I. Proximal Humerus Fractures
A. Epidemiology/overview
1. Proximal humeral fractures account for 4% to 5% of all fractures in adults.
2. Approximately three quarters of proximal humerus fractures in all age groups occur in women.
3. Among older individuals, most proximal humerus fractures result from low-energy falls.
4. Proximal humerus fractures resulting from high-energy injuries are more common in younger individuals.
B. Pathoanatomy
1. Vascularity of the proximal humerus (
Figure 1)
a. Most of the direct blood supply to the humeral head comes from the arcuate artery, which is supplied by the anterior circumflex humeral artery.
b. The fracture pattern can predict the status of the vascularity of the articular segment.
c. The posterior circumflex humeral artery sends branches to the articular segment and greater tuberosity posteromedially in the area of the capsular insertion.
d. Vascularity of the articular segment is more likely to be preserved if 8 mm or more of the calcar is attached to the articular segment.
2. Nerve injuries are more common with fracture-dislocations.
a. The axillary nerve is the most commonly injured peripheral nerve.
b. Greater tuberosity fracture-dislocations are most frequently accompanied by an isolated axillary nerve injury.
c. As diagnosed by electromyography, the prevalence of axillary and other nerve lesions in glenohumeral dislocations and humeral neck fractures is 20% to 30%; in patients older than age 50 years, it is as high as 50%.
C. Evaluation
1. History and physical examination
a. The history should assess for mechanism of injury, pre-injury functioning level, the presence of numbness or tingling in the extremity, and prior dislocation.
b. Early deltoid muscle atony with inferior subluxation of the humeral head can occur and must be distinguished from an axillary nerve injury.
c. Vascular examination
i. Most significant vascular injuries are arterial.
ii. The extensive collateral circulation may mask an arterial injury, and the distal pulses may be intact.
2. Imaging
a. Plain radiographs—In most cases, plain radiographs (the trauma series) are used to diagnose and classify proximal humerus fractures.
[Figure 1. Vascularity of the proximal humerus.]
[
Figure 2. Trauma series views of the proximal humerus. A, True AP view. There is no overlap of the humeral head and glenoid. B, Y (scapular lateral) view. The humeral head is in the center of the glenoid. The shape of the acromion can be evaluated to determine the cause of impingement or cuff tears. C, Axillary view. The glenoid can be evaluated for uneven wear or rim fractures. The unfused acromial epiphysis can be identified.]
[
Figure 3. The Neer classification of proximal humerus fractures.]
i. The true AP, Y (scapular lateral), and axillary views comprise the three orthogonal views of the trauma series (Figure 2).
ii. Posterior fracture-dislocations and displaced greater tuberosity fractures are the most commonly missed fractures of the proximal end of the humerus, usually because an axillary lateral view has not been obtained.
b. CT—Routine use of CT scanning is not indicated for proximal humerus fractures. However, if the AP position of the humeral head or the position of the greater tuberosity is at all uncertain or there is intra-articular comminution, a CT scan should be obtained.
c. MRI is rarely indicated for proximal humerus fractures.
D. Classification
1. Defining and identifying displacement is the most crucial aspect of fracture classification.
2. Codman recognized that proximal humerus fractures in adults occur along the lines of the old physeal scars, with injury patterns involving the four segments of the proximal humerus: the head, the greater tuberosity, the lesser tuberosity, and the shaft.
3. Neer classification (Figure 3)—A fracture is considered displaced if any major segment is displaced 1 cm or more or is angulated more than 45°.
4. Orthopaedic Trauma Association (OTA) comprehensive long-bone classification (
Figure 4)—Organizes proximal humerus fractures into three main groups and three additional subgroups based on fracture location; the presence of impaction, translation, angulation, or comminution of the surgical neck; and the presence or absence of a dislocation.
[Figure 4. OTA comprehensive long-bone classification of proximal humerus fractures (2007). Type A fractures are unifocal and involve the greater tuberosity or the surgical neck. Type B fractures are bifocal. Type C fractures include intraarticular anatomic neck and head-splitting fractures.]
5. Valgus-impacted fractures are not true four-part fractures and have preserved posterior medial capsular vascularity to the articular segment (
Figure 5).
