not conscientiously perform range of motion exercises.

●In contrast to the sling, the figure of eight bandage leaves the elbow and hand free for daily activities, avoids elbow stiffness, and has the potential to correct fracture shortening. However, the figure of eight bandage has a number of potential limitations:

•It must be adjusted frequently to keep it tight and maintain the shoulders in a "position of attention". Patients often find this uncomfortable.

•Tightening of the figure of eight bandage is performed from behind and requires assistance. Hence, it is not a good choice for the patient who lives alone.

•Excessive tightening of the bandage increases the risk for skin breakdown, upper extremity edema, and brachial plexus palsy.

•It may not provide enough support during early treatment, which is easily addressed by temporarily adding a sling.

For middle third fractures that are nondisplaced or have less than complete displacement, we suggest treatment with a sling and daily elbow range of motion exercises several times per day to maintain full flexion and extension. Range of motion exercises, which should be started no later than three to five days after injury, are performed with the arm removed from the sling and the elbow maximally extended and maximally flexed several times. The forearm should be pronated and supinated several times as well.

For patients with complete displacement who decline surgery, we suggest treatment with a figure of eight bandage, which may help to correct or prevent shortening. despite limited evidence to support its use.

Follow-up care — For patients with nondisplaced or otherwise uncomplicated middle third clavicle fractures managed non-operatively, immobilization with either a sling or figure of eight bandage is continued until clinical union occurs (ie, the fracture site is nontender and the patient can move the arm fully with little or no discomfort). Follow-up visits begin one to two weeks after injury to assess clinical symptoms, and every two to three weeks thereafter until the patient is asymptomatic and shoulder function is satisfactory. While the shoulder is immobilized, the arm can be used as symptoms allow, but strenuous activities should be avoided. Patients treated with a sling are encouraged to perform elbow range of motion exercises to maintain normal function and prevent stiffness.

Clinical union usually occurs by 6 to 12 weeks in adults and 3 to 6 weeks in children. Radiographs are usually obtained at this point, although callus may not appear for several more weeks. If clinical union has occurred, immobilization can be discontinued even if callus is not seen. Radiographs can be repeated four to six weeks later if there is a need to document radiographic union (image 6).

After immobilization is discontinued, patients should be advised to perform shoulder range of motion and strengthening exercises to hasten recovery. Supervision by physical therapists facilitates this process, particularly early on.

Patients should be informed that callus formation during healing may produce a prominent lump at the fracture site. In children, the callus usually remodels and disappears. This occurs to a lesser extent in adults, and most will have a persistent, visible lump.

Complications — Serious complications are uncommon after middle third clavicle fractures. Neurovascular complications at presentation or after reduction are rare and include subclavian artery or vein compression, thoracic outlet syndrome, and brachial plexus injury. (See "Brachial plexus syndromes".)

Malunion is the most common complication and may result in angulation, shortening, or a poor cosmetic result. Even with malunion, patients often have acceptable function. Some malunions may cause functional or neurologic problems, particularly if there is shortening greater than 2 cm [30]. Delayed operative correction of the shortening improves symptoms in selected patients [30].

Nonunion occurs when the fracture fails to heal after four to six months. Predisposing factors include greater initial displacement, severe trauma, comminution, shortening, primary open reduction, older age, and inadequate immobilization [16,31]. A late complication occasionally associated with nonunion is brachial plexus compression neuropathy resulting from hypertrophic callus formation.

Pediatric considerations — Among children, 90 percent of clavicle fractures occur in the middle third [1]. In children 10 and under, 60 percent of clavicle fractures are nondisplaced. Above age 10, the majority are displaced (as in adults) [1].

Treatment of nondisplaced fractures does not differ from adults. Healing occurs more quickly, and immobilization is generally necessary for only three to four weeks. Contact sports and hard blows to the shoulder should be avoided for an additional two to three weeks. Bowing of the clavicle (bending of the bone without overt disruption of the cortex) may occur in young children. This injury should be treated like other clavicle fractures to prevent progression to an overt fracture.

Little data exists to guide the choice between surgery and nonoperative care for displaced clavicle fractures in children and young adolescents. Retrospective, observational studies suggest surgery may be less beneficial than for adults, as bony remodeling is robust in children [32-35]. This highlights the importance of shared decision-making with the patient and family when determining treatment.

Clavicle fractures reportedly comprise 95 percent of fractures during childbirth [36]. In the newborn, such fractures are more commonly associated with difficult deliveries, such as shoulder dystocia or breech. (See "Shoulder dystocia: Intrapartum diagnosis, management, and outcome".)

