Download Chapter 268_Shoulder and Humerus

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Tintinalli's Emergency Medicine: A
Comprehensive Study Guide >
Shoulder and
Humerus Injuries
John P. Rudzinski; Laura M. Pittman; Dennis T. Uehara
Sternoclavicular Sprains and Dislocations
The sternoclavicular joint is the most frequently moved, nonaxial joint of the body. It also has the least amount of
bony stability of any major joint because less than half of the medial end of the clavicle articulates with the upper
sternum. Therefore, joint stability depends on the integrity of the surrounding ligaments, which give the
sternoclavicular joint surprising strength. As a result, the majority of injuries to this area are simple sprains, and
dislocations and fractures are uncommon.
Forcing the shoulder forward suddenly, or applying a medially directed force to the shoulder, may result in a sprain
to the sternoclavicular joint. Pain and swelling are localized to the joint, and treatment is symptomatic with ice,
sling, and analgesics. Differential diagnosis in the nontrauma patient should include consideration of septic
arthritis, especially in injection drug users.
Dislocations are unusual and typically result from motor vehicle crashes or sports injuries. If the shoulder is rolled
forward at the time of impact, a posterior dislocation may result from a direct blow or from an indirect force to the
shoulder. An anterior sternoclavicular joint dislocation may result from the same indirect force if the shoulder is
rolled backward at the moment of impact. Posterior sternoclavicular joint dislocations are much less common than
anterior dislocations.
Patients with a sternoclavicular joint dislocation have severe pain that is exacerbated by arm motion and lying
supine. The shoulder appears shortened and rolled forward. On examination, anterior dislocations have a
prominent medial clavicle end that is visible and palpable anterior to the sternum, although swelling and
tenderness may impede diagnosis. In posterior dislocations, the medial clavicle end is less visible and often not
palpable (Figure 268-1), and the patient may have signs and symptoms of impingement of the superior mediastinal
contents.
FIGURE 268-1.
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Right posterior dislocation shows less visible right medial clavicle. (Courtesy of John Rudzinski, MD.)
Routine radiographs may not be diagnostic. Special views and comparison with the other clavicle may be helpful.
CT is the imaging procedure of choice (Figures 268-2 and 268-3), and IV contrast may be administered to further
delineate injury to adjacent mediastinal structures (Figure 268-4).
FIGURE 268-2.
Clavicle radiograph shows asymmetry of the clavicles. Arrow indicates asymmetric and inferiorly displaced medial
clavicle. (Courtesy of Rockford Health System.)
FIGURE 268-3.
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CT scan shows right posterior sternoclavicular dislocation. Arrow indicates disrupted sternoclavicular joint with
posterior displacement of clavicle and compression of adjacent lung. (Courtesy of Rockford Health System.)
FIGURE 268-4.
Sternoclavicular joints. The relationship of the sternoclavicular joint to adjacent structures.
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Treatment
Anterior Sternoclavicular Dislocations
Patients with uncomplicated anterior dislocations may be discharged without an attempted reduction, as
this injury has little or no impact upon function. For closed reduction, the patient is placed supine with a towel
roll or similar between the scapulae. The arm is abducted to 90 degrees, traction is applied with slight extension by
moving the arm toward the ground, and pressure is placed over the medial end of the clavicle.1 Even with
reduction, the joint is usually unstable and re-dislocates when pressure is released. Clavicular splinting, ice,
analgesics, and orthopedic referral are required.
Posterior Sternoclavicular Dislocations
Posterior dislocations may be associated with life-threatening injuries to adjacent structures, including
pneumothorax or compression or laceration of surrounding great vessels, trachea, or esophagus.
Orthopedic consultation is necessary for closed reduction, which ideally should be performed in the operating
room with trauma or vascular surgery available.1 Open reduction may be necessary. For closed reduction, patient
positioning is the same as for anterior reduction. The medial clavicle is manually grasped, or a towel clamp is
applied to the medial clavicle and then pulled upward, to relocate the sternoclavicular joint.
Special Population: Children
The medial clavicular epiphysis is the last epiphysis of the body to appear radiographically (age 18 years old) and
the last to close (age 22 to 25 years old). An apparent sternoclavicular joint dislocation in children and young adults
is typically a Salter-Harris type I or II fracture, with either anterior or posterior displacement of the clavicular
metaphysis.2 Orthopedic consultation is recommended because some patients will require reduction while others
will achieve adequate results with fracture healing and remodeling.
Clavicle Fractures
The clavicle provides support and mobility for upper extremity tasks by functioning as a strut that connects the
shoulder girdle to the trunk. In addition, the clavicle protects the adjacent lung, brachial plexus, and subclavian and
brachial blood vessels. The most common mechanism of injury is a direct blow to the shoulder. Transmission of
the compressive force results in a buckling of the clavicle, which fractures once a critical force is achieved. Eighty
percent of clavicle fractures involve the middle third, 15% the distal third, and 5% the medial third. Open fractures
can result from extreme tenting and piercing of the overlying skin. Although the vast majority of clavicular fractures
have a benign course, serious associated injuries and complications may occur. Trauma may result in associated
injuries to the adjacent lung and neurovascular structures. Children will often have a greenstick fracture or a
bowing deformity without a definite fracture.
Patients typically present with swelling, deformity, and tenderness overlying the clavicle. The arm is slumped
inward and downward and is supported by the other extremity. Routine clavicle radiographs may miss some
fractures, particularly at either end of the bone, due to overlap of surrounding structures. Definitive diagnosis may
require CT.
