Posterior Elbow Dislocation


Article Author:
James Waymack


Article Editor:
Jason An


Editors In Chief:
Jon Parham
Jon Sivoravong


Managing Editors:
Avais Raja
Orawan Chaigasame
Carrie Smith
Abdul Waheed
Khalid Alsayouri
Kyle Blair
Trevor Nezwek
Radia Jamil
Erin Hughes
Patrick Le
Anoosh Zafar Gondal
Saad Nazir
William Gossman
Hassam Zulfiqar
Navid Mahabadi
Hussain Sajjad
Steve Bhimji
Muhammad Hashmi
John Shell
Matthew Varacallo
Heba Mahdy
Ahmad Malik
Abbey Smiley
Sarosh Vaqar
Mark Pellegrini
James Hughes
Beata Beatty
Daniyal Ameen
Altif Muneeb
Beenish Sohail
Nazia Sadiq
Hajira Basit
Phillip Hynes
Komal Shaheen
Sandeep Sekhon


Updated:
1/6/2019 9:38:23 AM

Introduction

The elbow joint is considered relatively stable; however, elbow dislocations are a fairly common occurrence. This injury frequently occurs during sporting activities when a person falls on an extended elbow. In most instances, the semilunar notch of the ulna is dislocated posteriorly from the distal humerus. If there is no fracture associated with the dislocation, it is described as simple, and the injury is often closed with no bony protrusion through the skin.[1][2]

The stability of the elbow joint due to its bony structure means that significant force is required to disrupt the joint. Therefore, an associated fracture may be found along with the elbow dislocation thus classifying the dislocation as complex. Neurovascular complications are rare from a simple, closed, posterior dislocation. The less encountered anterior elbow dislocation requires much more force and concern for neurovascular compromise should be greater. A dislocated elbow necessitates immediate closed reduction to prevent complications.  Recurrent elbow dislocations suggest chronic joint instability and may require operative fixation.

Etiology

A posterior elbow dislocation often occurs when a person falls on an outstretched hand, posteriorly directed force at the elbow joint causes dislocation at the ulnohumeral and radiocapitellar articulations. Valgus force may induce the commonly seen posterolateral elbow dislocation.   [3][4][5]

Anterior elbow dislocations occur when the elbow is flexed, and there is a direct blow on the posterior aspect of the elbow.

Epidemiology

Elbow dislocation is the most common joint dislocation in pediatric patients and the second most common in adult patients. The incidence is reported at 6 to 13 per 100,000 persons per year. The injury more often occurs in adolescent male athletes. Specifically, varsity football and wrestling participants are particularly susceptible to this injury.  Posterior elbow dislocations comprise 90% of all elbow dislocations.[6][7][8]

Pathophysiology

Considering elbow anatomy and the likely mechanism of injury causing an elbow dislocation can help one understand the pathophysiology associated with this particular injury. During a posterior elbow dislocation, the shearing forces causing the injury may cause associated radial head, radial neck or coronoid process fractures. The medial collateral and lateral collateral ligaments provide support to the elbow joint in addition to its bony anatomy. The LCL is often disrupted when an elbow dislocation occurs; the MCL is the last soft tissue structure injured as the ulna is displaced. Often, the flexor-pronator mass may be ruptured, and occasionally the brachialis may be injured.

The anterior compartment of the elbow encompasses the brachial artery and ulnar and median nerves. These structures are particularly vulnerable to injury because the anterior compartment is often disrupted during posterior dislocation. The ulnar nerve may become entrapped as it passes posteriorly around the medial epicondyle. The brachial artery and median nerve travel closely to one another and injuries are often seen in both these structures simultaneously.

Anterior dislocations are often associated with olecranon fractures.  These dislocations may also disrupt the posterior elbow compartment which contains the radial nerve and insertion of the triceps muscle.

History and Physical

All patients experiencing traumatic injury should first be assessed head to toe for any life or limb threatening injuries first. Obvious bony deformities may distract both the patient and the practitioner from more serious traumatic injuries. After the patient has been cleared of other significant injuries, attention can be turned to the affected extremity.

The initial history should consist of the mechanism of injury and the duration of the injury until initial presentation. The patient should be asked if this is a first-time occurrence or if there have been previous elbow injuries in the past. A physician should review associated symptoms suggesting a neurovascular compromise and inquire about numbness, tingling or coolness of the distal extremity.

