ASSESSMENT AND RADIOLOGY OF DISTAL

RADIUS FRACTURE

By Dr Susanta kumar khuntiaJR ORTHOPEDICS

Moderate by Dr Anil k. SahuAsso.prof essor

dept. of orthopedicsMKCG MC,Berhampur odisha

Distal Radius Fractures

Common injury

Potential for functional impairment and frequent complications

HISTORY

HISTORY

Barton 1838 described wrist subluxation consequent to intraarticular fracture of radius which could be dorsal or volar.

Smith described fracture of distal radius with ‘forward’ displacement.

Advent of X rays at the end of nineteenth century contributed much to the understanding of different patterns of injury.

Anatomy scaphoid and lunate

fossa Ridge normally exists

between these two

sigmoid notch: second important articular surface

triangular fibrocartilage complex(TFCC): distal edge of radius to base of ulnar styloid

Cross-sectional anatomy of the radial metaphysis. Note that the dorsal surface is much more irregular than the palmar surface. The V-shape dorsally caused by Lister's tubercle (arrow) makes it difficult to contour a plate to fit the dorsum of the radius.

Applied anatomy Jakob and his co-authors interpreted the wrist as

consisting of three distinct columns, each of which is subjected to different forces and thus must be addressed as discrete elements

The radial column, or lateral column

The radial column consists of the scaphoid fossa and the radial styloid. Because of the radial inclination of 22 degreees, impaction of the scaphoid on the articular surface results in a shear moment on the radial styloid causing failure laterally at the radial cortex. The radial column, therefore, is best stabilized by buttressing the lateral cortex

The intermediate column

The intermediate column consists of the lunate fossa and the sigmoid notch of the radius. The intermediate column may be considered the cornerstone of the radius because it is critical for both articular congruity and distal radioulnar function. Failure of the intermediate column occurs as a result of impaction of the lunate on the articular surface with dorsal comminution. The column is stabilized by a direct buttress of the dorsal ulnar aspect of the radius

The medial column

The ulnar column consists of the ulna styloid but also should include the TFCC and the ulnocarpal ligaments

Incidence

One sixth of all fractures treated in the Emergency Room

Bimodal distribution less than 30 years (70% men) over 50 years (85% women)

Different characteristics of fracture depends on

Position of hand (60 -90 degree) Type of surface Velocity of force Quality and strength of bone

Pathomechanism of distal radius fracture

The theory of compression impaction by dupuytren in 1834

The avulsion theory in 1852 The incurvation theory by mayer in

1940

Pathomechanism of posteriorly displaced fracture

The usual cause is fall on the hyperextended wrist

A)The theory of compression impaction when is hyperextended proximal carpal bones come and impact dorsal aspect of radius and body weight is transmitted through long axis of radius to distal end and compression occur at dorsal aspect of distal radius leading to fracture

B)The avulsion theory-The indirect force presented by the body weight are transmitted through humerus,ulna,radius and then a volar wrist ligaments.Then fracture occured by avulsion mechanism applied by the tensile forces transmitted by the volar wrist ligaments.

CONTINUE....

The Incurvation theory-depends on position of the hand,the extent of the area of impact,the magnitude of the applied force

Commonly in elderly age group due to osteoporosis bone and high incidence of fall .

Pathomechanism of anteriorly displaced fracture

A)Axial stress on the radius with a backward fall on the palm of the hand.Wrist in extension and without displacement of the body over the hand.The radius incurved sustains compression force on the volar cortex and tensile forces on the dorsum

B)Forced flexion where direct compression stress on volar cortex combined with traction exerted by the dorsal ligament

Diagnosis: History and Physical Findings

History of a FOOSH

Physical FindingsINSPECTION. Visible deformity of the

wrist, with the hand most commonly displaced in the dorsal direction.

. Dinner fork deformity occurs in colles and dorsal barton farcture .

. Gardenspade deformity occurs in smith or palmar bartons fracture

. Dorsal aspect of hand and wrist are usually swollen and ecchymosed

PALPATION The wrist should be examined for tenderness

Radial and ulnar styloids at same level (laugier sign)

Movement of the hand and wrist are painful.

Adequate and accurate assessment of the neurovascular status of the hand is imperative, before any treatment is carried out

Median nerve function and flexor and extensor tendon action should be tested

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associated fractures of either the radial head or supracondylar humerus.

An effort should also be made to identify an ipsilateral scaphoid fracture, which may direct the surgeon to consider operative versus nonoperative management.

attention should be directed to the extensor

pollicis longus, which may be injured acutely at Lister's tubercle or may present with a late spontaneous rupture.

Radiology

DIFFERENT X RAY VIEWS:.PA View.Lateral view.Oblique view.Tilted lateral view.Traction view

Continue X-ray AP VIEW

For extraarticular asses 1)radial shortening/communition 2)ulnar styloid fracture location

For intraarticular asses 1)depression of the lunate facet 2)gap b/n scaphoid and lunate facet 3)central impaction fragements 4)interruption of the proximal carpal row

X-ray lateral view For extraarticular

fracture asses1)palmar tilt 2)extent of metaphyseal communition 3)displacement of the volar cortex

4)scapholunate angle 5)position of the DRUJ

OBLIQUE VIEW Assessing radial comminution Split or depression of radial styloidTILTED LATERAL VIEW. Lunate facetTRACTION VIEWS.Help to plan out the management

RADIOLOGY

Radial inclination (23deg)

Volar inclination (11deg)

Radial length (11mm)

Ulnar variance (+ / - 1mm)

Radial Inclination• Inclination of radius towards the ulna• measured by the angle between a

line drawn from the tip of the radial styloid to the medial corner of the articular surface of the radius and a line drawn perpendicular to the long axis of the radius