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Emergent orthopedic consultation will be necessary for open fractures, fractures with neurovascular injuries, and
fractures with persistent skin tenting. Severely comminuted or displaced fractures may require operative
intervention and urgent referral (Table 268-1).3,4 Similarly, distal clavicle fractures with displacement are often
associated with rupture of the coracoclavicular ligament, and may require operative intervention to avoid
nonunion. Medial clavicle injuries can be associated with intrathoracic injures and develop late complications
such as arthritis.5
Table 268-1 Middle Clavicle Fracture Nonunion Risk Factors
Initial shortening >2 cm
Comminuted fracture
Displaced fracture
Significant trauma
Female
Elderly
Numerous forms of treatment have been described, with immobilization using a sling and analgesics usually being
successful for non- or minimally displaced medial clavicle fractures. Healing may occur as rapidly as 2 weeks for
infants, with most adults healing over a 4- to 6-week period. The nonunion rate varies from 0.1% to 15.0%.
Scapula
Scapula Fractures
The scapula links the axial skeleton to the upper extremity and serves as a stabilizing platform for motion of the
arm. Fractures are infrequent, and most occur in young adult men. The mechanism of injury usually is from a direct
blow, direct trauma to the shoulder area, or from a fall on an outstretched hand. The indirect axial load transmitted
by a fall on an outstretched arm may result in a scapular neck fracture or a fracture of the glenoid through a
shoulder dislocation. Scapular fractures are classified by their anatomic location (Figure 268-5), with fractures of
the body and glenoid neck being most common.
FIGURE 268-5.
Sites of scapula fractures. A. Body. B. Glenoid rim. C. Intra-articular glenoid. D. Neck. E. Acromion. F. Spine. G.
Coracoid.
Patients with isolated scapular fractures typically will present with localized tenderness over the scapula and the
ipsilateral arm held in adduction. Any arm movement will exacerbate pain. Due to the high energy typically
required to fracture this protected bone, there is a high association (>75%) of injuries to the ipsilateral lung,
thoracic cage, and shoulder girdle, with fractures of the ribs most common.6 Carefully investigate for
associated thoracic injuries.
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Overlying structures may obscure a scapular fracture on a single trauma anteroposterior (AP) chest radiograph. A
dedicated scapular series, including AP, lateral, and axillary scapular views, will identify most fractures. Os
acromiale, present in up to 15% of the population, may be easily confused with a mid-acromion fracture on a
lateral axillary view; rounded edges and bilaterality may assist in differentiation from a fracture.7 However, scapula
fractures are often associated with other significant injuries, and, hence, diagnosis may be delayed or initially
missed entirely. CT scan of the chest will identify both scapular and associated pathology, and a dedicated CT of
the scapula can also be obtained.
The vast majority of scapular fractures are treated nonsurgically, with sling, ice, analgesics, and early range-ofmotion exercises. Surgical intervention may be necessary for significant or displaced articular fractures of the
glenoid, angulated glenoid neck fractures, acromial fractures associated with a rotator cuff tear, and some
coracoid fractures.
Disability is more likely to be associated with fractures of the glenoid, acromion, or coracoid. However,
complications are uncommon, and healing with some degree of malunion does not typically result in significant
disability.
Scapulothoracic Dissociation
Traumatic scapulothoracic dissociation results from severe trauma, such as high-speed motor vehicle crashes and
life-threatening falls. A sudden severe traction to the upper extremity and shoulder girdle results in a dislocation of
the scapula from the thoracic wall.
Extensive soft tissue swelling and ecchymosis around the arm and shoulder are present, usually with
neurovascular and other injuries. Ninety percent of these patients have vascular injury, with the subclavian or
axillary arteries most commonly involved. Brachial plexus injury, often complete, is also reported in >90% of
cases.
Lateral displacement of the scapula on chest radiograph is the radiographic hallmark. Associated radiographic
abnormalities include distracted clavicle fracture, acromioclavicular separation, and sternoclavicular dislocation.
This severe injury may result in death or disability, with a flail extremity or amputation reported in over half the
survivors.8
Acromioclavicular Joint Injuries
Acromioclavicular joint injuries range from mild sprain to complete disruption of the ligaments that connect the
scapula and clavicle. The mechanism of injury is usually direct trauma to the acromioclavicular joint from a fall with
the arm adducted, as typically may occur in a sporting activity. An indirect mechanism is a fall on the outstretched
hand with transmission of force to the acromioclavicular joint. The result is that the scapula and shoulder girdle are
driven inferiorly while the clavicle remains in its normal position.
The acromioclavicular joint is a diarthrodial joint that, together with the sternoclavicular joint, connects the upper
extremity to the axial skeleton. Support of the acromioclavicular joint is through the acromioclavicular and
coracoclavicular ligaments, and the strong attachment of the trapezius and deltoid muscles (Figure 268-6).
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Surrounding the acromioclavicular joint is a thin capsule, which is reinforced by the acromioclavicular ligaments.
The superior fibers of this ligament blend with the fascia of the trapezius and deltoid muscles, which attach to the
clavicle and acromion. The acromioclavicular ligaments provide horizontal stability to the joint. The tough
coracoclavicular ligaments consist of two parts, the more lateral trapezoid and the medial conoid. They attach the
distal inferior clavicle to the coracoid process of the scapula. The coracoclavicular ligament is the major
suspensory ligament of the upper extremity and provides vertical stability to the acromioclavicular joint.
FIGURE 268-6.
Anatomy of the acromioclavicular joint.
The diagnosis of acromioclavicular joint injuries is clinical. The mechanism of injury, as well as tenderness and
deformity at the acromioclavicular joint, especially when compared with the opposite clavicle, is confirmatory.
