Specialists

Featured on Channel NewsAsia
«  
  »

Elbow Dislocation

Basics
Description
  • Dislocation of the elbow mostly results from trauma.
  • Posterior dislocation is most common.
  • It most frequently involves people <20 years of age.
  • Rarely, elbow dislocation can occur in elderly patients after a fall.
  • Most elbow dislocations occur at the ulnohumeral joint.
  • Classification: Usually refers to the position of the ulna relative to the humerus after injury:
    • Dislocations can be classified as posterior, anterior, medial, lateral, and divergent.
    • Fracture dislocations of the elbow are associated with radial head and coronoid fractures: the terrible triad of the elbow.
    • Classification of coronoid fractures:
      • I: Avulsion of the tip
      • II: <50% of the coronoid
      • III: >50% of the coronoid
      • Large coronoid fractures are thought to be associated with anterior and posterior fracture dislocations, whereas small transverse fractures are associated with the terrible triad.
Epidemiology
Incidence
  • The highest incidence is in persons <20 years old.
  • It represents 3-6% of all children’s fractures and dislocations.
Risk Factors
  • Snowboarders have a higher risk of elbow dislocation than do skiers.
  • Sports activities
Pathophysiology
  • Posterior dislocations are most common and thought to be secondary to a fall on an outstretched hand.
  • The collateral ligaments usually are ruptured, with injury to the brachialis muscle and coronoid.
Associated Conditions
  • Fracture of the radius
  • Fracture of the ulna
  • Fracture of the humerus
  • Ulnar and median nerve injury
  • Brachial artery injury
Diagnosis
Signs and Symptoms
  • Elbow dislocation occurs mostly after trauma.
  • The patient presents with pain, swelling, elbow deformity, and inability to move the elbow.
Physical Exam
  • Assess the patient’s neurovascular status.
    • Examine the functions of the radial, median, and ulnar nerves before reduction.
      • The median nerve can be injured at the time of reduction by becoming entrapped in the joint.
      • It is crucial to check nerve function before and after reduction.
    • Evaluate the patient for brachial artery injury before reduction.
      • The brachial artery may be trapped in the joint along with the median nerve.
      • Vascular injury is an indication for immediate surgery.
  • The upper extremity should be inspected for other injuries, such as Monteggia fracture-dislocation.
  • Palpate the forearm for increased swelling or signs of compartment syndrome.
Tests
Imaging
  • Radiography:
    • AP and lateral views of the elbow are sufficient for diagnosis.
    • They should be obtained with the elbow out of the splint, to rule out subtle intra-articular fractures and dislocations.
  • CT is used for fracture dislocation of the elbow to determine the precise fracture pattern.
  • MRI scan is useful for diagnosing ligamentous injury.
Differential Diagnosis
The main differential diagnosis is associated fracture.
 
Treatment
General Measures
  • The injured arm should be immobilized and elevated, with ice packs applied to the elbow.
  • The patient should be sent to the emergency department immediately.
  • The patient’s neurovascular status must be evaluated before and after reduction.
  • The examiner rules out associated fractures.
  • Most dislocations can be treated with closed reduction, with the patient under sedation.
  • Open reduction is indicated in irreducible dislocation, i.e., one caused by soft-tissue entrapment and free fragment in the joint, or changes in neurovascular status.
  • Longitudinal traction, with gradual flexion and downward pressure on the forearm, usually reduces posterior or posterolateral dislocations.
  • After reduction, elbow ROM and stability should be checked with gentle ROM and valgus and varus stress.
    • Neurovascular function also should be examined.
  • Immobilization of the elbow in 90° of flexion with a posterior splint is recommended.
  • Duration of immobilization varies, depending on elbow stability, but generally is 1 week.
  • >3 weeks of immobilization should be avoided to prevent stiffness.
  • If any neurovascular injury is detected, a vascular or orthopaedic surgeon should be notified.
Activity
  • Gradual passive and active ROM and strengthening physical therapy should be started as soon as the immobilization device is removed.
  • No lifting is allowed for 2 weeks.
Special Therapy
Physical Therapy
Therapy involves ROM and muscle strengthening.
 
Surgery
  • Surgery is indicated for:
    • Irreducible dislocation
    • Open dislocation
    • Neurovascular entrapment
    • Certain types of associated fractures
    • Complex fracture dislocations
  • Open reduction and internal fixation are recommended for:
    • Displaced radial head fractures
    • Olecranon fractures
    • Supracondylar humerus fractures
  • Repair of complex fracture dislocations should be based on restoring stability to the elbow.
    • Should be accomplished by repair of the coronoid (if possible), restoration of the radial head or radial head replacement, or repair of the collateral ligaments
  • Total elbow arthroplasty has been used for severe fracture dislocation or missed injuries.
Follow-up
Prognosis
  • Most patients do well after closed reduction.
  • The most common residual condition after dislocation is decreased ROM (loss of 10-15° of extension).
  • Medial instability leads to late arthritis and persistent pain.
  • Surgery has not been shown to be beneficial for dislocations without fracture.
  • Complex fracture dislocations have a worse prognosis but benefit from an aggressive surgical approach.
Complications
  • Decreased ROM
  • Neurovascular injury
  • Persistent pain
  • Arthritis
  • Instability
  • Heterotopic ossification
Patient Monitoring
  • The follow-up frequency varies with the individual surgeon.
  • In general, immobilization should continue for ~1 week, depending on the stability of elbow.
  • Immobilization should be no longer than 3 weeks.
  • Clinical monitoring of compartment status and of neurovascular function is recommended for the first 12-24 hours.
Miscellaneous
Codes
ICD9-CM
832.0 Elbow dislocation
 
Patient Teaching
  • Monitor for signs of compartment syndrome.
  • Emphasize ROM exercises at home.
Prevention
  • Snowboarding is a risky sport for complex elbow fracture dislocations.
    • No methods are available to lessen this risk.
FAQ
Q: What is the long-term outcome of elbow dislocation?
A: Outcomes of dislocations without fracture are generally good. Some patients will develop arthritis symptoms and medial instability of the elbow. Outcomes of complex fracture dislocations are not as good.

Related posts:

  1. Patellar Subluxation and Dislocation
  2. A Patient’s Guide to Osteoarthritis of the Elbow
  3. Cervical Spine Trauma: Dislocation and Subluxation
  4. Elbow Arthritis
  5. A Patient’s Guide to Artificial Joint Replacement of the Elbow
May 19th, 2010 | Tags: , | Category: Dictionary

Comments are closed.