Imaging of thoracic injuries in professional rugby players: Role of magnetic resonance imaging (MRI) and computed tomography (CT)

Transcription

1 Imaging of thoracic injuries in professional rugby players: Role of magnetic resonance imaging (MRI) and computed tomography (CT) Poster No.: C-1318 Congress: ECR 2012 Type: Educational Exhibit Authors: D. Hayashi, F. W. Roemer, R. Kohler, A. Guermazi, C Gebers, R. de Villiers ; Boston, MA/US, Augsburg/DE, Bruce/ 4 5 AU, Boston, MA, MA/US, Somerset West/ZA Keywords: Trauma, Athletic injuries, Imaging sequences, MR, CT, Thorax, Thoracic wall DOI: /ecr2012/C-1318 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. Page 1 of 23

2 Learning objectives To illustrate types of thoracic injuries sustained by professional rugby players with a focus on MRI and CT findings. Background Background: Rugby is a popular sport world-wide, performed on a recreational and professional level. Traumatic thoracic injuries in rugby players are much less common compared to lower limb injuries (Table 1), but the players are relatively more prone to such injuries due to the minimal protective wear compared to American Football players who wear a large protective gear and a helmet. Imaging plays an important role in the initial diagnosis and follow-up of such injuries. Imaging findings OR Procedure details 1. Overview of presentation: Incidence of thoracic injuries in professional rugby players Review of the anatomy of the thoracic cage and major muscles attached to it Pictorial review of different types of thoracic injuries including the sternum, ribs, cartilage, clavicles, costovertebral joints, and muscles, primarily using CT and MRI Conclusion 2. Incidence of thoracic injuries 2-1. Data from the International Rugby Board Rugby World Cup 2007 injury surveillance study [1]: 48 matches in 7 weeks 1920 player-hours (1024 forwards, 896 backs) for matches Upper back/sternum/ribs: 8.3/1000 player-hours for match injuries = rare type of injury (cf. Lower limb: 45.8/1000 player-hours) Page 2 of 23

3 More common in forwards (10.7/1000 player-hours) thank backs (5.6/1000 player-hours), but when sustained injury was more severe in backs (12.4 days lost from matches) than in forwards (5.8 days) Types of trunk injuries (including chest, abdomen and back) occurred: bone 14.6%; non-osseous joint structures/ligament 33.1%; muscle/tendon 43.1%; others 9.2% Match injury profile of professional rugby union players by individual playing position Data from a 4-season prospective cohort study [2]: 14 English Premiership clubs and 899 players Risk of absence due to chest injuries was higher in: (A) full-backs than other backs due to: Costochondral/sternal injury: 51 days absence/1000 hours, risk ratio to other backs (RR) 2.27 Rib fracture/contusion: 36 days absence/1000 hours, RR 1.93 (B) loose-head prop's than other forwards due to: Rib fracture/contusion: 50 days absence/1000 hours, RR to other forwards (RR) 3.51 Pneumothorax: 25 days absence/1000 hours, RR Anatomy of thoracic cage Page 3 of 23

4 Fig. 2: Anatomy of the thoracic cage 3-1. Sternum: Articulates to clavicles and cartilaginous part of ribs Attachment sites for the sternocleidomastoid and pectoralis major muscles Comprises the body, manubrium and xiphoid process Manubriosternal joint: 70% cartilage with fibrocartilage disc and 30% synovial Xiphisternal joint: cartilage joint, converts to synostosis at 15 years Sternal injuries: Sternal contusion Page 4 of 23

5 Fig. 3: 20-year old man with sternal contusion. Axial and coronal STIR images show abnormal hyperintensity in the right superior corner of the manubrium indicating a bone contusion (arrows). Acute manubriosternal injury with retrosternal haematoma Fig. 4: 21-year old man with acute manubriosternal injury. Axial and coronal STIR images show abnormal hyperintensity around the manubriosternal joint representing soft tissue hematoma (orange arrow). There is partial delamination of posterior sternal synchondrosis indicating a fracture (red arrow). Note peri-synchondrotic bony contusion (white arrows). Page 5 of 23

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7 Fig. 5: The same patient as the previous figure (21-year old man) with acute retrosternal haematoma. Sagittal STIR and T1-weighted images show a fluid collection directly adjacent to the posterior cortex of the manubrium, immediately below the manubriosternal joint (arrows). Hyperintensity on both STIR and T1-weighted images is seen, consistent with haematoma. Manubriosternal disruption Fig. 6: 28-year old man with acute manubriosternal disruption. Coronal and sagittal STIR images show fluid-equivalent signal within the synchondrosis indicating a tear (red arrows). Sagittal STIR image shows delamiantion of the posterior ossified capsule (white arrow) Sternoclavicular joint: Page 7 of 23

8 Fig. 7: Sternoclavicular joint Double plane joint Subdivided by articular disc Page 8 of 23

9 Formed by 3 units: sternal end of clavicle; cartilage of the 1st rib; clavicular notch of the manubrium Ligaments: capsular; sternoclavicular; costoclavicular; interclavicular Sternoclavicular dislocation Fig. 8: 22-year old man with capsular joint injury suggesting status after right sternoclavicular joint dislocation. Correct articulation at the time of imaging. Axial and coronal STIR image shows the disrupted right sternoclavicular joint capsule with hyperintense fluid-equivalent signal extending from the joint into the surrounding soft tissues (red arrow). No bony injury is seen. Page 9 of 23

