MSK Flashcards
1
Q
Epiphysis are initially ______
A
Cartilaginous, converting to bone with development of secondary ossification center
2
Q
Primary physis is responsible for
A
Longitudinal growth of the bone
3
Q
Secondary physis is responsible for
A
Spherical growth of epiphysis
4
Q
What are the characteristics of pediatric bone as compared to adults
A
Less dense, more porous and have lower mineral content compared with adults
5
Q
Due to pediatric bones characteristics, it can undergo a greater degree of deformation before breaking. Therefore, what fractures are common in pedia population
A
Greenstick (unicortical) and torus (buckle) fractures, as well as plastic deformation, complete fractures and physeal injuries
6
Q
In newborn, bone marrow is entirely
A
Hematopoietic (red marrow)
7
Q
Bone marrow transformation to fatty (yellow) marrow begins when
A
Within the first year of life and occurs in a predictable manner
8
Q
In the body as a whole, marrow transformation begins where
A
In the periphery, first occurring in the phalanges of the fingers and toes and progressing centrally
9
Q
Order of fatty marrow conversion of epiphysis, metaphysis and diaphysis
A
Epiphyses are first to convert, occurring within 6 months of radiologic appearance of secondary ossification center, continues within diaphysis, followed by metaphysis, with the proximal metaphysis the last to convert
10
Q
On MR, the physis has a ______ appearance
A
Trilaminar appearance
11
Q
The trilaminar appearance of physis in MRI consists of:
A
Zone of cartilage- active chondrocytes;
Zone of provisional calcification- cartilage matrix become calcified;
Primary spongiosa- where woven bone is formed
12
Q
Fibrocartilaginous structure that surrounds the physeal cartilage, low signal on all sequences. This is tightly tethered to the physis and acts as a barrier to disease
A
Perichondrium
13
Q
A thin low SI structure that parallels bone cortex and is loosely attached to the shaft and tightly attached to the perichondrium. Deep to this structure is a rich vascular network that helps to feed the growing metaphyses
A
Periosteum
14
Q
This fracture occurs from longitudinal stress and results in bowing of the bones, with an intact periosteum
A
Plastic deformation
15
Q
Plastic deformation are common in
A
Forearm, tibia, fibula
16
Q
Fractures that results from axial loading on an extremity, occurring at the metaphysis or metadiaphysis. The cortex is compressed and bulges without extension of the fracture to the cortex
A
Buckle or torus fracture
17
Q
Represent 50% of pediatric wrist fractures
A
Buckle fracture
18
Q
Incomplete fractures resulting from perpendicular forces that break one cortex, the side opposite the site of stress
A
Greenstick fractures
19
Q
Most vulnerable to injury during periods of active growth, such as during early adolescence
A
Cartilage
20
Q
Weakest portion of the physeal cartilage
A
Zone of provisional calcification
21
Q
Pathophysiology of chronic physeal trauma
A
Repetitive loading can alter metaphyseal perfusion and interfere with the mineralization of hypertrophied chondrocytes
22
Q
In high intensity runners, chronic physeal injury are common in _____, while in baseball players its common in the ______ which is called little league shoulder and in the _______ in gymnasts (gymnast wrist)
A
Knees- runners
Proximal humerus- baseball players
Distal radiu- gymnast
23
Q
Manifests radiographically as widening of the primary physis, with sclerosis at the margins of adjacent metaphysis
A
Chronic physeal trauma
24
Q
A subset of physeal injuries (either sequela of trauma, infection or ischemia) can lead to cellular disruption and ischemia, giving rise to the development of abnormal osseous connection (bone bridge or bar) between epiphysis and metaphysis. These bone bars can result in limb length discrepancy, angular deformity, or altered joint mechanics
A
Physeal bars
25
The incidence of physeal bar formation is higher after injuries to the
Distal femur, proximal tibia and distal tibia
26
These areas contribute to the greatest proportion of limb growth, and therefore, bars in these regions have the biggest impact on limb length discrepancies
Distal femur and proximal tibia
27
Salter harris type: separation thru the physis, usually thru areas of hypertrophic and degenerating cartilage cell columns
1
28
Salter harris type: fracture thru a portion of the physis that extends thru the metaphyses
2
29
Salter harris type: fracture theu a portion of the physis that extends thru the epiphysis
3
30
Salter harris: fracture across the metaphysis, physis and epiphysis
4
31
Salter-harris type: crush injury to physis
5
32
Growth centers that serve as the attachment sites for tendons and have a physis at its bone interface
Apophyses
33
Apophyseal injuries due to repetitive submaximal stress on an apophysis is called ______ Which causes microavulsions at the chondro-osseous junction with resultant secondary inflammatory changes that attempt to repair the physis leading to overgrowth. Manifests radiographically as widenjng and irregulariy at the physis
Traction apophysitis
34
Little league elbow location of traction apophysitis, due to chronic valgus stress applied to the medial epicondylar apophysis causing medial elbow pain
Medial epicondyle of elbow
35
Location of traction apophysitis in Sinding-Larsen-Johansson syndrome, resulting from excessive force exerted by the patellar tendon on the lower pole of the patella. Causes anterior knee pain
Inferior patellar pole
36
Site of traction apophysitis in Osgood-Schlatter disease, pain at the anterior tibial tuberosity due to repetitive traction of the distal patellar tendon on the maturing anterior tibial tubercle
Tibial tuberosity
37
Location of traction apophysitis in Iselin disease; traction of peroneus brevis tendon on the base of the 5th metatarsal apophysis which presents with lateral foot pain
Base of the 5th metatarsal
38
Site of traction apophysitis in Sever disease; excessive traction of the Achilles tendon onto the calcaneal apophysis causing heal pain
Calcaneus
39
Acute apophyseal injuries are common in active adolescents due to
Inherent weakness of apophyseal cartilage
40
Most common site of pelvic avulsion injuries in adolescents
Ischial tuberosity: hamstrings
41
Iliac crest muscle/tendon attachment
Abdominal musculature
42
Muscle/tendon attachment of anterior superior iliac spine
Sartorius, tensor fasciae latae
43
Muscle/tendon attachment of anterior inferior iliac spine
Rectus femoris muscle
44
Muscle/tendon attachment of greater trochanter
Hip rotators
45
Muscle/tendon attachment of lesser trochanter
Iliopsoas muscle
46