E. Treatment
1. Nonsurgical—Nonsurgical treatment is not synonymous with skillful neglect.
a. Indications—Nonsurgical treatment is indicated for all minimally displaced or nondisplaced fractures. It is also indicated for displaced fractures when surgical treatment is contraindicated, ie, for elderly, low-demand patients; for uncooperative patients; and for patients with medical comorbidities or active infections elsewhere in the body.
b. Contraindications—Nonsurgical or closed treatment is contraindicated for many displaced fractures because it often yields unsatis factory results.
c. Nonsurgical treatment comprises a period of sling immobilization followed by progressive rehabilitation.
2. Surgical treatment/procedures
a. Closed reduction and percutaneous pinning (
Figure 6)
i. Indications—Primarily indicated for displaced surgical neck fractures in patients
[Figure 5. True AP radiographs of a valgus-impacted proximal humerus fracture. A, Radiograph obtained at the time of injury demonstrates the valgus position of the articular segment, which is impacted between the tuberosities. B, The postoperative radiograph demonstrates anatomic repositioning of the articular segment after open reduction and minimal internal fixation with heavy sutures.]
[Figure 6. Displaced (angulated) two-part surgical neck fracture of the proximal humerus. A, Preoperative AP view. B, AP fluoroscopic view after treatment with closed reduction and percutaneous pinning]
who have good bone quality; it is also indicated for some three-part fractures and valgus-impacted four-part fractures.
ii. Contraindications—Metaphyseal comminution is particularly problematic, and it is a relative contraindication.
b. Open reduction and internal fixation (ORIF)
i. Bone quality for internal fixation is probably the single most important technical consideration.
ii. Indications—ORIF is indicated for displaced two- and three-part fractures; four-part fractures or head-splitting fractures in younger patients (age ≤45 years).
iii. Contraindications—ORIF is contraindicated for patients who are poor surgical candidates and for older patients who have displaced four-part fractures.
iv. Surgical approaches for ORIF
(a) Deltopectoral approach—Most common approach; access to posteriorly displaced greater tuberosity fractures can be difficult.
(b) Superior deltoid-splitting approach—Appropriate for greater tuberosity fractures and valgus-impacted four-part fractures, but this approach increases the risk of axillary nerve injury.
v. ORIF—Plate and screw fixation
(a) Indications—Plate and screw fixation is used to achieve axial and rotational stability in proximal humerus fractures that involve the surgical neck. It is applicable to most fracture types.
[
Figure 7. Angular stable plate and screw fixation of a proximal humerus fracture using a locking plate.]
(b) Angular stable plate (blade plate and proximal humeral locking plate) and screw fixation achieves more stable fixation (Figure 7). For displaced tuberosity fractures, heavy sutures are used to stabilize and fix the tuberosities.
vi. ORIF—Limited internal fixation
(a) Limited internal fixation can be achieved with plates, intramedullary rods, or a combination of pins, heavy sutures, wires, or screws.
(b) Indications—Isolated greater and lesser tuberosity fractures, surgical neck fractures without comminution, some three-part fractures, and valgus-impacted four-part fractures.
(c) Contraindications—Limited internal fixation is contraindicated for patients who are poor surgical candidates.
c. Intramedullary internal fixation
i. Indications—Displaced surgical neck fractures or three-part greater tuberosity fractures.
ii. Contraindications—Intramedullary internal fixation is contraindicated for patients with
[
Figure 8. Head-splitting, three-part proximal humeral fracture in a 70-year-old woman treated with arthroplasty of the proximal humerus. A, Preoperative true AP view. B, Postoperative AP radiograph after successful treatment with a humeral head replacement.]
severe comminution of the proximal humerus.
d. Humeral head replacement (hemiarthroplasty) (Figure 8)
i. Indications—Four-part fractures and fracture-dislocations; three-part fractures and fracture-dislocations in which stable internal fixation cannot be achieved.
ii. Contraindications—Humeral head replacement is contraindicated for patients who are poor surgical candidates.
iii. The results of humeral head replacement are variable, and they are dependent on greater tuberosity healing and rotator cuff function.
iv. Replacement of the humeral head soon after an acute proximal humerus fracture has been shown to have a better outcome than performing the procedure later.
e. Total shoulder arthroplasty is rarely indicated.
f. Reverse total shoulder replacement can be considered for older patients with nonreconstructible tuberosity fractures, although this is currently controversial.
