This document discusses several normal anatomical variants and physiological processes in the pediatric skeleton that can be mistaken for fractures or other pathologies if not properly recognized. It describes synchondroses in the sphenoid bone, cervical spine, and ischiopubic region that are present in infants and children. It also discusses transient findings like metaphyseal bands, periosteal new bone formation, cortical irregularities, and pseudosubluxation that are normal in young patients. Distinguishing these normal variants from actual fractures or diseases is important to avoid unnecessary treatment or invasive diagnostic testing.

2. Dr.RAJEEV.K.S

4. SYNCHONDROSIS
 An infant is born with
three synchondroses of the
sphenoid bone.
 The frontosphenoid
synchondrosis
 the intersphenoid
synchondrosis
( close by several months to
1 year of life.)
 The spheno-occipital
synchondrosis, , may
remain patent until early
adulthood

5. Sphenoid Bone Synchondroses
 These synchondroses
generally are not attended to
by the orthopaedic surgeon
 except when assessing the
cervical spine for trauma.
 The most common question
then asked is “Do these
synchondroses represent
basilar skull fractures
 ” Knowing the existence of
these synchondroses and
when they close eliminates
the need to do other time-
intensive and expensive
studies

6. Body of C2 and Odontoid
Synchondrosis
 The synchondrosis
between the odontoid
and body of C2 may
simulate a fracture
 from birth until it
closes, between ages 3
and 7 years
 When it is partially
fused it may appear as an
incomplete fracture of
the odontoid

7. Body of C2 and Odontoid
Synchondrosis
 . Assessment of the
odontoid's alignment with
the body of C2 then
becomes extremely
important.
 If the alignment is not
anatomic,
 further evaluation with
computed tomography
(CT) or magnetic
resonance imaging (MRI)
is indicated

8. Synchondroses between Vertebral
Bodies and Neural Arches
 These synchondroses
appear as lucent lines
between the vertebral
bodies and neural arches
from birth until mid-
childhood,
 They become particularly
noticeable on oblique
views of the infant's
cervical spine and may
mimic fractures.

9. Cervical Spine Pseudosubluxation
 Owing to ligamentous
laxity and horizontally
positioned facet joints
 the upper cervical spine in
infants and children may
appear to subluxate during
flexion.
 When multiple cervical
vertebral bodies are
involved, physiologic
subluxation is clearly the
diagnosis

10. Cervical Spine Pseudosubluxation . Subluxation limited to C2 on C3,
however, may be physiologic or
associated with a hangman's
fracture.
 To differentiate these conditions,
Swischuk[9] devised the posterior
cervical line.
 This line is drawn from the
anterior cortex of the C1 posterior
ring to the anterior cortex of the
spinous process of C3 (Fig. 10-7).
 If the line misses the anterior
cortex of the spinous process of C2
by more than 2 mm, a true
dislocation is present.
 This line should be used only to
assess C2-3 subluxation and
should not be applied at any other
level.
 Moreover, a normal posterior
cervical line does not exclude
significant ligamentous injury

11. ISCHIOPUBIC SYNCHONDROSIS: COMMONLY CONFUSED WITH
INFECTION OR NEOPLASTIC CHANGE
 The ischiopubic synchondroses may have irregular mineralization and may be asymmetrically
expanded
 The asymmetry is unusual because most normal variants tend to be symmetric.
 Complete bilateral ossification occurs as early as age 4 years or as late as 14 years
 . Pain and tenderness may be associated with an irregularly mineralized and expanded ischiopubic
synchondrosis, but without positive laboratory findings, further workup is unnecessary.
 A biopsy of this synchondrosis should not be obtained because false-positive results for neoplastic
changes frequently occur.
 Not uncommonly, however, osteomyelitis may involve the ischiopubic synchondrosis, with positive
blood cultures, elevated erythrocyte sedimentation rates, or increased Creactive protein levels
confirming the diagnosis. With adequate antibiotic therapy, the prognosis is good.

12. Osteosclerosis of the Newborn
 A neonate's long bones may appear very dense,
which can be mistaken for pathologic conditions such as osteopetrosis
significant clinical findings are associated with pathologic
osteosclerotic conditions.
 jaundice, hepatosplenomegaly, anemia, and pancytopenia are
associated with osteopetrosis manifesting in the newborn period.
 Normal osteosclerosis of the newborn has no associated signs or
symptoms and resolves several weeks after birth.

13. Physiologic Periosteal New Bone
Formation of the Newborn.
 Physiologic periosteal new bone is not present before 1 month of life
and is most commonly noted between 1 and 6 months of life.
 It is almost always bilateral and symmetric, involving the femur,
humerus, and tibia most frequently.
 The periosteal new bone formation is thin and separated by a lucent
line from the diaphyseal cortex .
 The patient's age, the bilateral symmetry, and the benign radiographic
image differentiate this condition from pathologic entities such as
trauma, congenital syphilis, osteomyelitis, prostaglandin therapy,
infantile cortical hyperostosis (Caffey's disease), leukemia, and
neuroblastoma.