Most common of all pediatric fractures. They may be sen in newborns as a result from birth trauma
Clavicle fractures
47
Vast majority of clavicle fractures occur in
Middle 1/3 of bone
48
In children less than 13 years of age, direct impact to shoulder may lead to a physeal fracture of the ______ clavicle, aka periosteal sleeve fracture
Lateral clavicle
49
Age of the appearance and physeal closure of CRITOE
Capitellum-1 and 14 years
Radial head- 3 and 16 years
Internal (medial) epicondyle- 5 and 15 years
Trochlea- 7 and 14 years
Olecranon- 9 and 14 years
External (lateral) epicondyle- 11 and 16 years
50
Humerus fractures peaks during adolescence secondary to increased sports participation and are most commonly what type of salter harris fracture
Type 2
51
In young children, elbow fractures are commonly _______, with a peak incidence if 5-7 years
Supracondylar fractures
52
Most common mechanism of elbow fractures
FOOSH injury and the hyperextension load
53
In the normal elbow, the anterior humeral line (line drawn along the anterior cortex of the distal humerus) should bisect the
Middle 3rd of capitellum
54
In the setting of supracondylar fracture, the capitellum is displaced _____ to the anterior humeral line
Posterior
55
Have the highest rate of complications among upper extremity fractures
Supracondylar fractures
56
Complications of supracondylar fractures
Neurovascular compromise, compartment syndrome, Volkmann ischemic contractures and cubitus varus
57
If the medial epicondyle is displaced greater than ____ mm, fractures require surgical fixation
5 mm
58
Majority of forearm fractures are located in the
Distal aspect of forearm
59
Fracture of the ulna and dislocation of the radial head
Monteggia fx
60
Radial fracture with disruption of the distal radioulnar joint
Galeazzi fx
61
In older children, the most common carpal bone fx is
Scaphoid fx
62
Scaphoid fx is important to be recognized due to risk of
Avascular necrosis
63
Physeal injury of the proximal femur in which the femoral metaphysis displaces anteriorly, superiorly and laterally with respect to the epiphysis
Slipped capital femoral epiphysis
64
Most sensitive radiographic projection as the slipped epiphysis moves posteriorly and to a lesser extent more medially
Frog leg lateral
65
Presents as widening and irregularity of the proximal physis, relative loss of height of the epiphysis on the AP projection, loss of anterior concavity of the femoral neck, the metaphyseal blanch sign, and metaphyseal cystic change in chronic cases
Slipped capital femoral epiphysis
66
It is sign that presents as crescent-shaped area of increased density at the proximal and medial femoral neck as a result of the projection of the posterior portion of the femoral head
Metaphyseal blanch sign
67
Line drawn along the superior margin of the femoral neck
Kline’s line
68
In normal hips, the Kline’s line will intersect the _____ aspect of the epiphysis. In SCFE, the epiphysis is displaced ______ and the Kline’s line does not intersect the epiphysis or intersect more ______ compared to the other side
Normal- lateral aspect
| SCFE- displaced medially or intersects more laterally compared to the asymptomatic side
69
Treatment for moderate SCFE
In situ pinning
70
In more severe SCFE, treatment is
Open reduction with gentle manipulation of the head of the femur back into its normal anatomic location followed by screw fixation
71
Most common complications following SCFE are
Avascular necrosis and chondrolysis
72
Occurs when cartilage of the inferior pole of the patella is pulled off from the inferior patellar pole, often with a small avulsed osseous fracture
Patellar sleeve fractures
73
On radiographs, it may show a small bone fragment inferior to the lower pole of the patella, patella alta and a joint effusion
Patellar sleeve fracture
74
Seen in children 8-13 y.o and are usually sports-related injuries occuring especially during cycling or skiing
Tibial spine avulsion fractures or tibial eminence fractures
75
Cause of tibial spine avulsion fracture
Weakness of the incompletely ossified tibial eminence compared to the stronger anterior cruciate ligament
76
Most common seen in teenage boys and the injury usually involves active extension of the knee with vigorous contraction of the quadriceps muscles, typically in jumping sports
Tibial tubercle fractures
77
Treatment for fractures confined to the tibial tubercle only
Conservative management
78
Tibial tubercle Fractures that extend into the epiphysis are treated by
Surgical fixation
79
Can occur due to axial loading injuries sustained by young children jumping on trampolines or in similar environments such as bounce houses, generally with larger child/adult
Fractures of the proximal tibial metaphsis or “trampoline fractures”
80
Presents as nondisplaced and non angulated linear or buckle fracture of the proximal tibial metaphysis and can be quite subtle
Trampoline fractures
81
Nondisplaced oblique fracture of the distal tibia that typically presents in childreb between 1 and 4 years of age
Tibial “toddler’s fracture”
82
Nature of trauma is usually mild, such as twisting injury from tripping while walking or running or fall from a modest height. Most of the time no history of trauma can be elicited
Distal Tibial toddler fracture
83
Appears as a faint oblique line crossing the distal tibial shaft terminating medially
Distal tibial toddler fracture
84
Ogden tibial fx classification: fracture of distal aspect of the tibial tubercle near the patellar tendon insertion
1A
85
Ogden tibial fx classification: fragment is displaced anteriorly and proximally
1b
86
Ogden tibial fx classification: fracture extends thru the junction of the ossification of the proximal end of the tibia and tubercle
2a
87
Ogden tibial fx classification: tubercle fragment is comminuted
2B
88
Ogden tibial fx classification: fracture extends to the joint and is associated with discontinuity of the joint surface
3A
89
Ogden tibial fx classification: tubercle fragment is comminuted
3B
90
Second most common physeal injuries in children. Seen only in adolescents, generally between 10 and 16 years of age, when the physis closes in an aymmetric pattern
Distal tibial transitional fractures, triplane and Tillaux fractures
91
Distal tibial physeal closure pattern
Centrally and then proceeds in an anteromedial direction, then posteromedially and finally laterally, which predicts the specific injury pattern
92
Salter 4 fx and have sagittal, transverse and coronal components traversing the physis
Triplane fractures
93
Isolated fracture to the anterolateral portion of the distal tibial epiphysis, a salter 3 injury. Seen in teenagers nearing skeletal maturity, affecting the only remaining portion of the distal tibial physis
