SUMMARY

• Distal Humerus Fractures are traumatic injuries to the elbow that comprise of supracondylar fractures, single column fractures, column fractures or coronal shear fractures.

• Diagnosis is made with plain radiographs of the humerus and elbow. CT scan is helpful for intra-articular assessment and operative planning. 

• Treatment is usually open reduction and internal fixation. 

EPIDEMIOLOGY

• Incidence

  • accounts for 2% of all fractures

  • accounts for 30% of elbow fractures

  • incidence has been steadily increasing

• Demographics

  • most common in young males and older females

• Anatomic location

  • distal intercondylar fractures are the most common fracture pattern

ETIOLOGY

• Pathophysiology

  • distal humerus fractures are traumatic injuries that include

    • supracondylar fractures

    • single column (condyle) fractures

    • bicolumnar fractures

    • coronal shear fractures

  • mechanism

    • low energy falls in elderly

    • high energy impact in younger population

  • pathoanatomy

    • elbow position affects fracture type

      • elbow flexed < 90°

        • axial load leads to transcolumnar fracture

        • direct posterior blow leads to olecranon fracture with or without distal humerus involvement

      • elbow flexed > 90°

        • may lead to intercondylar fracture

• Associated injuries

  • elbow dislocation 

  • terrible triad injury 

  • floating elbow

  • Volkmann contracture

    • results from missed forearm compartment syndrome

ANATOMY

• Osteology

  • elbow is a hinged joint

  • articular surface is in

    • 6 degrees of valgus

    • 5 degrees of external rotation

    • 30 degrees of flexion

  • trochlea

    • articulates with sigmoid notch

    • allows for flexion and extension

  • capitellum

    • articulates with proximal radius

    • allows for forearm rotation

• Muscles

  • common flexors (originate from medial epicondyle)

    • pronator teres 

    • flexor carpi radialis 

    • palmaris longus 

    • FDS 

    • FCU 

  • common extensors (originate from lateral epicondyle)

    • anconeus 

    • ECRL 

    • ECRB 

    • extensor digitorum comminus 

    • EDM 

    • ECU 

• Ligaments

  • medial collateral ligament

    • anterior bundle originates from distal medial epicondyle

    • inserts on sublime tubercle

    • primary restraint to valgus stress at the elbow from 30-120°

    • tight in pronation

  • lateral collateral ligament

    • originates from distal lateral epicondyle

    • inserts on crista supinatorus

    • stabilizer against posterolateral rotational instability

    • tight in supination

• Nerves

  • ulnar nerve

    • resides in the cubital tunnel in a subcutaneous position posterior to the medial condyle

  • radial nerve 

     

    • anatomic landmarks

      • in the spiral groove 15cm proximal to distal humeral articular surface

      • 10cm from the medial edge of the olecranon

      • 7.5cm from the lateral edge of the olecranon

      • 3.9 cm (two finger-breadths) proximal to the triceps aponeurosis

    • runs between brachioradialis and brachialis proximal to elbow

    • divides into PIN and superficial radial nerve at the level of the radial head

• Blood supply

  • intraosseous and extraosseous blood supplies that may be compromised by the injury

CLASSIFICATION

• Can be classified as

  • supracondylar fractures

  • distal single column fractures 

    • 5% of fractures

    • subclassified using Milch classification system (see table)

    • lateral condyle more common than medial

  • distal bicolumnar fractures

    • classified using Jupiter classification system (see table)

    • 5 major articular fragments have been identified

      • capitellum/lateral trochlea

      • lateral epicondyle

      • posterolateral epicondyle

      • posterior trochlea

      • medial trochlea/epicondyle

• AO/OTA Classification of Distal Humerus Fractures
  Type A	Extra-articular (supracondylar fracture), 80% are extension type; epicondyle
  Type B	Intraarticular- Single column (partial articular-isolated condylar, coronal shear, epicondyle with articular extension).
  Type C	Intraarticular- Both columns fractured and no portion of the joint is contiguous with the shaft (complete articular)
  	Each type further divided by degree and location of fracture comminution

