MSK Flashcards

Question

Define Alkaline Phosphate

Answer 1

Often elevated with bone turnover. Not specific or sensitive.

Answer 2

Elevated with inflammation or infection.

Answer 3

Not yet standardized. Markers of bone breakdown: breakdown products of type I collagen, pyridinoline. Markers of bone formation: osteocalcin, bone-specific alkaline phosphatase, type I procollagen.

Answer 4

Imaging Arthrocentesis w/ synovial fluid analysis +/- labs if needed

Answer 5

Hemarthrosis without trauma - PT/INR, PTT, CBC Evidence of joint inflammation without infection or crystals - ESR/CRP, CBC, CMP Testing for systemic rheumatic disease IF suspicion for that disease Testing for Lyme disease if suspicion is high Synovial biopsy - rare Fungal infections Sarcoidosis

Answer 6

CBC, CMP, urinalysis Arthrocentesis with synovial fluid analysis Labs based on clinical suspicion Imaging – rarely needed Synovial biopsy - rare

Answer 7

ESR/CRP, Viral antibodies (Hepatitis B, Hepatitis C, Parvovirus B19) Suspected systemic illness: RA, Lupus, and other systemic diseases. Viral antibodies; Hepatitis B, Hepatitis C, Parvovirus B19

Answer 8

CMP, TSH / PTH, Imaging (x-ray), Screening for depression.

Answer 9

Local anesthetic given. Fluid collected from the joint space with sterile technique.

Answer 10

Joint effusion/pain for diagnosis of underlying pathology (Infection, Arthritis, Crystalline arthritis, Synovitis, Neoplasm) Therapeutic: Injection of anti-inflammatory medications into the joint.

Answer 11

Artificial joint and replacement joint. Lesions of skin overlying the injection site.

Answer 12

Gout and CPPD.

Answer 13

Clear, sometimes straw colored.

Answer 14

Differential can be important too.

Answer 15

Negative birefringent yellow crystals. Positive birefringent blue crystals.

Answer 16

Cytology. Gram stain and culture.

Answer 17

Gout and CPPD

Answer 18

Hyperuricemia: Increased production, Decreased excretion, Increased purine intake

Answer 19

> 40 years old

Answer 20

Male > Female

Answer 21

Sudden onset, Monoarticular (Small joints), Severe pain, Swelling, erythema, warmth, +/- tophi

Answer 22

Also known as Pseudogout. PX Unknown

Answer 23

More likely with age

Answer 24

Acute, subacute, or chronic, Monoarticular or Polyarticular, Mild to moderate pain, Mimics other types of arthritis, Think of this with recurrent, +/- chondrocalcinosis

Answer 25

Clinical criteria: Podagra-great toe involvement Arthrocentesis: Monosodium urate crystals, Yellow-negative birefringent, Needle shaped, Serum uric acid level (not diagnostic, can be low/normal during acute attack)

Answer 26

Clinical criteria: older patients with recurrent inflammatory arthritis Arthrocentesis: calcium pyrophosphate dihydrate crystals, Blue-positively birefringent, Rhomboid-shaped

Answer 27

Septic arthritis

Answer 28

Firm yellow or white papules or nodules

Answer 29

Increased production, Decreased excretion (CKD, Ethanol, Diuretics), Increased purine intake (Organ meats, Seafood, Beer)

Answer 30

CPPD or Pseudogout

Answer 31

Rheumatoid factor (RF), Anti cyclic citrullinated peptide (Anti-CCP), Erythrocyte Sedimentation Rate (ESR), C Reactive Protein (CRP)

Answer 32

Bony erosions, Deformities

Answer 33

Patients with clinical symptoms consistent with RA, Not a screening test ## Footnote Not a screening test

Answer 34

IgM antibodies made against IgG antibodies. Present in ~70% of patients with RA, Associated with RA but not specific, Can be elevated in other systemic rheumatic disorders, granulomatous disease, chronic infections, and cancers

Answer 35

More specific to RA Patients with clinical symptoms consistent with RA Patients with undifferentiated arthritis Prognostic markers in patients diagnosed with RA

Answer 36

Autoantibodies against citrullinated proteins Citrullination is a post-translational modification of arginine to citrulline More specific than RF

Answer 37

RF-can be mildly elevated +/- anti-CCP-rarely elevated

Answer 38

“Pencil in a cup” Psoriatic arthritis

Answer 39

Expected findings: Negative RF and anti-CCP Elevated WBCs and platelets Elevated ESR and CRP Very elevated ferritin

Answer 40

Polyarticular. Must have psoriasis to get this. Etiology: Unknown Occurs in about 20% of patients with psoriasis Prevalence increased in patients with: HIV Human Leukocyte Antigen B27 (HLA-B27)

Answer 41

Labs: HLA-B27 (not always present, but if positive increases likelihood). Imaging: Looking for sacroiliitis.

Answer 42

ANA, Anti-dsDNA, Anti-Smith, Anti-chromatin, Anti-phospholipid, Anti-Ro/SSA, Anti-La/SSB, Anti-RNP, Anti-histone.

Answer 43

Initial test if suspect SLE. Often ordered as part of workup for proteinuria in AKI or CKD.

Answer 44

Group of autoantibodies against nucleic acids and nucleoproteins within the nucleus of cells. Many different subtypes.

Answer 45

Titer (dilutional concentration). Initial test is usually a specific dilution (1:40-negative). If positive, serial dilution is done until no longer positive. The highest dilution that is still positive is what is reported. The higher the number more active the disease (1:80, 1:160, 1:320, etc). The test is performed with indirect immunofluorescence. Pattern may help differentiate disease processes.

Answer 46

Negative ANA helps rule out SLE (high sensitivity). Positive ANA does not diagnose SLE (low specificity). Can be positive in people without an autoimmune disorder (~5%). Once positive, usually remains positive.