F. Complications
1. Malunion is a common sequela of proximal humerus fractures.
a. Surgical neck fractures tend to heal with a varus apex anterior malunion, which can result in limited shoulder elevation and subacromial impingement.
b. Malunion of the greater tuberosity can be either posterior or superior.
i. Superior malunion of the greater tuberosity of as little as 3 mm can lead to subacromial impingement.
ii. Posterior malunion of the greater tuberosity can block external rotation of the shoulder.
2. Nonunion
a. Surgical neck nonunions are usually atrophic and unstable.
b. Surgical treatment—ORIF with bone graft, humeral head replacement, or reverse total shoulder replacement (only for cases of very chronic nonunion in older patients with poor rotator cuff function).
3. Posttraumatic arthritis can result from articular injury to the humeral head and osteonecrosis.
4. Osteonecrosis
5. Infection
G. Pearls and pitfalls
1. Complete and detailed imaging studies are required for accurate diagnosis and treatment of proximal humerus fractures.
2. Most proximal humerus fractures (85%) are managed nonsurgically.
3. Medial/calcar and surgical neck comminution must be neutralized with ORIF.
H. Rehabilitation
1. Sling immobilization
2. Passive range of motion (ROM) 1 to 2 weeks after surgery
3. Active ROM at 6 to 8 weeks after surgery (or earlier, if there are radiographic signs of healing)
4. Progressive ROM and strengthening exercises as tolerated thereafter
II. Sternoclavicular Joint Dislocations
A. Epidemiology/overview
1. Overall, sternoclavicular (SC) joint injuries are uncommon, accounting for about 3% of shoulder girdle injuries.
2. Motor vehicle accidents and sports injuries are the most common causes of SC joint injury.
3. Anterior SC dislocations are more common than posterior dislocations.
B. Evaluation
1. History—Mechanism of SC joint dislocation (
Figure 9)
a. Direct force to the medial aspect of the clavicle pushes the clavicle posteriorly behind the sternum and into the mediastinum.
b. Indirect force on the lateral aspect of the shoulder is the most common mechanism of injury.
2. Physical examination
a. SC joint dislocation should prompt a search for associated musculoskeletal or visceral injuries.
b. Anterior dislocation
i. The medial end of the clavicle is prominent relative to the sternum.
ii. An anterior dislocation of the medial end of the clavicle can be fixed or mobile (an unstable joint that dislocates and reduces with shoulder ROM).
[Figure 9. Mechanism of sternoclavicular (SC) joint dislocation. A, A posterolateral compressive force is applied to the shoulder, and the medial end of the clavicle is displaced posteriorly. B, A lateral compressive force is applied to the anterior shoulder, resulting in an anterior SC joint dislocation.]
c. Posterior dislocation
i. Posterior dislocation is usually more painful than anterior dislocation.
ii. A visible or palpable indentation may be noted next to the sternum.
iii. Venous congestion and swelling may be evident in the neck or upper extremity.
iv. Compression of the trachea and/or esophagus can cause difficulty with breathing and swallowing.
3. Imaging
a. Plain radiographs
i. Routine AP views
ii. Serendipity view—A 40° cephalic tilt view of the sternum and clavicle (
Figure 10)
b. Advanced imaging—CT is the best imaging modality for SC joint dislocations and adjacent soft-tissue injuries.
C. Classification—SC joint dislocations are classified as anterior or posterior.
D. Treatment
1. Nonsurgical
a. Most SC joint dislocations are treated nonsurgically.
b. Traumatic anterior subluxation—Usually treated with pain management and short-term immobilization. A figure-of-8 sling may be used.
c. Traumatic anterior dislocation—Closed reduction is usually unstable. Studies report better results with nonsurgical treatment.
d. Traumatic posterior dislocation—Treatment comprises closed reduction. This is performed under controlled circumstances in the operating room with the patient under general anesthesia, to minimize the risk of injury to critical vascular structures. Closed reduction is usually stable.
2. Surgical
a. Indications—Surgery is indicated when closed reduction of an acute traumatic posterior dislocation has failed, or when an unreduced dislocation is chronic and symptomatic.
b. Contraindications—Contraindications to surgery include recurrent atraumatic SC joint instability. Chronic anterior SC joint dislocations can usually be treated with skillful neglect.
c. Surgical procedures
i. Acute traumatic posterior SC joint dislocations are treated with closed reduction. If closed reduction fails, open reduction of the joint and medial clavicle resection is performed with preservation of the SC joint ligaments (which are repaired). If the SC joint ligaments are attenuated and the medial clavicle is unstable, ligament reconstruction is performed.
ii. A chronic symptomatic anterior SC joint dislocation can be treated with medial clavicle resection. Ligament reconstruction is usually necessary.
iii. Sternocleidomastoid interposition arthroplasty is indicated for posttraumatic arthroplasty of the SC joint.
iv. Ligament reconstruction consists of tendon graft figure-of-8 reconstruction of the SC ligament.