• Milch Classification of Single Column Condyle Fractures
  Milch Type I	Lateral trochlear ridge intact
  Milch Type II	Fracture through lateral trochlear ridge

• Jupiter Classification of Two-Column Distal Humerus Fractures
  High-T	Transverse fx proximal to or at upper olecranon fossa
  Low-T	Transverse fx just proximal to trochlea (common)
  Y	Oblique fx line through both columns with distal vertical fx line
  H	Trochlea is a free fragment (risk of AVN)
  Medial lambda	Proximal fx line exists medially
  Lateral lambda	Proximal fx line exists laterally
  Multiplane T (not pictured)	T type with an additional fracture in coronal plane

PRESENTATION

• Symptoms

  • elbow pain and swelling

• Physical exam

  • check for open wounds, especially posteriorly

  • gross instability often present

    • avoid ROM due to risk of neurovascular damage

  • neurovascular exam

    • check function of radial, ulnar, and median nerves

    • check distal pulses

      • brachial artery may be injured

      • if pulse decreased, obtain noninvasive vascular studies and consult vascular surgery if abnormal

  • monitor carefully for forearm compartment syndrome

IMAGING

• Radiographs

  • recommended views

    • AP

      • ideally taken with 40 deg of flexion

    • lateral

  • additional views

    • humerus and forearm radiographs

    • wrist radiographs

      • obtain if elbow injury present or distal tenderness on exam

    • oblique radiographs 

      • specifically used to evaluate if there is continuity of the trochlear fragment with the medial epicondylar fragment, this can influence hardware choice

    •  traction radiograph

      • may assist with surgical planning

• CT

  • indications

    • often obtained for surgical planning

      • especially helpful when shear fractures of the capitellum and trochlea are suspected

• MRI

  • indications

    • usually not indicated in acute injury

TREATMENT

• Nonoperative

  • cast immobilization

    • indications

      • nondisplaced Milch Type I fractures

    • technique

      • above elbow cast with close follow-up due to risk of displacement

  • short period of immobilization and followed by early range of motion ("bag of bones" technique)

    • indications

      • elderly patients  

        • with significant medical comorbidities precluding surgery

        • unable to comply with postoperative protocol

• Operative

  • closed reduction percutaneous pinning (CRPP)

    • indications

      • displaced Mich Type I fractures

  • open reduction internal fixation (ORIF)

    • indications

      • supracondylar fractures

      • intercondylar / bicolumnar fractures

      • Milch Type II fractures

  • total elbow arthroplasty

    • indications

      • distal comminuted bicolumnar fractures in low demand elderly patients 

         

        • must be able to comply with weightbearing restriction

TECHNIQUES

• Cast Immobilization

  • technique

    • immobilize in supination for lateral condyle fractures

    • immobilize in pronation for medial condyle fractures

• Open reduction internal fixation (ORIF)

  • approach

    • posterior superficial approach 

  • exposures

    • triceps-splitting (Campbell) 

      • technique

        • split triceps tendon in midline down to olecranon

      • for open fractures, approach using the defect leads to better results than an osteotomy

    • triceps-sparing (paratricipital, Alonso-Llames, medial and lateral windows) 

      • indications

        • extra-articular fractures

        • fractures with a simple articular split

      • technique

        • elevate triceps from the humerus using medial and lateral windows

        • can be converted to olecranon osteotomy if needed

    • olecranon osteotomy 

      • indications 

         

        • complex intra-articular fractures

        • fractures with a coronal splint

      • contraindications

        • total elbow arthroplasty is planned/may be required

      • technique

        • perform chevron (apex distal) osteotomy 

           

        • fixation of osteotomy performed using a combination of screws, K wires, tension band or plate

      • complications

        • AIN nerve injury

          • check ability to flex thumb interphalangeal joint in recovery 

             

        • symptomatic hardware (6-30%) 

        • osteotomy nonunion (0-9%)

    • triceps-reflecting (Bryan-Morrey) 

      • technique

        • reflect triceps tendon, forearm fascia, and periosteum off the olecranon from medial to lateral