Tillaux fractures
94
AP radiographs demonstrate a vertical fracture line withjn the distal tibial epiphysus extending laterally. Lateral radiograph will show an avulsed fragment displaced anteriorly
Tillaux fx
95
Length of displacement of triplane and tillaux fx that would need surgical reduction
More than 2mm
96
Tibial stress fx usually involve what part
Proximal 3rd of the bone and more common posteriorly
97
More sensitive modality in detecting stress fx
MRI
98
These fx are uncommon in active young children however can be seen in adolescents with the so-called “female athlete triad”: osteoporosis, amenorrhea and eating disorders
Insufficiency fx
99
Important cause of foot pain in the young child
Metatarsal and tarsal bones injuries
100
Impaction injuries of the hindfoot in toddlers can cause
Nondisplaced or buckle type fx of talus or calcaneus
101
May occur in young children with forced plantar flexion of the foot, with compression of the cuboid and the 4th and 5th metatarsals
Nondisplaced cuboid fx
102
Bunk bed fracture, sustained when a child falls or jumps from a height (vertical loading with plantar flexion) and there is buckle injury of the proximal aspect of the metatarsal
First metatarsal fx
103
Caused by acute injury or repetitive microtrauma that leads to thinning of the articular cartilage, fragmentation of the subchondral bone, and occasionally, loose bodies
Osteochondral lesions
104
Most common locations for osteochondral lesions
Weight bearing regions of the femoral condyle, capitellum of elbow in throwing athlete and gymnasts, and the ankle
105
“Bone-cartilage conditions” common in young children and comprise a heterogeneous group of injuries to the epiphyses, physis and apophyses
Osteochondroses
106
Result from a disturbance in endochondral ossification and are typically self-limited. Rapid growth, genetics, anatomic considerations, trauma, diet and a defect in vascular supply are proposed etiologies
Osteochondroses
107
Osteochondroses follow a unique series of events, which are:
Necrosis of bone, revascularization, reorganization, with granulation tissue formation and invasion, osteoclast resorption of necrotic segments and ultimately osteoid replacement with mature lamellar bone formed
108
Common location of osteochondral lesions in the knee
Lateral aspect of medial femoral condyle, weight-bearing surface of medial or lateral femoral condyle, patella, trochlea
109
Common OCL in the elbow
Capitellum, lateral aspect of trochlea
110
Common location of OCL in ankle/foot
Medial aspect of talus, lateral aspect of talus, central talar dome, distal tibia, subtalar facet, talar head
111
Osteochondrosis of the femoral head and is common cause of hip pain and limp in preadolescent children
Legg-Calve’-Perthes disease
112
Peak age and sex predilection of legg-calve-perthes disease
5-6 years, more common in boys
113
Most cases of legg-calve-perthes are unilateral or bilateral?
Unilateral
114
Early in its course of disease, radiographs may demonstrate widening of the medial joint space and asymmetrically smaller femoral epiphysis of the affected side with sclerosis. Physis may become indistinct, lucency may be seen within the femoral metaphysis, overtime the epiphysis may begin to fragment and flatten. Coxa magna of the femoral neck develops
Legg-calve- perthes disease
115
Prognostic indicators in legg-calve-perthes disease
Extent of osteonecrosis, amount of lateral extrusion, physeal involvement and metaphyseal abnormalities
116
Radiographic findings indicative of subsequent growth disturbance in legg-calve-perthes disease
Physeal abnormalities and metaphyseal lucencies
117
True or false: the younger the age of presentation in legg-calve-perthes disease, the more benign the course
True
118
asymmetrical, circumferential enlargement and deformation of the femoral head and neck.
Coxa magna of femoral neck
119
Self limiting osteochondrosis of the developing capitellum that affects children younger than 12 years. Most commonly seen in baseball pitches and falls into the spectrum of “little leaguers elbow”
Panner disease
120
Presumed cause of panner disease
Repetitive chronic impaction injury to the tenuous blood supply of the capitellum
121
True or false: the entire capitellum is usually involved in panner disease
True
122
Radiographically, it appears as demineralization of the capitellum with loss of the normally sharp cortical margins, followed by sclerosis and loss of volume and ultimately progressing to frank fragmentation
Panner disease
123
True or false: the overlying articular cartilage of capitellum is not affected in panner disease
True
124
Osteochondrosis of the tarsal navicular bone which occurs between 4 and 9 years of age with a higher prevalence in boys
Kohler disease
125
Sclerosis and narrowing/flattening of the tarsal navicular bone
Kohler disease
126
Osteochondrosis of the metatarsal head
Freiberg’s infarction
127
Freiberg’s infarction commonly affects the
Second metatarsal head, followed by the 3rd metatarsal head
128
On radiographs, it appears as widening of the metatarsophalangeal joint with collapse and sclerosis of the metatarsal head. This may be associated with loose body formation, dorsal spurring and consequent thickening of the metatarsal shaft
Freiberg’s infarction
129
Non accidental trauma such as skull fractures, rib fractures and displaced metaphyseal injuries predominate at what age
Infancy
130
Long bone injuries from non accidental trauma predominate at what age
After 1 year of age
131
Fractures with high specificity for abuse include
Classic metaphyseal lesions, rib fractures (especially posterior), scapular fractures, spinous process fx, and sternal fractures
132
Aka corner fractures or bucket handle fractures
Classic metaphyseal lesion
Salter-Harris II
133
Most frequently encountered long bone injury in abused children and are commonly seen in what bones
Distal femora, proximal and distal tibia and proximal humeri
134
True or false: CMLs may heal without significant callus or subperiosteal new bone formation which makes dating assessment difficult
True
135
When should follow up skeletal surveys be done in non accidental trauma patients as this will increase the sensitivity of depicting subtle or occult fractures
2 weeks after
136
3 major pathways of bone infection
Hematogeneous, direct inoculation and via extension from adjacent soft tissue infections
137
In children, acute osteomyelitis is most commonly acquired _______
Hematogeneously
138
Most common organisms involved in osteomyelitis in children