[Figure 10. Illustration of a serendipity radiographic view, in which the patient is in the supine position and a 40° cephalic tilt view of the sternum and clavicle is obtained.]
E. Complications
1. Retrosternal and mediastinal injuries can occur, including various vascular, pulmonary, esophageal, cardiac, and neurologic injuries. A change in voice can indicate a concomitant injury; it can also occur as a postoperative complication.
2. Hardware migration—Metal implants should not be used to stabilize the SC joint because they can migrate and cause injury to intrathoracic or vascular structures.
3. Late degenerative changes can occur.
F. Pearls and pitfalls
1. A cardiothoracic surgeon should be on standby, or be present and ready to assist if necessary.
2. Avoid resecting >1 cm of medial clavicle to avoid injury to the costoclavicular ligament; resection results in increased instability.
G. Rehabilitation—Rehabilitation comprises a short period of sling immobilization followed by progressive ROM and strengthening exercises.
III. Clavicular Fractures
A. Epidemiology/overview
1. Clavicular fractures account for 5% to 10% of all fractures and 35% to 45% of shoulder girdle injuries.
2. As shown in
Figure 11, midshaft fractures account for about 80% of all clavicular fractures.
[Figure 11. Diagram of a clavicle showing the distribution of lateral-third, midshaft, and medial fracture patterns in adults. A, Superior view. B, Frontal view. C, Cross sections. Note that midshaft fractures account for approximately 80% of all clavicle fractures.]
3. Function—The clavicle suspends the upper extremity from the thorax and protects important underlying neurovascular structures.
B. Pathoanatomy/mechanism of injury
1. The clavicle is subcutaneous, with a poor muscle envelope and limited vascularity.
2. Injury—Most clavicular fractures result from a direct blow to the lateral aspect of the shoulder or from a fall onto the lateral shoulder. Fractures related to falls are the most common.
3. A small percentage of clavicular fractures are associated with more severe injuries, including scapular fractures, scapulothoracic dissociation, rib fractures, pneumothorax, and neurovascular compromise.
4. Stress fractures can result from overuse or after radiation therapy, although this is rare.
C. Evaluation
1. History—The patient may have had a direct blow to the lateral aspect of the shoulder or may have fallen onto the lateral shoulder.
2. Physical examination
[
Table 1. Neer Classification of Lateral-Third Clavicular Fractures as Modified by Rockwood*]
a. Assess for local superficial skin/soft-tissue injuries; open fractures, abrasions, skin tenting, inferior displacement of the shoulder girdle, swelling, and ecchymosis.
b. Perform a thorough neurovascular examination of the brachial plexus.
3. Imaging—Plain radiographs
a. AP view of the clavicle
b. 45° cephalic tilt view to evaluate superior/inferior or displacement
c. 45° caudal tilt view to better evaluate displacement in the AP plane
D. Classification—Clavicular fractures can be classified as lateral-third fractures (Table 1), midshaft fractures, or medial fractures.
1. Classification of lateral-third clavicular fractures is based on the integrity of the coracoclavicular ligament complex.
2. Midshaft fractures present with varying amounts of displacement and comminution.
[
Figure 12. Open reduction and internal fixation (ORIF) of a displaced lateral-third clavicle fracture using coracoclavicular sutures. A, AP internal rotation view of the shoulder shows displaced fracture of the lateral third of the clavicle. B, ORIF was performed with heavy sutures.]