Answer 47

Positive ANA Diagnosis for SLE Monitoring SLE activity

Answer 48

High titers associated with SLE Low titers can be found in other diseases and with certain drugs Levels change with disease activity Higher during flare Can trend down to normal when well-controlled

Answer 49

If ANA is negative, there is no reason to order further SLE labs. If ANA is positive, additional testing should be performed. Anti-dsDNA, Anti-Smith, Anti-RNP, Anti-Ro/SSA, Anti-La/SSB, Anti-chromatin, Anti-histone. With Anti-Smith, Anti-RNP, Anti-Ro/SSA and, Anti-La/SSB as extractable nuclear antigen antibodies.

Answer 50

Positive ANA Diagnosis of SLE

Answer 51

High specificity for SLE. Low sensitivity though. Titers remain positive after disease activity has subsided Useful for pts who may have near normal anti-dsDNA No evidence to suggest useful in monitoring disease activity or progression

Answer 52

All SLE patients should be screened for: - Anti-cardiolipin Ab - Anti-β 2 glycoprotein - Lupus anticoagulant

Answer 53

Indications for anti-chromatin include: - Positive ANA - Concern for SLE - Especially drug-induced

Answer 54

Anti-chromatin is found in the majority of SLE patients and nearly 100% of drug-induced SLE. Levels have a direct correlation with renal damage from lupus.

Answer 55

Autoantibodies, such as anti-chromatin, form immune complexes that are deposited in the glomerulus.

Answer 56

Positive ANA Concern for Sjögren’s syndrome

Answer 57

Autoantibodies that recognize one of two cellular proteins Primarily found in Sjögren’s syndrome Can be positive in ANA-negative SLE

Answer 58

Positive ANA Concern for Sjögren’s syndrome

Answer 59

Autoantibodies that target a protein in the nucleus that goes back and forth between the cytoplasm and nucleus Usually positive in Sjögren’s syndrome High sensitivity and specificity Negative in SLE

Answer 60

ANA + Anti-Scl 70 Ab + Anti-U3 RNP Ab + Anti-RNA polymerase Ab + Correlates with disease severity Not going to have the classic skin findings but will tend to have a mix of all 3 antibodies

Answer 61

ANA + Anti-centromere Ab +

Answer 62

Anti-Jo Ab-positive (high specificity, moderate sensitivity) CPK-elevated Aldolase-alternative to CPK and often tested when CPK is normal ANA-may be positive Would require additional testing to rule out other etiologies ESR and CRP-usually NOT elevated

Answer 63

Anti-Jo Ab-positive CPK-elevated: Aldolase-alternative to CPK and often tested when CPK is normal ANA-may be positive but not diagnostic: Would require additional testing to rule out other etiologies ESR and usually NOT elevated Skin findings are a big differentiation from polymyositis

Answer 64

ESR- elevated CRP-elevated ANA is negative CPK is normal

Answer 65

Motor neuron cell bodies (spinal cord and brainstem) → axon → axon terminal

Answer 66

Aka the neuromuscular junction. Region of the muscle fiber plasma membrane that lies directly under the terminal portion of the axon. Acetylcholine (ACh). At the end of the motor neuron, we have a small vesicles right in those vesicles of the motor neuron contain neurotransmitter Ach. You can see that once we have the release of acetylcholine into binding on the circle, and we have propagation of the action potential into the into the muscle to cause contraction.

Answer 67

1. Motor neuron receives stimulation of action potential that moves down the axon and reaches the axon terminal 2. Action potential stimulates the opening of voltage gated Ca2+ channels allowing Ca to flow into the neuron 3. Ca2+ entry causes the release of ACh vesicles into the synaptic cleft 4. ACh binds to nicotinic receptors on motor end plate of muscle causing the opening of Na and K ion channels 5. The entrance of Na+ into the muscle cell (and K outward) causing depolarization and generation of an action potential in the muscle fiber which is propagated through the sarcolemma, T-tubules, and sarcoplasmic reticulum* (6-8) 9. ACh is degraded by acetylcholinesterase to prevent

Answer 68

The motor neuron itself receives an action potential moves it downward to the terminal (or the button) portion of the neuron, and from that we have calcium channels open and calcium flows into the neuron cell. Calcium stimulates the release of the binding of these vesicles here to release into the synapse. Then it will go to the sarcoplasmic membrane and bind to receptors specifically nicotinic receptors on this causes of sodium and potassium ion channels. The generation of depolarization in the muscle fiber spread to the sarcoplasmic reticulum. Calcium is being released by reticulum and causes contraction.

Answer 69

Acetylcholine is broken down by Acetylcholinesterase, because the more Ach that gets bound is the more muscle contraction we have. We don’t always want to be contracting out muscle because that could be problematic. so you know it and receptors are actually really good targets for drugs such as suing rocky vecuronium. These are called neuromuscular blocking agents so paralytics. For example when we paralyze people because we don’t have to use as much anesthetic.

Answer 70

People still move when they’re unconscious for example, and when people are placed on ventilators, we need to paralyze them to control their their breathing

Answer 71

Good targets for rocuronium, succinylcholine, vecoronium. These are called neuromuscular blocking agents (paralytics). For example when we paralyze people because we don’t have to use as much anesthetic.

Answer 72

Botulisim. Botulism causes paralysis causes tetany and is a type of food poisoning. It prevents the release of acetylcholine on the vesicles within the neuron so that prevent the release of Ach and therefore cause paralysis. Botox has this same mechanism.

Answer 73

Sarcolemma (plasma membrane) → transverse (T) tubules → sarcoplasmic recticulum (Ca 2+) → Ca2+ binds to troponin to activate the sliding filament mechanism to pull the tropomyosin to allow for cross bridgine of actin and myosin.

Answer 74

calcium ATPase will pump calcium back into the sarcoplasmic reticulum by active transport, so where we have the reverse process to get rid of all calcium from binding and so that calcium can be recycled back into the reticulum

Answer 75

When we are considering the mechanics of muscle contraction, we should think about the tension generated and the load. Isometric contraction occurs when a muscle develops tension but does not shorten or lengthen, like when carrying a bag, meaning supporting a load in a CONSTANT position. Muscle is contracting but NOT shortening Isotonic contraction occurs when a muscle changes lengthen while the load on the muscle remains constant so like in weight training.