Staphylococcus aureus, B-hemolytic streptococcus and streptococcus pneumoniae, E.coli and pseudomonas aeruginosa
139
Acute hematogeneous osteomyelitis primarily involves the
Metaphyses of long bones or metapgyseal equivalents (osseous regions adjacent to a physis)
140
Metaphyses of long bones are common site for acute hematogeneous osteomyelitis due to
Presence of slow-flowing venous sinusoids
141
Complications of acute osteomyelitis
Subperiosteal abscess and ultimately dissecting into the adjacent soft tissues, thrombophlebitis, septic emboli, growth arrest due to bone bar formation, pathologic fx and chronic osteomyelitis
142
Most cases of epiphyseal osteomyelitis or chondritis occur in children of what age
Younger than 4 years
143
Epiphyseal osteomyelitis or chondritis are best demonstrated as
Avascular/non enhancing regions of affected cartilage
144
Thrombophlebitis as a complication of acute osteomyelitis is typically associated with
Methicillin resistant S. Aureus
145
Caused by hematogeneous bacterial seeding or by direct extension into the joint space in the setting of osteomyelitis or adjacent soft tissue infection
Septic arthritis
146
In very young infant, septic arthritis present as multifocal involvement, with the ____ as the most frequent site
Hip
147
True or false: imaging cannot reliably differentiate a reactive effusion (toxic synovitis) from septic arthritis
True
148
A self-limited disease with no known long term sequela. It is a common entity, particularly involving the hip in young children between 3 and 10 years of age. Children appear nontoxic and present with pain and limp and are usually afebrile with normal to marginally elevated WBC and inflammatory markers. Parents often report a preceding viral or bacterial upper respiratory or GI illness (within 4-5 weeks)
Toxic synovitis or transient/reactive synovitis
149
Treatment for toxic synovitis or transient/reactive synovitis
Rest and analgesics and symptoms begin to resolve within 24-48 hours
150
Very common benign tumor/tumor like lesion of bone and occur in approximately 1-2% of population. Thought to represent a developmental defect of bone growth secondary to an injury to the perichondrium, rather than a true tumor
Osteochondroma
151
Condition in which physeal cartilage herniates through this defect and growth results in an osseous excrescence with continuity to the underlying medullary canal and cortex, with an overlying cartilagenous cap
Osteochondroma
152
Most commonly affected part in osteochondroma
Lower extremity, commonly in the knee
153
Radiographic hallmark of an osteochondroma
Osseous excrescence with continuity of the cortex and medullary space from the underlying bone into the osteochondroma
154
When the osteochondroma is pedunculated, the lesion usually points where
Away from the nearest joint
155
If the cartilageneous cap of osteochondroma is ____ cm in thickness, the very rare transformation to chondrosarcoma should be considered
More than 1.5 cm
156
Multiple osteochondromas are seen in patients with
Hereditary multiple exostoses or familial osteochondromatosis or diaphyseal aclasis
157
A distinct disorder secondary to osteochondroma development from an epiphysis that predominantly affects the lower extremities
Trevor disease or dysplasia epiphysealis hemimelica
158
Uncommon benign cartilaginous neoplasms that characteristically arise eccentrically in the epiphyses or apophyses of children, with 70% occurring in the humerus, femur and tibia
Chondroblastoma
159
Well-defined lucent lesions with smooth or lobulated borders and a thin sclerotic rim with perhaps endosteal scalloping
Chondroblastoma
160
Treatment of chondroblastoma
Curettage and packing of the lesion or radiofrequency ablation
161
Disorder resulting from the proliferation and accumulation of the Langerhans cell, a histiocyte. Cause is unknown altho some studies suggest abnormal immune regulation as the underlying factor and others consider it a neoplastic process
Langerhans cell histiocytosis
162
Localized form of LCH usually presents in children age
10 to 12 y.o
163
LCH can involve any bone, however there is a predilection for
Flat bones and more than half of the lesions in localized LCH occur in the skull, mandible, pelvis and ribs
164
When there is long bone involvement, LCH usually occurs within the _____ with the ______ being the most common long bone site
Diaphsysis and femur
165
Mandibular involvement in this condition may lead to floating tooth appearance due to the destruction of alveolar bone
Langerhans cell histiocytosis
166
Management of langerhans cell histiocytosis
Curettage, ablative techniques and direct intralesional methylprednisolone injection, disseminated disease may be treated with steroids and chemotheraphy
167
Most common malignant primary tumor in children and young adults
Osteosarcoma
168
Gender predominance and age of peak incidence of osteosarcoma
Male, 15-25 years of age
169
Types of osteosarcoma
Intramedullary, surface, extraskeletal and secondary osteosarcoma
170
Most common type of osteosarcoma and is referred to as conventional osteosarcoma
High-grade intramedullary type
171
These osteosarcomas arise from the medullary cavity of the metaphysis of long bones, most commonly in the distal femur and proximal tibia
High grade intramedullary osteosarcoma
172
Typically appears as a mass that contains fluffy, cloudlike opacity which represents osteoid matrix production. Lesions usually have a mixed lytic and sclerotic appearance with cortical erosion and destruction. Given the aggressive growth pattern, there is often spiculated (sunburst) periosteal new bone and periosteal elevation is frequently seen resulting in Codman triangles
Osteosarcoma
173
Skull lesions appear as beveled edge or “hole in hole” appearance due to unequal involvement of the inner and outer tables of the calvarium
Langerhans cell histiocytosis or eosinophilic granulomatosis
174
An uncommon subtype of intramedullary osteosarcoma and is often confused with aneurysmal bone cysts
Telangiectatic osteosarcoma
175
Type of osteosarcoma that tends to occur around the knee and contains large cystic cavities filled with blood or necrotic tumor, and the walls/septations contrain malignant cells that produce osteoid
Telangiectatic osteosarcoma
176
Most common surface osteosarcomas
Parosteal and periosteal subtypes
177
Most common type of surface osteosarcoma and tends to occur in older patient population
Parosteal subtype
178
Intermediate-grade osteosarcoma lesions which are thought to arise from the deep layers of the periosteum and arise in patients of the same age as conventional osteosarcoma
Periosteal osteosarcoma
179