Radiographs are useful for identifying other fractures and determining the severity of injury. Acromioclavicular
radiographs should specifically be ordered because they require only one third to one half the penetration of
standard shoulder films. Shoulder radiographs will overpenetrate the acromioclavicular joint, and small fractures
may be missed. Although standard acromioclavicular radiographs are generally sufficient, an axillary view is
required to identify posterior clavicular dislocation (type IV). The routine use of stress radiographs has been called
into question because of their low yield, although occult type III (see below) injuries can be unmasked only with
stress radiographs.9
Classification of Injury
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The Tossy and Allman classification of acromioclavicular joint injuries classically describes three types of injuries.
Rockwood describes three additional injuries (Figure 268-7). Types I, II, and III are common; types IV, V, and VI are
rare. The anatomic injury, radiographic findings, and physical findings are summarized in Table 268-2.
FIGURE 268-7.
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Classification of the acromioclavicular joint injuries.
Table 268-2 Classification and Physical Findings in Acromioclavicular Joint Injuries
Type
Injury
Radiograph
Examination
I
Sprained acromioclavicular
ligaments
Normal
Tenderness over
acromioclavicular
joint
II
Acromioclavicular ligaments
ruptured; coracoclavicular
ligaments sprained
Slight widening of
acromioclavicular joint; clavicle
elevated 25%–50% above
acromion; may be slight widening
of the coracoclavicular interspace
Tenderness and
mild step-off
deformity of
acromioclavicular
joint
III
Acromioclavicular ligaments
ruptured; coracoclavicular
ligaments ruptured; deltoid
and trapezius muscles
detached
Acromioclavicular joint dislocated
100%; coracoclavicular interspace
widened 25%–100%
Distal end of
clavicle
prominent;
shoulder droops
IV
Rupture of all supporting
structures; clavicle displaced
posteriorly in or through the
trapezius
May appear similar to type II and
III; axillary radiograph required to
visualize posterior dislocation
Possible
posterior
displacement of
clavicle
V
Rupture of all supporting
structures (more severe form
of type III injury)
Acromioclavicular joint dislocated;
generally 200%–300% disparity of
coracoclavicular interspace
compared to normal shoulder
More pain; gross
deformity of
clavicle
Acromioclavicular joint dislocated;
Severe swelling;
multiple
associated
VI
Acromioclavicular ligaments
disrupted; coracoclavicular
ligaments may be disrupted;
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deltoid and trapezius muscles
disrupted
clavicle displaced inferiorly
injuries
Treatment
Treatment of type I and II injuries consists of rest, ice, analgesics, and immobilization, followed by early
range-of-motion exercises (7 to 14 days).1,10 Various straps and braces have been used to reduce the
dislocation, but none have proven successful. A simple sling remains the most convenient and effective. Prognosis
for type I and II injuries is excellent, with only a small percentage of patients developing late symptoms requiring
excision of the distal clavicle. Treatment of type III injuries is controversial, with proponents for conservative or
operative philosophies.1,11 A trend, however, reveals a shift to conservative treatment with sling immobilization.
Both strategies have yielded good results in selected patients, with the specific management operator dependent.
Treatment decisions are based on such factors as age, occupation, and activity level. Types IV, V, and VI are
severe injuries, and most experts recommend surgical repair.1 Because other injuries are associated with
these more severe forms of acromioclavicular joint injuries (especially type VI), a careful clinical and radiographic
examination must be performed.
Dislocation of the Glenohumeral Joint
Anterior dislocations of the glenohumeral joint are the most common major joint dislocations. Posterior dislocations
account for <1% of shoulder dislocations. Other dislocations include inferior (luxatio erecta) and superior (very
rare).
Anterior Glenohumeral Dislocations
Table 268-3 describes the four types of anterior dislocations. These include subcoracoid, which is the most
common, subglenoid, subclavicular, and the very rare intrathoracic dislocation (Figure 268-8).
Table 268-3 Classification and Physical Findings in Dislocations of the Glenohumeral Joint
Type
Anterior
Subcoracoid
Description/Mechanism of Injury
Associated Injuries
Patient presentation:
Axillary nerve palsy
Arm is held in abduction and slight
external rotation with shoulder appearing
“squared off.”
Fracture of the greater tuberosity
Mechanism of injury:
Fracture of the humeral neck
Indirect blow with arm in abduction,
extension, and external rotation.
Disruption of the glenoid rim
(Bankart lesion)
Humeral head is displaced anterior to the
glenoid and inferior to the coracoid.
Axillary artery disruption
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Subglenoid
Humeral head lies inferior and anterior to
the glenoid fossa.
Subclavicular
Humeral head is displaced medial to the
coracoid below the clavicle.
Intrathoracic
Humeral head lies between the ribs and
thoracic cavity.
Posterior
Patient presentation:
Subacromial
Arm is adducted and internally rotated.
Subglenoid
Anterior shoulder is flat and the posterior
aspect full.
Subspinous
Coracoid process is prominent.
Fractures of the humeral shaft
Patient will not allow external rotation or
abduction because of severe pain.
Fractures of the lesser tuberosity
Fractures of the posterior glenoid
rim
Fractures of the humeral head
(reversed fractures of the Hill-Sachs
deformity)
Mechanism of injury:
Indirect force that produces forceful
internal rotation and adduction.
Inferior
(luxatio
erecta)
Patient presentation:
Severe soft tissue injuries
Patient is in severe pain.
Fractures of the proximal humerus
Humerus is fully abducted.
Rotator cuff tear
The elbow is flexed.
Neurovascular compression injuries
Patient’s hand is on or behind the head.
Humeral head can be palpated on the
lateral chest wall.
Mechanism of injury:
Neck of the humerus is levered against
the acromion and inferior capsule tears.
