Summary Midshaft Clavicle fractures are common traumatic injuries caused by a direct impact to the shoulder girdle and is most commonly seen in young, active adults. Diagnosis can be made radiographically with AP and cephalic tilt clavicle x-rays. Treatment is nonoperative or operative based on patient activity and demands, along with degree of displacement, shortening, and comminution. Epidemiology Incidence common incidence 1 in 1000 people per year prevalence clavicle fractures account for 2.6-4% of all adult fractures Demographics often seen in young, active patients most common in males < 30 years old Location 75-80% of all clavicle fractures will occur in the middle third segment Etiology Pathophysiology mechanism of injury fall onto lateral aspect of shoulder (85%) direct impact to clavicle pathoanatomy junction of the outer and middle third is the thinnest part of the bone prone to fracture with axial loading only area not protected by or reinforced with muscle and ligamentous attachments displaced fractures medial fragment pulled posterosuperiorly by sternocleidomastoid muscle lateral fragment pulled inferomedially by pectoralis major and and weight of arm open fractures usually result from medial fragment "buttonholing" through platysma Associated conditions medical pneumothorax closed head injury orthopedic ipsilateral scapular fracture (floating shoulder) scapulothoracic dissociation traction injury significantly distracted/widened fracture fragments widened interval between scapula and spine brachial plexus or vascular injury rib fracture neurovascular injury ANATOMY Osteology Shape S-shaped bone flat laterally, tubular centrally, and prismatic medially Articulations sternoclavicular joint four primary stabilizers posterior capsular ligament anterior sternoclavicular ligament costoclavicular ligament intra-articular disc acromioclavicular joint two primary stabilizers coracoclavicular ligament acromioclavicular ligament Muscles sternocleidomastoid pulls medial segment proximally clavicular head originates superiorly on medial third inserts on mastoid process deltoid stabilizes distal clavicle and assists with shoulder abduction shortening of clavicle decreases lever arm of deltoid originates from anterior lateral third clavicle, acromion, and scapular spine inserts on deltoid tuberosity trapezius originates from occiput and C-T spine spinous process inserts on lateral posterosuperior third of clavicle, acromion, and scapular spine pectoralis major pulls medially causing shortening clavicular head originates from anteroinferior surface of medial half of clavicle inserts on crest of greater tubercle of humerus, lateral to bicipital groove subclavius protects NV structures which pass deep to muscle and displace clavicle inferiorly originates from 1st rib and costal cartilage inserts on undersurface of clavicle sternohyoid originates on sternal end of clavicle inserts on hyoid bone platysma violated with skin tenting originates from pectoral fascia inserts mandible Ligaments coracoclavicular (CC) ligaments provide superior/inferior stability to AC joint two components trapezoid (lateral) inserts 3 cm medial to distal clavicle conoid (medial) inserts 4.5 cm medial to distal clavicle Blood Supply subclavian vessel passes posterior and underneath clavicle near junction of medial and middle third subclavian vein closest to clavicle and anterior to artery and plexus Nervous System supraclavicular nerves cutaneous nerves that run vertically over clavicle and supply superior chest wall brachial plexus Biomechanics middle third is weakest portion of clavicle thinnest and narrowest transitional of the bone in both curvature and in cross-sectional anatomy only area not supported by ligamentous or muscular attachments Classification Neer Classification (simple) Nondisplaced < 100% displacement Nonoperative Displaced > 100% displacement Operative AO classification Type A = Simple A1 = spiral A2 = oblique A3 = transverse Nonoperative vs. operative Type B = Wedge B1 = spiral wedge B2 = bending wedge B3 = fragmented wedge Nonoperative vs. operative Type C = Complex C1 = complex spiral C2 = segmental C3 = irregular Operative Presentation History popping or cracking sound near shoulder after fall Symptoms acute onset of anterior shoulder pain or directly over clavicle Physical exam inspection tender, swelling, crepitus and deformity over clavicle skin tenting (impending open fracture) neurovascular exam assess subclavian vessels and brachial plexus Imaging Radiographs recommended views clavicle series upright AP clavicle supine may underappeciate displacement with gravity eliminated 15° cephalic tilt (zanca view) eliminates overlapping scapula shoulder series evaluate for other injuries (ie proximal humerus, scapula) optional views upright chest x-ray compare shortening with contralateral side evaluate for pneumothorax findings superior displacement of medial fragment inferior displacement of lateral fragment shortening measurements shortening two methods AP clavicle - distance between the corresponding ends of the medial and lateral fragments AP chest - direct comparison of length of clavicle to the contralateral side shortening >2cm associated with decrease shoulder strength and endurance displacement displacement relative to width of clavicle (percent) >100% displacement is a risk factor for nonunion CT indications assess fracture pattern for preop planning comminution, shortening, articular extension, nonunion vascular injury medial clavicle fracture SC joint dislocation views axial, coronal and 3D reconstruction most useful with contrast if concern for vascular injury Differential Adult distal third clavicle fx older, osteoporotic patient x-ray may show