Type of osteosarcoma that tend to arise in the diaphysis with the femur and tibia representing the most common location
Periosteal osteosarcomas
180
Treatment of osteosarcoma
Combination of chemotherapy and surgery
181
True or false: osteosarcoma is not radiosensitive
True
182
Small, round, blue cell tumor of childhood and belongs to the family of tumors including extraosseous Ewing sarcoma, Askin tumor and primitive neuroectodermal tumors (PNET)
Ewing sarcoma
183
Second most common primary malignant bone tumor in children and adolescents with an annual incidence of approximately 200 cases
Ewing sarcoma
184
Ewing sarcoma is most frequent in the ____ decades of life, with peak incidence between what age
3 decades of life, peak between 10-20 years of age
185
Gender predominance of ewing sarcoma
Male
186
True or false:ewing sarcoma is uncommon in african-american and asian populations
True
187
Ewing sarcoma most commonly occurs in what bones
Extremities, ribs and pelvis
188
Most commonly involved bone in ewing sarcoma
Femur
189
Ewing sarcoma Lesions in long bones typically arise in the
Metadiaphysis and diaphysis
190
Has an aggressive appearance with bone destruction leading to a moth-eaten or permeative pattern. There is usually periosteal reaction which may appear lamellated (onion-skin like). An associated soft tissue mass is also a common finding and the mass tends to be much larger in size in comparison to the amount of underlying bone destruction
Ewing sarcoma
191
Most common malignancy of children
Acute leukemia
192
Most common type of leukemia
Acute lymphoblastic leukemia
193
Peak incidence of ALL
2-3 years of age
194
Most common skeletal finding in leukemia
Diffuse demineralization
195
So called “leukemic lines” seen in 50% of patients with skeletal findings. They are non specific and seen as a uniform and regular lucency across the width of metaphysis in those bones associated with rapid growth such as the distal femurs, proximal tibia/humeri, vertebral bodies and iliac crests
Transverse lucent metaphyseal bands
196
Benign vascular tumors and is the most common vascular tumor of infancy
Hemangioma
197
Vascular lesion that follows a characteristic clinical pattern:they are not present at birth, although sometimes a precursor lesion such as discoloration or macule may be present. There is rapid growth after birth during the proliferative phase, with a peak at about 1 year of age. An involuting phase follows with spontaneous regression and decrease in size over many years. Final stage is a fibrotic stage with small residual fibrofatty tissue remaining for life
Hemangioma
198
Most commonly involved organ in infantile hemangioma
Skin followed by the liver
199
Infanfile hemangioma are associated with what syndromes
```
PHACE sydrome (posterior fossa brain malformations; hemangiomas of the face, neck or scalp;arterial anomalies; coarctation of the aorta and cardiac defects; and eye abnormalities)
LUMBAR syndrome (lower body infantile hemangiomas, urogenital anomalies, ulceration, myelopathy, bony deformities, anorectal malformations, arterial anomalies and renal anomalies)
```
200
Congenital hemangiomas can be distinguished from infantile hemangiomas clinically as they at birth because of the
Proliferative phase occurs in utero
201
Primary diagnostic imaging modality for hemangiomas
Ultrasound
202
Spectral doppler of hemangiomas will show
Low resistance arterial waveforms
203
On color doppler imaging, hemangiomas appear as
Marked vascularity with 5 or more vessels per square centimeter
204
As hemangiomas involutes, it will appear
Show decreased vascularity and increased echogenicity
205
Of note, this should not be present in hemangiomas
Perilesional edema
206
Treatment for hemangioma
No tx required unless for loss of function or cosmetic issues, medical tx with propanolol and possibly embolization or surgery may be performed
207
Aka pseudotumor of infancy or sternomastoid pseudotumor.
Fibromatosis coli
208
Usually manifests at about 2 weeks of life with a palpable mass in the sternocleidomastoid muscle
Fibromatosis colli
209
Fibromatosis colli is usually unilateral or bilateral?
Unilateral
210
True or false: fibromatosis colli is more commonly right-sided and can cause torticollis
True
211
Majority of cases of fibromatosis colli resolve by what age
2 years of age
212
Treatment for fibromatosis colli
Conservative: stretching and physical therapy
213
Heterogeneous group of disorders which are characterized by abnormal bone and cartilage growth
Skeletal dysplasias
214
Long bone dysplasias affecting the proximal portions of extremities
Rhizomelia
215
Dysplasias affecting the middle portion of long bones
Mesomelia
216
Dysplasias affecting the distal portion of long bones
Acromelia
217
Shortening of the entire extremity
Micromelia
218
Most common non lethal skeletal dysplasia and patients have normal mentation and life span
Achondroplasia
219
Patients have rhizomelia, frontal bossing and small/narrow foramen magnum, thorax is small with shortened ribs, narrowing of rhe interpedicular distance particularly in the more caudal segments of lumbar spine and posterior vertebral body scalloping and gibbus deformity. Iliac wings may be rounded, with flat acetabular roofs, narrow sacrosciatic notches and a champagne glass-shaped pelvic inlet, hands show brachydactyly with trident configuration. Femurs show scooped out appearnce while the distal femur has a deep notch in the central growth plate (chevron deformity) and there is fibular overgrowth
Achondroplasia
220
On of the most common lethat skeletal dysplasia, with features such as “clover-lead” skull due to craniosynostosis, curved long bones including “French Telephone reciever” appearance to the femurs, platyspondyly, short rivs and handlebar clavicles and micromelia
Thanatophoric dwarfism
221
Presence of this can help distinguish thanatophoric dwarfiam from other forms of dwarfism
Platyspondyly
222
Group of metabolic disorders that involve the defective activity of the lysosomal enzymes which blocks degradation of mucopolysaccharides. Most commin subtypes are Hunter, Hurler, Sanfilippo and Morquio syndromes
Mucopolysaccharidoses
223
Common features include enlarged skull with J-shaped sella, paddle or oat-shaped ribs, beaking of the thoracolumbar vertebral bodies sometimes with gibbus deformity. Iliac wings are flaired and small with inferior tapering and steep acetabular roofs. Metacarpals show proximal tapering
Mucopolysaccharidoses
224
Inherited disorder of connective tissue characterized by increased bone fragility and low bone mass. Clinical findings include blue sclera, dentinogenesis imperfecta, skin hyperlaxity and joint hypermobility
