Proximal Humerus Fractures - Trauma (2024)

• common

  • 4-6% of all fractures

  • third most common non-vertebral fracture pattern seen in the elderly (>65 years old)

• two-part surgical neck fractures are most common

• 2:1 female to male ratio

• increasing age associated with more complex fracture types

• may occur at the surgical neck, anatomic neck, greater tuberosity, and lesser tuberosity

  • two-part surgical neck fractures are most common

• osteoporosis

• diabetes

• epilepsy

• female gender

• mechanism

  • low-energy falls

    • elderly with osteoporotic bone

  • high-energy trauma

    • young individuals

    • concomitant soft tissue and neurovascular injuries

• pathoanatomy

  • vascularity of articular segment is more likely to be preserved if ≥ 8mm of calcar is attached to articular segment

    • predictors of humeral head ischemia (Hertel criteria)

      • <8 mm of calcar length attached to articular segment

      • disrupted medial hinge

      • increasing fracture complexity

      • displacement >10mm

      • angulation >45°

    • predictors of humeral head ischemia does not necessarily predict subsequent avascular necrosis

• nerve injury

  • axillary nerve injury most common

• arterial injury

  • uncommon (incidence 5-6%), higher likelihood in older patients

  • most often occur at level of surgical neck or with subcoracoid dislocation of the head

• anatomic neck

  • represents the old epiphyseal plate

• surgical neck

  • represents the weakened area below head

  • more often involved in fractures than anatomic neck

• average neck-shaft angle is 135 degrees

• pectoralis major displaces shaft anteriorly and medially

• deltoid displaces proximal fragment laterally

• supraspinatus, infraspinatus, and teres minor externally rotate greater tuberosity

• subscapularis internally rotates articular segment or lesser tuberosity

• Coracohumeral ligament

  • attaches to coracoid and greater tuberosity and strengthens the rotator interval

• SGHL

  • restraint to inferior translation at 0° degrees of abduction (neutral rotation)

• MGHL

  • resists AP translation in the midrange (~45°) of abduction

• IGHL

  • restraint to AP translation at 90° degrees of abduction

• anterior humeral circumflex artery

  • large number ofanastomosiswith other vessels in the proximal humerus

  • branches

    • anterolateral ascending branch

      • arcuate artery is the terminal branch and main supply to greater tuberosity

• posterior humeral circumflex artery

  • recent studies suggest it is the main blood supply to humeral head

    See Also

    Distal Humerus Fractures - TraumaFractures of the Distal HumerusDistal Humerus Fractures of the Elbow - OrthoInfo - AAOST-Intercondylar Distal Humerus Fracture

AO/OTA

• organizes fractures into 3 main groups and additional subgroups based on

  • fracture location

  • status of the surgical neck

  • presence/absence of dislocation

Neer classification

• based on anatomic relationship of 4 segments

  • greater tuberosity

  • lesser tuberosity

  • articular surface

  • shaft

• considered a separate part if

  • displacement of > 1 cm

  • 45° angulation

• pain and swelling

• decreased motion

• inspection

  • extensive ecchymosis of chest, arm, and forearm

• neurovascular exam

  • axillary nerve injury most common

    • determine function of deltoid muscle and lateral shoulder sensation

  • arterial injury may be masked by extensive collateral circulation preserving distal pulses

• examine for concomitant chest wall injuries

• recommended views

  • complete trauma series

    • true AP (Grashey)

    • scapular Y

    • axillary

  • additional views

    • apical oblique

    • Velpeau

    • West Point axillary

  • findings

    • combined cortical thickness (medial + lateral thickness >4 mm)

      • studies suggest correlation with increased lateral plate pullout strength

    • pseudosubluxation (inferior humeral head subluxation) caused by blood in the capsule and muscular atony

• indications

  • preoperative planning

  • humeral head or greater tuberosity position uncertain

  • intra-articular comminution

  • concern for head-split fracture

• indications

  • rarely indicated

  • useful to identify associated rotator cuff injury

• sling immobilization followed by progressive rehabilitation

  • indications

    • most proximal humerus fractures can be treated nonoperatively including

      • minimally displaced surgical and anatomic neck fractures

      • greater tuberosity fracture displaced < 5mm

        • >5mm displacement will result in impingement with loss of abduction and external rotation

      • fractures in patients who are not surgical candidates

    • additional variables to consider

      • age

      • fracture type

      • fracture displacement

      • bone quality

      • dominance

      • general medical condition

      • concurrent injuries

  • outcomes

    • immediate physical therapy results in faster recover

• closed reduction percutaneous pinning (CRPP)

  • indications

    • 2-part surgical neck fractures

    • 3-part and valgus-impacted 4-part fractures in patients with good bone quality, minimal metaphyseal comminution, and intact medial calcar

  • outcomes

    • considerably higher complication rate compared to ORIF, HA, and RSA

      • axillary nerve at risk with lateral pins

      • musculocutaneous nerve, cephalic vein, and bicep tendon at risk with anterior pins

      See Also

      Distal Humeral fractures

• ORIF

  • indications

    • greater tuberosity displaced > 5mm

    • displaced 2-part fractures

    • 3-, and 4-part fractures in younger patients

    • head-splitting fractures in younger patients

  • outcomes

    • medial support necessary for fractures with posteromedial comminution

      • consider use of a fibula strut if concerned about medial support or bone quality

    • calcar screw placement critical to decrease varus collapse of head

• Intramedullary nailing

  • indications

    • surgical neck fractures or 3-part greater tuberosity fractures in younger patients

