Radiologic Eval of Bone Fx & Pathological Fx Flashcards
Describe alignment
- General skeletal architecture: size, #, congenital anomalies, absence of bones, deformities
- Contour of bone: IN/EX irregularities, cortical outline of bone, bony outgrowth of spurs, breaks in continuity of cortex
- Alignment of bones to adjacent bones: fx, dislocation, subluxation
Describe bone density
- General bone density: assess the shade of grey, look for sufficient contrast b/w bone & soft tissue, look for sufficient contrast within the bone
- Textual abnormality: fluff, smudge, coarsening
- Local density changes: sclerotic changes (normal, excessive, reactive)
Describe cartilage space
- Cartilage is full of water, images on radiograph are radiolucent
- Evaluate the joint space width: decreased space implies cartilage or disk is thinned down due to degenerative process
- Subchondral bone: increased sclerosis = OA, erosions = RA/gout
- Epiphyseal plates: position, size, & smooth margins
Describe soft tissue
- Muscles: wasting
- Fat pads/fat lines (wrist/elbow)
- Joint capsule
- Periosteum: solid = fx healing, chronic OM; laminated = repetitive or Ewing Sarcoma; speculated/sunburst = malignant bone
- Gas, foreign bodies, calcification
What is the radiologic report
- Attempts to link radiologic signs with pt Hx & exam
- Provides a standard of comparison with previous exam
- Permanent record
- Provides important indications & contraindications for medical intervention
- Research
- Communication b/w healthcare professionals
Describe the primary trauma survey: Protocol Series
- Performed in ER
- CT often utilized to screen for major organ injury & Fx (time saving practice)
- Examples: Cross table lateral views of cervical spine (assess gross instability/Fx/dislocations); Anteroposterior (AP) chest (assess for hemothorax, pneumothorax, pulmonary contusion); AP pelvis (assess for Fx, hemorrhage)
Radiographic signs of fracture
- Cortical disruption
- Change in shape of bone
- Double density sign: 2 densities instead of 1
- Avulsion fragment
- Lucent line
- Abnormal fat pad signs
- Linear region of sclerosis
- Alteration of smooth surfaces
- Displaced bone
Categories of fractures
- Traumatic
- Stress/fatigue fracture
- Insufficiency fracture: deficient elastic resistance or weakened by decreased mineralization
- Pathologic fracture: bone abnormally fragile by neoplastic or disease
Other conditions besides fractures that can be seen on radiograph
- Accessory bones: found in the foot>wrist>shoulder
- Epiphysis/epiphyseal plates
- Juxta-articular calcification: calcium deposits near joint
- Multipartite conditions: bipartit patella/scaphoid
- Nutrient foramina: oblique radiolucency in shafts of long bones
- Sesamoids: metacarpal & tarsal heads, fabella, pisiform
Elements of fracture description
- Anatomical site & extent of fracture
- Type of fracture: complete/incomplete
- Alignment fracture fragments
- Direction of fracture line
- Presence of special features (impact/avulsion)
- Associated abnormalities (dislocation)
- Articular involvement
- Classification schemes/labels
- Physician name/other name
- Typically will be a combination of terms with non standard
Define a comminuted fracture
- multiple fragments
- more than the normal two pieces from a fracture
Long bone fracture biomechanics Force = Pattern
- Tapping = transverse fx
- Crushing = comminuted fx
- Penetrating = comminuted fx
- Bending = transverse fx
- Torsion = spiral fx
- Compression + bending = oblique/transverse or butterfly fx
- Compression +bending + torsion = oblique
- Traction = avulsion
Describe osteomalacia
- a disease that weakens bones & can cause them to break more easily
- a disorder of decreased mineralization which results in bone breaking down faster than it can re-form
- occurs in adults
- in children inadequate concentrations of Vit D may cause rickets
Describe an impaction fracture
- compression forces in axial loading
- predominately occurs in cancellous bone
Describe an avulsion fracture
- tensile loading of the bone Ie. ligaments, tendons
Describe compression fracture
- compression of vertebrae between inferior & superior adjacent vertebrae
Describe a depression fracture
- surface of one bone driven into another Ie. tibial plateau fracture
Fractures in children growth plates (Salter Harris Fractures)
- Normal: epiphysis (top), epiphyseal growth plate (middle), metaphysis (below the growth plate)
- Type I = fracture straight across the growth plate (horizontal)
- Type II = fracture starts in the growth plate and exits at the metaphysis
- Type III = fracture starts in epiphysis and exits through the growth plate
- Type IV = fracture goes through the epiphysis, epiphyseal growth plate, and metaphysis
Clinical exam for slipped capital femoral epiphysis (SCFE)
- Pediatric pathology
- restricted IR with PROM
- increased hip ER PROM
- limping
- vague pain in the hip, knee, or thigh
- knee pain can be referred
- groin pull is rare in children
Describe a greenstick fracture
- Seen in children <10 y/o
- Incomplete fracture
- Mid-diaphyseal
- Forearm/lower leg
- Bone is bent/curved
Describe nursemaid’s elbow
- subluxation of the radial head into the annular ligament, which usually spontaneously or easily reduces
- pull on extended pronated arm
