Summary Proximal Humerus Fractures are relatively common physeal and metaphyseal fractures of the proximal humerus. Diagnosis is confirmed with plain radiographs of the shoulder. Treatment is usually nonoperative in younger patients due to the remodeling potential of the proximal humerus. Operative management is indicated for significant displacement in older children with minimal physeal growth remaining. Epidemiology Incidence < 5% of fractures in children Demographics most common in adolescents (peak age at 15 years), but may occur in younger patients Anatomical location Salter-Harris classification SH-I is most frequent in <5 year olds SH-II is most frequent in >12 year olds metaphyseal fractures typically occur in 5 to 12 year olds Etiology Pathophysiology mechanism of injury blunt trauma indirect trauma pathoanatomy of physeal fractures proximal fragment (epiphysis) displacement abducted and externally rotated due to rotator cuff muscles distal fragment (shaft) displacement anterior, adducted and shortened due to pectoralis major and deltoid muscles Anatomy Radiographic appearance of secondary ossification centers proximal humeral epiphysis at 6 mos greater tuberosity appears at 1-3 yrs lesser tuberosity appears at 4-5 yrs Growth proximal humerus physis closes at 14-17 in girls, 16-18 in boys 80% of humerus growth comes from the proximal physis highest proximal:distal ratio difference (femur is second with 30:70 proximal:distal ratio) Contributes to high remodeling potential Classification Neer-Horowitz Classification Type I Minimally displaced (<5mm) Type II Displaced < 1/3 of shaft width Type III Displaced greater than 1/3 and less than 2/3 of shaft width Type IV Displaced greater than 2/3 of shaft width Presentation History identify mechanism Symptoms shoulder pain deformity ecchymosis Physical exam inspection of skin motion and tenderness of neck evaluate ipsilateral sternoclavicular joint and elbow neurovascular examination check brachial plexus nerve function perform vascular examination of arm Imaging Radiographs standard views AP lateral axillary view (or scapula Y) optional contralateral shoulder for comparison views bone age (rarely required) findings assess maximum angulation of fracture displacement glenohumeral dislocation (very rare with associated fracture) Ultrasound ultrasound may be neccessary in newborns before secondary ossification centers are formed Differential Little Leaguer's shoulder an overuse injury in throwers that may demonstrate mild physeal widening and metaphyseal changes not an actual fracture Pathologic fracture ABC UBC Diagnosis Radiographic diagnosis confirmed by history, physical exam, and radiographs Treatment Nonoperative immobilization indications acceptable alignment for non-operative management <10 years old = any degree of angulation 10-12 years old = up to 60-75° of angulation >12 years old = up to 45° of angulation or 2/3 displacement technique immobilization modalities sling +/- swathe shoulder immobilizer coaptation splint Operative closed reduction +/- fixation indications unacceptable alignment for non-operative management as described above open reduction internal fixation indications unable to obtain acceptable reduction due to soft tissue interposition long head of biceps tendon (most common) joint capsule infolded periosteum deltoid muscle open fractures fractures associated with vascular injuries intra-articular displacement Techniques Closed reduction ± fixation reduction maneuver longitudinal traction shoulder abduction to 90 degrees external rotation fixation options percutaneous pinning two or three lateral threaded pins starting point must consider branches of axillary nerve (lateral) and musculocutaneous nerve (anterior) ideally separated at fracture retrograde elastic nails Cannulated screws in older patients Open reduction with fixation approach deltopectoral interval fixation methods as above Complications Loss of reduction risk factors unstable fractures treated with closed reduction without pinning Axillary nerve Injuries occur in <1% of case due to injury alone typically are neuropraxias associated with a medially displaced shaft higher risk with percutaneous pinning place lateral pin distal to the axillary nerve, which is approximately 5 cm from the acromion in adult patients and propotionally less in smaller patients, or twice the distance from the superior aspect of the humeral head to the inferiormost margin of the humeral head Malunion severe varus malalignment may cause glenohumeral impingement Limb-length inequality fracture shortening <3 cm usually well tolerated in patients < 12 years of age growth arrest rare Hypertrophic scar deltopectoral approach with open reduction and fixation Pin site infection incidence 5-22% Prognosis Excellent abundant remodeling potential of the proximal humerus, particularly in younger patients due to range of motion of the shoulder joint