u01 clavicle ac_sc_joints1

ClavicleClavicle“S”-shaped bone Medial - sternoclavicular jointLateral - acromioclavicular joint and

coracoclavicular ligamentsMuscle attachments:

Medial: sternocleidomastoidLateral: Trapezius, pectoralis major

AC JointDiarthrodial joint between medial facet of

acromion and the lateral (distal) clavicle.Contains intra-articular disk of variable size.Thin capsule stabilized by ligaments on all

sides:AC ligaments control horizontal (anteroposterior )

displacementSuperior AC ligament most important

Distal Clavicle

Coracoclavicular ligaments“Suspensory ligaments of the

upper extremity”Two components:

Trapezoid Conoid

Stronger than AC ligamentsProvide vertical stability to AC

joint

Mechanism of InjuryModerate or high-energy traumatic impacts

to the shoulder1. Fall from height2. Motor vehicle accident3. Sports injury4. Blow to the point of the shoulder5. Rarely a direct injury to the clavicle

Physical ExaminationInspection

Evaluate deformity and/or displacement

Beware of rare inferior or posterior displacement of distal or medial ends of clavicle

Compare to opposite side.

Physical Examination

PalpationEvaluate painLook for instability with stress

Physical Examination

Neurovascular examinationEvaluate upper extremity motor and

sensationMeasure shoulder range-of-motion

Radiographic Evaluationof the Clavicle

Anteroposterior View

30-degree Cephalic Tilt View

Clavicle Fractures

Classification ofClavicle Fractures

Group I : Middle thirdMost common (80% of clavicle fractures)

Group II: Distal third10-15% of clavicle injuries

Group III: Medial thirdLeast common (approx. 5%)

Treatment OptionsNonoperative

SlingBrace

SurgicalPlate FixationScrew or Pin Fixation

Nonoperative Treatment“Standard of Care” for most clavicle

fractures.Continued questions about the need to wear

a specialized brace.

Simple Sling vs.Figure-of-8 Bandage

Prospective randomized trial of 61 patientsSimple sling

Less discomfortFunctional and cosmetic results identicalAlignment of healed fractures unchanged

from the initial displacement in both groups

Andersen et al., Acta Orthop Scand 58: 71-4, 1987.

Nonoperative TreatmentIt is difficult to reduce clavicle fractures by

closed means.Most clavicle fractures unite rapidly despite

displacementSignificantly displaced mid-shaft and distal-

third injuries have a higher incidence of nonunion.

Nonoperative TreatmentThere is new evidence that the outcome of

nonoperative management of displaced middle-third clavicle fractures is not as good as traditionally thought, with many patients having significant functional problems.

Deficits following nonoperative treatment of displaced midshaft clavicular fracturesA patient-based outcome questionnaire and

muscle-strength testing were used to evaluate 30 patients after nonoperative care of a displaced midshaft fracture of the clavicle.

At a minimum of twelve months (mean 55 mos), outcomes were measured with the Constant shoulder score and the DASH patient questionnaire. In addition, shoulder muscle-strength testing was performed with the Baltimore Therapeutic Equipment Work Simulator, with the uninjured arm serving as a control.

McKee et al. J Bone Joint Surg Am 2006;88-A:35-40.

Deficits following nonoperative treatment of displaced midshaft clavicular fracturesThe strength of the injured shoulder was

81% for maximum flexion, 75% for endurance of flexion, 82% for maximum abduction, 67% for endurance of abduction, 81% for maximum external rotation, 82% for endurance of external rotation, 85% for maximum internal rotation, and 78% for endurance of internal rotation (p < 0.05 for all).

The mean Constant score was 71 points, and the mean DASH score was 24.6 points, indicating substantial residual disability.

McKee et al. J Bone Joint Surg Am 2006;88-A:35-40.

Displaced midshaft clavicle fractures can cause significant, persistent disability, even if they heal uneventfully.

Definite Indications for Surgical Treatment of Clavicle Fractures

1) Open fractures2) Associated neurovascular injury

Relative Indications for Acute Treatment of Clavicle Fractures

1) Widely displaced fractures2) Multiple trauma3) Displaced distal-third

fractures

Relative Indications for Acute Treatment of Clavicle Fractures

4) Floating shoulder5) Seizure disorder6) Cosmetic deformity7) Earlier return to work.

Clavicular Displacement< 5 mm shortening: acceptable results at 5 years (Nordqvist et

al, Acta Orthop Scand 1997;68:349-51.> 20 mm shortening associated with increased risk of nonunion

and poor functional outcome at 3 years (Hill et al, JBJS 1997;79B: 537-9)

Plate FixationTraditional means of ORIFPlate applied superiorly or inferiorly

Inferior plating associated with lower risk of hardware prominence

Used for acute displaced fractures and nonunions.