FRACTURES OF THE DISTAL THIRD OF THE CLAVICLE

Clinical presentation and examination — Fractures of the distal clavicle are easily confused with acromioclavicular (AC) separations. Both present with pain and tenderness around the AC joint, often with swelling and ecchymosis. The cross arm test (adduction of the arm across the chest) increases pain in both conditions. Little or no deformity is seen on examination, unless a type II fracture is present (image 7).

The types of distal clavicular fractures are described in the next section. The location of maximal tenderness may provide a clue to the diagnosis. With fractures, maximal tenderness is usually located medial to the AC joint, instead of directly over the joint. Nevertheless, radiography is necessary to differentiate between the two injuries.

Diagnostic imaging — Distal third clavicle fractures are divided into three types based upon fracture site and ligamentous stability (figure 3 and figure 4 and figure 5 and figure 6).

Type I fractures are most common. In this injury, intact ligaments hold the proximal and distal fragments in alignment and no displacement occurs (image 8).

In type II fractures, the proximal (medial) fragment loses its ligamentous attachment and is displaced superiorly (cephalad) (image 7). This may occur in two ways: type IIA in which the coracoclavicular ligament is not torn but inserts only on the distal fragment, and type IIB in which the coracoclavicular ligament is torn.

Type II fractures are difficult to diagnose on standard radiographs. Oblique views (45 degrees anterior and posterior) or stress views of both shoulders (10 pound weight strapped to each wrist to exaggerate displacement) are often needed to demonstrate displacement.

Type III fractures are intraarticular, extending into the AC joint (figure 6). Type III injuries are easily overlooked, as the fracture line may be subtle and intact ligaments generally prevent displacement.

Indications for orthopedic referral — We recommend orthopedic referral for all type II distal clavicle fractures because they are prone to complications and treatment remains controversial. Operative repair is recommended by some authors, and a wide range of surgical approaches has been used [37-41]. Others report that although nonunion and delayed union are common (approximately 30 percent), conservative therapy generally provides a good functional outcome and avoids the high complication rates associated with surgery [42-44]. A 2021 meta-analysis of 59 articles (2284 patients) confirmed generally good functional outcomes and high nonunion rates (31 percent) with conservative treatment, but only 59 of the 2284 patients were treated nonoperatively [45].

Referral is reasonable for patients with type III distal clavicle fractures. These fractures extend into the AC joint and are theoretically prone to future degenerative change, which may limit shoulder function. Patients who choose nonoperative management should be made aware of these potential risks.

Little data is available about outcomes for type III fractures and findings are contradictory. One observational study found a high rate of subsequent AC joint arthrosis [4]. In a later observational study with 15 years of follow-up, only 1 of 14 patients had pain and mobility was no different than patients with other distal clavicle fractures [46]. In the event of future problems, both patient and clinician may be more content knowing that specialty care was provided, or at least offered. If the patient declines referral, conservative care can be provided as described below.

Initial treatment — Type I and type III distal clavicle fractures are usually minimally displaced and heal well with conservative therapy. Immobilization in a sling provides comfort.

Conservative treatment of type II fractures involves supporting the weight of the arm to keep the edge of the proximal fragment as close as possible to the coracoid process. The goal is to foster healing in an anatomic position and this can be achieved with a sling [43]. A figure of eight bandage should NOT be used for type II fractures, as it does not support the weight of the arm and may increase displacement [2].

Early movement of the glenohumeral joint is encouraged, beginning as soon as symptoms permit, to prevent development of a frozen shoulder [43]. Range of motion exercises can begin with the arm in a sling. Pendulum exercises are useful initially. To perform them, the patient bends forward at the waist, dangles the arm in the sling and gently makes circles with the arm.

Follow-up care — Follow-up appointments are needed every two to three weeks until symptoms resolve and satisfactory shoulder function is achieved. Immobilization with a sling is continued until clinical healing has occurred (resolution of pain and tenderness). This usually requires three to six weeks. Once the patient regains full and painless shoulder range of motion, strengthening exercises are begun [43].

Complications — Overall, nonunion occurs more frequently in fractures involving the distal third of the clavicle compared to other locations, with reported rates ranging from 28 to 44 percent. However, many such non-unions remain asymptomatic and require no further treatment [47]. Nonunion is uncommon with nondisplaced distal clavicle fractures (ie, types I and III) [40]. However, nonunion is common with type II fractures (22 to 33 percent), as is delayed union (45 to 67 percent require over three months to heal) [40].