10 Fig. 9: 49-year old man with bilateral persistent posterior sternoclavicular joint dislocation at the time of imaging. Axial high-resolution CT image shows posterior dislocation especially on the left and discongruity of the joint on both sides with a widened joint space (arrows). Page 10 of 23

11 Fig. 10: 21-year old man with a status after left sternoclavicular joint dislocation. Coronal STIR image shows joint capsule disruption with periarticular high-intensity hematoma (green arrow) and fluid within the joint space (red arrow) Ribs: Page 11 of 23

12 Fig. 11 Page 12 of 23

13 12 ribs per side normally (variations: 11 per side; extra cervical or lumbar rib) 7 true ribs (1st-7th, attached to the sternum) and 5 false ribs (8-10th, attached to the rib immediately above; 11th and 12th, free at the anterior ends (not shown in the figure) Joints associated with ribs (see figure below) Fig. 12: Joints associated with ribs Rib injuries Page 13 of 23

14 Fig. 13: Rib fractures may be missed by conventional radiography or ultrasound. CT plays an important role, especially in regard to chondral fractures (arrow). Always do CT with MPR/VRT. Most common in 5th-9th ribs CT and MRI plays an important role, especially in regard to chondral fractures. Both should be used in acute stage. For MRI, patient should be in a prone position and a marker should be placed. Axial and coronal oblique STIR should be obtained. T1-weighted sequence is not useful. Artifacts are expected due to pulsation and breathing. Consider nuclear medicine imaging for delayed stage. Page 14 of 23

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16 Fig. 14: For MRI, patient should be in a prone position and a marker should be placed. Axial and coronal oblique STIR should be obtained. T1-weighted sequence is not useful. Artifacts are expected due to pulsation and breathing. Fig. 15: 28-year old man with a subtle left 4th and 5th chondral fractures. Fracture line (yellow arrow) can be seen on CT, but it is not obvious and can easily be missed. Coronal STIR image, on the other hand, clearly depicts the fractures (red arrows) with associated fluid accumulation around the fracture sites. Fig. 16: 26-year old man with a left 8th chondral fracture with haematoma. Fracture line (yellow arrows) can be seen on both axial T1-weighted and STIR images. Axial and oblique coronal STIR images clearly depict the associated fluid accumulation around the fracture site, and T1-weighted image shows hyperintensity, consistent with haematoma (white arrow). Page 16 of 23

17 Fig. 17: 27-year old man with fracture of the left 7th costal cartilage (arrow). Oblique coronal STIR image demonstrates the site of fracture and surrounding hematoma. Inferior dislocation of lateral portion of chondral rib (arrowhead). Page 17 of 23

18 3-4 Muscles: Pectoralis major Fig. 18: Pectoralis major Fig. 21: 40-year old man with right-sided pectoralis major tear. Axial and coronal STIR images show intramuscular grade 2 strain with fibre disruption and hematoma (arrows). Page 18 of 23

19 Rectus abdominis Fig. 19: Rectus abodominis Page 19 of 23

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21 Fig. 22: 22-year old athlete with left-sided rectus abdominis tear. Axial and coronal STIR image show grade 2 lesion of the middle portion of left sided M. rectus abdominis (orange arrow) and grade 1 strain of the superior part (red arrow). Note marked intraand extrafascial hematoma (arrowheads). Transversus abdominis/internal oblique Fig. 20: Transversus abdominis/oblique Fig. 23: 25 year-old man with right-sided internal oblique muscle tear (grade 2). Axial and coronal STIR images show fluid-equivalent signal within right internal oblique muscle (red arrow) and epifascial edema (green arrow). Page 21 of 23

22 3-5 Other injuries: Thoracic spine: secondary to a blow from the back or a fall on the back Internal organs can rarely be injured secondary to sternal/rib injuries (e.g. cardiac contusion/tamponade, pneumothorax/haemothorax) 4. Conclusion: Subtle injuries may be missed on conventional radiography Multimodality imaging including MRI and CT plays an important role in the diagnostic process Cross-sectional imaging helps in the decision-making process concerning return to training and competition This exhibit will help the viewers in understanding the importance of MRI and CT in the initial assessment and follow-up of acute thoracic injuries in professional rugby players. Conclusion Subtle injuries may be missed on conventional radiography. Multimodality imaging including MRI and CT plays an important role in the diagnostic process. This exhibit will help the viewers in understanding the importance of MRI and CT in the initial assessment and follow-up of acute thoracic injuries in professional rugby players. Personal Information Conflict of Interest Statement: Dr. Guermazi is the President of Boston Imaging Core Lab (BICL), LLC, and is a Consultant to Merck Serono, Genzyme, AstraZeneca, Novartis and Stryker. Dr. Roemer is the Vice President of BICL, LLC, and is a Consultant to Merck Serono and National Institute of Health. Other authors declared nothing to disclose. Page 22 of 23

23 References Fuller et al. International rugby board rugby world cup 2007 injury surveillance study. Br J Sports Med 2008; 42: Brooks et al. Injury-prevention priorities according to playing position in professional rugby union players. Br J Sports Med 2011; 45: Standring S. Gray's anatomy, 40th edition. Curchill Livingstone (2009) - for all anatomy related information presented in this poster Page 23 of 23