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Lower extremity xray rounds
Heather Patterson PGY3 August 23, 2007
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Objectives Classification of fractures Practice, practice, practice!
This will NOT be: Clinical exam Management
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Hip Classification: Intracapsular Extracapsular Femoral head neck
Intertrochanteric Subtrochanteric Greater/lesser trochanter
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Hip AVN: Injuries to medal and lateral femoral circumflex arteries
After fracture the synovial fluid will lyse blood clots and prevent capillary formation needed for new bone formation/repair For exams: radiological staging of AVN: Isch causes increased pressure/edema/fibrosis. New bone masks any changes seen on Xra6y. Changes only seen on CT Bone growth looks mottled with lucencies. Femoral head look normal 3. Collapse of the femoral head. “crescent sign” Severe/complete collapse of the femoral head with irregular densities in remaining structure.
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Approach Shenton’s Line
Obturator foramen to medial surface of the proximal femur
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Approach Normal and Reverse S
Medial and lateral margins of the fem head and neck
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Approach Trabecular groups
Follow the groups starting at the femoral head
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Avulsion Often in young athletes Rapid accel/decel Snap/pop Locations:
ASIS: sartorius AIIS: rectus femoris Isch tuberosity: hamstring
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Name this fracture
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Femoral Neck Fractures
Classification: Transcervical vs subcapital Displaced vs nondisplaced Often seen with osteoporosis/mets Minimal/no injury necessaryif osteoporotic/mets Complications: AVN/nonunion
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Femoral Neck Fractures
Displaced (80%) Shortened, rotated Vascular structures disrupted Nondisplaced (20%) Subtle fractures Must use lines/trabec to see May be impacted – increased subcapital density Often seen with osteoporosis/mets Minimal/no injury necessaryif osteoporotic/mets Complications: AVN/nonunion
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Name this fracture
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Intertrochanteric fractures
Fracture runs between greater and lesser trochanter Excellent blood supply Often will be in internal rotation Int rotators attached to distal femur Ext rotators attached to proximal fragment High energy fracture in young adults (LANZ) Associated injuries ie Lspine
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Intertrochanteric fractures
Classification: 2 part
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Intertrochanteric fractures
Classification 3 part:
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Intertrochanteric fractures
Classification 4 part:
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Trochanter fractures Isolated fractures are rare
From direct force with fall or avulsion from iliopsoas
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Name this fracture
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Subtrochanteric fractures
Location: Btwn lesser trochanter and proximal 5cm of femoral shaft Often comminuted Hemodynamic instability is seen with this fracture type Elderly: falls with weak cortical bone Pathological common here Young with high energy trauyma. Often associated with abdo/chest/pelvi sinjury
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Subtrochanteric fractures
Classification: Short oblique Short oblique + commin. Long oblique Long oblique + commin. High transverse Low transverse Elderly: falls with weak cortical bone Pathological common here Young with high energy trauyma. Often associated with abdo/chest/pelvi sinjury
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Stress fractures Need high index of suspicion Symptoms:
A.M. stiffness, aching with first steps after rest, increasing pain with exercise Pain in groin or medial thigh to knee Antalgic gait, min pain with ROM except at extremes DDX large: AVN, OA, Osteo, lumbar dic, discitis, toxic synovitis, septic arthritis, bursitis, tumor, occult #, tendonitis, arterial insufficiency, DVT, SCFE, LCP,
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Dislocations High force Classification: Posterior Anterior Obturator
Inferior Central Fracture of femoral head with dislocation Dislocation classified based on location of femoral head to the acetab7ulum. High force therefore don’t forget about associated injuries Positioning: Posterior: FDI (flexed aDDucted internal rotation), shortened and greater troch/buttock unusually prominent Anterior: FBE (flexed aBducted, externally rotated)
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Fracture dislocations
Positioning: Posterior: FDI flexed aDducted internal rotation shortened and greater troch/buttock unusually prominent Anterior: FBE flexed aBducted, externally rotated Read about 2 reduction techniques – this is an xray talk so won’t belabour the clinical aspects.
