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					     Nuclear Medicine
     in the Evaluation
         of Trauma
Materials for medical students

         Helena Balon, MD
       Wm. Beaumont Hospital
        Royal Oak, MI, USA
         Charles University
       3rd School of Medicine
       Dept Nucl Med, Prague
Radionuclide methods in traumatology
n   Musculoskeletal trauma
    u   Bone scan
n   Trauma to internal organs (hematoma, laceration,
         fracture, perforation, leaks)
    u   Renal scan
    u   Myocardial scan
    u   Hepatobiliary scan
    u   (Liver / spleen scan) - CT preferred
    u   (Testicular scan) - US preferred
n   Head trauma
    u   CT preferred
    u   Cerebral perfusion scan - brain death
    u   Cisternography - CSF leak
Bone scan in trauma

n   Very sensitive
n   Detects areas of abnormal bone turnover
n   Shows areas that need further radiol.evaluation
n   Provides objective evidence of disorder
    when X ray negative
Bone scan
n   Tracers: diphosphonates (Tc-99m MDP, HDP)
n   Dose:     500-900MBq
n   Tracer localization (chemisorption onto surface
    of bone trabeculae) depends on:
     u blood flow

     u capillary permeability

     u bone metabolism (activity of osteoblasts,
       osteoclasts, new bone formation)
Bone scan

n   Patient preparation
     u Pre-test: none

     u Post-injection: good oral hydration

     u Frequent voiding

     u Perchlorate p.o. preinj. to decrease rad.
       dose to thyroid
Bone scan

n   Methods
    u Regular - imaging @ 2-4 hrs post injection
    u 3-phase (dynamic angiogram + blood pool +
    u Planar or SPECT

    u Whole body ANT & POST, additional views
    u Parallel hole or pinhole collimator (for small
Bone Scan in Trauma
n   Fractures & occult fx
n   Child abuse (except skull fx)
n   Stress fractures (insufficiency fx, fatigue fx)
n   Avulsion injuries
n   Shin splints
n   Bone bruises (contusion)
n   RSD (reflex sympathetic dystrophy)
n   Osteochondral lesions
Diagnosis of Fractures

n Plain X ray, X ray tomography - if neg >>>
n Bone scan
   u if neg >>> stop work-up

   u if diagnostic >>> treat

   u if more information needed >>>

n CT (subtle changes) or
n MRI (subtle changes, soft tissue trauma,
         bone bruise, precise dx of limited area)
Fractures on Bone scan

n   Acute fx
    u Positive on all 3 phases
    u Positive immediately after trauma in most pts

    u 90% sensitivity if imaged in < 48 hrs

    u If scan neg. in pts > 75y >>> repeat scan in 3-7 d

n   Bone scan remains positive for 6-24 mo
      (healing fx)
Acute compression fractures

                         80 y/o F w osteopenia
                         fell 6 wks prior
Rib fractures
Multiple fx’s

                59 F w breast ca
                MVA 10 d ago
Osteogenesis imperfecta
Bone Bruise

n   Direct trauma with disruption of trabecular
    bone but not cortical bone
n   X ray - negative
n   Bone scan - 3-phase positivity
n   MRI - bone marrow involvement
Leg & Foot
Shin / thigh splints
n   Continuous spectrum from shin splint to stress fx
n   Stress related periostitis along muscle insertion sites
    (soleus, tibialis posterior, adductor longus/brevis, gluteus max)
n   X ray - negative
n   Bone scan
    u   Flow, blood pool - normal
    u   Delay- vertical, linear uptake along
         posteromedial tibial cortex (mid- or distal 1/3)
         medial or lateral femoral cortex (proximal 1/3)
Shin Splints
Shin splints, thigh splints
Thigh splints - mechanism
Stress Fractures
n   Fatigue fractures
     Abnormal stress on normal bone
     (jogging, gymnastics, skating, military)

n   Insufficiency fractures
      Normal stress on abnormal bone
     (osteoporosis, osteomalacia, RA, HPT, steroids,
     radiation Rx)
Stress fractures
n   Pathophysiology - repetitive microtrauma (athletes)
n   Symptoms - pain, swelling
n   Common locations:
     u Tibia - proximal or distal 1/3