A possible late complication of intraarticular (type III) fractures is degenerative change within the AC joint. In such cases, plain films usually demonstrate osteophytes, narrowing of the joint space, or resorption of the distal clavicle. Initially, symptoms should be managed with conservative therapy, such as a short course of oral nonsteroidal medication or a local steroid injection. If several attempts at conservative management fail to control symptoms or function is compromised, resection of the distal clavicle may be necessary.

Pediatric considerations — In children with type II fractures, the periosteal sleeve generally remains intact. This prevents displacement and makes type II fractures in children more stable than in adults. Any nondisplaced distal clavicle fracture in a child (type I, II, or III) can be managed with sling immobilization for comfort and early range-of-motion exercises as soon as pain permits. Healing usually occurs in four to six weeks. Displaced fractures should be referred.

FRACTURES OF THE PROXIMAL THIRD OF THE CLAVICLE

Clinical presentation and examination — Both acute fractures and stress fractures may occur in the proximal (or medial) third of the clavicle. Although least common among the different clavicle fracture types, acute proximal fractures are most often associated with serious injury: 84 percent are caused by vehicular trauma, 90 percent involve multisystem trauma, and 20 percent of patients die within one month of their injuries [5]. Deaths are not due to injuries directly caused by the clavicle fracture but rather by associated chest, head, neck and visceral trauma [5]. Patients with major trauma should be thoroughly evaluated in the emergency department. (See "Initial evaluation and management of blunt thoracic trauma in adults".)

Stress fractures develop insidiously from repetitive stress on the proximal clavicle related to a range of activities, including: rowing [48], gymnastics [49], cable-making [50], and even nervous tics [51]. In patients with persistent pain in the sternoclavicular area and no history of acute trauma, particularly those who engage in repetitive activities involving clavicle motion, a stress fracture may be the cause. Evaluation generally begins with plain radiographs, followed by CT if necessary. Additional studies are occasionally needed to exclude other causes of bone pain. (See "Overview of stress fractures".)

Both acute and stress fractures of the proximal clavicle usually present with pain near the sternoclavicular area, worsened by movement of the shoulder. The supine position may increase pain, and patients are usually more comfortable if they sit up and support the arm, although trauma patients are not permitted to do so until cervical injury is ruled out [2].

In acute fractures, ecchymosis may be noted, especially if significant ligamentous injury and displacement of fracture fragments has occurred. An anteriorly (or outwardly) protruding medial clavicle suggests an anterior sternoclavicular dislocation but may be caused by a medial fracture (sometimes called a "pseudo-dislocation" of the sternoclavicular joint) [52]. When the medial clavicle is displaced posteriorly (or inwardly), it is often difficult to palpate. This finding suggests a posterior sternoclavicular dislocation. However, in young patients, it may represent a physeal fracture [53].

It is important to perform a neurovascular and lung examination looking for other injuries in all patients with clavicle fractures, particularly if higher forces were involved (eg, motor vehicle collision). Additional complications that can occur with high force injuries include scapula fractures, rib fractures, hemothorax, pneumothorax, and brachial plexus injury [2]. (See "Initial evaluation and management of blunt thoracic trauma in adults".)

Diagnostic imaging — Proximal clavicle fractures may occasionally be missed on standard AP radiographs due to overlying bony shadows. Radiographs of each shoulder using a 45 degree cephalic tilt view and careful comparisons of the injured and uninjured sides may reveal the injury (image 4) [2]. Proximal fractures are also difficult to see on radiographs if the costoclavicular ligaments remain attached to the outer fragment, as displacement is minimal [54].

If plain radiographs appear normal or are inconclusive but clinical suspicion for a fracture remains, computed tomography (CT) should be performed to exclude a fracture and investigate possible intrathoracic injury. CT and magnetic resonance imaging (MRI) enable clinicians to distinguish fractures from other injuries and to assess the patient for other serious injuries [5,53,54]. One case series found that no acute medial clavicle fractures were missed by CT scan, while 22 percent were missed on plain radiographs [5]. In patients at low risk of injury, further imaging is generally not necessary.

Clinical and radiographic evidence of swelling in the proximal clavicle may falsely suggest a neoplastic or inflammatory process. Further imaging may be necessary to rule out such pathology [51].