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Dislocations Posterior:
Lesser trochanter superimposed on femoral shaft Small femoral head Disruption of shenton’s line in both of these dislocations
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Dislocations Anterior: Lesser trochanter in profile Large femoral head
Disruption of shenton’s line in both of these dislocations
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Practise Femoral neck, displaced
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Practise Ant hip pre and post reduction
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Practise Greater trochanter
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Practise Femoral neck
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Practise Bilat dilocation L is posterio R is obturator
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Practise Intertroch. At a minimum this is a 2 part but more likely 3-4 part. Need further imaging to deliniate.
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Practise Subtroch plus trochanter plus acetabular plus pelvis
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Practise intertroch
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Practise normal
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Practise Nondisplaced femoral neck. Suspect this because of an abnormal S curve
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Practise Femoral neck
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Practise Posterior dislocation
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Practise Sub troch plus femoral shaft
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Sub troch plus femoral shaft
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Type 3 tibial plateau
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Name this fracture Sub troch plus femoral shaft
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Ottawa Knee rules X-ray knees with knee injury and one or more of:
>55 years old Tenderness to palpation of head of fibula Isolated tenderness of patella Inability to flex knee to 90 degrees Inability to bear weight both immediately and inability to take four steps in ED Uncommon – high velocity injuries ie MVC and falls
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Ottawa Knee rules Exclusion criteria: Isolated skin injuries
Referred patients from another ED or clinic Injury >7 days old Patient returning for re-evaluation Distracting injuries Altered mental status Age < 18 years old Pregnant patients Paraplegia Uncommon – high velocity injuries ie MVC and falls
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Distal femur fracture Anatomy: Vascular
close to femoral & popliteal vessels Uncommon – high velocity injuries ie MVC and falls
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Distal femur fracture Anatomy: Neuro Tibial nerve
gastrocnemius, plantaris Peroneal/Deep Peroneal nerves Supplies anterior compartment (dorsiflexion) Sensory to first dorsal interosseus cleft Uncommon – high velocity injuries ie MVC and falls
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Distal femur fracture Complications of these fractures are the same as for femoral shaft fracture: DVT/PE, fat embolism, delayed/non/malunion, adhesions, angulation deformity and OA ****growth disturbances in kids (up to 65%)
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Distal femur fracture Supracondylar Intracondylar Condylar
Extra-articular No hemarthrosis Intracondylar Intra-articular Condylar Location of fracture determines if there will be a hemearthrosis.
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Name this fracture Tib plat
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Tibial Plateau Fractures
Anatomy Vascular High incidence of popliteal A damage Neuro Perineal N damage Ligaments 25% have associated ligamentous injury
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Tibial Plateau Fractures
Plateau slopes 10 degrees from A P May not appear to be at same level Lateral plateau slightly convex upward Medial plateau slightly concave upwards
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Schatzker Classification
MC MOI is axial loading with valgus force Types I-III are all lateral plateau fractures. These may be managed by primary care pnysician
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Schatzker Classification
Type IV (15%): Medial plateau Type V: Bicondylar Types I-III are all lateral plateau fractures. These may be managed by primary care pnysician
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Schatzker Classification
Type VI: Bicondylar and tibial shaft Types I-III are all lateral plateau fractures. These may be managed by primary care pnysician
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Tibial Plateau Fractures
Occult fracture: Lateral may show lipohemarthrosis Same mechanism as ACL injury: hyperextension, rotation, add/abd Suspect when +lachmann with inability to weight bear All need to see ortho – 1-2 immob 4-6wks, 3 - ORIF
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Name this fracture Tib plat
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Segond Segond fracture:
Avulsion of lateral plateau at site of insertion of lateral capsular lig Marker for ACL disruption and anterolateral rotary instability Xray – lateral capsule sign
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Name this fracture Types I-III are all lateral plateau fractures. These may be managed by primary care pnysician
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Tibial Spine Fractures
Type I Incomplete avulsion with no displacement Type II incomplete avulsion with displacement Type III Completely avulsed fragment Same mechanism as ACL injury: hyperextension, rotation, add/abd Suspect when +lachmann with inability to weight bear All need to see ortho – 1-2 immob 4-6wks, 3 - ORIF
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Tibial Spine Fractures
Don’t forget the TUNNEL views
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Name this fracture
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Tibial Tuberosity Fractures
Type I Distal fragment displaced proximally and anteriorly Type II Fragments hinged at proximal portion Large fragment extending into physis These are seen typically in adolescent boys. Mech is forced flexn with quads contraction. Ossification centre at this location is usually closing. Type 1 – immobilize Type 2 – closed reduction and immobilize – ortho to follow Type 3 – ORIF immob
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Tibial Tuberosity Fractures
Type III Extension into articular surface Forced flexion with contracted quads Uncommon after growth plates fuse/close
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Name this fracture? Forced flexion with contracted quads
Uncommon after growth plates fuse/close
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Patellar Fracture Classification:
Transverse, vertical, stellate/comminuted, marginal, osteochondral avulsion Proximal or distal pole Displaced or nondisplaced Undisplaced = <3mm, no step deformity, ext mech intact
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Patellar Fracture Radiology: AP Lateral Sunrise
Tangential view across 45 degree flexed knee Shows small vertical fractures of patella
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Patellar Fracture What about this?