The physical examination should begin with an inspection of the elbow joint looking for swelling, deformity or bruising. Posterior elbow dislocations often present with an upper extremity that is flexed and appears shortened. Anterior elbow dislocations are held in extension, and the upper extremity appears elongated. Specific attention should be paid to looking for open wounds which would suggest a complex dislocation. The functionality of the elbow joint should be assessed by observing a range of motion. It is also important to evaluate the remainder of the affected extremity and nearby joints for associated injury. Particular attention should be paid to the distal radioulnar joint for tenderness which can indicate disruption of the intraosseous ligament, eponymously referred to as an Essex-Lopresti lesion.

The most common neurovascular structures injured during an elbow dislocation include the brachial artery and the ulnar and median nerves. Perfusion can be assessed by palpating the radial and ulnar pulses and looking for a brisk capillary refill. Median nerve sensation can be assessed by a light touch of the palmar aspect of the thumb and second finger. Median motor function is tested by observing the strength of thumb opposition. A light touch on the palmar aspect of the fourth and fifth fingers can assess ulnar sensation. The ulnar motor function is tested by observing the strength of finger abduction and adduction.  Historical or physical findings concerning for neurovascular compromise must also raise the suspicion for compartment syndrome.

Evaluation

Initial evaluation of a suspected elbow dislocation should begin with anterior-posterior and lateral plain radiographs with attention to joint congruency and potential fractures. Oblique views may be best to evaluate for periarticular fractures. Computerized tomography may be considered if there is a concern for a complex injury or to identify periarticular fractures not easily seen on plain radiographs. Repeat radiographs to ensure adequacy and maintenance of reduction should be obtained after manipulation. Attention should be paid to normal radiocapitellar alignment in values to demonstrate adequate reduction.

Treatment / Management

Initial treatment of simple, closed posterior elbow dislocations is closed reduction. Some complex elbow dislocations may initially be treated with closed reductions; however, associated fracture implies significant soft tissue damage and likely persistent instability which may require open reduction and internal fixation to improve outcomes. Open dislocations will require extensive washout during an open reduction. Any dislocation with signs of neurovascular compromise requires immediate closed reduction.[9][2]

There are two common approaches to the reduction of a posterior elbow dislocation. It is recommended the first technique is attempted in the prone position. With the patient laying down the affected arm is abducted with an elbow on the edge of the cart. The wrist is then grasped and the forearm placed in slight supination while gentle traction is applied. The coronoid process must be distracted and disengaged from the olecranon fossa. Once this has been accomplished downward pressure with the other hand on the olecranon should reduce the dislocation with the operator feeling a confirmatory clunk. A two-person technique is also described where one operator applies downward traction at the wrist, and other applies the downward force onto the olecranon with both their thumbs.

The alternative method is performed with the patient seated or lying supine on the cart. An assistant stabilizes the affected humerus while the operator flexes the elbow, supinates the wrist slightly and applies distal and downward traction at the wrist with one hand. The other hand is placed just distal to the elbow on the volar aspect of the forearm applying slow, gentle inline traction until the confirmatory clunk is appreciated.

Following reduction of the dislocation, a neurovascular examination should be performed to identify improvement in any previous neurovascular symptom or a new symptom that may have manifested following the reduction.  The elbow should be held in 90 degrees of flexion for 5 to 10 days followed by an active range of motion. Earlier range of motion has demonstrated better physical outcomes. Dislocations that appear more unstable may require up to 3 weeks of splinting and a specific range of motion plan. Post-reduction films should be obtained.

Pearls and Other Issues

An important consideration when evaluating the elbow dislocation is the “terrible triad” when a posterior dislocation occurs with associated radial head and coronoid process fractures. This injury pattern is due to a particularly forceful mechanism that disrupts the LCL and other soft tissues of the elbow joint. Historically, this pattern had very poor outcomes, but newer surgical techniques are proving to lead to more favorable results.

Enhancing Healthcare Team Outcomes

Elbow dislocations are fairly common in clinical practice, however, they can be associated with neurovascular compromise. Hence, the primary care provider, nurse practitioner and emergency department physician should always refer these patients to the orthopedic surgeon. The prognosis for most elbow dislocations is good but in some cases, recurrence is a problem.


Interested in Participating?

We are looking for contributors to author, edit, and peer review our vast library of review articles and multiple choice questions. In as little as 2-3 hours you can make a significant contribution to your specialty. In return for a small amount of your time, you will receive free access to all content and you will be published as an author or editor in eBooks, apps, online CME/CE activities, and an online Learning Management System for students, teachers, and program directors that allows access to review materials in over 500 specialties.

