CT Scans are Essential: You will Fail Otherwise J. W . W. . - - PowerPoint PPT Presentation

CT Scans are Essential: You will Fail Otherwise

• J. W

. W. . Thomas By Byrd, MD MD

Min Mini-Pane nel: Imaging ng S Showdow

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Orthop thopae aedic S c Summit 2 t 2017 17 - Evolving ng T Techni hniques ues Las V Vegas as, N Nevad ada Decem cember er 8th

th, 201

2017

• Don’

Don’t g get a et a CT CT scan can on

• n ev

ever eryone

• Rare

rely n necessary t to ma make decis ision a

• n about

ut s surg rgery ery

– Tha hat’s b based on

• n nume

numerou

• us ot
• the

her fact actors… s…

• Once d

e decis ision f ion for surg rgery ery h has been ma made, C CT helpf lpful f for: r:

– Sus Suspected c cont

• ntribut

ution of n of FA FAI (Most c

t cas ases)

– Occa casi sionally, y, t to rule o e out/asse assess ss componen ent o

• f dysp

splasi asia t a that at m might contraindicat cate a e arthrosc scopy

• Ample l

le literat rature t ure to support:

• rt:

– Inad adequac acy y of plai ain r rad adiography i y in asse sessi ssing c complex ex t three ee dime mens nsional ana natom

• my of
• f FA

FAI – Superio iority ity o

• f CT im

imagin ing ( (3D r

D rec econs)

The Crossover Sign Overestimates Acetabular Retroversion

Clin Orthop Rel Res 2013; 471(8)2463-2470.

Zaltz I, Kelly BT, Hetsroni I, Bedi A

Standardized AP Radiographs Do Not Provide Reliable Diagnostic Measures for the Assessment of Acetabular Retroversion

J Orthop Res 2012; Sep:1369-1376.

Wassilew GI, Heller MO, Diederichs G, Janz V, Wenzl M, Perka C

Novel CT-based 3-Dimensional Software Improves the Characterization of Cam Morphology

Clin Orthop Rel Res 2013;471:2484-2491.

Milone MT, Bedi A, Poultsides L, Magennia E, Byrd JWT, Larson CM, Kelly BT

• Few a

art rtic icles t try ry t to imp imply c compa mpara rable ro role le f for p r pla lain in ra radiogr graph phy:

– Methodology w y weak eak – Clinical al r relev evan ance ce marginal

Inter- and Intra-observer Agreement of FAI Parameters Comparing Plain Radiographs and Advanced, 3D CT-generated Hip Models in a Surgical Patient Cohort

Knee Surg Sports Traumatol Arthrosc. 2014;published online September 26.

Cadet ER, Babatunde OM, Gorroochurn P, Chan AK, et al.

Do Plain Radiographs Correlate with CT for Imaging of Cam-Type FAI?

Clin Orthop Rel Res 2012; 470: 3313-3320.

Nepple JJ, Martel JM, Kim YJ, Zaltz I, Clohisy JC, ANCHOR Study Group

• At le

least a as enli ligh ghtening in g in seeming ngly ly s straig aight htforw

• rward

ard c cases es as compl mplex c cases

– Pr Prob

• bably mor

more so

• wi

with wha h what l look

• oks to
• be s

straightforwar ard, s since y ce you w would

• ther

erwise se r remai ain u unsusp specting

• Primi

rimitive 2 2D in indices t try rying t g to in interpr pret c comp mplex 3 3D anatomy my

• Move t

towards ds mo more re me meaningf gful 3 3D param ameters eters

Emerging Ideas: Novel 3D Quantification and Classification of Cam Lesions in Patients with Femoroacetabular Impingement

Clin Orthop Rel Res 2013;471:358-362.

Kang RW, Yanke AB, Orias AE, Inous N, Nho S

A Novel Method for Defining Normal Acetabular Coverage: A CT-Based Study of Asymptomatic Hips and Correlation with Conventional Radiographic Measures of Acetabular Deformity

Larson CM, Moreau-Gaudry A, Kelly BT, Byrd JWT, Tonetti J, Lavallee S, Chabanas L, Barrier G, Bedi A

Clin Orthop Rel Res, pub pending.

Radiation?

• Low

Low-dos

• se r

e radiatio iation p n protoc tocol

• l

– Les ess t than an 5 5 film h hip ser series

• Best e

t esti timate ate

• Not i

t inconsequ quen ential

Radiati tion?

• CT r

radiation ation o

• ffset b

t by o

• ther

r advant antag ages es:

– Min Minim imiz izes p pla lain in r radiographs

• Reasonabl

bly c cente tered d AP pelvis

• Frog l

g late teral a affect cted d hip

• Eas

asy to g to get r et rep eproducible v view ew

• Occ

ccasionally f fal alse e profi file

• Asse

ssessi sing d dysp ysplasi sia

• Discer

cern o n occul cult a t anter erior

• r o
• r p

poster terior

• r j

joint nt space n ce narrow

• wing

ng t that m at might c ht contr ntrai aind ndicate cate arthr thros

• scop

copy

Radiati tion?

• CT r

radiation ation o

• ffset b

t by o

• ther

r advant antag ages es:

– Eliminat ates n s need ed for r rep epea eating radiograp aphs s to get p proper o

• rien

entat ation

• Pr

Proverbi bial p prope perly c cen ente tered d AP P pel elvis, Du Dunn v view, w, etc tc.

• Ev

Everyone e emphasizes es i importance of prope perly o

• riente

ted r d radiogr graph phs; b but h t how w do y

• you
• u cor
• rrect w

whe hen you d

• u don
• n’t?
• Keep

ep s shooti

• ting

ng?

Radiati tion?

• CT r

radiation ation o

• ffset b

t by o

• ther

r advant antag ages es:

– Lessen ssens n s need ed f for intrao aoperative ve fluorosco scopy

• Ev

Everyone g gets ts wet wet

Radiati tion?

Summary

• Need

d to be min mindful in in y your decis ision t

• n to order a

er a CT scan an

– Onl nly wi with a h a pur urpos

• se
• Cle

learl rly g giv ives y you a a better interp rpretat retation o ion of comple lex t x three e dimens ensional a

• nal anatom
• my o
• f FAI p

problem lems wit ith w whic ich w we are re challe lenged

Summary ary

• Peop

People who ho say ay they they don’

• n’t

need it, I q ques estion ion whether her they they s simply d don’

• n’t k

know now w what hat they they are re n not seeing

• Freque

uently ntly s surp rpris ised ed b by i inform rmation ation gleaned aned f from C CT t that s substan tantial tially ly alt lters o

• r

r sharpe pens my my surgi gical strateg ategy

– Hard t to pred edict ct w which cases t ases those se are e goi

• ing

ng t to

• be…

Summary ary

• Goo

Good Luc Luck!...

Summary ary

“No No one

• ne want

ants an an unl unluc ucky s sur urgeon…”