Orthopaedic Imaging: An Aid to Decision Making

Orthopaedic Imaging:Orthopaedic Imaging: An Aid to Decision Making An Aid to Decision Making

Thomas W. Grossman, Jr., M.D., FACSThomas W. Grossman, Jr., M.D., FACS

Watertown OrthopaedicsWatertown Orthopaedics

Medical Decision Making is a TriadMedical Decision Making is a Triad

History – from patients/recordsHistory – from patients/records Physical ExaminationPhysical Examination Confirming Studies – Imaging, Labs, etc. Confirming Studies – Imaging, Labs, etc.

ImagingImaging

X-rayX-ray UltrasoundUltrasound CT ScanCT Scan MRIMRI Nuclear MedicineNuclear Medicine

X-RAYX-RAY

Radiation SourceRadiation Source Patient ExposedPatient Exposed Capture ImageCapture Image Interpret Image Interpret Image

X-RAYX-RAY

Ionizing Radiation Ionizing Radiation Radiation damages cellsRadiation damages cells No limit on medical radiation exposureNo limit on medical radiation exposure Limits on non medical radiation exposure Limits on non medical radiation exposure

X-RAYX-RAY

Patient Blocks Transmission of RadiationPatient Blocks Transmission of Radiation Soft tissues LessSoft tissues Less Bones MoreBones More

X-RAYX-RAY

Capture ImageCapture Image FilmsFilms DigitalDigital

X-RAYX-RAY

Interpret ImageInterpret Image RadiologistRadiologist Orthopaedist Orthopaedist

X-RAYX-RAY

Best for:Best for: Hard tissue Hard tissue BonesBones Often combined with other imagingOften combined with other imaging

X-RAYX-RAY

Fibula FractureFibula Fracture

X-RAYX-RAY


X-RAYX-RAY


X-RAYX-RAY


X-RAYX-RAY

Femur FractureFemur Fracture

ULTRASOUNDULTRASOUND

Sound SourceSound Source Patient ExposedPatient Exposed Image CapturedImage Captured Interpret Image Interpret Image


Sound SourceSound Source SonarSonar Can’t hearCan’t hear TransducerTransducer


Patient blocks some sound waves Patient blocks some sound waves Transmits othersTransmits others


Capture ImageCapture Image FilmFilm DigitalDigital


Interpret imageInterpret image RadiologistRadiologist


Determines Solid or Not SolidDetermines Solid or Not Solid Limited UseLimited Use

Rotator CuffRotator Cuff Knee CystsKnee Cysts Deep Vein Thrombosis (blood clots)Deep Vein Thrombosis (blood clots) Pediatric hips (DDH)Pediatric hips (DDH)


Rotator CuffRotator Cuff





CT SCANCT SCAN

Computerized Axial Tomography Computerized Axial Tomography Similar to X-Ray except in slicesSimilar to X-Ray except in slices

CT SCANCT SCAN

Radiation source rotates around patientRadiation source rotates around patient Image capture rotates around patientImage capture rotates around patient Computer collects and formats imagesComputer collects and formats images Reformatting after the exam is possibleReformatting after the exam is possible

CT SCANCT SCAN

Best For:Best For: 3 dimension anatomy3 dimension anatomy SpineSpine ShoulderShoulder HipHip Fractures in jointsFractures in joints

Hard TissuesHard Tissues

CT SCANCT SCAN

CT SCANCT SCAN

HipHip

CT SCANCT SCAN

HipHip

CT SCANCT SCAN

HipHip

MRIMRI

Non Radiation cross section imagingNon Radiation cross section imaging Rapid cycling of powerful magnetic field creates Rapid cycling of powerful magnetic field creates

images (all atoms are weak magnets)images (all atoms are weak magnets)

It finds water!It finds water!

MRIMRI

Images reflect water contentImages reflect water content Bones OKBones OK Soft Tissues ExcellentSoft Tissues Excellent

MuscleMuscle TendonTendon LigamentLigament DiscsDiscs NervesNerves Blood vesselsBlood vessels

MRIMRI

KneeKnee

MRIMRI

MRIMRI

MRIMRI

ShoulderShoulder

MRIMRI

MRIMRI

MRIMRI

NUCLEAR MEDICINENUCLEAR MEDICINE

Physiology – what is the body doingPhysiology – what is the body doing Ionizing Radiation InjectedIonizing Radiation Injected Patient emits radiation (delayed)Patient emits radiation (delayed) Image capturedImage captured


Technetium - binds to bonesTechnetium - binds to bones Indium- binds to white blood cellsIndium- binds to white blood cells


Detects ActivityDetects Activity Bone is a living structure Bone is a living structure

FractureFracture CancerCancer InfectionInfection

Does not always specify why activity occursDoes not always specify why activity occurs


Dual Isotope StudiesDual Isotope Studies TechnetiumTechnetium Indium Indium

Detection of InfectionDetection of Infection




Orthopaedic ImagingOrthopaedic Imaging

What Studies?, When?What Studies?, When? X-Ray – common starting pointX-Ray – common starting point

- Imaging bonesImaging bones

- UltrasoundUltrasound- Solid or cystSolid or cyst

- CT – 3D anatomy – joints & spineCT – 3D anatomy – joints & spine- MRI – soft tissue & edemaMRI – soft tissue & edema- Nuclear Medicine – What are the cells doing?Nuclear Medicine – What are the cells doing?

Health & Medicine

Orthopaedic Imaging: An Aid to Decision Making