    • combined proximal humerus and humeral shaft fractures

  • outcomes

    • biomechanically inferior with torsional stress compared to plates

    • favorable rates of fracture healing and ROM compared to ORIF

• Arthroplasty

  • indications

    • hemiarthroplasty

      • in younger patients (40-65 years old) with complex fracture-dislocations or head-splitting components that may fail fixation

      • recommended use of convertible stems to permit easier conversion to RSA if necessary in future

    • reverse total shoulder

      • low-demand elderly individuals with non-reconstructible tuberosities and poor bone stock

      • older patients with fracture-dislocation

      • reverse total shoulder arthroplasty following failed nonoperative management is associated with better functional outcomes than reverse total shoulder arthroplasty following failed open reduction and internal fixation

  • outcomes

    • improved results if

      • anatomic tuberosity reduction and healing

      • restoration of humeral height and version

        • humeral height is best judged from the superior border of the pectoralis major insertion

    • poor results with

      • tuberosity nonunion or malunion

      • retroversion of humeral component > 40°

• technique

  • sling for comfort x2-3wks, immediate physical therapy for early ROM

CRPP (closed reduction percutaneous pinning)

• approach

  • percutaneous

• technique

  • use threaded pins but do not cross cartilage

  • externally rotate shoulder during pin placement

  • engage cortex 2 cm inferior to inferior border of humeral head

• complications

  • with lateral pins

    • risk of injury to axillary nerve

  • with anterior pins

    • risk of injury to biceps tendon, musculocutaneous n., cephalic vein

  • possible pin migration

ORIF

• approach

  • anterior (deltopectoral)

  • lateral (deltoid-splitting)

    • increased risk of axillary nerve injury

• technique

  • heavy nonabsorbable sutures

    • figure-of-8 technique should be used for isolated greater tuberosity fx reduction and fixation (avoid hardware due to impingement)

  • isolated screw

    • may be used for greater tuberosity fx reduction and fixation in young patients with good bone stock

  • locking plate

    • screw cut-out (up to 14%) is the most common complication following ORIF with a periarticular locking plates

    • more elastic than blade plate making it a better option in osteoporotic bone

    • place plate lateral to the bicipital groove and pectoralis major tendon to avoid injury to the ascending branch of anterior humeral circumflex artery

    • placement of an inferomedial calcar screw(s) can prevent postoperative varus collapse, especially in osteoporotic bone

• postoperative Rehabilitation

  • important part of management

  • best results with guided protocols (3-phase programs)

    • early passive ROM

    • active ROM and progressive resistance

    • advanced stretching and strengthening program

  • prolonged immobilization leads to stiffness

Intramedullary nailing

• approach

  • superior deltoid-splitting approach

• technique

  • lock nail with trauma or pathologic fractures

  • straight nails are placed through the superior articular cartilage (more central entry point)

  • nails with proximal bend are placed through an entry point just medial to rotator cuff insertion

• complications

  • rod migration in older patients with osteoporotic bone is a concern

  • shoulder pain from violating rotator cuff

  • nerve injury with interlocking screw placement

    • radial nerve at risk with lateral to medial distal screw

    • musculocutaneous nerve at risk with anterior to posterior distal screw

Hemiarthroplasty

• approach

  • anterior (deltopectoral)

• technique for fractures

  • cerclage wire or suture passed through hole in prosthesis and tuberosities improves fracture stability

  • place greater tuberosity ~8 mm below articular surface of humeral head (HTD = head to tuberosity distance)

    • nonanatomic placement of tuberosities results in impairment in external rotation kinematics with an 8-fold increase in torque requirements

  • height of the prosthesis best determined off the superior edge of the pectoralis major tendon

    • 5.6cm between top of humeral head and superior edge of tendon

  • post-operative passive external rotation places the most stress on the lesser tuberosity fragment

Reverse shoulder arthroplasty

• approach

  • anterior (deltopectoral)

  • anterolateral deltoid split

• technique for fractures

  • ensure adequate glenoid bone stock

  • ensure functioning deltoid muscle

  • repair of the greater tuberosity is always recommended despite ability of RSA design to compensate for non-functioning tuberosities/rotator cuff

    • improves range of motion

Screw cut-out

• incidence

  • most common complication following periarticular locking plating fixation (up to 14%)

Avascular necrosis

• risk factors

  • risk factors for humeral head ischemia are not the same for developing subsequent avascular necrosis

    • better tolerated than in lower extremity

    • no relationship to type of fixation (plate or cerclage wires)

• incidence

  • axillary nerve injury most common (up to 58% with studies using EMG)

    • increased risk with lateral (deltoid-splitting) approach

    • axillary nerve is usually found ~5-7cm distal to the tip of the acromion

    • at risk with lateral pins in CRPP

  • suprascapular nerve (up to 48%)

  • musculocutaneous nerve

    • at risk with anterior pins in CRPP

Malunion

• usually varus apex-anterior or malunion of GT

• results inferior if converting from varus malunited fracture to TSA

  • use reverse shoulder arthroplasty instead

Nonunion

• most common after two-part surgical neck fracture

• treatment of chronic nonunion/malunion in the elderly should include arthroplasty

• lesser tuberosity nonunion leads to weakness with lift-off testing

• greater tuberosity nonunion after arthroplasty leads to lack of external rotation and, to a lesser degree, active shoulder elevation

• greatest risk factors for nonunion are age and smoking

Long head of biceps tendon injuries

• also at risk with anterior pin in CRPP

• consider in all patients with lesser tuberosity fracture

Adhesive capsulitis and scar tissue