Intramedullary FixationLarge threaded cannulated screwsFlexible elastic nailsK-wires

Associated with risk of migration

Useful when plate fixation contra-indicatedBad skinSevere osteopenia

Fixation less secure

Complications of Clavicular Fractures and its Treatment

NonunionMalunion Neurovascular SequelaePost-Traumatic Arthritis

Risk Factors for the Development of Clavicular Nonunions

Location of Fracture (outer third)

Degree of Displacement (marked displacement)

Primary Open Reduction

Principles for the Treatment of Clavicular NonunionsRestore length of clavicle

May need intercalary bone graftRigid internal fixation, usually with a plateIliac crest bone graft

Role of bone-graft substitutes not yet defined.

Clavicular MalunionSymptoms of pain, fatigue, cosmetic

deformity.Initially treat with strengthening, especially

of scapulothoracic stabilizers.Consider osteotomy, internal fixation in rare

cases in which nonoperative treatment fails.

Correction of malunion with thoracic outlet sx

Neurologic SequelaeOccasionally, fracture fragments or abundant

callus can cause brachial plexus symptoms.Treatment is reduction and fixation of the

fracture, or resection of callus with or without osteotomy and fixation for malunions.

Classification of Distal Clavicular Fractures(Group II Clavicle Fractures)

Type I-nondisplaced Between the CC and

AC ligaments with ligament still intact

From Nuber GW and Bowen MK, JAAOS, 5:11, 1997

Classification of Distal Clavicular Fractures

Type IITypically displaced secondary to a

fracture medial to the coracoclavicular ligaments, keeping the distal fragment reduced while allowing the medial fragmetn to displace superiorly

Highest rate of nonunion (up to 30%)Two Types

•A. Conoid and trapezoid attached to distal fragment

From Nuber GW and Bowen MK, JAAOS, 5:11, 1997

•Type IIB: Conoid torn, trapezoid attached

From Nuber GW and Bowen MK, JAAOS, 5:11, 1997

Classification of Distal Clavicular Fractures

Type III:articular fractures

From Nuber GW and Bowen MK, JAAOS, 5:11, 1997

Treatment of Distal-Third (Type II) Clavicle Fractures

Nonoperative treatment 22 to 33% failed to unite 45 to 67% took more than three months to

heal

Operative treatment 100% of fractures healed within 6 to 10

weeks after surgery

Displaced Type II fractures of the distal clavicle are often treated more aggressively because of the increased risk of nonunion with nonoperative treatment

Techniques for Acute Operative Treatment of Distal Clavicle Fractures

Kirschner wires inserted into the distal fragment

Dorsal plate fixationCC screw fixation Tension-band wire or sutureTransfer of coracoid process to the

clavicleClavicular Hook Plate

For most techniques of clavicular fixation, coracoclavicular fixation is also needed to prevent redisplacement of the medial clavicle.

• The Hook Plate (Synthes USA, Paoli, PA) was specifically designed to avoid this problem of redisplacement.

Hook Plate - ResultsRecent series of distal clavicle fractuers

treated with the Hook Plate document high union rates of 88% - 100%. Complications are rare but potentially significant, including new fracture about the implant, rotator cuff tear, and frequent subacromial impingement.

Indications for Late Surgery for Distal Clavicle Fractures

PainWeaknessDeformity

Radiographic Evaluation of the Acromioclavicular Joint

Proper exposure of the AC joint requires one-third to one-half the x-ray penetration of routine shoulder views

Initial Views:Anteroposterior view

Other views:Axillary: demonstrates anterior-posterior

displacementStress views: not generally relevant for

treatment decisions.

Type I Sprain of

acromioclavicular ligament

AC joint intact Coracoclavicular

ligaments intactDeltoid and trapezius

muscles intact

From Nuber GW and Bowen MK, JAAOS, 5:11, 1997

AC joint disrupted< 50% Vertical

displacementSprain of the

coracoclavicular ligaments

CC ligaments intactDeltoid and

trapezius muscles intact

Type II

From Nuber GW and Bowen MK, JAAOS, 5:11, 1997

Type III AC ligaments and CC

ligaments all disruptedAC joint dislocated and

the shoulder complex displaced inferiorly

CC interspace greater than the normal shoulder(25-100%)

Deltoid and trapezius muscles usually detached from the distal clavicle

From Nuber GW and Bowen MK, JAAOS, 5:11, 1997

Type III Variants “Pseudodislocation” through an

intact periosteal sleevePhyseal injuryCoracoid process fracture

Type IV AC and CC ligaments

disrupted AC joint dislocated

and clavicle displaced posteriorly into or through the trapezius muscle

Deltoid and trapezius muscles detached from the distal clavicle

From Nuber GW and Bowen MK, JAAOS, 5:11, 1997

Type V AC ligaments disrupted CC ligaments disruptedAC joint dislocated and

gross disparity between the clavicle and the scapula (100-300%)

