summary Scapula Fractures are uncommon fractures to the shoulder girdle caused by high energy trauma and associated with pulmonary injury, head injury, and increased injury severity scores. Diagnosis can be made with plain radiographs and CT studies are helpful for fracture characterization and surgical planning. Treatment is usually nonoperative with a sling. Surgical management is indicated for intra-articular fractures, displaced scapular body/neck fractures, open fractures, and those associated with glenohumeral instability. Epidemiology Incidence rare <1% of all fractures 3-5% of shoulder girdle fractures Demographics age commonly between 25-50 males > females Location scapular body/spine = 45-50% glenoid = 35% glenoid neck = 25% glenoid fossa/rim = 10% often associated with impaction of humeral head into glenoid acromion = 8% coracoid = 7% Etiology Pathophysiology mechanism of injury high-energy trauma (80-90%) login to view 2 more bullets indirect trauma through fall on outstretched hand glenohumeral dislocation login to view 4 more bullets Associated injuries (in 80-95%) medical thoracic injury (80%) login to view 2 more bullets head injury (35-50%) orthopaedic rib fractures (53%) ipsilateral extremity injury (50%) login to view 1 more bullet spine fracture (26-30%) pelvic ring/acetabular fractures (15%) login to view 1 more bullet upper extremity vascular injury (11%) login to view 2 more bullets brachial plexus injury (5-13%) login to view 2 more bullets Anatomy Osteology scapular body origin or insertion of 18 muscles login to view 1 more bullet large triangle shape with 4 major processes login to view 27 more bullets Arthrology glenohumeral joint glenoid & labrum support humeral head to produce high degree of motion stability provided by static and dynamic stabilizers scapulothoracic joint not a true joint but does represent an articulation between scapula and thorax involved primarily in elevation and depression of shoulder as well as rotation and pro-/retraction acromioclavicular (AC) joint articulation of acromion and distal clavicle login to view 1 more bullet 8º of rotation occurs through acromioclavicular joint superior shoulder suspensory complex bone & soft tissue ring which provides connection of glenoid/scapula to axial skeleton composed of 4 bony landmarks login to view 4 more bullets also composed of ligamentous complexes of acromioclavicular and coracoclavicular joints Blood supply contributions from anterior and posterior circumflex, scapular circumflex and suprascapular arteries watershed area present in anterosuperior glenoid Nervous system scapula is intimately associated with brachial plexus axillary nerve is at risk inferior to the glenoid as it runs from anterior to posterior compression of suprascapular nerve at scapular notch leads to supraspinatus/infraspinatus weakness, with compression at the spinoglenoid notch leading only to infraspinatus weakness Biomechanics scapula contributes to glenohumeral rotation and abduction 1/3 of shoulder motion is scapulothoracic, 2/3 is glenohumeral Classification Classification is based on the location of the fracture and includes scapular body fractures usually described based on anatomic location scapular neck fractures look for associated AC joint separation or clavicle fracture login to view 1 more bullet glenoid fractures Ideberg classification with Goss modification (below) login to view 1 more bullet AO-OTA classification login to view 1 more bullet acromial fractures Kuhn classification coracoid fractures Ogawa classification - based on fracture proximity to CC ligaments Eyres classification scapulothoracic dissociation Ogawa Coracoid Fracture Classification Type I Fracture occurs proximal to the coracoclavicular ligament Type II Fracture occurs towards the tip of the coracoid Kuhn Acromial Fracture Classification Type I Nondisplaced or minimally displaced Type II Displaced but does not compromise the subacromial space Type III Displaced and compromises the subacromial space Ideberg Classification of Glenoid Fracture Type Ia Anterior rim fracture Type Ib Posterior rim fracture Type II Fracture line through glenoid fossa exiting scapula inferiorly Type III Fracture line through glenoid fossa exiting scapula superiorly Type IV Fracture line through glenoid fossa exiting scapula medially through body Type Va Combination of types II and IV Type Vb Combination of types III and IV Type Vc Combination of types II, III, and IV Type VI Severe comminution AO Classification for Glenoid Fractures Fracture type Subtype Qualification 14F0: Extra-articular Glenoid neck 14F1: Simple, intra-articular 1.1: