Humeral Shaft Fractures

Question 1

Epidemiology

Answer 1

Incidence

• 3-5% of all fractures
• bimodal age distribution
  
  • young patients with high-energy trauma
  • elderly, osteopenic patients with low-energy injuries

Question 2

Classification

Answer 2

1. OTA
2. Descriptive

• fracture location: proximal, middle or distal third
• fracture pattern: spiral, transverse, comminuted

Question 3

Holstein-Lewis fracture

Answer 3

a spiral fracture of the distal one-third of the humeral shaft commonly associated with neuropraxia of the radial nerve (22% incidence)

Question 4

Physical exam

Answer 4

• examine overall limb alignment
  
  • will often present with shortening and in varus
• preoperative or pre-reduction neurovascular exam is critical
  
  • examine and document status of radial nerve pre and post-reduction

Question 5

Radiographs

Answer 5

• AP and lateral
  
  • be sure to include joint above and below the site of injury
• transthoracic lateral
  
  • may give better appreciation of sagittal plane deformity
  • rotating the patient prevents rotation of the distal fragment avoiding further nerve or soft tissue injury
• traction views
  
  • may be necessary for fractures with significant shortening, proximal or distal extension but not routinely indicated

Question 6

Nonoperative

Answer 6

1. coaptation splint followed by functional brace

Question 7

coaptation splint followed by functional brace

indications

Answer 7

• indicated in vast majority of humeral shaft fractures
• criteria for acceptable alignment include:
• < 20° anterior angulation
• < 30° varus/valgus angulation
• < 3 cm shortening

Question 8

coaptation splint followed by functional brace

absolute contraindications

Answer 8

• severe soft tissue injury or bone loss
• vascular injury requiring repair
• brachial plexus injury

Question 9

coaptation splint followed by functional brace

relative contraindications

Answer 9

• see relative operative indications section
• radial nerve palsy is NOT a contraindication to functional bracing

Question 10

coaptation splint followed by functional brace

outcomes

Answer 10

• 90% union rate
  
  • increased risk with proximal third oblique or spiral fracture
• varus angulation is common but rarely has functional or cosmetic sequelae

Question 11

Operative

Answer 11

1. open reduction and internal fixation
2. intramedullary nailing (IMN)

Question 12

open reduction and internal fixation

absolute

and

relative indications

Answer 12

• absolute indications
  
  • open fracture
  • vascular injury requiring repair
  • brachial plexus injury
  • ipsilateral forearm fracture (floating elbow)
  • compartment syndrome
  • periprosthetic humeral shaft fractures at the tip of the stem
• relative indications
  
  • bilateral humerus fracture
  • polytrauma or associated lower extremity fracture
    
    • allows early weight bearing through humerus
  • pathologic fractures
  • burns or soft tissue injury that precludes bracing
  • fracture characteristics
    
    • distraction at fracture site
    • short oblique or transverse fracture pattern
    • intraarticular extension

Question 13

intramedullary nailing (IMN)

relative indications

Answer 13

• pathologic fractures
• segmental fractures
• severe osteoporotic bone
• overlying skin compromise limits open approach
• polytrauma

Question 14

Techniques

Coaptation Splint & Functional Bracing

Answer 14

• coaptation splint
  
  • applied until swelling resolves
  • adequately applied splint will extend up to axilla and over shoulder
  • common deformities include varus and extension
    
    • valgus mold to counter varus displacement
• functional bracing
  
  • extends from 2.5 cm distal to axilla to 2.5 cm proximal to humeral condyles
  • sling should not be used to allow for gravity-assisted fracture reduction
  • shoulder extension used for more proximal fractures
  • weekly radiographs for first 3 weeks to ensure maintenance of reduction
    
    • every 3-4 weeks after that

Question 15

Open Reduction Internal Fixation with Plating technique

Answer 15

• approaches
  
  • anterolateral approach to humerus
    
    • used for proximal third to middle third shaft fractures
    • distal extension of the deltopectoral approach
    • radial nerve identified between the brachialis and brachioradialis distally
  • posterior approach to humerus
    
    • used for distal to middle third shaft fractures although can be extensile
    • triceps may either be split or elevated with a lateral paratricipital exposure
    • radial nerve is found medial to the long and lateral heads and 2cm proximal to the deep head of the triceps
    • radial nerve exits the posterior compartment through lateral intramuscular septum 10 cm proximal to radiocapitellar joint
    • lateral brachial cutaneous/posterior antebrachial cutaneous nerve serves as an anatomic landmark leading to the radial nerve during a paratricipital approach
• techniques
  
  • plate osteosynthesis commonly with 4.5mm plate (narrow or broad)
    
    • 3.5mm plates may function adequately
  • absolute stability with lag screw or compression plating in simple patterns
  • apply plate in bridging mode in the presence of significant comminution
• postoperative
  
  • full crutch weight bearing shown to have no effect on union

Question 16

Closed Intramedullary Nailing vs plating in letrature

Answer 16

• nonunion
  
  • nonunion rates not shown to be different between IMN and plating in recent meta-analyses
  • IM nailing associated with higher total complication rates
• shoulder pain
  
  • increased rate when compared to plating (16-37%)
  • functional shoulder outcome scores (ASES scores) not shown to be different between IMN and ORIF

Question 17

Nonunion after functional brace treatment of diaphyseal humerus fractures.

Ring D

Answer 17

Compared with the epidemiology of acute diaphyseal humerus fractures, nonunions after functional bracing are more likely to follow spiral/oblique fractures that involve the mid- or proximal-third of the diaphysis. Operative treatment can gain union and improve arm function.

Question 18

Treatment of diaphyseal fractures of the humerus using a functional brace.

Rutgers M

Answer 18

Proximal-third long oblique fractures may be at greater than average risk for nonunion after functional fracture bracing.

Question 19

Humeral shaft fractures: results of operative and non-operative treatment.

Westrick E 2017

Answer 19

Conservative treatment of humeral shaft fractures has a higher rate of nonunion, while operative treatment is associated with a low incidence of iatrogenic nerve palsy but higher rates of infection.

Question 20

Humeral shaft fractures: union outcomes in a large cohort.

Answer 20

This study found high rates of delayed union and nonunion with conservative management. Patients with a significant psychiatric history may benefit from consideration of operative intervention.