3. Medial fractures are classified according to displacement and involvement of the SC joint.
E. Treatment
1. Lateral-third clavicular fractures
a. Nonsurgical
i. Nonsurgical treatment is appropriate for all nondisplaced or minimally displaced fractures.
ii. Complications—Nonunion is common with nonsurgical treatment.
b. Surgical
i. Indications—Surgical treatment is considered for displaced type II fractures because there is a high incidence of nonunion.
ii. Contraindications—Surgery is contraindicated for patients who are poor surgical candidates.
c. Surgical procedures
i. ORIF with a plate and screws is possible if the lateral fragment is long enough.
ii. If the lateral fragment is too small for plate fixation, coracoclavicular fixation of the medial fragment with heavy sutures can stabilize the reduction (Figure 12).
iii. Temporary fixation from the acromion to the lateral aspect of the clavicle can be used when the lateral clavicle fragment is small or comminuted.
iv. Fragment excision and coracoclavicular ligament reconstruction can be used when the lateral clavicle fragment is small.
d. Complications
i. Acromioclavicular (AC) joint arthritis
ii. Nonunion
iii. Loss of fixation
2. Midshaft clavicular fractures
a. Nonsurgical—Most midshaft clavicular fractures can be treated with nonsurgical modalities such as immobilization in a simple sling or a figure-of-8 harness.
b. Surgical
i. Indications—Surgery is indicated for open midshaft clavicular fractures or fractures with subclavian neurovascular injuries. Relative indications for surgery include skin compromise or tenting, and a displaced midshaft clavicular fracture associated with a scapular neck fracture or double disruption of the shoulder suspensory mechanism.
ii. Displacement of midshaft clavicular fractures correlates with healing rate. Recent studies show that fractures with 100% displacement and 2 cm of shortening do better with ORIF.
iii. For displaced midshaft clavicular fractures associated with flail chest, surgery facilitates pulmonary care.
iv. Contraindications—Surgery is contraindicated when minimal displacement and bone shortening are present.
c. Surgical procedures
i. Intramedullary screw fixation is used successfully but is less rigid than a plate.
[
Figure 13. ORIF of a displaced midshaft clavicle fracture with a plate and screws.]
ii. ORIF with a plate and screws is also used (Figure 13). The plate is usually placed superiorly or anteriorly. Stronger plates, such as 3.5-mm dynamic compression plates, are preferred.
d. Complications
i. Neurovascular injuries (supraclavicular nerve injury, iatrogenic vascular injury, or subclavian vein thrombosis)
ii. Hardware irritation or hardware failure; loss of fixation
iii. Infection
iv. Nonunion is more common with displacement and bone shortening. It is also associated with shoulder girdle pain and dysfunction.
3. Medial clavicular fractures
a. Nonsurgical—Most medial clavicular fractures are nondisplaced or minimally displaced and can be treated nonsurgically.
b. Surgical—Significant displacement of medial clavicular fractures, particularly posterior displacement into the lower neck or mediastinum, warrants consideration of ORIF.
c. Complications are the same as for posterior SC joint dislocation (see SC Joint Dislocations, section II.E).
F. Pearls and pitfalls
1. Scapulothoracic dissociation should be considered in the presence of severe displacement.
2. ORIF with a plate and screws puts the supraclavicular nerves at risk for injury.
3. Nonunion of a midshaft clavicular fracture can be successfully treated with ORIF and bone grafting as needed.
4. Displaced lateral-third clavicular fractures are inherently unstable and prone to nonunion.
G. Rehabilitation—Rehabilitation comprises a short period of sling immobilization followed by progressive ROM and strengthening exercises when clinical or radiographic signs of healing are present.
IV. Acromioclavicular Joint Separations
A. Epidemiology/overview
1. AC joint separations are more common in males.
2. Most AC joint separations occur during the second through fourth decades of life.
B. Pathoanatomy—The AC joint is diarthrodial and has less than 10° of motion. The upper extremity is suspended from the lateral clavicle by the coracoclavicular (conoid and trapezial) and AC ligaments. The AC ligaments give anteroposterior stability. The coracoclavicular ligaments give vertical or superior/inferior stability. Injury to these ligaments can cause instability of the AC joint, thereby causing the joint to dislocate or separate.
C. Evaluation
1. History—A fall onto the superior aspect or "point" of the shoulder is the typical mechanism of injury.
2. Physical examination
a. Observe shoulder posture and contour in upright position.
b. Palpate the AC joint and lateral clavicle.
c. Palpate mobility of the acromion relative to the lateral clavicle.
d. Check for instability in the vertical and horizontal planes.
3. Imaging—Plain radiographs
a. AP shoulder views
b. Zanca view—10° to 15° cephalic tilt to give unobstructed view of the AC joint
c. The axillary view will demonstrate posterior displacement in a type IV injury to the AC joint.
d. Stress views are no longer commonly used.