Answer 76

Concentric contraction- muscles curling up and contracting and shortening Eccentric contraction- muscle lengthens but is still generating force so when we are lowering the weight back down

Answer 77

Muscle exerted by an object

Answer 78

Our contraction vs what we are contracting against

Answer 79

The force that is exerted on a muscle

Answer 80

Location Type Comminution Displacement Translation Angulation Rotation Shortening Articulation Mechanism

Answer 81

Comminuted fracture due to gunshot injury Has to have more than 2 pieces to be considered comminuted Shattered tib/fib

Answer 82

Olecranon fracture - comminuted

Answer 83

Comminuted humeral shaft fracture

Answer 84

Comminuted humeral shaft fracture

Answer 85

2 bone fragments in the fracture

Answer 86

Comminuted interochanteric fracture

Answer 87

Often missed

Answer 88

Cervical fracture dislocation at C5-C6

Answer 89

Thoracic spine fracture-dislocation Towards the lower thoracic and lumbar spine

Answer 90

Rotation, angulation, translation, impaction, distraction

Answer 91

Fracture displacement and impaction leads to limb shortening

Answer 92

Spiral fracture of the femur

Answer 93

Spiral fractures of the right distal tibia and fibula

Answer 94

Transverse fracture of the 5th metacarpal neck Most common type of metacarpal fracture and occurs due to impact fracture or direct blow with closed fist.

Answer 95

Useful for evaluating bony abnormality as source congenital cervical rib bony abnormality of 1st rib or clavicle (congenital anomaly, malunited fracture, callus, Paget disease, tumor) elongated C7 transverse process

Answer 96

Elongated C7 transverse process

Answer 97

Salter-Harris Classification: Centers around location of fracture in relation to growth plate Torus (aka buckle fracture)

Answer 98

Salter-Harris Type 1 fracture Separation of the epiphysis from the diaphysis

Answer 99

Salter-Harris Type 2 fracture Through the diaphysis and through the growth plate

Answer 100

CT of Salter-Harris Type 3 fracture Through the growth plate and through the epiphysis

Answer 101

Salter-Harris Type 4 fracture Through the diaphysis, growth plate, and epiphysis

Answer 102

These are difficult to see on radiographic studies. Typically identified once growth arrest noted.

Answer 103

Incomplete radial fracture Torus (aka buckle fracture)

Answer 104

Spondylolysis (fracture of the pars) Spondylolisthesis

Answer 105

Spondylolysis Should be a smooth line

Answer 106

SpondylolisthesisDefine Spondylosis

Answer 107

Osteoarthritis of the spine

Answer 108

Inflammation of the vertebrae

Answer 109

A fracture of defect in the pars interarticularis

Answer 110

Forward slippage of one vertebra over another

Answer 111

Spondylolysis Fracture of the pars articularis

Answer 112

Spondylolithesis Vertebrae has slipped under the one above it Height loss

Answer 113

Cervical spondylosis with osteophyte formation

Answer 114

Varus is medial Valgus is lateral

Answer 115

These terms are sued when referring to the forearm Dorsal is towards the back of the hand Volar is towards the palm of the hand

Answer 116

In the PA view, it is hard to tell, but in the lateral view, we see that this looks like a greenstick fracture with dorsal angulation

Answer 117

Dorsal displacement

Answer 118

A- anterior arch of Atlas (C1) B-posterior arch of Atlas (C1) C-body of Axis (C2) D-inferior articular process E-superior articular process F-facet joint G-spinous process H-intervertebral disc space

Answer 119

Make sure lateral masses of C1 do not overhang those of C2 (2) Make sure no asymmetry of the articular spaces between the lateral masses of C1 and the body of C2 (3) Make sure no asymmetry between lateral masses of C1 and dens

Answer 120

1. Central incisor teeth 2. Odontoid process 3. C1 transverse process 4. Inferior articular facet C1 5. Superior articular facet C2 7. Alanto-axial joint 8. Lateral mass of C1 9. Body of C2 10. Spinous process of C2 11. Lamina of C2 12. Pedicle of C2

Answer 121

C1-C4 should be < ½ the width of the vertebral body C5-C7 should be < the width of the vertebral body

Answer 122

Axial loading injury Ex: diving into a swimming pool and hitting one’s head on the bottom

Answer 123

A C1 burst fracture

Answer 124

Jefferson fracture There is a C1 lateral mass extending outside of C2

Answer 125

Trauma, suspicion of bony injury, concern for dislocation, shoulder pain or restriction of movement

Answer 126

Shows the humeral head superimposing the glenoid of the scapula. Displays the entire clavicle, AC joint, scapula, superior ribs, SC joint and proximal humerus.

Answer 127

Demonstrates the degree and direction of any suspected dislocations.

Answer 128

Bone is completely out of the joint, not aligned at all with the joint.

Answer 129

Bone is displaced but not necessarily out of joint.

Answer 130

Usually direct blow or fall onto the shoulder with adducted arm. Can occur from fall on outstretched arm.

Answer 131

Age: 20-40 year olds. Sex: Male > Female (5:1).

Answer 132

Acromioclavicular joint dissociation - type IV. Super pushed in.

Answer 133

Suspicion of bony injury, Suspicion of dislocation, Elbow pain

Answer 134

Trans-scaphoid perilunate dislocation

Answer 135

Posterior (~85%) and Anterior (~10%) Relatively rare but carries high morbidity

Answer 136

Normally associated with high-speed trauma. Can also see with: Sports injuries, Complication of hip replacement, Congenital dislocation

Answer 137

Anterior (~40%)-hyperextension-usually involves PCL tear, Posterior (~33%)-axial load of flexed knee, Lateral (~20%)-varus or valgus force-usually involves tears of ACL and PCL, Rotary (~5%), Medial (~5%)-varus or valgus force

Answer 138

Lateral patella dislocation with femoral condyle fracture. Usually occurs with a twisting motion

Answer 139

Twisting motion with knee in flexion. Often “self reduce”

Answer 140

Osteoarthritis of the spine

Answer 141

Inflammation of the vertebrae

Answer 142

7 cervical vertebrae, 12 thoracic vertebrae, 5 lumbar vertebrae. C1 is the atlas, C2 is the axis, C3-C7 are additional cervical vertebrae.