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Humeral head is forced out inferiorly.
FIGURE 268-8.
Types of anterior shoulder dislocations.
The combination of abduction, extension, and external rotation with sufficient force will cause an anterior
dislocation. The patient usually presents with the associated arm in slight abduction and external rotation. The
shoulder is “squared off,” lacking the normal rounded contour. The patient resists abduction and internal rotation.
The humeral head can often be palpated anteriorly. Because neurovascular injuries occur, a careful examination
must be performed. The axillary nerve is most commonly injured. This nerve may be tested by pinprick
sensation over the skin of the deltoid muscle.
Radiographs
AP and scapular lateral or “Y” radiographs should be obtained before reduction is attempted to confirm the
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anatomic type of dislocation and identify any associated fractures. Although the AP radiograph will reveal the
dislocation, the scapular Y radiograph will indicate whether the dislocation is anterior or posterior. Associated bony
injuries reported in the literature include fractures of the anterior glenoid lip [Bankart fracture, avulsion of glenoid
labrum (Figure 268-9)], greater tuberosity, coracoid, and acromion, and compression fractures of the humeral head
[Hill-Sachs lesion (Figure 268-10)]. The incidence of these minor fractures could be as high as 30%, but they do
not appear to change ED management.12
FIGURE 268-9.
Bankart fracture of the glenoid lip. (Reproduced with permission from
http://imagingsign.wordpress.com/2008/12/01/bankart-lesion-of-the-shoulder.)
FIGURE 268-10.
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Arrow points to the Hill-Sachs deformity, resulting from a prior anterior shoulder dislocation. (Reproduced with
permission from Simon RR, Sherman SC, Koenigsknecht SJ: Emergency Orthopedics, The Extremities, 5th ed. ©
2007, McGraw-Hill Inc., New York.)
Prereduction radiographs are advisable when there has been significant trauma, unless time is crucial because
circulation is threatened. Radiographs are needed because dislocations and fracture-dislocations may have a
similar appearance on physical examination, but the techniques used to treat them may be very different. Shoulder
dislocations or subluxations combined with proximal humerus fractures generally require orthopedic
consultation and may need operative repair. Postreduction radiographs are valuable for confirming the success
of the procedure, as well as for providing documentation, in the event the joint re-dislocates after the patient is
discharged from the ED.
There is an expenditure of time, money, and radiation associated with pre- or postreduction films. Although, as of
this writing, there are no evidence-based guidelines for identifying those patients who can be successfully treated
without pre- or postreduction films, in clinical practice films are sometimes omitted in patients with a history of
multiple recurrent dislocations of the shoulder who present with history, signs, and symptoms typical of another
recurrence in the absence of significant trauma. Postreduction films may not change ED management.12 If
validated, the Quebec decision rule for radiography in shoulder dislocation holds promise for a moderate decrease
in prereduction films and a large decrease in postreduction films.13
Reduction Techniques
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Many reduction techniques have been described.14,15 The three main categories are traction, leverage, and
scapular manipulation.16 Success rates are between 70% and 96% regardless of technique. The use of
procedural sedation is highly recommended, but any reduction technique may be attempted without medication
when performed slowly and atraumatically. It is important for the physician to be comfortable with two or three
techniques in case of a failed first attempt. Considerations in selection of a technique include ease of performance,
effectiveness, requirement for sedation, number of assistants, and duration. Intra-articular injection of 10 to 20 mL
1% lidocaine (10 mL provides a total dose of 100 milligrams of lidocaine) reduces the pain associated with
reduction, and is now a widely used alternative or complement to procedural sedation.17,18 After sterile skin
preparation, introduce the needle at the hollow created by the displaced humeral head, just inferior to the
acromion. Neurovascular examination should always be performed before and after reduction.
Hippocratic or Traction-Countertraction Technique (Modified)
A modification of the Hippocratic method uses traction-countertraction (Figure 268-11). The patient is supine with
the arm abducted and elbow flexed at 90 degrees. A sheet is tied and placed across the thorax of the patient and
then around the waist of the assistant. Another sheet is tied and placed around the forearm of the patient at the
elbow and the waist of the physician. The physician gradually applies traction as the assistant provides
countertraction. Gentle internal and external rotation or outward pressure on the proximal humerus may aid
reduction.
FIGURE 268-11.
Modified Hippocratic technique.
Stimson Technique
The patient is placed prone on a gurney with the dislocated extremity hanging over the side and a 10-lb weight
attached to the wrist. Intra-articular lidocaine should be injected before the procedure. Complete muscle relaxation
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is required. Reduction occurs in 20 to 30 minutes. Although safe, effective, and easy to learn, the time involved and
monitoring are drawbacks to this technique.
Milch Technique
With the patient supine, the physician slowly abducts and externally rotates the arm to the overhead position
(Figure 268-12). With the elbow fully extended, traction is applied. With the other hand, pressure may be placed on
the humeral head to manipulate it over the lip of the glenoid. This technique is well tolerated by the patient,
effective, and atraumatic. It is the technique of choice for many physicians.
FIGURE 268-12.
Milch technique.
Scapular Manipulation Technique
The patient is positioned with weights in the same manner as the Stimson technique (Figure 268-13). After
adequate sedation, the physician pushes the tip of the scapula medially using the thumbs, while stabilizing the
superior aspect with the cephalad hand. This technique has been found to have a 96% success rate.19
FIGURE 268-13.
Scapular manipulation technique.