Osteogenesis imperfecta
225
Most common type of osteogenesis imperfecta
Mild type 1 disease
226
Main radiographic features include diffuse demineralization, fractures and deformities. Fx typically invloves the long bones and spine. Popcorn calcifications are also described at the metaphsysis/epiphysis which are secondary to ossification of the displaced and fragmented physis
Osteogenesis imperfecta
227
Rare bone disease that results from a failure of osteoclasts to resorb bone. Decreased osteoclastic activity leads to decreased elasticity of bone, impaired repair functions and increased risk of fx. Greater risk of infection and delayed union
Osteopetrosis
228
Hallmark of osteopetrosis
Increased density in the medullary portion of bone with relative sparing of the cortices
229
Type of osteopetrosis that has uniform sclerosis of the long bones, skull and spine
Phenotypic variant Type 1
230
Type of osteopetrosis that has a the “bone-within-bone” appearance and sclerosis of the skull base
Phenotypic type 2
231
Sandwich vertebra or picture frame vertebral bodies
Phenotypic type 2 osteopetrosis
232
Relatively common dysplasia findings and include: wide sutures, numerous wormian bones, absence/hypoplasia of clavicles and pubic bones, posterior wedging of thoracic vertebral bodies, numerous pseudoepiphyses of metacarpals and tapered distal phalanges
Cleidocranial dysplasia
233
Aka infantile cortical hyperostosis and is characterized by presentation before the 5th month of life, hyperirritability, soft tissue swelling and bone lesions, particularly mandible involvement
Caffey disease
234
Long bones, clavicle, scapulae and ribs can also be involved and demonstrate diaphyseal new bone formation sparing the epiphyses and metaphyses
Caffey disease
235
True or false: caffey disease is a self-limiting process with bone remodeling and resorption occurring by age 2
True
236
Aka von Recklinghausen disease, an autosomal dominant disorder due to mutation or deletion of NF1 gene
NF1
237
Chromosome involved in NF1
17
238
Characterized by formation of neurofibromas and abnormalities related to mesodermal dysplasia
NF1
239
Most common complication of NF1
Spinal deformities, particularly scoliosis
240
Imaging characteristics include vertebral scalloping, neuroforaminal widening, transverse process spindling and rib penciling
NF1
241
Posterior vertebral scalloping aside from NF1, can also be seen in
Marfan syndrome, achondroplasia and associated with spinal tumors
242
Posterior vertebral scalloping in NF1 is due to
Bone weakness and circumferentual dilation of dural sac
243
May be one of the earliest manifestations of NF1, typically presenting within the first few years of life
Tibial bowing
244
Tibial bowing in NF1 is usually at what direction
Anterolateral, tends to involve the distal diaphysis, resulting in limb shortening
245
Benign positional bowing of tibia is directed
Posteromedially
246
Characterized by impaired mineralization and ossification of cartilage and osteoid and delayed endochondral ossification in children. Results in excessive physeal cartilage, growth failure and skeletal deformities. Risks include exclusively breastfed infants and African americans
Rickets
247
Patients with this condition manifest short stature, failure to thrice, weakness and bowing deformities
Rickets
248
Earliest manifestation of rickets
Demineralization
249
Findings in rickets are most prominent in what areas
Metaphyses of bones with the greatest growth: distal radius and ulna, distal femur, proximal tibia, proximal humerus and anterior rib ends
250
One of the earliest changes at the physis in rickets is the
Loss of the zone of provisional calcification
251
Seen in rickets due to accumulation of unossified cartilage
Widening, fraying and cupping of metaphysis
252
True or false: distal ulnar metaphysis may normally appear cupped and should not be mistaken for rickets if the distal radial metaphysis appears normal
True
253
Following vitamin D supplementation in rickets, changes of healing can be seen on radiographs within how many months
2-3 months, with mineralization of the zone of provisional calcification representing one of the earliest findings
254
Due to a chronic deficiency of vitamin C, which is required for proper biosynthesis of collagen
Scurvy
255
Pathophysiology of scurvy
Abnormal collagen production leading to vascular fragility along with abnormal bone matrix which occurs in the same areas of greatest bone growth as seen in rickets
256
Classic signs of scurvy
Frankel line, trummerfeld zone or scurvy line, pelkan spur and wimberger ring sign
257
Classic scurvy sign with irregular growth plate with a dense band along the metaphyseal side at the zone of provisional calcification. Peripheral extension of this line results in a pointed, “beaked” contour of the metaphysis
Frankel line
258
Lucent line adjacent to the Frankel line, more diaphyseal in location is known as the ______ which represents accumulated hemorrhage
Trummerfeld zone or scurvy line
259
A healing metaphyseal pathologic fracture seen as a density adjacent to the metaphysis in scurvy
Pelkan spur
260
A thin scleroric cortex surrounding a lucent epiphysis in scurvy
Wimberger ring sign
261
Altho radiographic findings in scurvy are non specific, these findings when present should raise suspicion for scurvy
Diffuse symmetric bilateral metaphyseal changes with adjacent soft tissue edema and periosteal reaction
262
Most common form of heavy metal poisoning
Lead poisoning
263
Lead lines is due to
Lead ion deposition in the zone of provisional calcification
264
Pathophysiology of lead poisoning
Inhibits osteoclastic remodelling but does not affect osteoblasts and results in increased thickness and trabeculae
265
Difference between lead lines and normal variant dense metaphyseal bands
Lead lines can be distinguished clearly from the zone of provisional calcification once interval growth has occurred, whereas normal variant dense metaphyseal bands are always contiguous with the zone of provisional calcification
266
Congenital disorder which ranges from hypoplasia to complete absence of proximal femur
Proximal focal femoral deficiency
267
Associated deformities with proximal focal femoral deficiency
Fibular hemimelia (up to 80%), shortened tibia, hypoplastic patella, agenesis of the cruciate ligaments, deficiency of lateral rays of the foot, talocalcaneal coalition and equinovalgus or equinovarus deformity
268
Condition with excessive medial bowing of tibia, tibia vara. Result of abnormal stresses on the posteromedial proximal tibial physis, leading to delayed endochondral ossification of the medial physis. This results in asymmetric growth and varus angulation