Answer 143

AP, lateral, and odontoid views are standard. Need to visualize T1 on lateral view. Can do cross table C-spine series if immobile. Additional views can include oblique, lateral flexion, and extension.

Answer 144

In the young, usually from high energy trauma (e.g., MVC, diving, skiing). In the older population, lower energy impact from a fall from standing.

Answer 145

1. Central incisor teeth 2. Odontoid process 3. C1 transverse process 4. Inferior articular facet C1 5. Superior articular facet C2 7. Alanto-axial joint 8. Lateral mass of C1 9. Body of C2 10. Spinous process of C2 11. Lamina of C2 12. Pedicle of C2

Answer 146

Odontoid fracture Disconnected dark line Will need a follow up with CT or MRI to get more detail

Answer 147

Flexion-Distraction vertebral fracture “Chance” fracture Spinous process if sheared both anterior and posterio

Answer 148

Body Pedicle Lateral mass Lamina Spinous process Facet joints

Answer 149

Normal spinous processes should align on AP view

Answer 150

Bones - Loss of body height - Should get bigger the further you go down the spine Pedicle Spinous process Transverse process

Answer 151

Vertebral body Spinous process Transverse process Pedicle

Answer 152

Examine each: Body, Evaluate body height-should get larger from T12-L5, Pedicle (AP view), Spinous process, Transverse process

Answer 153

Jefferson fracture There is a C1 lateral mass extending outside of C2

Answer 154

Intervertebral disc disease Loss of disc height space

Answer 155

Intervertebral disc disease Loss of disc height space

Answer 156

Same process Alignment – 3rd metatarsal should align with lateral cuneiform Check all bones carefully – look for avulsion fractures on calcaneus and cuboid Check joint spaces Check soft tissues

Answer 157

Same process Alignment Check all bones carefully – look for avulsion fractures on talus and navicular Check joint spaces Check soft tissues

Answer 158

Assess alignment of all bones - 2nd metatarsal should line up with intermediate cuneiform Assess each bone - Have a systematic approach – proximal to distal and medial to lateral works - Places to check closely – metatarsals, especially 5th Assess joint spaces Assess soft tissues

Answer 159

Assess the alignment of the tib/fib Assess each bone Assess the joint space around the talus- should be uniform

Answer 160

Normal wrist alignment

Answer 161

Normal wrist alignment Radius, capitate, and lunate should all line up

Answer 162

Identify Adequate ABCS Alignment: Not just of bones but joints Bones: Trace cortical outlines and evaluate for lesions Cartilage: Evaluate joint spaces Soft tissue: Looking for edema, effusions, etc

Answer 163

Used when it is hard to see detail Occult fractures Osteonecrosis Infection Masses Soft tissue injuries – cartilage, tendons, ligaments, muscles Herniated discs Spinal cord stenosis

Answer 164

1. Clavicle 2. Acromion process 3. Greater tubercule 4. Coracoid process 5. Humeral head 6. Lesser tubercule 7. Glenoid fossa 8. Acromioclavicular joint 9. Scapula 10. Humerus

Answer 165

1. Anatomical neck of the humerus 2**. Greater tubercle** 3. Lesser tubercle 4. Surgical neck of humerus 5. Humeral shaft 6.** Humeral head** 7. Glenoid fossa 8.** Acromion 9. Acromioclavicular joint 10. Coracoid process 11. Clavicle** 12. Superior angle of scapula 13. Medial border of scapula 14. Inferior angle of scapula 15, Lateral border of scapula 16.** Scapula**

Answer 166

Normal shoulder x-ray

Answer 167

Assess alignment of ankle and foot bones, each bone, fibula for oblique fracture, foot bones carefully, joint spaces, and soft tissue.

Answer 168

Look at the tib/fib alignment about 1 cm above talus.

Answer 169

Pelvic rim and obturator foramen should be continuous rings, and sacroiliac joints should be symmetric.

Answer 170

Bones, Cartilage (symphysis pubis < 5mm), Soft tissues

Answer 171

Joint space around talus should be even

Answer 172

Assess alignment of ankle and foot bones, each bone, fibula for oblique fracture, foot bones carefully, joint spaces, and soft tissue

Answer 173

Normal shoulder x-ray

Answer 174

1. Clavicle 2. Acromion process 3. Greater tubercule 4. Coracoid process 5. Humeral head 6. Lesser tubercule 7. Glenoid fossa 8. Acromioclavicular joint 9. Scapula 10. Humerus

Answer 175

****Anatomical neck of the humerus **Greater tubercle Lesser tubercle** Surgical neck of humerus Humeral shaft **Humeral head Glenoid fossa Acromion Acromioclavicular joint Coracoid process Clavicle** Superior angle of scapula Medial border of scapula Inferior angle of scapula Lateral border of scapula

Answer 176

1.Olecranon Fossa 2.Medial Epicondyle 3.Olecranon 4.Lateral Epicondyle 5.Radial Head 6.Radial Tuberosity 7.Ulna 8.Radius 9.Humerus

Answer 177

1.Olecranon Fossa 3.Olecranon 4.Lateral Epicondyle 5.Radial Head 7.Ulna 8.Radius 9.Humerus

Answer 178

Suspicion of bony injury, Suspicion of dislocation, Elbow pain

Answer 179

AP and Lateral

Answer 180

Normal elbow series

Answer 181

Normal elbow series

Answer 182

Normal pediatric forearm series of a 5 year old

Answer 183

Normal hand

Answer 184

Normal hand

Answer 185

Normal hand

Answer 186

1. Styloid process of radius. **2. Radius. 3. Ulna. 4.Styloid process of ulna. 5. Scaphoid. 6. Lunate. 7. Triquetrum. 8. Pisiform. 9. Trapezium. 10. Trapezoid. 11. Capitate. 12. Hamate. 13. Base of second metacarpal. 14. Shaft of third metacarpal. 15. Neck of fifth metacarpal. 16. Head of forth metacarpal. 17.Metacarpophalangeal joint. 18. Proximal phalanx. 19. Middle phalanx. 20. Distal phalanx. 21. Sesamoid bones (flexor pollicis brevis, adductor pollicis)** 22. Distal tuft

Answer 187

1.**metacarpal bone** 2.carpometacarpal joint **3.trapezoid 4.trapezium** 5.scapho-trapezio-trapezoid (STT) joint **6.scaphoid** 7.styloid process of radius 8**.radiocarpal joint 9.lunate 10.radius 11.ulna** 12.distal radioulnar joint **13.styloid process of ulna 14.triquetrum 15.pisiform 16.capitate 17.hamate** 18.hook of the hamate

Answer 188

Suspicion of bony injury, assessment of foreign body (road rash, signs of gravel, metallic pieces, shrapnel).