     u Fibula - distal 1/3
                       nd  rd
     u Metatarsals (2 , 3 )

     u Tarsal bones (calcaneus, navicular)

     u Femoral neck

     u Inferior pubic ramus

     u Lower lumbar spine (spondylolysis)
Stress fractures
n   X ray may be initially negative (2-4 wks)
n   Bone scan, MRI – positive earlier
n   Bone scan        3-phase positivity
    u   Flow         + for ~ 1 mo
    u   Blood pool   + for ~ 2 mo
    u   Delay        + for ~ 9-12 mo
n   Rx - restrict sports for 4-6 wks
Stress fx ?
Stress fractures
Metatarsal stress fracture
stress fracture
Metatarsal stress fx
Plantar fasciitis
n Heel pain
n Post-traumatic inflammation of plantar
  ligament due to
    u athletic overuse
    u prolonged standing

    u walking on hard surface

n   Bone scan
        Focal blood pool + delayed uptake
        in inferior posterior calcaneus
Plantar fasciitis
Achilles tendonitis
Impingement syndromes
n   Posterior impingement sy (os trigonum sy)
    u Excessive repeat plantar flexion (compression
      between posterior calcaneus & posterior tibia)
    u Ballet dancers, gymnasts

n   Anterior impingement sy
    u Excessive repeat dorsal flexion >>> hypertrophic
      spur on dorsum (talus & anterior tibia)
    u Ballet dancers, gymnasts, high jumping
Posterior impingement syndrome
     (os trigonum stress fx)

Hip & Pelvis
Femoral neck stress fracture

n   Thigh or groin pain in athletes
n   Must distinguish femoral neck stress fx
    from pubic ramus stress fx
n   Must treat / immobilize early to prevent
    complete fx, AVN
Femoral neck Fx

                  76F w L groin pain
                  X ray neg
X ray
2 weeks later
Intertrochanteric fracture

      93 F, fall 6 days ago, Rt hip pain
IT fx
Avascular necrosis (AVN)
n   Etiology
    u trauma (fx)
    u steroids, alcohol abuse

    u pancreatitis, fat embolism

    u vasculitis, SS disease

    u idiopathic

n Pathophysiology: bone ischemia
n Diagnosis
    u MRI most sensitive
    u bone scan useful
n   Common locations
    u Femoral head (Legg-Perthes in children)
    u Carpal (scaphoid, lunate), tarsal (talus)

    u Long bones, ribs in SS

n   Bone scan
    u Initially “cold”
    u Revascularization starts in 1-3 wks, from
      periphery, diffusely “hot”, lasts for months

       50 M w fall a few weeks ago
IT fx + AVN

Sacrococcygeal Fx

     ANT            POST
Sacral insufficiency fx

       ANT                        POST
             79 F fell 1 mo ago
             (“Honda” sign)
Pelvic fractures

                   4 days
                   post fall

                   1 month
Spine trauma
n   Stress fx of posterior vertebral elements
    (pars interarticularis) due to repetitive trauma
n   Teenagers, young adults
n   Hyperextension sports
       (gymnastics, diving, weight lifting, soccer,hockey)
n   Genetic predisposition?
n   L5 > L4 > L3
n   Frequently bilateral >>> spondylolisthesis
n   X ray
      Normal or sclerosis, later lucency 2º fx
n   Bone scan
       increased uptake in pars interarticularis
       SPECT better than planar
n   Rx – discontinue activity
Pars interarticularis defect

                               14 y/o F
                               basketball player
                               trauma 1 mo prior
Pars defect
Transverse process fracture

   planar             SPECT

                              CNM 2001:863
Hand & Wrist
Wrist fractures
n   Scaphoid fx - most common
    u 70-80% carpal fx
    u Fall on outstretched hand

    u Common complications - AVN, non-union

n   Hook of hamate fx
    u   Direct injury from handles (tennis, golf, baseball)
n   Radial / ulnar styloid fx
fall, injured Rt wrist
Fracture of radius + scaphoid