Improve Content - Become an Author or Editor

This is an academic project designed to provide inexpensive peer-reviewed Apps, eBooks, and very soon an online CME/CE system to help students identify weaknesses and improve knowledge. We would like you to consider being an author or editor. Please click here to learn more. Thank you for you for your interest, the StatPearls Publishing Editorial Team.

Posterior Elbow Dislocation - Questions

Take a quiz of the questions on this article.

Take Quiz
A 17-year-old male presents from a wrestling meet with pain and deformity of his right elbow. He also has pain at the volar aspect of his forearm between the radius and the ulna. What associated injury should be of greatest concern?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
A 17-year-old football player arrives at the emergency department from homecoming game with severe pain and swelling at his right elbow. An orthopedic physician attending the game made a presumptive diagnosis of posterior elbow dislocation. What is the likely mechanism of injury?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
Which of the following is not part of the "terrible triad" injury described with elbow dislocations?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
A 17-year-old female fell onto an outstretched hand just before arrival. She has pain and swelling at the elbow joint and describes tingling and decreased sensation of her 4th and 5th fingers. What neuromuscular structure was likely injured?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
A 17-year-old male presents with a posterior elbow dislocation. What position is recommended for the initial attempt at reduction of the elbow?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up

Posterior Elbow Dislocation - References

References

Aroojis A,Narula V,Sanghvi D, Pure Medial Elbow Dislocation without Concomitant Fracture in a 10-Year-Old Child. Indian journal of orthopaedics. 2018 Nov-Dec;     [PubMed]
Cho CH,Kim BS,Rhyou IH,Park SG,Choi S,Yoon JP,Choi CH,Dan J, Posteromedial Elbow Dislocations without Relevant Osseous Lesions: Clinical Characteristics, Soft-Tissue Injury Patterns, Treatments, and Outcomes. The Journal of bone and joint surgery. American volume. 2018 Dec 5;     [PubMed]
Mortimer AE,Nicholls A,Rawal A,Noor S,Oy H,Gollogly JG, The burden of chronic elbow dislocations in Cambodia and early results of a cost-effective surgical approach. Tropical doctor. 2018 Nov 12;     [PubMed]
Schubert I,Strohm PC,Zwingmann J, [Simple elbow dislocations in children : Systematic review and meta-analysis]. Der Unfallchirurg. 2018 Nov 6;     [PubMed]
Rahman M,Cil A,Stylianou AP, Medial Collateral Ligament Deficiency of the Elbow Joint: A Computational Approach. Bioengineering (Basel, Switzerland). 2018 Oct 10;     [PubMed]
Tomori Y,Nanno M,Takai S, Posteromedial elbow dislocation with lateral humeral condylar fracture in children: Three case reports and a literature review. Medicine. 2018 Sep;     [PubMed]
Gottlieb M,Schiebout J, Elbow Dislocations in the Emergency Department: A Review of Reduction Techniques. The Journal of emergency medicine. 2018 Jun;     [PubMed]
Lim SM,Chua GG,Asrul F,Yazid M, Posterior Elbow Dislocation with Brachial Artery Thrombosis Treated Non-surgically: A Case Report. Malaysian orthopaedic journal. 2017 Nov;     [PubMed]
Conti Mica M,Caekebeke P,van Riet R, Lateral collateral ligament injuries of the elbow - chronic posterolateral rotatory instability (PLRI). EFORT open reviews. 2016 Dec;     [PubMed]

Disclaimer

The intent of StatPearls is to provide practice questions and explanations to assist you in identifying and resolving knowledge deficits. These questions and explanations are not intended to be a source of the knowledge base of all of medicine, nor is it intended to be a board or certification review of Family Medicine. The authors or editors do not warrant the information is complete or accurate. The reader is encouraged to verify each answer and explanation in several references. All drug indications and dosages should be verified before administration.

StatPearls offers the most comprehensive database of free multiple-choice questions with explanations and short review chapters ever developed. This system helps physicians, medical students, dentists, nurses, pharmacists, and allied health professionals identify education deficits and learn new concepts. StatPearls is not a board or certification review system for Family Medicine, it is a learning system that you can use to help improve your knowledge base of medicine for life-long learning. StatPearls will help you identify your weaknesses so that when you are ready to study for a board or certification exam in Family Medicine, you will already be prepared.

Our content is updated continuously through a multi-step peer review process that will help you be prepared and review for a thorough knowledge of Family Medicine. When it is time for the Family Medicine board and certification exam, you will already be ready. Besides online study quizzes, we also publish our peer-reviewed content in eBooks and mobile Apps. We also offer inexpensive CME/CE, so our content can be used to attain education credits while you study Family Medicine.