Answer 189

PA, oblique, and lateral. ## Footnote PA is best for anatomy; lateral is useful in determining any angulation/displacement in fracture evaluation.

Answer 190

Trauma, foreign body evaluation, assessment of joint disease.

Answer 191

PA and oblique. ## Footnote Can get lateral if looking for something specific, such as foreign body location.

Answer 192

Normal scaphoid series

Answer 193

**1.Iliac crest 2.Ilium** 3.Anterior sacral foramina **4.Sacroiliac joint 5.Anterior superior iliac spine 6.Anterior inferior iliac spine 7.Ischial spine 8.Superior pubic ramus 9.Obturator foramen 10.Inferior pubic ramus 11.Ischial tuberosity 12.Symphysis pubis 13.Coccyx 14.Femur 15.Lesser trochanter 16.Greater trochanter 17.Femoral neck 18.Femoral head 19.Acetabulum**

Answer 194

Blunt trauma, Hip pain, Paget’s disease, fall, post-op film

Answer 195

AP Can get additional views depending on need: Lateral hip (suspected hip fracture or dislocation), Inlet view (eval of main pelvic ring), Outlet view (suspected shift of hemipelvis), Oblique (eval of acetabulum), Flamingo view (suspected pubic symphysis instability)

Answer 196

Blunt trauma or fall, hip pain, abnormal gait, inability to weight bear, knee pain

Answer 197

AP Can get additional views depending on need: Lateral (do NOT do if suspect fracture). Can get additional views if needed: Frog leg view (used almost exclusively in pediatric population when suspect slipped capital femoral epiphysis - SCFE)

Answer 198

Femur, Lateral and Medial Condyles, Patella, Tibia, Fibula, Tibial Plateau, Tibial Tuberosity

Answer 199

Trauma, Patella tenderness, Unable to flex knee 90*, Unable to bear weight, Identifying: Osteoarthritis, Osteomyelitis, Joint effusions

Answer 200

AP. Lateral and several other views depending on need

Answer 201

Alignment, Bones, Cartilage, Soft tissues

Answer 202

High energy trauma to flexed knee ## Footnote Think dashboard injury; Fall to knee in elderly.

Answer 203

High velocity-MVC; Low velocity-sports injury.

Answer 204

Ankle trauma; Bony tenderness either malleolus; Inability to bear weight; Non-traumatic ankle pain.

Answer 205

AP-anatomical position; Mortise-AP with foot internally rotated about 10*-assess joint space; Lateral-full profile of talus and calcaneus. MUST BE ABLE TO SEE THE 5TH METATARSAL FOR LATERAL AND MORTISE.

Answer 206

Look at the tib/fib alignment about 1 cm above talus.

Answer 207

Pay attention to top of the talus. Some people have small unfused bones at tip of medial or lateral malleolus – may not be a fracture, but a normal variant. If you find one fracture in the ankle, look for others, because they tend to come together. If there is a medial malleolus fracture, image the knee to look for a proximal fibula fracture.

Answer 208

Joint space around talus should be even.

Answer 209

Assess alignment of ankle and foot bones Assess each bone Check fibula for oblique fracture that only shows up in this view Check foot bones carefully Assess joint spaces Assess soft tissue

Answer 210

Assess the alignment of the tib/fib Assess each bone Assess the joint space around the talus- should be uniform

Answer 211

Ankle x-ray eval with lateral view

Answer 212

Lateral view may show an extra bone just above the calcaneus- normal variant

Answer 213

Foot trauma, bony tenderness at base of 5th metatarsal or navicular bone, inability to bear weight more than 4 steps, non-traumatic foot pain.

Answer 214

Dorsoplantar - metatarsals in natural anatomical position, medial oblique - DP view with foot angled medially 30-40*, most pertinent view for evaluation of tarsal bones, lateral.

Answer 215

Can see the tarsal bones the best

Answer 216

Same process Alignment Check all bones carefully – look for avulsion fractures on talus and navicular Check joint spaces Check soft tissues

Answer 217

A C1 burst fracture

Answer 218

Normal cervical vertebrae with odontoid view smooth borders and all connected

Answer 219

Normal odontoid view of the cervical spine

Answer 220

Odontoid fracture Disconnected dark line Will need a follow up with CT or MRI to get more detail

Answer 221

AP, lateral and odontoid views are standard Need to visualize T1 on lateral view Can do cross table C-spine series if immobile Can get additional views if appropriate Oblique, Lateral flexion and extension

Answer 222

What is the mechanism of an odontoid fracture? In the young, usually from high energy trauma (ex:MVC, diving, skiing). In the older population, lower energy impact from fall from standing

Answer 223

Subluxation of C2 over C3 with B pars interarticularis fracture of C2

Answer 224

Most common is hyperextension with axial loading. Seen in MVCs, diving accidents, and contact sports

Answer 225

C2 fracture/aka hangman’s fracture Displacement

Answer 226

Avulsion fracture of C6 or C7 spinous process

Answer 227

Sudden pull or shearing force exerted by muscles (trapezius or rhomboid) following abrupt flexion during activities like lifting or throwing. Can also be seen with direct trauma.