D. Classification
1. The Rockwood modified classification of ligamentous injuries to the AC joint (
Figure 14) is based on the extent of injury to the AC ligaments, the coracoclavicular ligaments, and the deltoid and trapezius muscle attachments to the lateral clavicle.
2. AC joint separation can occur with intact coracoclavicular ligaments in association with a fracture at the base of the coracoid.
[Figure 14. Rockwood modified classification of ligamentous injuries to the AC joint. Type I: A mild force applied to the point of the shoulder does not disrupt either the AC or the coracoclavicular ligaments. Type II: A moderate to heavy force applied to the point of the shoulder disrupts the AC ligaments, but the coracoclavicular ligaments remain intact. Type III: When a severe force is applied to the point of the shoulder, both the AC and the coracoclavicular ligaments are disrupted. Type IV: The ligaments are disrupted and the distal end of the clavicle is displaced posteriorly into or through the trapezius muscle. Type V: A violent force applied to the point of the shoulder not only ruptures the AC and coracoclavicular ligaments, it also disrupts the muscle attachments and creates a major separation between the clavicle and the acromion. Type VI: An inferior dislocation of the distal clavicle is shown, in which the clavicle is inferior to the coracoid process and posterior to the biceps and coracobrachialis tendons. The AC and coracoclavicular ligaments are disrupted.]
E. Treatment
1. Nonsurgical
a. Nonsurgical treatment, such as the use of a simple sling for comfort, is indicated for type I, type II, and most type III separations. Use of straps and harnesses is associated with shoulder stiffness and superficial soft-tissue injury.
b. With nonsurgical treatment, most patients regain substantial active motion and functional use of the arm within 6 weeks.
2. Surgical
a. Indications—Surgery is indicated for some type III and all type IV, V, and VI separations.
b. Contraindications—Contraindications include medical comorbidities, poor patient compliance with the postoperative rehabilitation program, and skin abrasion in the area of the surgical field.
c. Surgical procedures—Open reduction of the AC joint with or without distal clavicle resection and deltotrapezial fascia repair.
i. Primary coracoclavicular fixation with coracoclavicular screw
ii. Primary coracoclavicular fixation with coracoclavicular suture
(a) The suture is passed through drill holes in the clavicle rather than around the clavicle.
(b) The suture material is passed under the base of the coracoid or fixed to the base of the coracoid with suture anchors.
iii. Coracoclavicular ligament reconstruction
(a) Modified Weaver-Dunn transfer of the AC ligament to the distal clavicle with or without coracoclavicular fixation (
Figure 15)
[Figure 15. Schematic drawing of the modified Weaver-Dunn procedure demonstrating coracoclavicular fixation with two heavy No. 5 nonabsorbable sutures combined with transfer of the coracoaccromial ligament to the distal clavicle. A minimal (5 to 7 mm) resection of the distal clavicle has been performed.]
(b) Reconstruction of the coracoclavicular ligaments with a free tendon graft
iv. Primary AC joint fixation can be performed with wires or pins; however, this method has a high complication rate.
v. Dynamic muscle transfer of the short head of the biceps to the clavicle is not commonly used.
vi. Insertion of a clavicle hook plate has a high failure rate and requires a second procedure to remove the plate and screws.
F. Biomechanics of AC joint repair
1. Coracoacromial ligament transfer alone is only 20% as strong as the intact coracoclavicular ligaments.
2. Free tendon graft reconstruction most closely approximates the strength of the intact coracoclavicular ligaments.
G. Complications
1. Nonsurgical treatment complications
a. Late AC arthritis can occur after type I and type II injuries.
b. Anterior posterior instability or subluxation due to AC ligament injury is an uncommon and subtle sequela of type II injuries.
2. Surgical treatment complications
a. Wound infection
b. Loss of fixation or recurrence of deformity is probably more common than reported or expected.
i. Smooth pin migration after fixation of the AC joint is a well-known complication that can be avoided by bending the end of the pin and observing the patient closely.
ii. Circumferential suture fixation around the clavicle can erode and result in a distal-third clavicle fracture.
iii. Isolated soft-tissue repair without coracoclavicular fixation is prone to failure.
