snap to grid Radiological diagnosis of injuries following Fall on outstretched hand (FOOSH) Core Radiology Clerkship Beth Israel Deaconess Medical Center Ziad Obermeyer, MS4 Gillian Lieberman, MD 18 September 2006
HAND INJURIES ARE VERY COMMON IN ED, AND FALL IS ONE OF THE MOST IMPORTANT MECHANISMS Body surface area Injuries presenting to ED Hand injuries: mechanisms (meta-analysis)* Location AVG Dk (2) UK (3) N Ir (4) Nl/Dk (1) Year 1991 1991 1995 1997-8 N 535800 50272 2655 4873 478000 Cut/bite 31 46 28.7 17.3 31 Fall 22 23 29 15 - Punch/ assault 17 27 22 2.6 - Sport 16-19 15 15 Palm: 1% of TBSA Hands: ~4-8% of TBSA Hands: 29% of all injuries treated in ED (Dutch & Danish surveillance data [1]) Falls account for 22 percent of all visits to ED for hand injuries Images from http://www.anatomyatlases.org/atlasofanatomy/index.shtml: Bock s Handbuch der Anatomie des Menschen (1841), tr. Bergman RA, Afifi AK. * Averages not weighted to correct for sampling bias of individual studies. (1) Larsen CF, Mulder S, Johansen AM, Stam C. The epidemiology of hand injuries in the Netherlands and Denmark. Eur J Epi 2004; 19.323-327. (2) Angermann P, Lohmann M. Injuries to the hand and wrist: A study of 50,272 injuries. J Hand Surg (Br) 1993; 18B.5:642-4. (3) Packer GJ, Shaheen MA. Patterns of hand fractures and dislocations in a district general hospital. J Hand Surg (Br)1993; 18B.5:511-514. (4) Hill C, Riaz M, Mozzam A, Brennen MD. A regional audit of hand and wrist injuries. J Hand Surg (Br); 23B.2: 196-200.
BEFORE WE CONTINUE, A QUICK GLIMPSE OF WHAT WE RE NOT COVERING: DISTAL INJURIES A SELECTION OF BOSTON SEASONAL VARIANTS Summer: Foul ball at Fenway Winter: Snowblowing the driveway Oblique fx of 4 th DP Volar displacement Comminuted fx of R 2 nd, 3 rd, 4 th MPs and DPs 3 rd MP displaced radially Associated soft tissue defects Distal hand fractures most common site of injury in epidemiological studies Straightforward diagnosis and treatment where s the challenge? Let s move on to wrist fractures BIDMC, PACS
OUTLINE: WRIST FRACTURES RESULTING FROM FALLS 1. Differential diagnosis of wrist pain following FOOSH Colles Scaphoid fx SL lig tear Trangular fibrocartilage complex (TFCC) tear 2. Case presentations: radiological involvement in each diagnosis Highlights of normal anatomy What s at stake: importance of early diagnosis and treatment 1st line imaging and tricks Backup imaging
OUTLINE: WRIST FRACTURES RESULTING FROM FALLS 1. Differential diagnosis of wrist pain following FOOSH Colles Scaphoid fx SL lig tear Trangular fibrocartilage complex (TFCC) tear 2. Case presentations: radiological involvement & imaging for each diagnosis Highlights of normal anatomy What s at stake: importance of early diagnosis and treatment 1st line imaging and tricks Backup imaging