Answer 228

Clay-shoveler fracture in C6

Answer 229

clay -shoveler fracture in C6

Answer 230

Spondylolisthesis

Answer 231

Forward slippage of one vertebra over another

Answer 232

Based on mechanism of injury: Typically refers to thoracolumbar 4 “types”: Compression, Burst, Flexion-Distraction, Dislocation

Answer 233

Benign forward with downward pressure of spine. Though in individuals with severe osteoporosis, it can occur with something as benign as a sneeze or minor fall.

Answer 234

Neurologic defect: not usually. Levels: all though most common thoracolumbar region. Sex: Female > male. Associated disorders: osteoporosis, renal osteodystrophy, tumors of vertebral body.

Answer 235

a compression fracture type of the vertebra Anterior is smaller than the posterior. May be referred to as a 'wedge' fracture.

Answer 236

compression fracture Narrow and wedged.

Answer 237

Lateral compression pelvic ring fracture and in the ilium as well Not in a straight line

Answer 238

Lateral compression, anterior posterior compression, vertical shear

Answer 239

Most common type. Results in a “wind swept” pelvis.

Answer 240

Results in an “open book” fracture.

Answer 241

Most often high energy axial load injury such as MVC or falls.

Answer 242

burst fracture type vertebrae Often due to bone fragments being driven into the spinal canal.

Answer 243

burst lumbar fracture Squished and shifted out of alignment and may cause disruption of height.

Answer 244

Burst fracture Disc height is off and the alignment is off as well Vertebral bodies no longer line up

Answer 245

A special type of extra-articular fracture that occurs due to a fall or jump from a tall height. Associated with burst fractures of the lumbar spine.

Answer 246

Aka chance or seatbelt fracture. 'Seatbelt' acts as a fulcrum and vertebral body tears horizontally ('flexion' of the anterior & middle columns with distraction of the posterior column). Top of the body is slung forward and back.

Answer 247

Neurologic deficit: +/- Usually associated with visceral injury of abdomen. Levels: Upper lumbar, lower thoracic.

Answer 248

Flexion-Distraction vertebral fracture 'Chance' fracture. Spinous process if sheared both anterior and posterior.

Answer 249

Chance fracture. Flexion and distraction fractures typically with a little bit of angulation.

Answer 250

Atlanto-axial subluxation

Answer 251

Usually trauma (hyperextension or hyperflexion), such as MVC, but can be related to instability of the ligaments in the area from issues like down syndrome (ligamentous laxity) or RA.

Answer 252

Bone is displaced but not necessarily out of joint.

Answer 253

Distal clavicle fracture. The artifact is most likely a bra strap or a piece of the gown.

Answer 254

Distal clavicle fracture

Answer 255

Fall directly on the shoulder and may occur in: MVC, FOOSH, infant as a result of birth trauma

Answer 256

Acromioclavicular joint injury- type III

Answer 257

Usually direct blow or fall onto the shoulder with adducted arm. Can occur from fall on outstretched arm

Answer 258

Age: 20-40 year olds Sex: Male > Female (5:1)

Answer 259

Acromioclavicular joint dissociation- type IV ## Footnote Super pushed in

Answer 260

Acromioclavicular joint dissociation. Sometimes not obvious and images can be taken holding weights

Answer 261

Proximal humerus fracture. Surgical neck has been broken and pushed into each other

Answer 262

Usually fall on outstretched arm

Answer 263

Age: > 65 years old. Most common location is surgical neck

Answer 264

Proximal humerus fracture. Two separate pieces

Answer 265

Radial head fracture

Answer 266

Radial head fracture

Answer 267

Radial head fracture Crack is more obvious on this lateral view

Answer 268

Radial head fracture Should see two areas of disruption

Answer 269

Fall on outstretched hand (FOOSH). Can be very subtle and may require additional views

Answer 270

Radial head fracture

Answer 271

Radial head fracture More common in adult population

Answer 272

Anterior fat pad is usually visible but parallel to the humerus.

Answer 273

Associated with radial head fracture. If seen with no obvious fracture, occult fracture should be suspected.

Answer 274

More often associated with supracondylar fracture, though can be radial head. If seen with no obvious fracture, occult fracture should be suspected

Answer 275

Fat pad separation sign: seen on lateral film and fluid from effusion enters the suprapatellar bursa space.

Answer 276

Aka Nursemaids’ elbow.

Answer 277

Axial traction with an extended elbow.

Answer 278

Children age < 5 years old, most often age 1-3.

Answer 279

radial head subluxation

Answer 280

radial head subluxation

Answer 281

radial head subluxation

Answer 282

Posterior dislocation (most common). FOOSH, Direct blow (rare)

Answer 283

Most often children but can occur in adults

Answer 284

Monteggia fracture-dislocation

Answer 285

Fracture of the ulna with proximal radial dislocation

Answer 286

Children and rare in adults

Answer 287

GRISMUS Galeazzi: Radius fracture (distal), Inferior (Distal) disruption of radioulnar joint; Monteggia: Ulnar fracture, Superior (Proximal) dislocation of radial head GRUesome MURder Galeazzi Radius fractureUlna dislocation Monteggia Ulna fracture Radial head dislocation

Answer 288

Fracture of the distal radius with the distal radioulnar joint disruption

Answer 289

FOOSH ## Footnote Children: peak incidence 9-12 years old; Present in adults: about 7% of forearm fractures

Answer 290

Galeazzi Fracture

Answer 291

Greenstick fracture More commonly in pediatric patients

Answer 292

In the PA view, it is hard to tell, but in the lateral view, we see that this looks like a greenstick fracture with dorsal angulation

Answer 293

< 3% of radius/ulna fracture caused by a fall on the flexed wrist. Young males and elderly females are most likely

Answer 294

Smith fracture

Answer 295

Smith fracture

Answer 296

It typically occurs from a FOOSH (fall on an outstretched hand).

Answer 297

Adolescents and young adults are most likely to experience a scaphoid fracture.

Answer 298

Older populations are more likely to end up with a Colles fracture.

Answer 299

~70-80% of carpal bone fractures are scaphoid fractures.

Answer 300

1. Waist (70-80%) 2. Distal pole 3. Proximal pole

Answer 301

Scaphoid fracture may have pain in the anatomical snuff box.