15. Dense Transverse Metaphyseal
Lines.
 Normal children have dense transverse metaphyseal lines, especially between 2 and 6 years of
age,
 that may be confused with radiodense metaphyseal bands associated with lead poisoning
 Two radiographic findings, however, may help to distinguish normal radiodense metaphyseal
lines from those seen in lead poisoning
 : (1) normal dense metaphyseal lines are no denser than the metaphyseal or diaphyseal bony
cortex, whereas the dense metaphyseal bands associated with lead poisoning are usually denser
than the metaphyseal or diaphyseal bony cortex; and
 (2) a dense metaphyseal line commonly involves the proximal fibula with lead poisoning, but
the proximal fibula is usually not involved in the normal patient with dense metaphyseal
lines.[1] Lead poisoning, however, cannot be definitively diagnosed from radiographic findings.
Chemical tests of blood and urine are required to diagnose plumbism

16. Avulsive Cortical Irregularity
 The avulsive cortical
irregularity usually
involves the posterior
aspect of the medial
femoral condyle,
 appearing as an irregular
and concave defect that
may simulate malignancy
 The lesion most probably
results from repetitive
avulsive-type trauma

17. Avulsive Cortical Irregularity
 . This defect is most frequently
seen in 10- to 15-year-olds,
 ismore common in boys, and is
often bilateral.
 An avulsive cortical irregularity
should not be sampled for
biopsy because a misdiagnosis of
osteosarcoma may be made.
 A correct diagnosis is made by
knowing the general age ranges
as well as the characteristic
location and radiographic
features of the avulsive cortical
defect.

18. “leukemia lines”
 It is extremely important
to examine the bones
carefully when leukemia
(most commonly acute
lymphoblastic leukemia)
is considered because
the bone marrow and
peripheral blood smear
may initially be negative,
with only radiographic
changes present.

19. TRUNK
 Rhomboid fossa of the clavicle (N)
 It is an excavation that it is located on the underside of
the sternal end of clavicle where
 the costoclavicular ligament attaches, which serves to
stabilize the sternoclavicular joint.

21. Posterior arch rib fractures
 Posterior arch rib fractures in abused children (P)
 These fractures are often located in the posterior arch,
which follow a straight line. They
 are produced by chest compressions, direct blows and
falls on hard surfaces

23.  Resleor sign (P)
 Bone erosions in the lower edges of the ribs caused by
pressure from
 dilated intercostal arteries in aortic coarctation

25. Limbus vertebrae (N-P)
 The limbus vertebrae originates in childhood and is caused by an
intervertebral disc displacement
causes a separation of a small segment of the vertebral ring from the
rest of the vertebral body, remaining isolated.
The most common location is in the lumbarregion, followed by the
cervical region. This defect is often seen in the supero-anterior margin
 . This anomaly may be confused with a fracture, infection or a tumor
resulting in unnecessary invasive procedures.
It is postulated that the limbus verterbae is a sequel to a previous
unnoticed injury on a immature skeleton
. We must differentiate from a spectrum of disorders such as
osteochondrosis deformans Schmorl nodules
This skeletaldisorder usually causes no symptoms
 treatment is conservative

28. Spondylolysis (P)
 In children, spondylolysis usually occurs between the
fifth lumbar and first sacral
 vertebrae, and is often due to a birth defect in that area
of the spine .
 an slippage of the upper over the lower vertebrae, it
would be a spondylolisthesis

30. Ischiopubic synchondrosis (N)
 The ossification of cartilage located between the ischium
and the pubis is very variable.
 The total bone fusion occurs in only 6% of children 4 years
and 83% of those 12years.
 There may be an expansion and irregular ossification of
this synchondrosis intheprepubertal period.
 The bone fusion usually preceded by an intermittent
increase in size of radiolucent component of cartilage,
which gives it a globular shape
 We must not confuse this entity with other tumors such as
osteomyelitis or eosinophilic granuloma

32. Bone island (enostosis) (N)
 Injuries are often diagnosed as incidental findings.
 They look like lumps in sclerotic cancellous bone of
variable size and irregular surface contours of 2mm to 2cm
in diameter,
 on the bone scan are not active, although there may be
some in the larger ones.
 can occur in any bone, preferably in long bones (femur),
and at any age, but more often after puberty.
 We must not confuse this finding with metastatic
osteosarcoma that may look similar
 the clinical history may guide us toward one or another
diagnosis

34. Femoral epiphyseal growth
retardation (N)
 This entity is also called Meyer dysplasia, although a strict
dysplasia is a defective development of the hip joint the
shape or the organization of the hip joint.
 This delay of ossification of the femoral head, goes
subsequent editing and serial radiographs,
which demonstrate a secondary nucleus ossified and
normal,
 without sequelae or deformities, although there may be
minor changes that do not alter the relationship head -
acetabulum.
 The differential diagnosis must be made with septic
arthritis, Perthes disease, multiple epiphyseal dysplasia and
hypothyroidism