H. Pearls and pitfalls
1. Avoid overaggressive rehabilitation.
2. Reinforce soft-tissue repairs with coracoclavicular fixation.
3. Passing the sutures around the coracoid is done carefully to avoid neurovascular injuries.
I. Rehabilitation
1. Sling immobilization with or without abduction for 6 weeks after surgery
2. Shoulder ROM exercises are avoided for 6 weeks.
3. Release to full activity at least 6 months after surgery
V. Scapular and Glenoid Fractures
A. Epidemiology/overview
1. Scapular fractures represent 3% to 5% of all shoulder girdle injuries.
2. The mean age of patients with scapular fractures is 35 to 45 years.
3. Approximately 60% to 75% of scapular fractures result from a motor vehicle or motorcycle accident.
B. Pathoanatomy
1. Mechanisms of injury
a. Displacement is the result of the initial energy of the injury and the pull of muscular attachments.
b. Axial load on the outstretched upper extremity can cause scapular neck and glenoid fossa fractures.
c. Scapular and glenoid fractures usually result from high-energy, direct blunt-force trauma.
d. Glenohumeral dislocation can cause glenoid fractures.
e. Traction injury can cause avulsion fractures.
[
Table 2. Classification of Coracoid Fractures]
2. Associated injuries—The high-energy mechanism of injury associated with scapular and glenoid fractures often results in other injuries.
a. Chest injuries, including rib fractures, pulmonary contusions, and hemothorax/pneumothorax can occur.
b. Ipsilateral clavicle fracture is associated with 20% to 40% of scapula fractures.
c. Brachial plexopathy can occur.
3. Scapulothoracic dissociation is a closed, lateral displacement of the scapula that is associated with severe soft-tissue injury of the scapulothoracic and thoracohumeral musculature and neurovascular injury (brachial plexus and vasculature of the upper limb).
C. Evaluation
1. History—Scapular fractures usually result from severe high-energy trauma
2. Physical examination
a. Identify associated injuries. Surrounding soft-tissue contusions and skin abrasions are common.
b. Baseline neurologic and vascular examinations are important.
3. Imaging
a. Plain radiographs—The trauma series is sufficient for most fractures.
b. Advanced CT imaging using multiple planes and three-dimensional reconstruction is very useful, especially for glenoid fractures.
D. Classification—Classification is based on the location of the fracture.
1. The classification of coracoid fractures is shown in Table 2.
2. The classification of acromial fractures is shown in
Table 3. With acromial fractures, it is important to distinguish between acute traumatic fracture and os acromiale nonunion.
[Table 3. Classification of Acromial Fractures]
3. The original classification of glenoid fractures proposed by Ideberg included five types; Goss added a sixth type. The Ideberg classification, as modified by Goss, is shown in
Figure 16.
4. Scapular neck fractures can occur with or without separation of the AC joint or clavicle fracture.
5. Scapulothoracic dissociation can be classified by the presence or absence of brachial plexus injury.
E. Treatment
1. Nonsurgical
a. Most scapular fractures, including all nondis-placed fractures, can be treated nonsurgically.
b. Many extra-articular scapular neck fractures are well tolerated, even when displaced.
c. Some severely comminuted glenoid fractures are best treated nonsurgically.
2. Surgical
a. Indications
i. Surgery is indicated for some displaced fractures of the acromion, glenoid, and scapular neck.
ii. Disruption of the superior shoulder suspensory mechanism can lead to discontinuity and malposition of the glenohumeral joint relative to the scapular body. Double disruptions of the superior shoulder suspensory complex (
Figure 17) require surgical treatment.
iii. Floating shoulder is a relative indication for surgical treatment with ORIF of the displaced clavicle fracture, with or without ORIF of the scapular neck fracture.
b. Contraindication—Skin abrasion overlying the surgical field is a potential source of wound contamination and infection.
[Figure 16. Ideberg classification of glenoid fractures as modified by Goss. Type Ia: Anterior rim fracture. Type Ib: Posterior rim fracture. Type II: Fracture line through the glenoid fossa exiting at the lateral border of the scapula. Type III: Fracture line through the glenoid fossa exiting at the superior border of the scapula. Type IV: Fracture line through the glenoid fossa exiting at the medial border of the scapula. Type Va is a combination of types II and IV. Type Vb is a combination of types III and IV. Type Vc is a combination of types II, III, and IV. Type VI: Comminuted fracture.]