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Patellar Fracture Sharp, nonsclerotic margins = acute fracture
Smoother, sclerotic margins = non acute
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Patellar tendon rupture
What about this pt? sudden onset of pain when playing football.
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Patellar tendon rupture
Radiology: Patella alta Ratio of patellar tendon length to patella >1:2 is abnormal Poorly defined soft tissue mass Retracted tendon +/- soft tissue calcific densities Avulsed bone fragments Patellar tendon length: inferior pole of tendon to superior margin of tibial tubercle/tuberosity
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Practise Intercondlar fracture
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Practise Type 1 tib plateau – lateral split. No compression. CT and other views would further delineate typ1- vs typ2
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Practise Tibial spine – 2-3
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Practise Condylar fracture and likely patellar
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Practise Displaced transverse patellar fracture
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Practise Segond
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Practise Type 2 tib plateau – lat plateau plus depression
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Practise Supra condylar, comminuted
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Practise Type 5 tib plateau. No comminution of tib shaft
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Practise Intercondylar femur fracture
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Practise Nondisplaced transverse patella fracture
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Practise Type 2 tibial tubercle fracture – immobilize ortho to follow
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Practise Tib plateau type 5
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Practise Comminuted patellar fracture
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Practise Tibial tubercle type 3. Will require ortho – ORIF, also note the patella is quite high
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Practise Type 2 tibial plateau
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Practise Inf pole patellar fracture, minimally displaced
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Practise Tibial spine – note unclear cortex along spines
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Practise Tib plateau type 6
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Practise Patellar tendon rupture
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Practise supracondylar
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Practise Type 3 tibial plateau
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Type 3 tibial plateau
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Sub troch plus femoral shaft
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Ankle Fractures Anatomy Ankle Rules Classification Practice
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BONES Fibula Tibia Talus
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LIGAMENTS Syndesmotic Ligaments Medial Collateral Ligaments Lateral
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Ankle Fractures Ring structure Disruption of >1 part = unstable
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Ottawa Ankle Rules Sensitivity ~100% Specificity ~40% Age 55 or older
Inability to weight bear both immediately and in ER (4 steps) Bony tenderness over posterior distal 6 cm of lateral or medial malleoli Sensitivity ~100% Specificity ~40% Don’t use on subacute or chronic injuries, unreliable with EtOH Being validated in kids
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Xray views AP Fractures of: Malleoli Distal tibia/fibula Plafond
Talar dome, body and lateral process Calcaneous
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Xray views
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Xray views If TF clear space or overlap are greater than those values then consider syndesmotic injury
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Xray views Mortise Ankle 15-25 degrees internal rotation
Evaluates articular surface between talar dome and mortise Types I-III are all lateral plateau fractures. These may be managed by primary care pnysician
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Mortise view
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Mortise view Medial clear space Tibfib clear space
Between lateral border of medial malleous and medial talus <4mm is normal >4mm suggests lateral shift of talus Tibfib clear space <5mm Talar subluxation or deltoid lig rupture
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Mortise views Talar tilt Normal = -1.5 to +1.5 degrees (ie. Parallel)
Can go up to 5 degrees in stress views <2mm difference between medial and lateral talar/plafond distances
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Xray views Lateral Fractures of: Talar neck Displacement/
anterior/posterior tibial margins Talar neck Displacement/ dislocation of talus Types I-III are all lateral plateau fractures. These may be managed by primary care pnysician
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Weber Classification Weber A= below tibiotalar joint A1: A2: A3:
No disruption of syndesmosis A1: Lat maleolus only A2: Lat maleolus plus deltoid tenderness/medial mal # A3: Lat maleolus plus posterior mal # Used to classify fractures with lat maleolus Used to classify risk of syndesmosis injury and subsequent need for ortho repair A is usually stable B often has ligamentous injury. If mortise is wide, likely unstable
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Weber Classification Weber B = at level of tibiotalar joint
Partial disruption of syndesmosis Used to classify fractures with lat maleolus Used to classify risk of syndesmosis injury and subsequent need for ortho repair A is usually stable B often has ligamentous injury. If mortise is wide, likely unstable
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Weber Classification Weber C= above tibiotalar joint
Disrupts syndesmosis Unstable A is usually stable
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Pott’s Classification
Unimaleolar Bimaleolar Trimaleolar
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Pott’s Classification
Unimaleolar Lat maleolus: use Weber classification Medial maleolus: rarely in isolation Watch for Maisonneuve Post maleolus: rarely in isolation
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Pott’s Classification
Bimaleolar Unstable Often have associated syndesmosis injury Trimaleolar
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Name this fracture
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Maisonneuve Medial maleolar fracture/lig disruption plus proximal fibular fracture Syndesmosis injury
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Name this fracture
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Pilon Fracture of distal tibial metaphysis High energy mechanism
Association with other injuries Calcaneous, tib plateau, fem neck, pelvis, spine, abdo Multiple complication and poor outcomes High energy mechanism. Pattern depends on position during impact
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Examples… Maisonneuve
This is an AP. See asym joint (mortise would be better for commenting on medial clear space.). Increased TF clear space, decrease tf overlap
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Examples… Weber C
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Examples… Trimaleolar Mortise view: widened medial clear space
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Examples… Bimaleolar Weber A2
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Examples… Ligamentous injury. Abnormalities: abnormal talar tilt and widening of joint space
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Examples… Weber C Describe the abnormalities seen on mortiseview: loss of overlap of tib/fib, increased clear space
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Examples… trimaleolar
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Examples… Pilon
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Examples… Weber A, lateral maleolus
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Examples… Bimaleolar – lateral and posterior maleoli
AP- Middle – less than 10mm overlap, talar subluxation Moriseview L: widened medial clear space, talar tilt likely greater than 2mm difference
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Examples… Fracture dislocation Trimaleolar
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Examples… What if this patient was tender over the deltoid ligament?
Weber A(2) Functional bimaleolar fracture. What if this patient was tender over the deltoid ligament?
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Examples… Weber C Abnormalities:
AP: tf clear space hard to measure here. Overlap looks ok Mortise: assym joint space. Increased TF clear space
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Examples… Bimaleolar ?trimaleolar Midened clear space, talar tilt,
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Examples… Pilon What are associated injuries? Spine, pelvis, intraabdominal
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Sub troch plus femoral shaft
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Sub troch plus femoral shaft
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Sub troch plus femoral shaft
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Sub troch plus femoral shaft
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High Ankle Sprain Also known as a syndesmosis ankle sprain
May include injury to : distal anterior inferior tibiofibular ligament (AITFL) Posterior inferior tibiofibular ligament (PITFL) Distal interosseous ligament (IOL) Prolonged recovery
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High Ankle Sprain Exam: Pain over syndesmosis
Pain with external rotation Squeeze test
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High Ankle Sprain Radiology: Ankle views if significantly tender
Stress views not recommended acutely No change in management
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High Ankle Sprain Type 1-2 Type 3 (rupture) PRICE therapy
Early ambulation Physio/Sports med to follow Type 3 (rupture) Ortho to see ORIF
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Name this abnormality Lisfranc
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Approach to Radiographs
Lisfranc - approach Approach to Radiographs Fracture: 2nd metatarsal base: evaluate for fracture, avulsions and displacement *** fracture of proximal 2nd MT is indicative of a Lisfranc injury The second metatarsal has strong connections to the cuneiforms and it is difficult for the 2nd metatarsal to dislocate without sustaining a fracture through it’s base Thanks Marc