anterior glenoid rim 1.2: posterior glenoid rim 1.3: transverse/short oblique f: infraequitorial, single quadrant r: supraequatorial, 2 quadrants t: infraequitorial, 2 quadrants i: infraequitorial e: equitorial p: supraequitorial 14F2: Multifragmentary 2.1: >= 3 articular fragments 2.2: central fracture-dislocation 14B: Extension into body 1: exits body at <=2 points 2: exits body at >=3 points presentation History traumatic direct blow to shoulder or fall on outstretched arm scapula fracture may be missed or diagnosed late in presence of other distracting, traumatic injuries Symptoms diffuse, severe shoulder pain systemic symptoms shortness of breath chest wall pain Physical exam inspection tenderness to palpation login to view 5 more bullets evaluate for abnormal shoulder contour compared to contralateral site look for open wounds or abrasions soft tissue swelling may be significant motion acute active range of motion testing not recommended login to view 1 more bullet gentle passive range of motion can be useful in noting any blocks to motion neurovascular check motor and sensory function of nerves at risk login to view 4 more bullets confirm symmetry of extremity pulses to contralateral side Imaging Radiographs recommended views true AP, grashey AP, scapular Y and axillary lateral view AP chest radiograph login to view 3 more bullets measurements intra-articular step-off lateral border offset (medialization) glenopolar angle (measured on grashey AP) login to view 2 more bullets scapular angulation login to view 1 more bullet CT indications intra-articular fracture significant displacement >1cm may also help detect other thoracic/spine injuries views three-dimensional reconstruction better demonstrates fracture patterns coronal and axial views useful to evaluate displacement, intra-articular step-off and medialization of glenoid sagittal view useful to evaluate anterior-posterior displacement and angulation MRI indications not regularly obtained but may be useful in some cases to evaluate the superior shoulder suspensory complex for ligamentous injury differential Os Acromiale unfused secondary ossification centers (meso- and meta-acromion) associated with impingement and rotator cuff symptoms and may be detected incidentally with trauma Treatment Nonoperative sling for 2-3 weeks, followed by early motion scapular body fractures login to view 11 more bullets scapular neck fractures login to view 8 more bullets intra-articular glenoid fractures login to view 5 more bullets acromion fractures login to view 4 more bullets coracoid fractures login to view 5 more bullets Operative open reduction internal fixation indications (most are relative) login to view 27 more bullets techniques login to view 6 more bullets outcomes login to view 12 more bullets Techniques Nonoperative (immobilization) noninvasive but can lead to stiffness technique sling immobilization for 2-3 weeks Open Reduction Internal Fixation (ORIF) scapular body/neck fractures approaches login to view 9 more bullets technique login to view 3 more bullets complications login to view 3 more bullets intra-articular glenoid fractures approaches login to view 11 more bullets techniques login to view 7 more bullets complications login to view 4 more bullets acromion fractures approach login to view 2 more bullets technique login to view 7 more bullets complications login to view 1 more bullet coracoid fractures approach login to view 2 more bullets technique login to view 6 more bullets complications login to view 2 more bullets complications Post-traumatic glenohumeral arthritis risk factors intra-articular glenoid fracture with residual step-off/displacement treatment conservative management login to view 1 more bullet shoulder arthroplasty (total vs. reverse) Malunion risk factors higher degree of angulation, translation or medialization more likely with nonoperative management login to view 1 more bullet treatment typically nonoperative depending on location of fracture and degree of deformity If deformity involves glenoid, may be correctable with reverse total shoulder arthroplasty Recurrent glenohumeral instability risk factors younger patients larger degree of bone loss (anterior or posterior) treatment bony fixation (open or percutaneous) arthroscopic vs. open suture anchor repair with labral advancement login to view 1 more bullet Neurovascular injury risk factors scapulothoracic dissociation iatrogenic injury during surgical dissection login to view 8 more bullets treatment nerve injury after scapulothoracic dissociation login to view 1 more bullet iatrogenic neurovascular injury login to view 1 more bullet