36. Apophysitis
 The term refers to that Osteochondrosis and
apophyseal extra-articular location and have a high
prevalence in children who play sports regularly

37.  Avulsion fractures (P)
 In them there is a commitment to the vertebral bone
and joint. Traction mechanisms
 involved acute tendon or ligament elementsinserted
into the apophysis. There are age
 of onset characteristics. Its severity and treatment
depends on the area affected and the
 degree of displacement

39. Metaphyseal bands (N-P)
 Normal metaphyseal endochondral bone growth (in the
zone of provisional calcification)
 requires the maintenance of a delicate balance between
osteoblastic bone deposition and osteoclastic bone
remodeling .
 Whenever growing bone is subjected to toxic, metabolic,
neoplastic, or infectious stressors, proper osteogenesis is
compromised.
 Stress on growing bone leads to poor endochondral bone
formation.
 In general, when the stress is eliminated, rapid deposition
of new bone at the metaphysis produces dense bands.

40. Metaphyseal bands (N-P)
 They may be sclerotic, usually in relation to growth
stops
 differential diagnosis between different entities such
as: normal newborn, any severe disease, metaphyseal
fracture, leukemia, lymphoma,metastases,congenital
infections, scurvy

42.  Physiological periosteal reaction (N)
 You have to make a differential diagnosis with other causes
of periosteal reaction
 such as child abuse, infections (syphilis), metastatic
neuroblastoma, treatment
 with prostaglandins and Caffey disease. The periosteal new
bone formation
 occurssymmetrically in the bodies of the long bones of
infants and resolves within 3
 months of age. It is believed due to the handling of the
newborn. There are no associated
 fractures (Fig.

43. Distal femoral cortical irregularity
(N)
 This is a normal variant consisting of a periosteal fibrous
proliferation
predilection for the posterior cortex of the distal femoral
medial metaphysis.
 distal femoral metaphyseal defect, cortical desmoid,
irregular or defective cortical avulsion
medial supracondylar femur
The age of onset is between 12 and 20 years and
preferably in males.
Usually resolves spontaneously in the second decade of life.

44. Distal femoral cortical irregularity
(N)
 Radiographically similar to fibrous cortical defect, except as
specific location.
 radiolucent lesion with sclerosis at the base, the cortex
may be irregular and may have spicules that can be
interpreted as a sign of aggression.
 MRI showedhypointensity and hyperintensity on T2-T2,
with a dark rim on both sequences and near the insertion
of the gastrocnemius muscle .
 A bone scan is usually normal. Radiological differential
diagnosis: fibrous cortical defect, periosteal chondroma , #
osteosarcoma.Bone abscess secondary to osteomyelitis

46. Poor radiographic technique (N)
 Sometimes the anomalous position of the pediatric
patient during the acquisition of the
 X-ray can show us false images that can confuse in
establishing a diagnosis
 and

47. Irregularity of the tibial tuberosity
(N)
 The tibial tuberosity is an anterior extension of the
epiphysis of the tibial cartilage.
 It is usually ossified from several sites.
 Ossification usually occurs between 8 and 12 years in
girls and between 9 and 14 in males
 The ossicles can mimic fragments produced by
avulsion. Their appearance is usually not symmetrical.
 The soft tissue edema and thickening of the patellar
tendon in a preteen, suggests the
 diagnosis of Osgood-Schlatter disease

49. Dorsal defect of the patella (N)
 It is a normal variant that should not be confused with
patellar osteochondritis dissecans
 and a clue to differentiate both is that the former does
not produce or produces very little pain and does not
dissect any osteochondral fragments

51. Accessory bones (P) and sesamoid
(N)
 Peroneum Os (N): Os peroneum is an ossicle or
sesamoid bone, oval or rounded located
 in the thickness of the distal peroneus longus tendon
near the cuboid .
 establish a differential diagnosis of fractures ,
nonfused ossification centers or pathologic
calcification of soft tissues

52. Os peroneum

53. Medial cuneiform (left image) and
accesory navicular bone (right
image)

54.  Köhler: Necrosis of the navicular tarsal (P)
 Described by Köhler in 1908 as a navicular self-limiting
disease characterized by flattening, sclerosis and irregular
ossification of this bone.
 has caused more controversy regarding its possible
etiology, some authors label it as a development variant. It
affects children between 3 and 10 years.
 When radiographs are obtained we can find obvious
alterations in the navicular bone
 ossification which appears flattened, with fragmentation
and increased density. In early disease it may keep the
space with neighboring bones, but may suffer a collapse in
its evolution

57. Abused child (P):
 This are quite typical fractures that should be not to be
confused with other normal
 findings such as the proximal radius step

59. Supracondylar humeral process
(N)
 It is a phylogenetic vestige-atavism that can be found
in some people
 corresponds to a asympthomatic normal variant
 to have caused median nerve compression. Differential
diagnosis should be made with osteochondroma

62. DR.RAJEEV