Traumatic injuries of the paediatric elbow: A pictorial review Poster No.: C-750 Congress: ECR 2009 Type: Educational Exhibit Topic: Pediatric Authors: A. M. Veitch, J. Harington, K. Franklin ; Plymouth/UK, Exeter/ UK Keywords: Trauma, fractures, Elbow, paediatric DOI: 10.1594/ecr2009/C-750 1 2 1 1 2 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 30
Learning objectives 1. 2. 3. To review normal paediatric elbow anatomy including ossification centres To demonstrate a wide range of traumatic paediatric elbow fractures on plain film To provide a systematic approach to evaluation of paediatric elbow X-rays in trauma Background Fractures of the elbow joint are common in children, accounting for 15% of all paediatric fractures. The elbow comprises both hinge and pivot joints, making patterns of injury complex. In addition, the multiple ossification centres develop at different ages and can be misinterpreted by the less experienced clinician or radiologist. Complications of elbow fractures include mal-union, non-union, elbow stiffness and neurovascular injury, and confident diagnosis is essential to enable adequate management of these injuries. Imaging findings OR Procedure details ANATOMY Radiographic assessment should include: antero-posterior view with full extension lateral view with 90 degrees of flexion Anatomical lines: Anterior humeral line (Fig.1) along anterior cortex of distal humerus on lateral view normally intersects the middle third of the capitellum displacement suggests underlying supracondylar fracture Radiocapitellar line (Fig.1&2) through longitudinal axis of proximal radius line should pass through centre of capitellum can be used on AP or lateral view displacement suggests radial head dislocation Page 2 of 30
Fig.: Fig.1Lateral view of the normal elbow demonstrating the anterior humeral line (yellow) and radiocapitellar line (blue). The anterior fat pad is visible (arrow) but not raised. The posterior fat pad is not visible in the normal elbow. Page 3 of 30
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Fig.: Fig.2AP view of the normal elbow demonstrating the radiocapitellar line (blue). Fat pads presence of normal fat pads does not exclude a fracture raised fat pads suggest significant injury even if fracture is not seen Anterior fat pad (Fig.1&3) visualised closely applied to humerus in normal elbow raised fat pad (sail sign) indicates joint effusion Posterior fat pad (Fig.3) not visible in normal elbow when visible indicates joint effusion Page 5 of 30
Fig.: Fig.3Lateral view of the elbow demonstrating a joint effusion. Both anterior and posterior fat pads are raised (arrows). Ossification centres six ossification centres appear during childhood (Fig.4&5) age of appearance can vary, often earlier in females order of appearance is important for identifying injury sequence of appearance acronym is CRITOE Table 1: Approximate age of appearance of elbow ossification centres Page 6 of 30
C apitellum 1 year R adial Head 4 years I nternal Epicondyle (Medial) 7 years T rochlea 10 years O lecranon 10 years E xternal epicondyle (Lateral) 11 years Page 7 of 30
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Fig.: Fig.4AP elbow view in a 14 year old demonstrating the ossification centres (arrows). Fig.: Fig.5Lateral elbow view in a 14 year old demonstrating the ossification centres (arrows). ELBOW TRAUMA Supracondylar distal humeral fractures: most common elbow fracture in children peak occurrence at age 2-8 years mechanism of injury: Page 9 of 30
fall on outstretched extended arm fall on olecranon in flexion associated injuries: brachial artery injury neurological (anterior interosseous nerve) imaging: (Fig.6&7) fracture line at or near olecranon fossa disruption of anterior humeral line joint effusion fractures can be subtle and follow-up films may be required Fig.: Fig.6AP and lateral elbow views showing a supracondylar fracture in a 4 year old child. The anterior humeral line is displaced (yellow). Both fat pads are raised (arrows) indicating a joint effusion. A fracture line is seen on the AP view (arrowhead). Page 10 of 30
Fig.: Fig.7AP and lateral elbow views in a 3 year old child. The supracondylar fracture line is seen on both views (arrows). Both fat pads are raised indicating a joint effusion, and the anterior humeral line is displaced. Transphyseal distal humeral fractures: separation of the entire distal humeral epiphysis usually occur before age 6 years mechanism of injury: fall on outstretched arm birth trauma non-accidental injury imaging: (Fig.8) radiocapitellar and radio-ulna relationships are intact capitellum is displaced postero-medially to distal humeral metaphysis Page 11 of 30