ACCURATE AND TIMELY DIAGNOSIS AND TREATMENT CAN AVOID COMPLICATIONS OF HAND & WRIST FRACTURES Potential complications 1st line imaging modality 2nd line imaging modality 1. Distal radius fracture (Colles) OA Strength deficit, instability Plain film CT MRI Bone 2. Scaphoid fracture OA Plain film CT Avascular necrosis MRI Malunion 3. Scapholunate ligamentous tear OA Wrist instability Plain film Arthroscopy Arthrography Soft tissue 4. Trangular fibrocartilage complex (TFCC) tear Scapholunate advanced collapse OA Arthroscopy Arthrography (none) Goldfarb CA, Yin Y, Giluta LA, Boyer, MI. Wrist fractures: What the clinician wants to know. Radiology 2001; 219:11-28
NORMAL HAND AND WRIST ANATOMY IS CONFUSING, AND CHARACTERISED BY UNHELPFUL MNEMONICS Normal PA film Normal lateral film Notes Bones How can a mnemonic with eight letters have three T s? TriQuetrum Ulna Trapezium near the thumb Only Trapezoid is left Thumb is missing a Ligaments Any permutation you can imagine Strength ligaments volar Arteries Ulnar Radial Nerves Median Ulnar Radial BIDMC, PACS
OUTLINE 1. Differential diagnosis of wrist pain following FOOSH Colles Scaphoid fx SL lig tear Trangular fibrocartilage complex (TFCC) tear 2. Case presentations: radiological involvement & imaging for each diagnosis Highlights of normal anatomy What s at stake: importance of early diagnosis and treatment 1st line imaging and tricks Backup imaging
PATIENT 1: FALL DOWN STAIRS COLLES FRACTURE Patient 1 Patient 1 s PA hand film Normal comparison PA film 65F Pain in my hand Had 1/2 glass of wine and fell down stairs PMH: HTN Meds: ASA, HCTZ, black cohosh SHx: menopause FHx: n/c PE: tender prox to wrist Distal radius fracture Ulnar styloid avulsed BIDMC, PACS
RELEVANT ANATOMY: DISTAL RADIUS AND RADIO-CARPAL JOINT HAS SEVERAL INTERESTING BONY AND SOFT TISSUE FEATURES Normal hand: PA film Normal hand: lateral film Anatomical features Pathological features following fracture 1. Metaphyseal widening 2cm from joint: less cortical, more cancellous bone 1. Less density is fracture set up Osteoporosis screening 2. Radius longer than ulna Radius bears 80% of strain 2. Shortened radius Ulnar loading, OA Muscle spasm 3. Triangles Volar tilt (11 ) Ulnar inclination: loads radius 3. Triangles Dorsal angulation in Colles fx loads ulna 4. TFCC cartilage Joins radius to ulnar styloid 4. TFCC cartilage Frequent avulsion of ulnar styloid Goldfarb CA, Yin Y, Giluta LA, Boyer, MI. Wrist fractures: What the clinician wants to know. Radiology 2001; 219:11-28
FOR COMPLEX INTRA-ARTICULAR FRACTURES OF DISTAL RADIUS, 2D CT RECONSTRUCTION CAN BE VALUABLE Companion case: CT slices Left to right, top to down Companion case: 2D CT reconstruction Coronal Sagittal Coronal reconstruction shows clear scaphoid fracture and sagittal shows small associated lunate fracture. BIDMC, PACS
AND 3D CT RECONSTRUCTION CAN SIGNIFICANTLY INCREASE DIAGNOSIC ACCURACY, AND CHANGE SURGICAL DECISION-MAKING Companion case: PA & lat films, 3DCT reconstruct n leading to complex internal fixation Multiple intra-articular fractures Increases reliability and diagnostic accuracy Significantly changes surgical decision-making vs plain films (1) (1) Harness NG, Ring D, Zurakowski D, Harris GJ, Jupiter JB. The influence of 3D CT reconstructions on the characterization and treatment of distal radius fractures. JBJS (Am) 2006; 88.6:1315-23. Images reproduced from (1).