      S/P fall, suspect scaphoid fx
                X ray neg.
Scaphoid Fx

              14 y/o M
              fell 6 wks ago,
              X ray negative
Hook of the hamate fracture

             R wrist pain
Hook of the hamate injury - mechanism
Reflex Sympathetic Dystrophy
(Sudeck’s atrophy, Shoulder-hand sy, Causalgia,
Chronic regional pain sy)

n   Sympathetically mediated disorder
    (vasomotor instability)
n   Etiology
    uTrauma (blunt, fracture)
   u MI
   u Stroke/CVA
   u Infection
   u Idiopathic

n Symptoms: exquisite pain, tenderness, edema,
  skin changes, locally warm or cold UE or LE
Reflex Sympathetic Dystrophy (RSD)
n   Bone scan
    u   Early stage: 3-phase positive
    u   Later stage (> 6 mo): only delayed phase posit.
    u   Delayed phase MDP: diffuse increased uptake in entire
        limb, “periarticular accentuation”
        in small joints
    u   Children: often all 3 phases    or
    u   Sensitivity: 60-95%
n   X ray
    u   Periarticular ST edema
    u   Late changes- bone resorption, osteopenia
Reflex sympathetic dystrophy

   73 F w Rt hand/wrist pain
   no trauma
Non-accidental injury

                        1 mo old baby
                        w intracranial
                        Lt parietal fx
  Muscle trauma

     weight lifting
                      CNM 2001: 344
Muscle uptake (Rhabdomyolysis)

                         pt w Ewing sarcoma,
                         s/p BKA,
                         walking on crutches
   Trauma to
internal organs
    Hepatobiliary Scan
n   Tc-99m IDA (disofenin, mebrofenin)
     u   dose ~ 150-250 MBq i.v.
     u   imaging of liver, abdomen, pelvis over 1 hr
     u   delayed images if 1st hr negative
n   Bile leak - activity anywhere in peritoneal cavity
n   Common after laparoscopic cholecystectomy
n   Usually seals off spontaneously
n   Leak clin. more significant if no transit into bowel
    seen (needs surgical intervention)
Bile leak
Liver - Spleen Scan

n   Tc-99m sulfur colloid
    u   dose ~ 150-250 MBq i.v.
    u   SPECT imaging better than planar
n   Parenchymal defects
    u   laceration, rupture, hematoma
n   Splenosis
    u   splenic implants on peritoneum following spleen rupture

MVA 30 y ago,
S/P splenectomy
                  Tc-99m S.C.
Pleuroperitoneal leak

           ANT                       Rt LAT

        Pt. on peritoneal dialysis
Renal Scans
n   Tc-99m MAG3 or DTPA
    u   ~ 100-300 MBq
    u   Dynamic images over 20-30 min
    u   Assessment of perfusion, function, leaks
n   Tc-99m DMSA
    u   ~ 150-250 MBq
    u   Static images @ 2-4 hrs post injection
    u   High resolution needed for renal morphology
         t   pinhole, SPECT
    u   Parenchymal defects - laceration, rupture, hematoma
    u   Extrinsic defects - perinephric / retroperiton.
               Urine leak

CNM 2001:724
Testicular scan
n   Indications:
     u Acute torsion

     u Delayed torsion

     u Epidymitis / orchitis

n   Tc-99m pertechnetate
n   Flow + immediate static images
n   “Donut sign”
     u Late torsion

     u Abscess

     u Trauma (hematoma)

     u Tumor

n In-111 DTPA intrathecally
n CSF leak - paraspinal (meningeal tears)
n CSF rhinorrhea, otorrhea
   u imaging

   u counting nasal pledgets for radioactivity

   u pledget / plasma ratio
Cerebral perfusion
n Tc-99m HMPAO or ECD
   u dose ~ 800 MBq

n Post-traumatic perfusion defects
n Assessment of brain death - role of NM
   u no flow

   u no parenchymal uptake
Head Trauma
? Brain death?

                 15 y/o F with
                 intracranial bleed

Brain death

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