Fig.: Fig.8Pre- and post-operative AP views of a transphyseal fracture in a 4 year old child. There is separation of the entire distal humeral epiphysis on the preoperative image (left). The postoperative image demonstrates fixation of this fracture with metallic pins (right). Medial epicondyle fractures: usually older children age 8-15 years mechanism of injury: valgus stress direct blow violent flexion-pronation associated injuries: 50% associated with elbow dislocation ulnar nerve injury radius/olecranon/coronoid process fractures Page 12 of 30
imaging: (Fig.9&10) medial epicondyle displaced often with soft tissue swelling medial epicondyle seen within joint space in dislocation if trochlea centre visible on radiographs then medial epicondyle must be identified to avoid missing avulsion injury Fig.: Fig.9AP and lateral elbow views in an 8 year old child. The AP view demonstrates displacement of the medial epicondyle in keeping with an avulsion fracture (arrow). A joint effusion is seen on the lateral view (arrowhead). Page 13 of 30
Fig.: Fig.10AP and lateral elbow views in a 16 year old. There is anterior dislocation of the elbow, with an avulsed medial epicondyle situated within the elbow joint (arrows). Significant soft tissue swelling is seen. Medial condyle fractures: most often age 8-14 years mechanism of injury: valgus stress direct blow fall in flexion/pronation complications: avascular necrosis growth disturbance elbow instability imaging: (Fig.11&12) joint effusion intraarticular fracture line usually extends through trochlear apex or capitellotrochlear groove can be difficult to differentiate from epicondylar injury prior to ossification of trochlea Page 14 of 30
Fig.: Fig.11AP and lateral elbow views in an 8 year old child. A fracture line can be seen through the medial condyle on the AP view (arrows). The lateral view demonstrates a joint effusion. Fig.: Fig.12AP and lateral elbow views in a 1 year old child. There is posterior elbow dislocation seen on the lateral view. AP view shows a displaced medial condylar fracture fragment (arrow). Lateral epicondyle fractures: Page 15 of 30
less common injury usually children over age 11 years mechanism of injury: adductor/varus stress fall in hyperextension/supination associated injuries: lateral condylar fractures imaging: (Fig.13&14) displaced lateral epicondyle often with soft tissue swelling Fig.: Fig.13AP and lateral elbow views in a 12 year old child. A joint effusion is seen on the lateral view. The AP view demonstrates displacement of the lateral epicondyle in keeping with an avulsion fracture (arrow). Page 16 of 30
Fig.: Fig.14Anterior dislocation of the elbow in a 13 year old child. On the lateral view, multiple fracture fragments are seen within the joint space (arrow). The AP view shows avulsion of the lateral epicondyle (arrowhead). Lateral condyle fractures: most commonly age 2-8 years mechanism of injury: varus stress fall in hyperextension/supination associated injuries: elbow dislocation ulna or epicondyle fracture complications: high incidence of non-union physeal arrest avascular necrosis ulnar nerve palsy imaging: (Fig.15&16) Page 17 of 30
fracture line usually extends through trochlear notch (unstable), or lateral to trochlea (stable) Fig.: Fig.15AP and lateral elbow views in a 1 year old child demonstrating a lateral condylar fracture (arrow). The fracture line extends to the articular surface. Page 18 of 30
Fig.: Fig.16AP and lateral elbow views in a 5 year old child. There is a joint effusion, and fractures of the lateral condyle (arrow) and olecranon (arrowhead). Olecranon fractures: broad age range 2-14 years mechanism of injury: shear, flexion or extension (varus or valgus) associated injuries: lateral condyle and proximal radius fractures varus injury may sustain radial head dislocation and posterior interosseous nerve injury valgus injury may sustain radial neck and medial epicondyle fractures imaging: (Fig.17,18&19) fractures can be subtle buckle injury may occur Page 19 of 30
Fig.: Fig.17AP and lateral views in a 9 year old child demonstrating an olecranon fracture (arrow) extending to the articular surface. Page 20 of 30
Fig.: Fig.18AP and lateral views in a 4 year old child demonstrating a buckle fracture of the olecranon (arrow). Fig.: Fig.19AP and lateral views in a 13 year old demonstrating an olecranon fracture. The fracture fragment includes the ossification centre, and is displaced posteriorly (arrow). Page 21 of 30