Answer 302

Scaphoid fracture-distal pole may have pain in the anatomical snuff box.

Answer 303

Scaphoid fracture-distal pole may have pain in the anatomical snuff box.

Answer 304

Scaphoid fracture and may have pain in the anatomical snuff box.

Answer 305

Trans-scaphoid perilunate dislocation

Answer 306

Transverse fracture of the 5th metacarpal neck ## Footnote Most common type of metacarpal fracture.

Answer 307

Occurs due to impact fracture or direct blow with closed fist.

Answer 308

Boxer’s Fracture

Answer 309

Boxer’s Fracture

Answer 310

Boxer’s Fracture

Answer 311

Boxer’s Fracture

Answer 312

Truma (MVC, pedestrian vs vehicle, motorbike collisions), Fall from height, Sports injury, Low-energy fall

Answer 313

Right Pubic rami fractures

Answer 314

pubic rami fracture that is bilateral

Answer 315

Atypical femoral fracture 25% displacement

Answer 316

Subtrochanteric femoral fracture- biphosphate related 25% displacement

Answer 317

Femoral neck fracture

Answer 318

Comminuted interochanteric fracture

Answer 319

Subchanteric femoral fracture

Answer 320

Bilateral femoral mid-shaft femur fracture

Answer 321

Femoral mid-shaft fracture

Answer 322

Lateral patella dislocation with femoral condyle fracture. Usually occurs with a twisting motion.

Answer 323

Femoral head stress fracture in the right femur.

Answer 324

Femoral head stress fracture. The patient has had a right below the knee amputation. There is underlying infection at the amputation site.

Answer 325

Anterior shoulder dislocation. More in front and lower than it should be.

Answer 326

Anterior shoulder dislocation on a 'Y' view. More in front and lower than it should be.

Answer 327

Posterior shoulder dislocation Riding high and separated behind the shoulder Takes a lot of force to shift the humerus abducted with internal rotation

Answer 328

Posterior shoulder dislocation axial view

Answer 329

Anterior (>95%) Posterior (about 2%) Inferior (about 1%)

Answer 330

Younger (20-30) - Male > Female Older (60-80) - Female > Male (3:1)

Answer 331

Trauma w/ subsequent pain and restriction of movement

Answer 332

Indirect force on arm while abducted and externally rotated. Think fall on outstretched arm or hit while arm in throwing position.

Answer 333

Humeral head is forced posteriorly during abduction with internal rotation. Think seizure activity, electrocution, or involuntary muscle contraction. May also be from fall on outstretched arm.

Answer 334

Hyperabduction

Answer 335

Luxatio erecta: “erect dislocation”

Answer 336

Anterior hip dislocation Femur has come out of the cup and is in front of the pelvis

Answer 337

Anterior dislocation of the hip Femur has come out of the cup and is in front of the pelvis

Answer 338

Posterior Dislocated hip prosthesis Riding higher and farther back than it is supposed to be

Answer 339

Posterior Hip joint dislocation Riding higher and farther back than it is supposed to be

Answer 340

Anterior Dislocated knee

Answer 341

Posterior Dislocation of the knee

Answer 342

10-17 years old (Avg 13.5)

Answer 343

8-15 years old (Avg 12)

Answer 344

More common in pediatric population.

Answer 345

African Caribbean > Caucasian

Answer 346

Slipped Capital Femoral Epiphysis (SCFE)

Answer 347

Obesity, Hypothyroid, Hypopituitary, Hypoparathyroidism, Renal osteodystrophy, Radiation/chemo

Answer 348

Supracondylar fracture More common in pediatric population.

Answer 349

Supracondylar fracture More common in pediatric population.

Answer 350

Supracondylar fracture More common in pediatric population.

Answer 351

Posterior dislocation (most common), FOOSH, Direct blow (rare)

Answer 352

Most often children but can occur in adults

Answer 353

Condylar fracture of the femur

Answer 354

Posterior dislocation (most common), FOOSH, Direct blow (rare)

Answer 355

Most often children but can occur in adults

Answer 356

Condylar fracture of the femur

Answer 357

Patellar fracture

Answer 358

Patellar fracture Sunrise view of the patella so it is sitting at the top

Answer 359

Patellar fracture

Answer 360

Lateral dislocation of the patella Usually occurs with a twisting motion

Answer 361

Lateral patella dislocation with femoral condyle fracture Usually occurs with a twisting motion

Answer 362

Twisting motion with knee in flexion. Often 'self reduce'.

Answer 363

Contraction of the quadriceps with flexion of the knee.

Answer 364

Most commonly rupture is at the insertion site of the tendon on the patella or tibial tuberosity when trauma is the mechanism. May be associated with small avulsion fracture. In systemic causes, rupture is usually more mid-tendon.

Answer 365

Chronic microtrauma - aka Jumper’s knee. Prior therapeutic intervention (i.e. steroid injection for Jumper’s knee). Systemic illness: CKD, DM, RA, SLE, etc.

Answer 366

patellar tendon rupture Patella is riding higher than usual with an additional hazy appearance.

Answer 367

Patella is riding higher than usual with an additional hazy appearance.

Answer 368

tibial plateau fracture

Answer 369

tibial plateau fracture

Answer 370

Axial loading injury (i.e. fall from a significant height)

Answer 371

Lateral plateau > medial plateau. Plain x-ray often underestimates severity of fracture and additional imaging is needed prior to repair. Often have associated soft tissue injuries.

Answer 372

knee joint effusion

Answer 373

Pay attention to the top of the talus. Some people have small unfused bones at the tip of the medial or lateral malleolus – may not be a fracture, but a normal variant. If you find one fracture in the ankle, look for others, because they tend to come together. If there is a medial malleolus fracture, image the knee to look for a proximal fibula fracture.

Answer 374

May be isolated but more often associated with fractures of other bones in the ankle.

Answer 375

Medial malleolar fracture

Answer 376

Bimalleolar ankle fracture

Answer 377

Trimalleolar fracture This is why it is important to get multiple views.

Answer 378

Often from lateral blow/force. In conjunction with ankle fracture is known as a Maisonneuve fracture.