External Rotation Technique
The patient is supine with the arm adducted to the patient’s side. With the elbow at 90 degrees of flexion, the arm
is slowly externally rotated (Figure 268-14). No longitudinal traction is applied. It is important to perform the
movement slowly to allow time for spasm and pain to resolve. Reduction is usually complete before reaching the
coronal plane and is often not noted either by the patient or physician. This technique has been found to have a
78% success rate.
FIGURE 268-14.
A and B. External rotation technique. (Reproduced with permission from Simon RR, Sherman SC, Koenigsknecht
SJ: Emergency Orthopedics, The Extremities, 5th ed. © 2007, McGraw-Hill Inc., New York.)
After reduction, place the arm in a shoulder immobilizer or sling that maintains the shoulder in adduction and
internal rotation. Some studies have shown that immobilization in adduction and external rotation may reduce
recurrence.14,16
Complications
Complications are frequently encountered in patients with anterior glenohumeral dislocations.20 The most
common complication is recurrent dislocation, which is age dependent. Patients <20 years of age may have a
>90% recurrence; those >40 years have a 10% to 15% recurrence.20,21 Early surgical repair, open or
arthroscopic, may significantly decrease the recurrence rate. Patients with first-time shoulder dislocations should
be referred for orthopedic evaluation.22–24 Other complications include fractures and injuries to nerves and to the
rotator cuff. Vascular injuries are rare, but when they occur, they tend to involve the axillary artery in elderly
patients. Clinical findings of vascular injury include absent radial pulse, axillary hematoma, bruising of the lateral
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chest wall, and an axillary bruit.
Bony injuries are common and include fractures of the humeral head (Hill-Sachs lesion), anterior glenoid lip, and
greater tuberosity. Nerve injuries, which occur in 10% to 25% of acute dislocations, are the result of traction
neurapraxia. Most involve the axillary nerve. This injury is temporary and resolves spontaneously. The common test
of sensation over the skin of the deltoid muscle may not be reliable. Other nerves that may be injured are the radial,
ulnar, median, musculocutaneous, and brachial plexus.20
A frequent but often missed injury is a tear of the rotator cuff. The rotator cuff weakens with advancing age,
and as many as 86% of patients >40 years old with an anterior dislocation have an associated rotator cuff tear.
Pain or weakness 2 to 4 weeks after a glenohumeral dislocation is an indication for MRI or arthrogram. Early
diagnosis is important because prompt surgery yields the best results.
Posterior Glenohumeral Dislocations
Posterior dislocation may occur with the humeral head in the subacromial (most commonly with the humeral head
posterior to the glenoid and inferior to the acromion), subglenoid, or subspinous position (Figure 268-15). The
latter two are rare. The usual mechanism is an indirect force that produces forceful internal rotation and adduction.
This may occur during a fall or from violent muscle contraction due to a seizure or electric shock. A direct blow to
the anterior shoulder can also produce a posterior dislocation. On examination, there is a prominence of the
posterior shoulder and anterior flattening of the normal shoulder contour on the affected side, especially when
compared to the non-affected side. The patient will be unable to externally rotate or abduct the affected arm.
FIGURE 268-15.
Illustration of posterior shoulder dislocations.
Posterior dislocations are reported to be commonly missed. Clinical findings are described in Table 268-3.
Although the AP radiograph is helpful, the scapular Y radiograph is diagnostic. In this radiograph, the humeral head
is seen in a posterior position.
Reduction of a posterior dislocation is performed with the patient supine. Because severe pain and muscle spasms
are the norm, muscle relaxation and analgesia are paramount. Traction is applied to the adducted arm in the long
axis of the humerus. An assistant gently pushes the humeral head anteriorly into the glenoid fossa.25 Fractures of
the posterior glenoid rim, humeral head (reversed Hill-Sachs deformity), humeral shaft, or lesser tuberosity are
common complications. Neurovascular and rotator cuff tears are less common than in anterior dislocations.
Postreduction radiographs should be obtained to confirm successful reduction. The shoulder should be
immobilized with an arm sling, with follow-up with an orthopedist.
Inferior Dislocations (Luxatio Erecta)
Inferior dislocation is associated with significant soft tissue trauma or fracture. The mechanism of injury is a
hyperabduction force, which levers the neck of the humerus against the acromion. As the force continues, the
inferior capsule tears, and the humeral head is forced out inferiorly (Figure 268-16).
FIGURE 268-16.
Luxatio erecta. (Courtesy Rockford Health System.)
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The patient presents with the humerus fully abducted, the elbow flexed, and the patient’s hand on or behind the
head. The humeral head can be palpated on the lateral chest wall.
Reduction consists of traction in an upward and outward direction in line with the humerus (Figure 268-17). The
assistant applies countertraction. Reduction is signaled by a “clunk.” The arm is then brought to the patient’s side
and immobilized in a shoulder immobilizer.
FIGURE 268-17.
Reduction of luxatio erecta.
Complications include severe soft tissue injuries and fractures of the proximal humerus. The rotator cuff, which
usually becomes detached, requires orthopedic follow-up. Neurovascular compression injuries are usually found,
but almost always resolve after reduction. When the humeral head is buttonholed through the inferior capsule, the
dislocation is irreducible, and operative reduction is required.
Humerus Fractures
Proximal Humerus
Fractures of the proximal humerus typically occur in elderly osteoporotic patients. The proximal humerus is
composed of the articular segment and anatomic neck, the greater and lesser tuberosities, and the proximal shaft
(Figure 268-18). Muscles of the rotator cuff insert on the humeral tuberosities, and the biceps tendon travels
between them. The humeral circumflex arteries enter in the area of the bicipital groove and the tuberosities to
supply blood flow to the articular segment.
FIGURE 268-18.
Proximal humerus. (Reproduced with permission from Pansky B: Review of Gross Anatomy, 6th ed. New York,
McGraw Hill, 1995.)