Proximal radial fractures: most commonly 6-13 years mechanism of injury: valgus force on extended elbow shearing force associated injuries: proximal ulna and medial epicondyle fractures complications: physeal overgrowth or closure avascular necrosis radioulnar synostosis imaging: (Fig.20&21) buckle fractures may be difficult to detect common fractures types are Salter-Harris type 2, transverse metaphyseal or radial neck Page 22 of 30
Fig.: Fig.20AP and lateral views in an 11 year old child demonstrating a radial head fracture (arrows). Fig.: Fig.21AP and lateral views in a 4 year old child demonstrating a joint effusion and a radial neck fracture (arrows). Monteggia fracture-dislocation: fracture of midshaft of ulna with dislocation of radial head most often age 7-10 years most common anterior dislocation injuries mechanism of injury: direct blow fall on hyperextended or flexed elbow complications: redislocation instability Page 23 of 30
posterior interosseous nerve injury imaging: (Fig.22) displacement of the radiocapitellar line ensure forearm images obtained to identify midshaft ulna fracture congenital radial head dislocation is usually posterior with dysplastic radial head Page 24 of 30
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Fig.: Fig.22AP and lateral views in a 2 year old child demonstrating a Monteggia fracture-dislocation. There is a fracture through the midshaft of the ulna (arrows). The radiocapitellar line (blue) is displaced, indicating radial head dislocation. Dislocation of the elbow: most common joint dislocation in children peak age 13 years mechanism of injury: fall on outstretched hand in hyperextension with valgus stress associated injuries: medial epicondyle avulsion +/- ulnar nerve injury brachial artery injury median nerve injury radial or coronoid process fracture complications: recurrent dislocation imaging: (Fig.23&24) radioulnar displacement with respect to humerus check position of the medial epicondyle before and after reduction Page 26 of 30
Fig.: Fig.23AP and lateral views in an 11 year old child demonstrating anterior dislocation of the elbow. Fig.: Fig.24AP and lateral elbow views in an 11 year old child. There is anterior dislocation of the elbow, with the avulsed medial epicondyle seen within the joint space (arrow). Further small fracture fragments are seen (arrowheads). CT later demonstrated fractures of the coronoid process, capitellum and medial epicondyle. Page 27 of 30
Non-accidental injury (NAI): most frequently in under 2 year old child often no history of injury or inadequate history to explain the injury multiple fractures in different stages of healing with excessive callus (Fig.25a&b) metaphyseal fractures are typical, resulting from a twisting force spiral diaphyseal fractures can occur from rotatory injury ensure awareness of local policy for management of suspected NAI Fig.: Fig.25aAP and lateral views in a 9 month old child. There is an old healing olecranon fracture (arrow). A joint effusion and more recent metaphyseal fractures are also seen. A fracture fragment is visible adjacent to the capitellum (arrowhead). Page 28 of 30
Fig.: Fig.25bArthrogram confirming that the fracture fragment (arrowhead, Fig.25a) is within the elbow joint capsule (arrow). There is also anterior displacement of the unossified distal humeral epiphysis. EVALUATION OF ELBOW RADIOGRAPHS Table 2: An approach to evaluating the paediatric elbow Obtain AP and lateral views Check position of anterior humeral and radiocapitellar lines Assess fat pads and soft tissues Page 29 of 30
Identify ossification centres (CRITOE) Examine bones for fracture lines Look for associated injuries Consider NAI where unusual history or injury pattern Conclusion This pictorial review of elbow fractures in children aims to provide a practical aide-memoir to both trainee and general radiologists involved in reporting paediatric trauma plain films. Personal Information Thank you to the Medical Photography Department at Derriford Hospital, Plymouth (UK) for production of the images. References 1. 2. 3. 4. S.John, K.Wherry, L.Swischuk, W.Phillips. Improving Detection Of Pediatric Elbow Fractures By Understanding Their Mechanics. RadioGraphics 1996; 16:1443-1460. J.Tamai, J.Lou, S.Nagda, T.Ganley, J.Flynn. Pediatric Elbow Fractures: Pearls And Pitfalls. UPOJ 2002; 15:43-51. M.Brinker. Review of Orthopaedic Trauma. 2001. Philadelphia: Saunders. N.Raby, L.Berman, G.deLacey. Accident and Emergency Radiology: A nd Survival Guide. 2005 2 5. ed. London: Elsevier. th W.Dahnert. Radiology Review Manual. 2003 5 ed. Philadelphia: Lippincott Williams and Wilkins. Page 30 of 30