Describe reduction of closed fractures
- No surgical incision is made
- Bones are guided back into position via manipulation, traction, or both
- Tissue tingle allows fracture to be reduced & when tensioned wll help to stabilize the fracture
- Non-displaced will require no reduction
How to name fracture displacements
- you name it by the distal piece
When is open reduction required
- Closed methods have failed
- Closed methods are known from experience to be ineffective
- Articular surfaces are fractures & displaced, & perfect alignment is necessary for joint function
- Fracture is secondary to metastasis
- There is an associated arterial injury
- Multiple injuries are present
Stages of fracture healing
- Cellular stage: hematoma & granulation tissue
- Vascular stage: revascularization & bony resorption
- Primary callus: fibrocartilage proliferation (soft callus)
- Bony callus: hard callus
- Mature callus: compact bone at fracture site
Describe creeping substitution
- direct osteoblastic activity at the fracture site with no callus formation if fragments are in close contact
- termed primary bone union
- Ex: surgically compressed bone healing
Factors that effect healing
- Age
- Degree of local trauma or bone loss
- Type of bone involved
- Degree of immobilization
- Infection
- Local malignancy
- Radiation or avascular necrosis
- Hormones
- Exercise/modified tension along the line of stress
Complications in fracture healing
- Delayed union: pathological/adverse factors
- Slow union: non-pathological/age/location
- Nonunion (bone repair has stopped): delayed union can create nonunion
- Malunion: angular or rotary deformity persists
- Pseudoarthrosis (false joint)
- Osteomyelitis (infection)
- Avascular necrosis
Complications in adjacent tissues
- Soft tissue injury
- Arterial injury
- Nerve injury
- Compartment Syndrome (5 P’s)
- Fat embolism (similar to a pulmonary embolism)
- Hemorrhage (especially in pelvic fractures)
What are the 5 P’s of compartment syndrome
- Pain: deep poorly localized
- Paresthesia
- Paralysis: permanent damage likely
- Pallor: distal to the compartment involved
- Pulselessness
Importance of the clinical history & evaluation
- Patient history & clinical exam prevent a missed fracture
- Trauma = fracture
- Acute point tenderness to palpation over fracture site is reliable
- Use CDRs
- Rule: if it acts like a fracture but radiographs are negative, treat it as a fracture (immobilize) & reevaluate with radiographs in 1-2 wks
Commonly missed high risk fractures on radiographs
- C1-C2 fx
- C6-C7 fx
- Vertebral body fx secondary to osteoporosis
- Scaphoid fx
- Triquetrum fx
- Galeazzi fx (distal 1/3 of radius)
- Distal radius fx + carpal injury
- Monteggia fx (proximal ulna fx)
- Radial head fx
- Femoral neck fx
- Acetabulum fx
- Sacrum fx
- Pelvic ring fx
- Tibial plateau fx
- Tibial spine fx
- Second fx
- Patella fx
- Maisonneuve fx
- Calcaneus fx
- Talus fx
- Thoracolumbar fx + calcaneus fx
Describe pathologic fractures
- Bone weakened by a pathological process
- Systemic: Congenital (osteogenesis imperfect & osteopetrosis) & Acquired (osteoporosis & Paget’s disease)
- Local: tumor, infection, disuse, sequelae or irradiation
What are the 6 basic categories of skeletal pathology for fractures
- Congenital
- Inflammatory
- Neoplastic
- Metabolic
- Traumatic
- Vascular
- Miscellaneous
11 predictor variables of bone tumors
- Behavior of the lesion
- Bone/joint involved
- Locus within a bone
- Patient demographics: age, gender, ethnicity
- Margin of the lesion
- Shape of the lesion
- Joint space involvement
- Bony reaction
- Matrix production
- Soft tissue changes
- Patient history
Describe the behavior of a lesion
- Osteoblastic: creates new bone formation
- Osteolytic/osteoclastic: Geographic destruction (areas of bone destroyed/radiolucent areas; sharp borders = benign lesion); Moth eaten (several small holes throughout the bone; ragged boarders = metastatic); Permeative destruction (fine destruction of the Haversian system; poorly defined boarders = metastatic)
- Mixed
Describe margin of the lesion
- sharp & clearly defined with sclerotic borders = slow growing/benign
- poorly defined with no sclerosis = fast growing/malignant
Describe shape of lesion
- Longer than it is wide = slow growth/benign
- Wider than it is long = fast growth/malignant
- Cortical breakthrough = malignant
- No cortical breakthrough = benign
Describe joint space involvement related to bone tumors
- Infections & inflammation invade the joint space
- Bone tumors generally do not cross joint spaces
Describe bony reaction
- Sclerosis: new bone growth
- Buttressing: osteophyte formation for stabilizing a joint
- Periosteal reaction: interrupted suggests tumor & uninterrupted = benign
Describe matrix production
- A matrix is tissue formed by primary bone neoplasms
- Chondroid = cartilaginous
- Osteoid = bone
- Mixed
Describe osteomyelitis
- Soft tissue edema, loss of tissue planes (blurring)
- Lytic lesion = increased radiolucency = cortical & cancellous destruction
- Sequestra = isolated bone segments of dead bone & immature periosteal bone
Describe infectious arthritis
- Soft tissue swelling
- Radiolucency of pain at periarticular regions
- Joint space narrowing
- Subchondral bone erosion