Fractures usually occur through an indirect mechanism, such as a fall on an outstretched hand with the elbow
extended. Patients with fractures typically present with pain, swelling, and tenderness about the shoulder. Crepitus
and ecchymosis may be present, and the arm is generally held closely against the chest wall. Carefully perform
the neurovascular examination, as the brachial plexus and axillary arteries are near the coracoid process
and can be injured. The most commonly injured nerve is the axillary nerve, and sensation overlying the deltoid
muscle should be tested. Vascular injuries may occur with even trivial trauma in atherosclerotic elderly patients.
The most common vascular injury is the axillary artery and may be suggested by paresthesias, pallor,
pulselessness, or an expanding hematoma. The incidence of neurovascular injuries is high in both nondisplaced
and displaced fractures, but is much higher (>50%) in displaced fractures.
Radiographs consisting of AP, lateral shoulder, and axillary views will diagnose most proximal humerus fractures.
Fractures of the articular surface may be suggested by a fat fluid level or by a superior joint hematoma that
appears to push the humerus downward, as a “pseudosubluxation.”
To guide treatment, the Neer system classifies fractures about the shoulder into four “parts.” The proximal
humerus is divided into four “parts” based on epiphyseal lines, where fractures primarily occur: the articular
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surface of the humeral head; the greater tubercle; the lesser tubercle; and the shaft of the humerus (Figure 26819). The displacement of a fracture fragment from the proximal humerus is called a “part.” A “one-part” fracture
is one in which the fragment is not displaced at all, or is displaced <1 cm or is not angulated >45 degrees.
There can be multiple fragments, but if none of the fragments are displaced >1 cm or are angulated >45 degrees,
the proximal humerus fracture is termed “one-part.” Treatment of a “one-part” proximal humerus fracture
generally consists of immobilization (such as sling and swathe), ice, analgesics, and orthopedic referral.
Early exercise is important to avoid subsequent adhesive capsulitis. The prognosis is generally good. All other
proximal humerus fractures require orthopedic consultation in the ED because they are more frequently associated
with complications and are often difficult to manage. Closed reduction, operative treatment, or a combination of
the two may be necessary.
FIGURE 268-19.
The four parts of the humerus according to the Neer classification: 1, articular surface of the humeral head; 2,
greater tubercle; 3, lesser tubercle; 4, diaphysis or shaft of humerus. “One-part” is defined as a fracture fragment
displaced by <1 cm or <45 degrees; two-, three-, and four-part fractures have more displacement and angulation.
Greater tuberosity fractures accompany up to 15% of anterior shoulder dislocations. Significant displacement of a
greater tuberosity fracture implies a concomitant rotator cuff tear, with surgical repair often necessary for the active
patient. Fracture of the lesser tuberosity should alert the examiner to a potential posterior shoulder dislocation.
Any fracture involving the anatomic neck or the articular surface may result in compromise of the blood supply to
the articular segment. Ischemic necrosis of the articular segment may ultimately require insertion of a humeral head
prosthesis. Significantly angulated surgical neck fractures are a risk for neurovascular damage (axillary
neurovascular structures as well as the brachial plexus) and should be immediately immobilized and radiographed
in the position of presentation.
Children may have significant displacement or separation of the proximal humeral epiphysis and may need early
orthopedic consultation for anatomic reduction if near skeletal maturity. Salter II injuries are most common after
age 6 years old and will require closed reduction if >20 degrees of angulation is present. A shoulder spica is often
used after reduction for unstable injuries, with sling and swathe immobilization for other injuries.
Humerus Shaft
Fractures of the humeral shaft occur in a bimodal age distribution, with peaks in the third and seventh decades of
life, representing active young men and osteoporotic elderly women, respectively.
Humeral shaft fractures may be caused by a direct blow that produces a bending force, which results in a
transverse fracture. They may also be caused by an indirect mechanism, such as a fall on an outstretched hand,
that produces a torsion force, resulting in a spiral fracture. A combination of bending and torsion forces results in
an oblique fracture, sometimes with comminution, producing the “butterfly” fragment. The humerus is also a
common site of pathologic fractures, especially from metastatic breast cancer.
The most common site of fracture is the middle third of the humerus. Displacement of fracture fragments is
common as a result of the insertions and actions of the various muscles (deltoid, biceps, triceps, supraspinatus,
and pectoralis major) that act on the upper arm (Figure 268-20).
FIGURE 268-20.
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Humeral fractures anterior view. The actions of the muscles inserting on the humeral shaft determine fracture
angulation and displacement. A. Angulation of fragments with fracture line distal to rotator cuff insertion. B.
Angulation of fragments with fracture line distal to pectoralis major insertion. C. Angulation of fragments with
fracture line distal to deltoid insertion.
Clinical examination reveals localized tenderness, swelling, pain, and abnormal mobility or crepitus on palpation.
Displaced fractures are associated with shortening of the upper extremity. Attention must be given to the initial
neurovascular status, and reevaluation must be performed, especially after manipulation.
Radiographs should include two views of the humerus, and encompass the shoulder and elbow as well.
The vast majority of closed fractures of the shaft of the humerus are managed nonoperatively. The treatment of
uncomplicated fractures includes immobilization, ice, analgesia, and referral. Closed treatment options include the
coaptation splint (sugar tong), hanging cast, functional bracing, and external fixation. A simple sling and swathe
are adequate for the emergency management of most such patients. Some surgeons favor internal fixation for
patients with multiple trauma, transverse fracture lines, very proximal or very distal humerus fractures, pathologic
fractures, and fractures associated with neurovascular injuries.