Indications for referral — All patients with acute proximal third clavicle fractures should be carefully evaluated in the emergency department for associated head, neck, chest, and visceral injuries. The incidence of serious associated injuries is approximately 90 percent. Emergent surgical repair is necessary for open clavicle fractures and for any significant intrathoracic or neurovascular injury from posterior displacement of fracture fragments [2]. Patients with significant displacement of a fracture fragment (greater than one centimeter), posterior displacement, or posterior sternoclavicular dislocation should be urgently referred to an orthopedist after other injuries have been excluded. (See "Initial evaluation and management of chest wall trauma in adults", section on 'Sternoclavicular dislocation'.)

Initial treatment — Initial management of nondisplaced proximal clavicle fractures, such as stress fractures, is nonoperative and involves ice, analgesics, and a sling for support [55]. Use of the arm is allowed as symptoms permit [2]. All other injuries are managed by the orthopedic surgeon.

Follow-up care — Most uncomplicated, acute proximal clavicle fractures are successfully managed with immobilization in a sling. Healing generally occurs within six to eight weeks. Definitive management is similar to that for type I and III distal clavicle fractures [2].

Clinicians describe the successful treatment of medial clavicle stress fractures with cessation of the inciting activity for several weeks followed by physical therapy to improve posture, scapulothoracic mechanics, and rotator cuff strength [48,49]. This is followed by a gradual, progressive return to sport. Return to full training and competition may require two months or longer following diagnosis.

Complications — Nonunion and posttraumatic arthritis are the most frequent complications of proximal clavicle fractures [2]. Inward sternoclavicular dislocations or inwardly displaced fracture fragments may cause severe injuries, including pneumothorax, subclavian vessel laceration, and brachial plexus compression [6].

In the largest published series of medial third fractures, 32 patients were followed for an average of 15 months. Forty-seven percent of patients had no pain, but 25 percent had mild ongoing pain, 22 percent had moderate pain, and 6 percent had severe pain at follow-up [5]. This is somewhat higher than with most fractures, perhaps related to the severe trauma that usually causes these fractures.

Pediatric considerations — As with adults, children rarely sustain proximal clavicle fractures. When present, these fractures usually involve the physis near the sternoclavicular (SC) joint; true SC dislocations generally do not occur in children [6,54]. The physis adjacent to the SC joint is the last in the body to close; fusion to the clavicle shaft occurs at 23 to 25 years [6].

As in adults, initial evaluation is performed with plain radiographs. A CT scan can help delineate injuries to the region of the proximal clavicle in patients with severe injuries [6]. Medial clavicle physeal injuries sometimes produce only minimal symptoms without deformity and may not be identified until a healing callus becomes visible radiographically at the fracture site [2].

Pediatric patients with nondisplaced medial clavicle fractures may be placed in a sling for comfort and instructed to begin range of motion exercises as pain allows. Anteriorly displaced fractures can generally be treated without reduction because the displacement is usually well tolerated and in most cases the bone remodels [2]. Fractures with posterior displacement should be referred and may be treated with open reduction [53]. This is done urgently if any sign of neurovascular compromise exists.

As in adults with medial clavicle fractures, it is important to maintain a high index of suspicion for other injuries. The patient should be evaluated in an emergency department if significant trauma was involved or if symptoms or clinical findings suggest a serious concurrent injury.

RETURN TO WORK OR SPORT — The return to work or sport is individualized based upon patient age, fracture location and severity, the degree of clinical and radiological healing, and the work or sport activity in question [31]. Most patients return to preinjury levels of activity within six to eight weeks.

In general, patients with distal third fractures return to preinjury levels of activity sooner than those with middle third fractures, sometimes as soon as four to six weeks. Patients should avoid contact sports and strenuous activities until four weeks after clinical healing to allow sufficient healing at the fracture site.

Generally speaking, athletes should not return to sport until they have full range of motion, normal strength of the shoulder, and no pain with forceful palpation over the fracture site [31]. Those involved in noncontact sports can generally return to play by six weeks while those involved in contact sports require 8 to 12 weeks [56].

For contact sport athletes who have had operative management, some experts recommend removing hardware before return to play [57]. Hardware is typically removed one year after placement. To reduce the risk of refracture, patients should allow approximately six to eight weeks after removal for the screw holes to fill with bone before returning to play [31].

ADDITIONAL INFORMATION — Several UpToDate topics provide additional information about fractures, including the physiology of fracture healing, how to describe radiographs of fractures to consultants, acute and definitive fracture care (including how to make a cast), and the complications associated with fractures. These topics can be accessed using the links below:

●(See "General principles of fracture management: Bone healing and fracture description".)