Blount disease
269
Most common type of blount disease and is diagnosed before 4 years of age
Infantile
270
True or false: there is an association between increased body weight and blount disease
True
271
Diagnosis is made on standing radiographs of lower extremities, genu varum is present as measured by the angle of intersection of lines along the midshaft of femur and tibia. There is depression, irregularity, fragmentation and beaking of proximal medial tibial metaphysis and deficiency of medial proximal tibial epiphysis
Blount disease
272
Characteristic of Blount disease that will distinguish it from physiologic bowing
Unilateral and asymmetric
273
Tx for blount disease
Surgical with hemiepiphysiodesis and guided growth with osteotomy
274
An abnormal fibrous cartilaginous or bony connection between 2 of the tarsal bones
Tarsal coalition
275
Most common tarsal coalitions
Talocalcaneal and calcaneonavicular
276
True or false, tarsal coalitions are bilateral in 50% of cases
True
277
Calcaneonavicular coalitions are best seen on what view
Oblique view
278
Anteater’s nose sign: elongated appearance of anterior-superior calcaneus extending toward the navicular is seen in
Calcaneonavicular coalition
279
Foot is is fixed in adduction, supination and in varus. Calcaneus, navicular and cuboid bones are medially rotated relative to the talus. Forefoot is pronates in relation to the hindfoot which gives rise to pes cavus
Congenital talipes equinovarus (clubfoot)
280
Talocalcaneal coalitiona on lateral radiographs
Talar beaking, poor visualization of talocalcaneal joint space, rounding of lateral talar process and lack of depiction of the middle facet on lateral radiographs
281
C-sign can be seen on lateral radiographs as well as C-shaped line that outlines the medial talar dome and posterior-inferior sustentaculum
Talocalcaneal coalition
282
Treatment for coalitions
Casting, physical therapy, orthotocs, anti-inflammatory medications
283
Four features in weight bearing radiographs of club foot
Hindfoot equinus with a lateral talocalcaneal angle less than 35 degrees, hindfoot varus on AP radiographs with a talocalcaneal angle of less than 20 degrees, metatarsus adductus with adduction and varus deformity of forefoot and talus to first metatarsal angle greater than 15 degrees, as well as medial subluxation of rhe navicular on talus
284
Lateral view appearance of clubfoot
Near parallel arrangement of talus and calcaneus
285
Includes a spectrum of abnormalities ranging from mild to markedly abnormal development of femoral head and acetabulum
Developmental dysplasia of hip
286
What side of the hip is more commonly involved in DDH
Left
287
Risk factors for DDH
Breech position in utero, oligohydramnios, family hx, female gender, first born
288
Hip click or clunk with upward force and adduction at the hip in DDH
Ortolani test
289
Hip click or clunk in downward force and adduction in young infants
Barlow test
290
Primary imaging modality in screening for and evaluating DDH in children younger than 6 months of age
Ultrasound
291
A normally positioned hip is how many percent covered by acetabulum
More than 50%
292
Angle formed by the cortex of the ilium and acetabular roof
Graf alpha angle
293
Normal alpha angle in hip
More than 60 degrees
294
In older infants, AP radiographs of pelvis in neutral position allows for
Morphologic assessment of hips
295
In older infants, frog leg lateral view can help determine
Whether a subluxated hip reduces
296
Radiograph findings in DDH
Delayed femoral head ossification, shallow acetabulum, abnormal position of femoral head relative to the acetabulum
297
Treatment of DDH for patients up to 6 months
Closed reduction with Pavlik harness
298
Treatment of DDH in older infants
Closed surgical reduction with hip spica casting
299
Excessive abduction in DDH tx is postulated to lead to
AVN
300
Caused by traction injury during birth leading to brachial plexus palsy
Shoulder dysplasia
301
Risk factors for shoulder dysplasia
Shoulder dystocia, breech presentation, forceps delivery and fetal macrosomia
302
Asymmetrically small, aspherical and flattened humeral head. The glenoid will appear dysplastic with a hypoplastic scapula and there is glenoid retroversion
Shoulder dysplasia
303
Horizontal line thru both triradiate catilages
Hilgenreiner line
304
In hilgenreiner line, femoral head should line where
Within the inferior medial quadrant of the acetabulum
305
Vertical line intersecting the lateral rim of the acetabular roof, drawn perpendicular to Hilgenreiner line
Perkins line
306
C-shaped line along the inferior aspect of pubic ramus and continuing to the inferior border of the femoral neck
Shenton line
307
Angle formed by a line through the acetabular roof and Hilgenreiner line
Acetabular angle
308
In neonates, acetabular angle should be,
Less than 30 degrees and decreased as the patient ages, to less than 22 degrees at 1 year of age and older
309
Angle formed from a vertical line through the center of the ossified femoral head and line along the lateral margin of the acetabular roof
Anterior-center edge angle
310
Center-edge angle less than 20 degrees us indicative of
DDH
311
Treatment of shoulder dystocia
PT and botulinum toxin injection or closed reduction
312
Treatment of shoulder dystocia in older children
May require surgery and nerve grafting may be performed in those with multiple nerve root avulsions
313
Aka constriction band syndrome comprises a wide range of congenital anomalies where fetal parts get entrapped with fibrous bands if disrupted amnion which typically leads to limb and digital amputations and contriction rings
Amniotic band syndrome
314
Amniotic band syndrome is caused by
Vascular insult that occurs during
| early embryogenesis
315
An umbrella term that encompasses all forms of inflammatory arthritis that begin the age of 16, persist for more than 6 weeks and are of unknown etiology
Juvenile idiopathic arthritis
316
Hallmark feature of all subtypes of JIA
Joint inflammation
317
Pathophysiology of JIA
Inflammation of synovial lining, synovial hyperplasia with increased vascularity, resulting in a high cellular inflammatory pannus, pannus will eventually erode into the overlying cartlage and bone as a result of antibody deposition and degradative enzymes, leading to articular destruction
318
Role of ultrasound jn JIA
Assess bone surface, for rapid and inexpensive method for evaluating synovial proliferation, joint fluid, cartilage thickness, cortical erosions, tenosynovitis and enthesitis
319