Complications may include injury to the brachial artery or vein, or the radial, ulnar, or median nerves. A
radial nerve injury, which is the most common, may be manifested by a wrist drop and altered sensation at
the dorsal thumb index web space. The incidence of radial nerve palsy ranges from 10% to 20%. Fractures of
the distal third are particularly prone to entrapment of the radial nerve, either as a result of the initial injury or after
closed reduction. The majority of patients, however, will have eventual return of nerve function without operative
intervention.
Brachial Plexus Injuries
The brachial plexus (Figure 268-21) and its peripheral nerve branches are infraclavicular and lay anteromedial to
the glenohumeral joint. The brachial plexus is derived from the C4-T1 cervical roots and ultimately from the lateral,
posterior, and medial cords. At the lateral border of the pectoralis minor, these cords divide into the peripheral
nerves of the upper extremity.
FIGURE 268-21.
Brachial plexus.
Injuries to the brachial plexus can occur from penetrating, compression, or closed traction injuries. Injuries can be
divided into supraclavicular (roots and trunks) or infraclavicular (cords and terminal nerves) injuries.
High-speed motor vehicle or motorcycle crashes result in traction injuries as nerves are stretched longitudinally,
with simultaneous traction of the arm and opposite distraction of the head.26
The initial identification of brachial plexus injuries is often overshadowed by the presence of other severe injuries.
The most common of these is closed head injury, with chest trauma, fractures of nearby structures (clavicle,
scapula, and long bones), shoulder dislocation, and trauma to the subclavian or neck vessels also frequently
encountered. Significant swelling and soft tissue injury to the neck and shoulder girdle suggest traumatic forces
sufficient to injure the brachial plexus. The accumulation of cerebrospinal fluid from avulsed spinal roots may
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cause swelling in the posterior triangle. Horner syndrome (ipsilateral ptosis, miosis, and anhidrosis of the face) may
be present due to adjacent ganglion damage. However, brachial plexus injury may not be clinically apparent until a
responsive patient can indicate the extent of motor and sensory deficits, days to weeks after initial stabilization and
treatment. Arm pain that is constant and burning in character is common. Upper limb and shoulder girdle motor
and sensory deficits define the extent of damage to the brachial plexus. Adduction and internal rotation of the
shoulder indicates weakness of the deltoid and infraspinatus muscles (C5), whereas elbow extension is due
to weakness of the biceps (C6), and flexion of the digits and wrists is due to weakness of the extensors
(C7). The sensory distributions of the cervical roots and the peripheral nerves are shown in Figure 268-22.
FIGURE 268-22.
Sensory distribution of the brachial plexus.
MRI and CT myelography are common radiographic imaging procedures. Electromyographic and nerve conduction
velocity studies may aid in diagnosis, and surgical exploration of the area may be necessary. The delineation of
pre- and postganglionic injury may not be possible until wallerian degeneration is completed 2 weeks after injury.
Treatment and prognosis will depend on the location and extent of nerve damage.27 Complete supraclavicular
traction injuries with rupture of the nerve roots from the spinal cord may be the most devastating of all lesions of
the peripheral nerves. A multidisciplinary approach with nerve transfers and long-term physical therapy may
provide surprisingly good functional outcomes. In general, early neurosurgical consultation and timely referral to a
facility capable of handling the complex multiple-injured trauma patient will result in the best outcome.
Acknowledgment
The authors wish to acknowledge the editorial contributions of Christopher Sullivan.
References
1. Macdonald PB, Lapointe P: Acromioclavicular and sternoclavicular joint injuries. Orthop Clin North Am 39: 535,
2008. [PubMed: 18803982]
2. Gobet R, Meuli M, Altermatt S, et al: Medial clavicular epiphysiolysis in children: the so-called sterno-clavicular
dislocation. Emerg Radiol 10: 252, 2004. [PubMed: 15290471]
3. Wick M, Muller EJ, Kollig E, et al: Midshaft fractures of the clavicle with a shortening of more than 2 cm
predisposes to nonunion. Arch Orthop Trauma Surg 121: 2072, 2001.
4. Canadian Orthopaedic Trauma Society: Nonoperative treatment compared with plate fixation of displaced
midshaft clavicular fractures. J Bone Joint Surg Am 88: 35, 2006.
5. Nowak J, Holgersson M, Larsson S: Sequelae from clavicular fractures are common: a prospective study of 222
patients. Acta Orthop 76: 496, 2005. [PubMed: 16195064]
6. Cole PA: Scapular fractures. Orthop Clin North Am 33: 1, 2002. [PubMed: 11832310]
7. Sammarco VJ: Os acromiale: frequency, anatomy, and clinical implications. J Bone Joint Surg Am 82: 394,
2000. [PubMed: 10724231]
8. Althausen PL: Scapulothoracic dissociation: diagnosis and treatment. Clin Orthop Relat Res 416: 237, 2003.
[PubMed: 14646766]
9. Bossart PJ, Joyce SM, Manaster BJ, et al: Lack of efficacy of “weighted” radiographs in diagnosing acute
Page 21 of 24
2/28/15 1:09 PM
acromioclavicular separation. Ann Emerg Med 17: 20, 1988. [PubMed: 3337409]