increased CC distance Sternoclavicular dislocation high energy mechanism may present with dysphagia, stridor, asymmetric pulses, paresthesias due to compression of surrounding structures serendipity view or CT best demonstrate displacement Acromioclavicular Joint Injury pain and prominence more lateral over AC joint zanca or axillary views shows displaced distal clavicle relative to acromion Treatment Nonoperative sling immobilization indications < 2cm shortening and displacement < 1cm displacement of the superior shoulder suspensory complex closed and no neurovascular injury low demand patient techniques sling figure-of-8 strap elevate and extend shoulder to bring distal fragment to the proximal fragment outcomes figure-of-8 associated with more pain, shortening, and lower compliance than sling no difference in functional or cosmetic outcomes between sling and figure-of-eight braces Operative open reduction internal fixation (ORIF) indications absolute open fractures displaced fracture with skin tenting subclavian artery or vein injury floating shoulder (clavicle and scapular neck fracture) relative and controversial indications displaced with > 2cm shortening bilateral displaced clavicle fractures brachial plexus injury (questionable because 66% have spontaneous return) closed head injury seizure disorder polytrauma patient techniques intramedullary fixation open reduction internal fixation with plate and screws outcomes operative fixation has higher union rate (>94%) similar or better functional outcomes than nonoperative faster time to union - operative (16.4 weeks) vs. non-operative (28.4 weeks) Techniques Sling Immobilization technique immobilize using sling or figure-of-eight brace no attempt at reduction should be made rehab gentle passive ROM exercises at 2 weeks strengthening exercises begin at 6 weeks return to sports at 4-6 months advantage overall good outcomes avoid surgical/hardware complications disadvantage higher nonunion rate compared to operative management slower time to union complications nonunion (10-15%) malunion poor cosmesis decreased shoulder strength and endurance displaced midshaft clavicle fractures healed with > 2cm of shortening Plate Fixation approach beach chair vs. supine direct superior vs. anterior incision technique plate configuration anterior plating superior plating (compared to anterior plating) higher load to failure increased plate strength with inferior bone comminution increased risk of neuromuscular injury decreased removal of deltoid attachment dual plating low rate of symptomatic hardware removal (0-3.7%) biomechanically equivalent or superior to single 3.5mm plate plate options limited contact, pre-controured, 3.5mm dynamic compression plate 3.5mm reconstruction plate 2.0mm, 2.4mm and 2.7mm plates can be used and combined for dual plating advantages improved results with ORIF for clavicle fractures with > 2cm shortening and > 100% displacement improved functional outcomes/less pain with overhead activity faster time to union decreased symptomatic nonunion and malunion rate improved cosmetic satisfaction improved overall shoulder satisfaction increased shoulder strength and endurance disadvantage increased risk of need for future procedures implant removal debridement for infection complications hardware irritation infection neurovascular injury supraclavicular nerve injury hardware failure pneumothorax postoperative Rehabilitation early sling for 7-10 days followed by active motion late strengthening at ~6 weeks when pain-free motion and radiographic evidence of union full activity including sports at ~3 months Intramedullary Fixation (IMN) technique positioning beach chair or supine approach percutaneous or mini-open implant choices intramedullary nail goal size of intramedullary nail is 30-40% of midshaft diameter cannulated screws titanium elastic nail Hagle pin advantages smaller incision less soft-tissue disruption avoids supraclavicular nerves that are commonly injured with plating best for simple patterns disadvantages higher complication rate hardware migration, implant irritation, secondary procedures biomechanically inferior to plating unable to lock and control rotation typically requires hardware removal at 6 months contraindications substantial comminution segmental fractures complications hardware migration loss of reduction Complications Nonoperative treatment nonunion (~15%) risk factors fracture comminution (Z deformity) fracture displacement female gender advanced age smoker predictors at 6 week motion at fracture site, no callus on x-ray, DASH >40 0 - 3% nonunion 2 or 3 - 60% nonunion treatment if asymptomatic, no treatment necessary if symptomatic, ORIF with plate and bone graft (particularly atrophic nonunion) malunion (~20%) definition shortening > 3cm angulation > 30° translation > 1cm presentation pain and increased fatigue with overhead activities thoracic outlet syndrome dissatisfaction with appearance difficulty with shoulder straps and backpacks treatment clavicle osteotomy with bone grafting, if symptomatic Operative treatment hardware prominence 8-30% of patient request plate removal superior plates associated with increased irritation neurovascular injury superior plates associated with increased risk of subclavian artery or vein penetration subclavian thrombosis supraclavicular nerve injury most common complication 83% incidence of numbness noted at 2 weeks postop can improve over time with ~50% having persistent numbness at 1 year nonunion (1-5%) infection (~4.8%) risk factors illicit drug use diabetes previous shoulder surgery mechanical failure (~1.4%) pneumothorax adhesive capsulitis 4% in surgical group develop adhesive capsulitis requiring surgical intervention