Best noninvasive imaging modality to evaluate for inflammation of the joints, tendons and entheses in JIA. Useful in assessment of bone marrow edema as well as assessment of intra-articular structures that cannot be accessed with an ultrasound probe
MRI
320
Goal of intervention for JIA
Suppress synovial and entheseal inflammation in order to prevent cartilage and bone damage
321
Treatment for JIA
Both systemic therapy as well as direct medicinal joint injections
322
X-linked congenital bleeding disorders caused by the absence or decrease of clotting factor VIII OR IX
Hemophilic arthropathy
323
Most frequent manifestation of hemophilic arthropathy
Joint bleeding
324
One of the earliest complications of hemarthrosis
Synovitis
325
Synovitis is characterized by
Synovial hypertrophy and inflammation with neoangiogenesis and subsequent bleeding
326
Commonly involved joints in hemoarthropathy
Knee, elbow, ankle, hip and shoulder
327
Classic findings in hemarthropathy of the knee
Widened intercondylar notch, squared margins of patella, bulbous femoral condyles with flattened surfaces
328
Classic findings in elbow hemarthropathy
Enlargement of radial head with a widened trochlear notch
329
Findings in ankle hemarthropathy
Ankle deformity may arise due to undergrowth of the lateral aspect of distal tibial epiphysis
330
Idiopathic inflammatory disorder of children and young adults that is characterized by exacerbations and remissions of nonbacterial osteomyelitis
Chronic recurrent multifocal osteomyelitis
331
CRMO may be seen in conjunction with what other inflammatory conditions
Psoriasis and IBD
332
Treatment for CRMO
anti-inflammatory therapies
333
True or false, CRMO remains a disease of exclusion since there is no laboratory confirmation test
True
334
Characteristic locations of CRMO
Mandible, medial aspect of clavicle, metaphysis of lower extremities, rib, vertebral, sacroiliac joint and pelvic (metaphyseal equivalents
335
Group of genetic disorders that posses an abnormality within the hemoglobin molecule
Hemoglobinopathies
336
2 most clinically relevant hemoglobinopathic conditions within the pediatric population
Sickle cell disease and beta thalassemia
337
Results from a single point mutation in the beta chain of the hemoglobin molecule. This causes the hemoglobin molecules to become sticky with abnormal polymerization, deforming the rbc into classic sickle shape, resulting in microvascular occlusion and ischemic events
Sickle cell disease
338
Sickle cell patients maintain red marrow in the majority of
Axial and appendicular skeleton, including ankles and wrists
339
Can cause widened medullary spaces, thinned cortices, demineralization and coarsened trabecular pattern in sickle disease
Red marrow persistence in sickle disease
340
“Hair on end” pattern in the skull, which appears as widening of the diploic space of calvarium and thinning of the inner or outer calvarial table
Sickle cell disease
341
progressive cortical thinning and smooth biconcavity may develop in the vertebral bodies due to weakened bone and pressure effect from the adjacent disc in sickle cell disease
Codfish vertebrae
342
Sharper depressions in the central portions of the endplates due to focal infarction can be seen in sickle cell disease causing this appearance of vertebrae
Lincoln log or H-shaped vertebral bodies
343
Sickle cell dactylitis or “hand-foot” syndrome will affect approximately how many percent of pediatric patients with majority of patients are at what age
50% of pediatric patients, 6 months to 2 years of age
344
Areas particularly prone to infarction in sickle cell disease
Small tubular bones of hands and feet
345
Why is painful crisis in sickle cell dactylitis late to manifest
In these bones, the transformation of red marrow to yellow marrow occurs much later in sickle cell patients, making episodes uncommon after 6 years of age
346
A characteristic serpiginous “double line” is described which consists of a hyperintense inner line (inflammatory response) and a hypointense outer border (reactive bone interface) in long bones of patients with sickle cell disease. Cortical infarctions can also occur, resulting in cortical thickening or “bone-in-bone” appearance secondary to layered subperiosteal new bone formation
Sickle cell osteonecrosis
347
Sickle cell-related epiphyseal osteonecrosis is most common in what areas
Humeral and femoral heads and often bilateral
348
Later stage of epiphyseal infarction include what radiographic findings
Crescentic subchondral lucency and articular irregularity and subchondral collapse and fragmentation
349
Later stage epiphyseal infarctions in sickle cell disease are often more pronounced in weight-bearing joints such as the
Hip, where articular deformity may lead to secondary degenerative changes
350
Osteomyelitis in sickle cell patients is usually due to what organisms
Salmonella, or other gram negative organisms such as E. Coli
351
Genetic disorders affecting the Beta-globin gene that result in reduced or absent synthesis of beta globin chains, ultimately affecting erythropoiesus and red cell lifespans, resulting to anemia, hepatosplenomegaly, cardiomegaly with CHF and significant marrow expansion with secondary osseous deformities
Beta thalassemia
352
Osseous imaging findings in beta thalassemia are due to
Extramedullary hematopoiesis as well as a result of iron chelation therapy which is distinctly compared with sickle cell disease
353
In this blood condition, osseous changes occur due to severe anemia and a massive increased demand for rbc which produce diffuse marrow expansion of the calvarium, spine, pelvis and nearly all tubular bones
Beta thalassemia
354
Diffuse marrow expansion in beta thalassemia results in these radiographic findings
Cortical thinning and resorption of cancellous bone with coarsening of trabecular markings
355
Commonly involved bone in beta thalassemia
Ribs; expansion of head and neck of ribs
356
Calvarial thickening in beta thalassemia is most prominent in what part
Frontal bones with thinning of outer table and prominent subperiosteal spicules, creating hair on end appearance
357
Pathognomonic facial appearance of thalassemia due to marked marrow expansion in calvarium causing diminished pneumatization of paranasal sinuses. Marrow expansion in the maxillary bones may ventrally displace the central incisors and laterally displaces the orbits
Rodent facies
358
True or false: thalassemia patients who have not undergone transfusion therapy demonstrate an infantile marrow distribution
True
359
In thalassemia patients receiving transfusions along with chelation therapy, iron deposition will be predominantly within the ______ skeleton with hematopoietic marrow in the remainder
Axial skeleton