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Approach to Radiographs
Lisfranc - approach 2. Straight lines: On AP and Oblique films medial aspect of the 2nd MT base and the middle cuneiform Thanks Marc
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Approach to Radiographs
Lisfranc - approach Approach to Radiographs 2. Straight lines: Medial border of the 4th MT base and the cuboid Lateral border of the base of 3rd MT with lateral border of the 3rd cuneiform Thanks Marc
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Approach to Radiographs
Lisfranc - approach Approach to Radiographs 3. “fleck sign” Small avulsed fragments indicate ligamentous injury and joint disruption Thanks Marc
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Approach to Radiographs
Lisfranc – approach Approach to Radiographs 4. “Step-off” On lateral films No metatarsal shaft should be more dorsal than it’s respective tarsal bone Thanks Marc
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Approach to Radiographs
Lisfranc - approach Approach to Radiographs 5. Separation: base of the 1st and 2nd MT 1st and 2nd cuneiforms ***strongly suggestive of a subluxation 6. Fracture: Cuboid Cuneiforms Navicular MT shafts ***suggestive of Lisfranc Thanks Marc
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2 types of Lisfranc injuries
Lisfranc - Classification 2 types of Lisfranc injuries Homolateral type: Lateral displacement of the 1st through 5th MT heads Divergent type: The 1st (and occasionally the 2nd) MT dislocates medially or stays fixed, while the more lateral metatarsals are displaced laterally Thanks Marc
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Practice Widening of curneiforms (1-2) and fracture 2nd MT makes Lisfranc likely
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Practice Widening MT1 and MT2. MT2 doesn’t line up with cuneiform
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A little bit of extra info….
Xray presentation with calcaneus, talus, navicular fractures Label this diagram
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Anatomy Label this diagram
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Anatomy Label this diagram
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Case 35M working on roof, falls, lands like a cat
c/o bilat heel pain and back pain
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Case
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Case
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Calcaneus Fracture Calcvaneus is most commonly fractured tarsal
Multiple joint surfaces – therefore easy to have intraarticular fractures- talus and cuboids Make sure you look at the calcaneous from posterior view – may help with dx. (may look short, wide, or tilted) Pt won’t be able to wt bear – unless it is during stampede
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Calcaneus fractures Posterior tuberosity apex of anterior process
Bohler’s angle – degrees is normal Measured on Lateral film Posterior tuberosity apex of anterior process apex of posterior facet
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Calcaneus Fracture Mechanism: Intra or extraarticular Associations:
High energy axial load Intra or extraarticular Associations: 7% bilateral 10% spine compression # 25% other LE injury Calcvaneus is most commonly fractured tarsal Multiple joint surfaces – therefore easy to have intraarticular fractures- talus and cuboids Make sure you look at the calcaneous from posterior view – may help with dx. (may look short, wide, or tilted) Pt won’t be able to wt bear – unless it is during stampede
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Calcaneus Fracture Imaging: Important distinctions:
Standard AP/Lat foot and ankle views Axial +/- CT Important distinctions: Involvement of subtalar joint Depression of posterior facet The above often require ortho intervention Easily can be underestimated with xray therefore many/most get CT for better visualization of fracture
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Calcaneus Fracture Ortho: Outcomes: Treatment patterns vary
Intraarticular and comminuted fractures must be seen Outcomes: Poor outcomes >50% have loss of ROM, chronic pain, and functional disability Calcvaneus is most commonly fractured tarsal Multiple joint surfaces – therefore easy to have intraarticular fractures- talus and cuboids Make sure you look at the calcaneous from posterior view – may help with dx. (may look short, wide, or tilted) Pt won’t be able to wt bear – unless it is during stampede
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Case 32M fell and landed with pointed toes
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Case
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Talar fractures Anatomy: 7 articular surfaces (60% of surface)
Regions: Body Neck Head
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Talar fractures Minor talar fractures:
HEAD AND NECK: Avulsion and chip fractures of superior surface BODY: Lateral, medial, posterior body AND osteochondral of talar dome Require immobilization and referral to ortho for f/u Calcvaneus is most commonly fractured tarsal Multiple joint surfaces – therefore easy to have intraarticular fractures- talus and cuboids Make sure you look at the calcaneous from posterior view – may help with dx. (may look short, wide, or tilted) Pt won’t be able to wt bear – unless it is during stampede
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Talar fractures Talar neck fractures 50% of major talar injuries.