Answer 379

Fracture of proximal fibula with unstable ankle injury (widening of the ankle mortise on x-ray).

Answer 380

Pronation with external rotation.

Answer 381

Maisonneuve Fracture. Fracture of proximal fibula with unstable ankle injury (widening of the ankle mortise on x-ray).

Answer 382

A fracture of the calcaneus that occurs outside of the joint space. ## Footnote Represents 25-30% of calcaneal fractures.

Answer 383

Extra-articular calcaneal fracture

Answer 384

A fracture of the body of the calcaneus within the joint. Represents 70-75% of calcaneal fractures.

Answer 385

A special type of extra-articular fracture that occurs due to a fall or jump from a tall height. Associated with burst fractures of the lumbar spine.

Answer 386

An extra bone just above the calcaneus may be visible on a lateral view. This is considered a normal variant.

Answer 387

1. AP - anatomical position 2. Mortise - AP with foot internally rotated about 10° to assess joint space 3. Lateral - full profile of talus and calcaneus Must be able to see the 5th metatarsal for lateral and mortise views.

Answer 388

Jones Fracture

Answer 389

Transverse fracture at base of the 5th metatarsal and affects the 4th and 5th metatarsal articulation.

Answer 390

Significant adduction force to forefoot with ankle plantar flex (i.e. planted forefoot turning out). Concern is blood flow and repair as high incidence of poor healing.

Answer 391

Disruption of the Lisfranc joint (tarso-metatarsal). Several types and mechanism depends on type.

Answer 392

Crush injury. Forefoot abduction with planted hindfoot. Foot stuck in stirrup. Cleated foot planted in turf. Forced plantar flexion with axial force. Will likely require additional imaging.

Answer 393

Lisfranc Injury

Answer 394

Osteophytes Smooth lines around the osteophyte differentiates it from a fracture piece

Answer 395

Aka bone spur Extra growth of bone tissue near other bones Typically benign but can cause pain depending on location

Answer 396

Hook-like osteophytes

Answer 397

Cervical spondylosis with osteophyte formation

Answer 398

Non-marginal osteophyte

Answer 399

Osteomyelitis

Answer 400

Osteomyelitis Lesion that infected the bone

Answer 401

Osteosclerosis, Osteophytes, Loss of joint space, Subchondral cysts

Answer 402

Infection of the bone

Answer 403

Benign forward with downward pressure of spine. Though in individuals with severe osteoporosis can occur with something as benign as a sneeze or minor fall.

Answer 404

Neurologic defect: not usually. Levels: all though most common thoracolumbar region. Sex: Female > male. Associated disorders: osteoporosis, renal osteodystrophy, tumors of vertebral body.

Answer 405

Most common in the elderly population after a fall. Also those patients with osteoporosis. Younger patients tend to be from blunt force trauma.

Answer 406

Thinning/weakening of cortex of bone.

Answer 407

Lower than normal bone density without quite meeting osteoporosis criteria.

Answer 408

Osteoporosis Thin white lines and a larger space in between them

Answer 409

Systemic skeletal disorder associated with low bone mineral density

Answer 410

Postmenopausal, Older age, Lower BMI, Exogenous steroid administration, Cushing’s disease, Estrogen deficiency, Inadequate physical activity, Alcoholism

Answer 411

Plasma Cell Myeloma (Multiple Myeloma), Osteogenic Sarcoma (Osteosarcoma), Ewing Sarcoma, Chondrosarcoma

Answer 412

Osteoclastoma (Giant Cell Tumor), Osteoid Osteoma, Unicameral Bone Cyst (Simple Bone Cyst)

Answer 413

Most common primary 'bone' tumor. Though often classified as marrow cell tumor/hematologic cancer. 'M' spike

Answer 414

Age: Median age ~70, Sex: Slight male predominance, Race: Black > White (2:1)

Answer 415

May have bone pain, but usually will see an abnormality or another occurrence on x-ray or labs or something

Answer 416

Labs: CBC, CMP, SPEP w/ IFE. Imaging: Skeletal survey (PET-CT or MRI). Diagnostics: Bone marrow bx is confirmatory

Answer 417

'Punched out' lesions

Answer 418

Age: Most common in 10–20 year olds, Sex: Male > Female (3:1), Race: White > any other races

Answer 419

Most common is bone pain and swelling

Answer 420

Imaging: Typically identified on plain film first. Additional imaging needed for staging. Diagnostics: Bx is confirmatory

Answer 421

'Onion skin' appearance from changes of periosteum

Answer 422

Ewing sarcoma

Answer 423

Osteogenic Sarcoma

Answer 424

Most common malignant primary bone tumor. Predominance in knee or long bones (typically diaphysis-metaphysis junction).

Answer 425

Age: Most common in 10–25 year olds. Second peak in > 65 year olds w/ risk factors. Sex: Slight male predominance.

Answer 426

Most common is bone pain. Initially with activity then at rest. Progressive in nature.

Answer 427

Labs: Alk phos-elevated with increased bone turnover. LDH-if elevated typically means worse prognosis. Imaging: Typically identified on plain film first. MRI usually done secondary to identify extent of tumor. Diagnostics: Bx is confirmatory.

Answer 428

Moth eaten appearance w/ “sunburst”. “Codman triangle” due to elevation of periosteum away from bone.

Answer 429

Benign tumor-like bone lesion. Serous fluid lesion with fibrous membrane.

Answer 430

Age: < 20 years old. Sex: Males > Females.

Answer 431

Site: Most common in long bones. Symptoms-typically asymptomatic and found incidentally on imaging for other reason.

Answer 432

Age: < 20 years old. Location: Metaphysis of long bones. Proximal femur and humerus.

Answer 433

Trauma. Neck or arm: pain/weakness/paresthesia.

Answer 434

Unicameral bone cyst at the left proximal femur

Answer 435

Unicameral bone cyst

Answer 436

unicameral bone cyst Pediatric patient and growth plates present

Answer 437

Right humeral midshaft spiral fracture w/ 25-50% translation

Answer 438

Distal femur fracture with rotation and impaction

Answer 439

Type 1 or Type 3