Deltoid and trapezius muscles detached from the distal half of clavicle

From Nuber GW and Bowen MK, JAAOS, 5:11, 1997

Type VI AC joint dislocated

and clavicle displaced inferior to the acromion or the coracoid process

AC and CC ligaments disrupted

Deltoid and trapezius muscles detached from the distal clavicle

From Nuber GW and Bowen MK, JAAOS, 5:11, 1997

Treatment Options for Types I - II Acromioclavicular Joint Injuries

Nonoperative: Ice and protection until pain subsides (7 to 10 days).

Return to sports as pain allows (1-2 weeks)No apparent benefit to the use of

specialized braces.

Type II operative treatmentGenerally reserved only for the patient with

chronic pain.Treatment is resection of the distal clavicle and

reconstruction of the coracoclavicular ligaments.

Treatment Options for Type III-VI Acromioclavicular Joint InjuriesNonoperative treatment

Closed reduction and application of a sling and harness to maintain reduction of the clavicle

Short-term sling and early range of motion

Operative treatmentPrimary AC joint fixationPrimary CC ligament fixationExcision of the distal clavicle Dynamic muscle transfers

Type III Injuries: Need for acute surgical treatment remains very controversial.

Most surgeons recommend conservative treatment except in the throwing athlete or overhead worker.

Repair generally avoided in contact athletes because of the risk of reinjury.

Indications for Acute Surgical Treatment of Acromioclavicular Injuries

Type III injuries in highly active patients

Type IV, V, and VI injuries

Surgical Options for AC Joint InstabilityCoracoid process transfer to distal transfer

(Dynamic muscle transfer)Primary AC joint fixationPrimary Coracoclavicular FixationDistal Clavicle Excision with CC ligament

reconstruction.

Weaver-Dunn Procedure

The distal clavicle is excised.The CA ligament is

transferred to the distal clavicle.

The CC ligaments are repaired and/or augmented with a coracoclavicular screw or suture.

Repair of deltotrapezial fascia

From Nuber GW and Bowen MK, JAAOS, 5:11, 1997

Indications for Late Surgical Treatment of Acromioclavicular Injuries

PainWeaknessDeformity

Techniques for Late Surgical Treatment of Acromioclavicular Injuries

Reduction of AC joint and repair of AC and CC ligaments

Resection of distal clavicle and reconstruction of CC ligaments (Weaver-Dunn Procedure)

The Anatomy of the Sternoclavicular Joint

Diarthrodial Joint “Saddle shaped” Poor congruence Intra-articular disc

ligament. Divides SC joint into two separate joint spaces.

Costoclavicular ligament- (rhomboid ligament) Short and strong and consist of an anterior and posterior fasciculus

Interclavicular ligament- Connects the superomedial aspects of each clavicle with the capsular ligaments and the upper sternum

Capsular ligament- Covers the anterior and posterior aspects of the joint and represents thickenings of the joint capsule. The anterior portion of the ligament is heavier and stronger than the posterior portion.

Epiphysis of the Medial ClavicleMedial Physis- Last of the ossification

centers to appear in the body and the last epiphysis to close.

Does not ossify until 18th to 20th yearDoes not unite with the clavicle until the 23rd

to 25th year

Radiographic Techniques for Assessing Sternoclavicular Injuries

40-degree cephalic tilt view

CT scan- Best technique for sternoclavicular joint problems

From Wirth MA and Rockwood CA, JAAOS, 4:268, 1996

Injuries Associated with Sternoclavicular Joint Dislocations

Mediastinal Compression

Pneumothorax Laceration of the

superior vena cavaTracheal erosion

From Wirth MA and Rockwood CA, JAAOS, 4:268, 1996

Treatment of Anterior Sternoclavicular DislocationsNonoperative treatment

Analgesics and immobilizationFunctional outcome usually good

Closed reduction Often not successfulDirect pressure over the medial end of the clavicle may reduce the joint

Treatment of Posterior Sternoclavicular Dislocations

Careful examination of the patient is extremely important to rule out vascular compromise.

Consider CT to rule out mediastinal compression

Attempt closed reduction - it is often successful and remains stable.

Closed Reduction Techniques

Abduction tractionAdduction traction“Towel Clip” - anterior force applied to

clavicle by percutaneously applied towel clip

Operative TechniquesResection arthroplasty

May result in instability of remaining clavicle unless stabilization is done.

Suggest minimal resection of bone and fixation of medial clavicle to first rib.

Sternoclavicular reconstruction with suture, tendon graft.