        • repair through transosseous drill holes

        • immobilize to protect triceps repair for 4-6 weeks postoperatively

    • triceps-reflecting anconeus pedicle (O'Driscoll) 

      • technique

        • elevate anconeous subperiosteally from proximal ulna

    • lateral muscles interval

      • technique

        • elevate the ECRB and part of the ECRL off of the supracondylar ridge

  • fixation

    • perform provisional reduction with k-wires

      • if metaphyseal injury is not comminuted, reducing one column to the metaphysis first may be beneficial

    • perform fixation of articular fragments with countersunk/headless screws

      • consider using positional screws when reducing trochlea to avoid narrowing it with compression

    • perform fixation of condyles and epitrochlear ridge

      • fix the lateral epicondyle using a tension band wire or plate

      • fix the articular segment to the shaft using two plates in orthogonal planes

        • new literature supports parallel plates for increased biomechanics strength 

           

        • no difference in clinical outcomes between 90-90 and parallel plating

      • if the ulnar nerve contacts medial hardware during flexion/extension, can perform an ulnar nerve transposition

        • no difference between rates of post-operative ulnar neuritis with in situ release compared to transposition  

        • no difference in patient-reported outcomes between transposition and in-situ release 

           

    • locking plates are preferred for poor bone quality or comminution 

  • postoperative

    • splint elbow in 70° of flexion

    • remove splint within 7-10 days post-operatively and initiate ROM exercises

      • if osteotomy performed

        • active and active-assisted flexion and extension for 6 weeks

        • no active extension against gravity or resistance

        • no restrictions to rotation

      • if osteotomy not performed

        • active motion against gravity without restrictions

        • no restrictions to rotation

    • start gentle strengthening program at 6 weeks and full strengthening program at 3 months

• Semiconstrained Total Elbow Arthroplasty 

  • indications

    • comminuted articular fractures in osteoporotic bone 

    • inflammatory conditions (e.g. RA)

  • complications specific to this treatment

    • activity restrictions (e.g. can not lift more than 10 pounds) 

       

    • implant loosening

    • polyethylene wear

    • periprosthetic fracture

  • functional outcomes similar to salvage arthroplasty following failed ORIF 

     

COMPLICATIONS

• Elbow stiffness 

   

  • most common (3-42%)

  • mean arc of motion is 90-106 degrees

  • treatment

    • static-progressive splinting

• Heterotopic ossification

  • seen in 8%

  • routine prophylaxis is not warranted due to increased rate of nonunion in patients treated with indomethacin

  • risk factors

    • head injury

    • floating elbow injury

    • Type A and B fractures

    • delayed surgical fixation

• Nonunion 

   

  • low incidence (0-11%)

  • risk factors

    • excessive soft-tissue stripping

    • open fractures

    • comminution 

    • low transcondylar or intercondylar fractures

  • treatment

    • revision ORIF with bone graft

• Malunion

  • avoided by proper surgical technique

    • cubitus valgus (lateral column fractures)

    • cubitus varus (medial column fractures)

• Anterior interosseous nerve injury

  • can be seen with olecranon osteotomy 

• Ulnar nerve injury (10-38%)

  • Postoperative ulnar nerve palsies are most often secondary due to traction during open reduction and internal fixation

• Wound complications (up to 16%)

  • due to poor soft tissue envelope over posterior elbow

• Infection 

  • occurs in 0-14% of patients

• Posttraumatic Arthritis

PROGNOSIS

• ORIF

  • majority of patients regain 75% of elbow motion and strength

    • goal is to restore elbow ROM 30-130° of flexion

• Total elbow arthroplasty

  • has rates of implant survival >75% at 10 years if used with appropriate indications 

  • expected ROM is 26-125 degrees

  • in patients > 65 years old functional outcomes were higher with TEA than ORIF at 2-year follow-up

• "Bag of bones" 

  • goal is a painless pseudoarthrosis

  • only fair functional outcomes

  • high rate of nonunion and later surgery

• Unsatisfactory outcomes in up to 25%

  • treatment of these fractures is complex due to

    • low fracture line of one or both columns

    • metaphyseal fragmentation of one or both columns

    • articular comminution

    • poor bone quality