[Figure 17. Superior shoulder suspensory complex. A, AP view of the bone-soft-tissue ring and superior and inferior bone struts. B, Lateral view of the bone-soft-tissue ring.]
c. Surgical procedures/approaches—A deltopectoral approach is used for anterior glenoid fractures and coracoid fractures, a superior approach is used for acromial fractures, and a posterior approach is used for scapular neck fractures and most glenoid fractures.
F. Complications
1. Complications of scapular fractures are primarily related to the severity of the traumatic injury and the associated injuries.
2. Malunion is generally well tolerated when it involves the scapular body and neck.
3. Suprascapular neuropathy is associated with scapular neck fractures.
4. Complications of surgical treatment of scapula fractures are relatively uncommon.
G. Pearls and pitfalls
1. High-energy injuries of the chest, ribs, and clavicle should prompt careful evaluation for scapular injury.
2. Shoulder function is predominantly determined by involvement of the glenoid articular fossa and scapular neck.
Top Testing Facts
Proximal Humerus Fractures
1. Fracture characterization and classification are essential in the evaluation and management of proximal humerus injuries. The fracture pattern can predict the status of the vascularity of the articular segment.
2. Greater tuberosity fracture-dislocations are most frequently accompanied by an isolated axillary nerve injury.
3. Closed reduction and percutaneous pinning is primarily indicated for treatment of displaced surgical neck fractures in patients who have good bone quality.
4. Bone quality for internal fixation is probably the single most important technical consideration.
5. Superior malunion of the greater tuberosity of as little as 3 mm can lead to subacromial impingement. Posterior malunion of the greater tuberosity can block external rotation of the shoulder.
SC Joint Dislocations
1. Most SC joint dislocations are treated nonsurgically.
2. Acute traumatic posterior SC joint dislocations are treated with closed reduction.
3. A chronic symptomatic anterior SC joint dislocation can be treated with medial clavicle resection. Ligament reconstruction is usually necessary.
4. Tendon graft figure-of-8 reconstruction of the SC ligament can be performed for recurrent SC joint instability.
5. Metal implants should not be used to stabilize the SC joint because they can migrate and cause injury to intrathoracic or vascular structures.
Clavicular Fractures
1. The clavicle is subcutaneous, with a poor muscle envelope and limited vascularity.
2. Classification of lateral-third clavicle fractures is based on the integrity of the coracoclavicular ligament complex.
3. Most midshaft clavicular fractures can be treated with nonsurgical modalities such as immobilization in a simple sling or a figure-of-8 harness.
4. Displacement of midshaft clavicular fractures correlates with healing rate.
5. ORIF is appropriate for some displaced midshaft clavicular fractures. Fractures with 100% displacement and 2 cm of shortening do better with ORIF.
6. Significant displacement of medial clavicular fractures, particularly posterior displacement into the lower neck or mediastinum, warrants consideration of ORIF.
AC Joint Separations
1. The Rockwood modified classification of ligamentous injuries to the AC joint is based on the extent of injury to the AC ligaments, the coracoclavicular ligaments, and the deltoid and trapezius muscle attachments to the lateral clavicle.
2. Nonsurgical treatment, such as the use of a simple sling for comfort, is indicated for type I, type II, and most type III separations.
3. Coracoacromial ligament transfer alone is only 20% as strong as the intact coracoclavicular ligaments.
4. Free tendon graft reconstruction of the coracoclavicular ligaments most closely approximates the strength of the intact coracoclavicular ligaments.
5. Isolated soft-tissue repair without coracoclavicular fixation is prone to failure.
Scapular and Glenoid Fractures
1. Scapular and glenoid fractures usually result from high-energy, direct blunt-force trauma. Displacement is the result of the initial energy of the injury and the pull of muscular attachments.
2. The high-energy mechanism of injury associated with scapular and glenoid fractures often results in other injuries (ie, chest injuries including rib fractures, pulmonary contusions, and hemothorax/pneumothorax can occur).
3. Most scapular fractures, including all nondisplaced fractures, can be treated nonsurgically.
4. Surgery is indicated for some displaced fractures of the acromion, glenoid, and scapular neck.
5. Disruption of the superior shoulder suspensory mechanism can lead to discontinuity and malposition of the glenohumeral joint relative to the scapular body.
6. Floating shoulder is a relative indication for surgical treatment with ORIF of the displaced clavicle fracture, with or without ORIF of the scapular neck fracture.
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