10. Cox JS: Current method of treatment of acromioclavicular joint dislocations. Orthopedics 15: 1041, 1992.
[PubMed: 1437863]
11. Schlegel TF, Burks RT, Robin LD, et al: A prospective evaluation of untreated acute grade III acromioclavicular
separations. Am J Sports Med 29: 699, 2001. [PubMed: 11734479]
12. Kahn JH, Mehta SD: The role of post-reduction radiographs after shoulder dislocation. J Emerg Med 33: 169,
2007. [PubMed: 17692769]
13. Emond M, Lesage N, Lavoie A, Moore L: Refinement of the Quebec decision rule for radiography in shoulder
dislocation. CJEM 11: 36, 2009. [PubMed: 19166638]
14. Riebel GD, McCabe JB: Anterior shoulder dislocation: a review of reduction techniques. Am J Emerg Med
9:180, 1991. [PubMed: 1994950]
15. Cunningham NJ: Techniques for reduction of anteroinferior shoulder dislocation. Emerg Med Australasia 17:
463, 2005. [PubMed: 16302939]
16. Wen DY: Therapeutics: current concepts in the treatment of anterior shoulder dislocations. Am J Emerg Med
17: 401, 1999. [PubMed: 10452444]
17. Moharari RS, Khademhosseini P, Espandar R, et al: Intra-articular lidocaine versus intravenous
meperidine/diazepam in anterior shoulder dislocation: a randomized clinical trial. Emerg Med J 25: 262, 2008.
[PubMed: 18434457]
18. Miller SL, Cleeman E, Auerbach J, et al: Comparison of intra-articular lidocaine and intravenous sedation for
reduction of shoulder dislocations. J Bone Joint Surg Am 84: 2135, 2002. [PubMed: 12473699]
19. Kothari RU, Dronen SC: Prospective evaluation of the scapular manipulation technique in reducing anterior
shoulder dislocation. Ann Emerg Med 21: 1349, 1992. [PubMed: 1416331]
20. Beeson MS: Complications of shoulder dislocation. Am J Emerg Med 17: 288, 1999. [PubMed: 10337892]
21. Warme WJ, Arciero RA, Taylor DC: Anterior shoulder instability in sports: current management
recommendations. Sports Med 28: 209, 1999. [PubMed: 10541443]
22. Cleeman E, Flatow EL: Conservative management of shoulder injuries: shoulder dislocations in the young
patient. Orthop Clin North Am 31: 217, 2000. [PubMed: 10736391]
23. Styaner LR, Cummings J, Andersen J, et al: Conservative management of shoulder injuries: shoulder
dislocations in patients older than 40 years of age. Orthop Clin North Am 31: 231, 2000.
24. Walton J, Paxinos A, Tzannes A, et al: The unstable shoulder in the adolescent athlete. Am J Sports Med 30:
758, 2002. [PubMed: 12239016]
25. Kowalsky MS, Levine WN: Traumatic posterior glenohumeral dislocation: classification, pathoanatomy,
diagnosis, and treatment. Orthop Clin North Am 39: 519, 2008. [PubMed: 18803981]
26. Birch R: Injuries to the brachial plexus. Neurosurg Clin North Am 12: 285, 2001. [PubMed: 11525207]
27. Terzis J, Papakonstantinou K: The surgical treatment of brachial plexus injuries in adults. Plast Reconstr Surg
106: 1097, 2000. [PubMed: 11039383]
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Right posterior dislocation shows less visible right medial clavicle. (Courtesy of John Rudzinski, MD.)
Clavicle radiograph shows asymmetry of the clavicles. Arrow indicates asymmetric and inferiorly displaced medial
clavicle. (Courtesy of Rockford Health System.)
CT scan shows right posterior sternoclavicular dislocation. Arrow indicates disrupted sternoclavicular joint with
posterior displacement of clavicle and compression of adjacent lung. (Courtesy of Rockford Health System.)
Sternoclavicular joints. The relationship of the sternoclavicular joint to adjacent structures.
Sites of scapula fractures. A. Body. B. Glenoid rim. C. Intra-articular glenoid. D. Neck. E. Acromion. F. Spine. G.
Coracoid.
Anatomy of the acromioclavicular joint.
Classification of the acromioclavicular joint injuries.
Types of anterior shoulder dislocations.
Bankart fracture of the glenoid lip. (Reproduced with permission from
http://imagingsign.wordpress.com/2008/12/01/bankart-lesion-of-the-shoulder.)
Arrow points to the Hill-Sachs deformity, resulting from a prior anterior shoulder dislocation. (Reproduced with
permission from Simon RR, Sherman SC, Koenigsknecht SJ: Emergency Orthopedics, The Extremities, 5th ed. ©
2007, McGraw-Hill Inc., New York.)
Modified Hippocratic technique.
Milch technique.
Scapular manipulation technique.
A and B. External rotation technique. (Reproduced with permission from Simon RR, Sherman SC, Koenigsknecht
SJ: Emergency Orthopedics, The Extremities, 5th ed. © 2007, McGraw-Hill Inc., New York.)
Illustration of posterior shoulder dislocations.
Luxatio erecta. (Courtesy Rockford Health System.)
Reduction of luxatio erecta.
Proximal humerus. (Reproduced with permission from Pansky B: Review of Gross Anatomy, 6th ed. New York,
McGraw Hill, 1995.)
The four parts of the humerus according to the Neer classification: 1, articular surface of the humeral head; 2,
greater tubercle; 3, lesser tubercle; 4, diaphysis or shaft of humerus. “One-part” is defined as a fracture fragment
displaced by <1 cm or <45 degrees; two-, three-, and four-part fractures have more displacement and angulation.
Humeral fractures anterior view. The actions of the muscles inserting on the humeral shaft determine fracture
Page 23 of 24
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angulation and displacement. A. Angulation of fragments with fracture line distal to rotator cuff insertion. B.
Angulation of fragments with fracture line distal to pectoralis major insertion. C. Angulation of fragments with
fracture line distal to deltoid insertion.
Brachial plexus.
Sensory distribution of the brachial plexus.
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