PATIENT 2: FALL WHILE HORSEPLAYING Patient 2 27M Pain in my hand Had one beer, was discussing baseball with friend from NYC PMH: none Meds: none SHx: painter FHx: n/c PE: tender snuffbox Images courtesy of Dr Jim Wu, BIDMC Radiology
PATIENT 2: CORRECT VIEWS EXPOSE OCCULT SCAPHOID FRACTURE PA hand film (as seen in previous slide) PA hand film with ulnar deviation VS High degree of clinical suspicion required to diagnose occult fractures Correct views also required! (request scaphoid views, not wrist) If still unsure, can cast and re-image in 2 weeks, to avoid additional imaging Images courtesy of Dr Jim Wu, BIDMC Radiology
SCAPHOID ANATOMY: ORIENTED OBLIQUELY, WITH VASCULAR SUPPLY EXEMPLIFYING LESS-THAN-INTELLIGENT DESIGN Scaphoid orientation & vasculature Notes 1. Bony orientation of scaphoid Not parallel to plane of palm Radial side volar, ulnar side dorsal Need oblique views! 2. Vasculature 80% of supply from dorsal branches of radial artery, entering at scaphoid waist 20% from palmar branches entering at distal pole Negligible supply from SL ligament, SRL ligament AVN risk increases with more proximal fracture location, approaching 100% with proximal pole fractures Image reproduced from www.eorthopod.com Goldfarb CA, Yin Y, Giluta LA, Boyer, MI. Wrist fractures: What the clinician wants to know. Radiology 2001; 219:11-28
PATIENT 3: WRIST PAIN SEVERAL DAYS FOLLOWING FALL Patient 3 Patient 3 s PA hand film Normal comparison 42F Pain in my hand At a cocktail party, was pushed by agent from competing real estate agency PMH: none Meds: none SHx: smokes half pack x20y FHx: n/c PE: tender snuffbox Images courtesy of Dr Jim Wu, BIDMC Radiology
DIAGNOSIS OF AVASCULAR NECROSIS IS CHALLENGING Does Patient 3 have AVN? (PA film) Patient 3 s MRI Fat subtraction shows blood filling distal to fracture, but filling defect proximal Diagnostic of avascular necrosis Images courtesy of Dr Jim Wu, BIDMC Radiology
PATIENT 4: SPORTS INJURY SCAPHOLUNATE LIGAMENT TEAR Patient 4 67M Pain in my hand Bicyclist struck by car and thrown, used hand to break fall PMH: none Meds: MVI SHx: n/c FHx: mother, father with OA PE: +Watson test (painful snap w/ volar scaphoid pressure, uln to rad dev)
MR ARTHROGRAPHY CAN DIAGNOSE SUBTLE LIGAMENTOUS TEARS, THOUGH FALSE POSITIVES ARE COMMON Evaluation based on visualization of contrast in compartments of hand Indirect MR arthrography is not superior to traditional arthrography (1) However, difficult to differentiate clinically irrelevant pinhole communications vs real tear (2) Scapholunate ligament tear MR arthrograph with gadolinium injection TFCC tear MR arthrograph with gadolinium injection Radiocarpal gadolinium injection Gadolinium diffuses out of radiocarpal compartment Indicates ligamentous disruption (1) Schadel-Hopfner M, Iwinska-Zelder J, Braus T, et al. MRI versus arthroscopy in the diagnosis of scapholunate ligament injury. J Hand Surg (Br) 2001; 26B.1:17-21. (2) Sahin G, Demirtas M. An overview of MR arthrography with emphasis on the current technique and applicational hints and tips. Eur J Radiol 2006; 58:416-430.
SUMMARY 1. Radiology plays a critical role in establishing diagnosis of wrist pain following FOOSH, and directing treatment plan Clinical differentiation among various etiologies nearly impossible given similarities of symptoms 2. Fractures of the distal radius are common, particularly in the elderly, and can have debilitating consequences Osteoporosis screening Associated injuries 3D CT reconstruction is promising way to characterize complex intraarticular fractures 3. Scaphoid fractures are easy to miss one of the most common causes of litigation vs radiologists and can lead to avascular necrosis of the proximal pole Correct views are essential MR can aid in diagnosis of AVN 4. Ligamentous tears can be difficult to diagnose with non-invasive means, but early diagnosis and treatment can help to avoid late complications
THANK YOU Dr Gillian Liebermann Pamela Lepkowski Dr Jim Wu Dr Justin Kung Larry Barbaras Radiology, BIDMC Radiology, BIDMC Radiology, BIDMC Radiology, BIDMC Radiology, BIDMC Dr Charles Day Dr Andetta Hunsaker Dr Rajan Agarwal Dr M Vincent Makhlouf Orthopedics, BIDMC Radiology, BWH Radiology, UPMC Plastic Surgery