X-Ray Rounds Wrist Mark Scott Nov. 8, 2007

Systematic Approach Fracture Identification, Look for: Mal-alignment Discontinuity Radio-lucency / radio-opacity Fat pads MALALIGNMENT - IS THERE A DISTORSION OF NORMAL ANATOMY? DISCONT - IS THERE A GAP IN THE CORTEX? RADIO-LUCENCY - IS PART OF THE FILM MORE DARK OR LIGHT THEN IT SHOULD BE? FAT PADS - ARE THEY PRESENT?

11-22-11 Rule Radius tilted ~110 volar on Lat. Radius tilted ~220 ulnar on AP Radial Styloid ~11mm distal to ulna Normal distal Radial anatomy should obey the 11-22-11 Rule

11mm 22 This is an image depicting the normal ulnar tilt of 22 degree (of the radius) and the radial styloid projecting approximately 11mm beyond the ulna. It is import to apply these criteria to the AP not Obligue view.

22 Normal anatomy for a lateral view has the distal radius tilted between 0-11 degrees volar. If you see it tilted dorsally - think fracture (most likely Colles) 11

3 C’s Rule Distal Radius  Lunate  Capitate appears as 3 C’s on lateral When looking at a lateral radiograph 3 consecutive C’s are depicted by radius - lunate - capitate facing distal.

22 Here is a representation of the 3 C’s

22 Here is a mal-alignment of the C’s with this Perilunate (capitate) dislocation Ortho referral

Distal Radial # Apply 11-22-11 rule Ortho referral for open, comminuted, unstable or failure to reduce, DRUJ, and NV compromise3 Generally, Smith # (volar angl.) more unstable than Colles # Research study4 Latest Research: Study by Radiologists in Edmonton from 2007 Prospective cohort of 74 pts with distal radial fractures managed conservatively Showing that sligthly inadequate reduction was not associated with clinically adverse outcomes (Disability of the Arm, Shoulder and Hand questionaire). Suggesting gross reduction and f/u is adequate management.

22 Obvious discontinuity of cortex of the distal radius on AP and dorsal agulation on lateral representing a Colles # What is the other abnormality? Fracture of Ulnar styloid - this may indicate carpal instability which we will discuss in upcoming slides.

Dorsal Barton’s Fracture 22 This is an intra-articular # of dorsal lip of radius called a Barton’s fracture associated with lunate dislocation. Dorsal Barton’s Fracture

Barton’s Fracture Intra-articular Shearing injury of dorsal (or volar) radial lip. Require ortho referral due to high-degree of instability (insertion of Brachioradialis tendon) Mechanism is more than simple FOOSH - there is usually a shearing component. This injury can occur to the Volar lip as well (termed a reverse Barton’s #) Require ortho referral due to instability.

Scaphoid # Most commonly # carpal bone (60-70%) Axial loading 70-100% sensitive (better than snuff box tenderness) Evidence suggests below elbow cast with neutral wrist & thumb free is adequate3 Refer if >1mm displaced or comminuted Follow up within 1 week is crucial. Axial loading is superior to snuff-box tenderness for identification on exam. We used to put everyone in thumbspica casts, but evid. Suggests . . .

22 This image shows Scaphoid fracture with 1-2mm displaced. Risk for AVN increases the more proximal the fracture.

22 This is the same patient - Fracture not seen as true diagnosis should be made on Ap/obligue or scaphoid view**

CT vs MRI vs Bone Scan for Scaphoid # Radiographs miss 10-20% of scaphoid # CT more sensitive and readily available3 MRI more info re: ligamentous injury but ties up MRI time. Bone scan very sensitive (72hrs - 2 weeks) but non-specific3 High resolution US may be imaging modality of choice in future (Sn100%, Sp98%) With all this information in mind - Most authors Suggest immediate CT if can’t immobilize (profess athletes) or cast and BS in 3-5 days. If BS shows fracture (SN approaches 100%) you can take the cast off.

Who is this? Terry Thomas (British actor/comedian famous for gap in front teeth)

Scapho-lunate Dissociation Forceful hyper-ext of the wrist Tenderness immediately distal to Lister’s tubercle Terry Thomas Sign or signet ring sign Ortho referral and look for Lunate/Perilunate dislocation Generally require ortho referral bc unstable and ususally associated with Lunate or Perilunate dislocation

22 Scapholunate dissociation Terry Thomas Sign (shouldn’t have more then 1-2mm space between carpals) Signet Ring Sign from rotation of scaphoid If you see either of these look for L or PL disloction on lateral

22 Volar peri-lunate dislocation

22 PRACTICE 1: FOOSH, px with axial loading of thumb What is the abnormality? SCAPHOID FRACTURE, ,1mm displaced How do you want to manage? Cast and f/u cast clinic because risk of AVN

22 PRACTICE 2: What is the abnormality? Colles # distal radius, 10 degrees dorsal angulation How do you want to manage? Closed reduction and Casting

22 PRACTICE 3: Mechanism = Forceful hyperextension What is the abnormality? Perilunate Dislocation How do you want to manage? Ortho referral Fracture of ulnar styolid is not pathopneumonic but can suggest PL dislocation

22 PRACTICE 4: Forced hyperextension What is the abnormality?Scapholunate dissociation with signet ring sign What other view do you need? Later to allign the 3 C’s

22 PRACTICE 5: What is the abnormality? Smith Fracture How do you want to manage? Closed reduction (cast in sup and extension) with close ortho f/u

22 PRACTICE 6: High-energy FOOSH with shearing mechanism What is the abnormality? Dorsal Barton’s Fracture Why ortho referral? Unstable due to disruption of BR insertion

Summary Clinical Scaphoid CT if can’t immobilize or cast & f/u bone scan in 3-5 days.4 Gross reduction of Colles # is adequate to prevent negative sequelae.1 Stability: Colles > Smith’s > Barton’s Obtain multiple views and use 11-22-11 and 3 C’s rules.

References Jaremko JL et Al. Do radiographic indices of distal radius fracture reduction predict outcomes in older adults receiving conservative treatment?Clinical Radiology. 62(1):65-72, 2007 Jan. McRae, R. Pocketbook of orthopaedics and fractures [2nd ed.]. Churchill Livingstone Elsevier, 2006. Ritchie JV. Emergency Emerg Med Clin North Am - 01-NOV-1999; 17(4): 823-42 Seitz et al. Fractures and dislocations of the wrist. Rockwell and Green’s Fractures in Adults [5 ed]. Lippincott, Williams & Wilkins, 2002. Tintnelli, JE. Emergency medicine: a comprehensive study guide [6th ed]. American College of Emergency Physicians / McGraw-Hill, New York, 2004. Pp. 1674-84.

Thank You 22