Mechanism: extreme dorsiflexion Hawkins classification Often associated fractures Calcvaneus is most commonly fractured tarsal Multiple joint surfaces – therefore easy to have intraarticular fractures- talus and cuboids Make sure you look at the calcaneous from posterior view – may help with dx. (may look short, wide, or tilted) Pt won’t be able to wt bear – unless it is during stampede
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Fracture type influences management & prognosis
Talar fractures Calcvaneus is most commonly fractured tarsal Multiple joint surfaces – therefore easy to have intraarticular fractures- talus and cuboids Make sure you look at the calcaneous from posterior view – may help with dx. (may look short, wide, or tilted) Pt won’t be able to wt bear – unless it is during stampede Type 1: nondisplaced Type 2: subtalar subluxation Type 3: dislocation of the talar body (50% open #’s) Type 4: dislocation of the talar body & distraction of the talonavicular joint. Fracture type influences management & prognosis
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Talar fractures Talar body fractures 23% of all talar fractures
Ie posterior or lateral process fracture Major talar body fractures are uncommon usually axial loading Reduction of talar fractures – hold forefoot and hindfoot and apply longitudinal traction in plantarflexion
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Talar fractures Talar head fractures Uncommon (5-10%)
Compression transmitted through the talonavicular joint applied on a plantarflexed foot Reduction of talar fractures – hold forefoot and hindfoot and apply longitudinal traction in plantarflexion
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Talar fractures Management: Outcomes:
Major fractures require ortho consult Outcomes: Risk of AVN, OA, and chronic pain Reduction of talar fractures – hold forefoot and hindfoot and apply longitudinal traction in plantarflexion
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Case 18F playing soccer, tripped and twisted foot
Not sure of how she twisted/landed
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Case
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Navicular Fracture Classification: Dorsal avulsion Tuberosity Fracture
>50% of navicular #s Eversion injury Associated with deltoid ligament injury Minimal articular involvement Tuberosity Fracture Eversion injury Associated with posterior tibialis tendon avulsion Avulsion fractures usually associated with ligamentous injuries. Ie insertion of deltoid ligament Tuberosity # usually occur at site of post tibialis tendon insertion
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Navicular Fracture Classification: Body Fracture Rare Axial loading
Comminuted, intraarticular Avulsion fractures usually associated with ligamentous injuries. Ie insertion of deltoid ligament Tuberosity # usually occur at site of post tibialis tendon insertion
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Navicular Fracture Clinical Imaging Pain on palpation
+/- pain on passive eversion or active inversion Imaging Standard foot views +/- bone scan Calcvaneus is most commonly fractured tarsal Multiple joint surfaces – therefore easy to have intraarticular fractures- talus and cuboids Make sure you look at the calcaneous from posterior view – may help with dx. (may look short, wide, or tilted) Pt won’t be able to wt bear – unless it is during stampede
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Navicular Fracture Why do we care? Management: Significant risk of AVN
Outpatient Ortho: Dorsal avulsion and tuberosity # with minimal articular involvement Immobilize 4-6 wks ED Ortho consult Body#, displaced #, >20% of articular surface involved Calcvaneus is most commonly fractured tarsal Multiple joint surfaces – therefore easy to have intraarticular fractures- talus and cuboids Make sure you look at the calcaneous from posterior view – may help with dx. (may look short, wide, or tilted) Pt won’t be able to wt bear – unless it is during stampede
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Practice…. Calcaneus fracture
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Practice… Talus avulsion fracture
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Practice…
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Practice…. Calcaneus fracture
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Practice…. Dorsal avulsion navicular
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Practice…. Calcaneus fracture
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Practice…. Dorsal avulsion navicular
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Practice…. Calcaneus fracture
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Practice…. Osteochondritis dissecans
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Practice…. talar fracture – posterior process
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Practice…. Navicular body fracture
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Practice…. Calcaneus fracture
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Practice…. Navicular, cuneiform, first MT fractures
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