• Average : 23 degree (13-30)

Radial Length• Inclination of radius towards the ulna• measured by a line drawn

perpendicular to the long axis of the radius and tangential to the most distal point of the ulnar head and a line drawn perpendicular to the long axis of the radius and at the level of the tip of the radial styloid

• Average : 11 mm (8-18)

Dorsal/Palmar tilt• A line is drawn connecting the most

distal points of the volar and dorsal lips of the radius. The dorsal or palmar tilt is the angle created with a line drawn perpendicular along the longitudinal axis of the radius

Ulnar variance• A line parallel to the medial corner of the

articular surface of the radius and a line parallel to the most distal point of the articular surface of the ulnar head, both of which are perpendicular to the long axis of the radius

• Measure of radial shortening• Normal : -2 to +2 mm

Carpal Malalignment• In lateral view, one line is drawn along the long

axis of the capitate and one down the long axis of the radius. If the carpus is aligned, the lines will intersect within the carpus. If not, they will intersect outwith the carpus.

• More than 2 mm of intra articular step off leads to articular incongruity

TEARDROP ANGLE & AP DISTANCE

Angle between central axis of teardrop (u shaped outline of lunate facet) and radial shaft

< 45 degree indicate displacement of lunate facet

AP distance is distance between apices of dorsal and volar rims of lunate facet

Also measure articular incongruity

1: Line connecting dorsal and volar tip of lunate

2: Line perpendicular to lunate

3: Line along axis of scaphoid

Scapholunate angle measured between lines 2 and 3

(normal 47 ± 15 degrees)

Computed TomographyIndications:

Intra-articular fxs with multiple fragments

centrally impacted fragments

DRUJ incongruity CT scan:For

conformation of occult fracture like intraarticular fracture of lunate fossa

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MRI scan:For evaluation of suspected soft tissue injuries

1. Flexor or extensor tendon injuries

2. Median nerve injuries3. Early diagnosis of

necrosis of sacphoid or lunate

4. Perforation of TFCC5. Rupture of carpal

ligaments

Classification

A)classification based on different fracture types

1)Colles fracture/pouteau’s fracture 2)Smith’s farcture/reverse colles fracture 3)Barton’s fracture 4)Chauffer’s fracture 5)Lunate load or die punch fracture

Colles fracture It is an extraarticular fracture occurs at

corticocancellous junction of distal end of radius within 2cm from the articular surface

It may extend into DRUJ with six displacements1. Impaction2. Lateral displacement 3. Lateral rotation (angulation)4. Dorsal displacement5. Dorsal rotation (angulation)6. Supination.

It may often accompany fracture of the ulnar styloid which signify avulsion of the TFCC and ulnar collateral ligaments

Smith’s fracture/Reverse colles fracture

Occurs at the same level on the distal radius as a colles' fracture.

Distal fragment displaced in palmar (volar) direction with a "garden spade" deformity.

Modified Thomas Classification of Smith's Fracture:

Type I: Extraarticular Type II:Crosses into the dorsal articular surface Type III:Enters the radiocarpal joint(equivalent to

volar barton fracture dislocation)

Smith's fracture (reverse colle's or volar Barton's) typical deformity: garden-spade deformity1. Dorsal prominence of the distal end

of the proximal fragment2. Fullness of the wrist on the volar

side due to the displaced distal fragment

3. Deviation of the hand toward the radial side

Barton’s fracture It is an intrarticular fracture dislocation or

subluxation in which the rim of the distal radius dorsally or volarly is displaced with the hand and carpus

There are 2 types Dorsal barton volar barton

1. Dorsal Barton: Dorsal rim fracture of distal radius Mechanism: Fall with dorsiflexion and pronation of the

distal forearm on a flexed wrist.2. Volar Barton:Palmar rim fracture of distal radius Mechanism: It is due to palmar tensile stress and

dorsal shear stress and is usually combined with radial styloid fracture.

Volar barton Dorsal barton

Chauffeur’s fracture/hutchison fracture

It is an intraarticular fracture involving the radial styloid,the radius is cleaved in a sagittal plane and the fragment is displaced proximally.Isolated fracture of the radial styloid are fairly common from backfiring of starting handle of car

Lunate load/Die punch fracture It is an intraarticular fracture with

displacement of the medial articular surface which usually represents a depression of dorsal aspect of lunate fossa

Common Classifications

Gartland/Werley Frykman Weber (AO/ASIF) Column theory Melone Fernandez (mechanism)

Frykman Classification

Extra-articular

Radio-carpal joint

Radio-ulnar joint

Both joints

{Same pattern as odd numbers, except ulnar styloid also fractured

AO/ OTA Classification

Group A: Extra-articular

Group B: Partial Intra-articular

Group C: Complete Intra-articular

Column Theory

Rikli & Regazzoni, 1996

3 Columns: radial, intermediate, medial

Three Column Theory

Radial ColumnLateral side of radius

Intermediate ColumnUlnar side of

radius Ulnar Column

distal ulna

Radial column

Intermediate column

Ulnar column

Classification – Fernandez (1997) I. Bending-

metaphysis fails under tensile stress (Colles, Smith)

II. Shearing-fractures of joint surface (Barton, radial styloid)

Classification – Fernandez (1997)

III. Compression-intraarticular fracture with impaction of subchondral and metaphyseal bone (die-punch)

IV. Avulsion-fractures of ligament attachments (ulna, radial styloid)

V. Combined/complex - high velocity injuries

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B)Universal classification 1)Extraarticular 2)Intraarticular

C)Other types