●(See "General principles of fracture management: Fracture patterns and description in children".)

●(See "General principles of acute fracture management".)

●(See "General principles of definitive fracture management".)

●(See "General principles of fracture management: Early and late complications".)

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: Acute pain management".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topics (see "Patient education: Fractures (The Basics)" and "Patient education: Clavicle fracture (The Basics)")

SUMMARY AND RECOMMENDATIONS

●Classification, epidemiology, and mechanism – Clavicle fractures are categorized by location. Approximately 69 percent occur in the middle third, 28 percent in the distal third, and 3 percent in the proximal third. Acute fractures of the proximal third of the clavicle often stem from high energy trauma and are associated with severe internal injury. Most clavicle fractures are caused by a fall onto the shoulder; traffic accidents and sports account for most fractures among the young. (See 'Epidemiology' above and 'Classification' above and 'Mechanism of injury' above.)

●Clinical presentation and physical examination – It is important to assess vital signs and to perform a neurovascular and lung examination in all patients with clavicle fractures, particularly if the cause involved higher energy forces (eg, motor vehicle collision). Patients involved in high energy trauma or with symptoms (eg, dyspnea) or clinical findings suggestive of internal injury should be assessed in the emergency department. As the clavicle lies close to the skin, examination often reveals a visible bulge due to hematoma (often with associated ecchymosis), bone angulation, or displaced bone edges. (See 'Clinical presentation and examination' above.)

●Diagnostic imaging – In general, a single anteroposterior radiograph is sufficient for assessment; however, a PA chest view allowing comparison of clavicle length between the injured and uninjured clavicles may be helpful when a precise measurement of shortening is clinically relevant. Middle third clavicle fractures are often associated with displacement, shortening, and comminution. (See 'Diagnostic imaging' above.)

●Indications for surgical referral – Immediate orthopedic referral is required for clavicle fractures associated with signs of neurovascular compromise, open wounds, or skin tenting (picture 2). Fractures associated with respiratory compromise or hemodynamic instability suggest concomitant injury to intrathoracic structures. Such patients should be evaluated immediately in the emergency department. Urgent referral (within a day or two) is needed for patients with ipsilateral clavicle and glenoid neck fractures ("floating shoulder"). (See 'Indications for surgical referral' above.)

●Management of middle third clavicle fractures – Operative versus nonoperative treatment of middle third clavicle fractures is individualized and based on fracture characteristics, such as the degree of displacement, as well as functional and cosmetic concerns. We suggest referral to an orthopedic surgeon for middle third clavicle fractures with complete displacement (image 1), shortening (image 2), or comminution (image 3). A flow chart summarizing the triage and referral for midshaft clavicle fractures is provided (algorithm 1).

Evidence supporting surgical management of such fractures, based primarily on the higher rates of nonunion in those managed nonoperatively, is growing. (See 'Indications for surgical referral' above.)

Patients with nondisplaced or minimally displaced, and otherwise uncomplicated, middle third fractures are treated with a sling, analgesics, and elbow range of motion exercises. For patients with complete displacement who decline surgery, immobilization using a figure of eight bandage may help to correct or prevent shortening, but a sling is acceptable. (See 'Initial nonoperative treatment' above and 'Follow-up care' above.)

●Management of distal clavicle fractures – Clinically, fractures of the distal clavicle are easily confused with acromioclavicular separations. Radiographs are necessary to differentiate between the two. Orthopedic referral is recommended for most distal clavicle fractures. An exception is type I fractures confirmed by normal stress views using plain radiographs. Confirmed type I fractures can be managed using a sling and early shoulder range of motion exercises, begun as soon as symptoms allow. (See 'Fractures of the distal third of the clavicle' above.)

●Management of proximal and stress clavicle fractures – Acute fractures of the proximal clavicle should alert the physician to the possibility of serious internal injury. In most cases, evaluation is performed in the emergency department. If there are no associated injuries and the fracture is nondisplaced, treatment involves sling immobilization. Stress fractures develop insidiously from repetitive stress on the proximal clavicle related to a range of activities, including rowing and gymnastics. Conservative treatment is generally successful. (See 'Fractures of the proximal third of the clavicle' above.)

●Pediatric considerations – Among children, 90 percent of clavicle fractures occur in the middle third. In children 10 and under, the majority are nondisplaced; above age 10, the majority are displaced. Treatment generally does not differ from that recommended for adults, but healing occurs more quickly. Special pediatric considerations for each type of clavicle fracture are described in the text.