Bone growth occurs through two mechanisms: endochondral ossification and intramembranous ossification. Physeal injuries represent 15-30% of fractures in children and commonly involve the phalanges, wrist, and distal tibia. Physeal fractures are classified using the Salter-Harris system from Type I to V based on the location of the fracture line and potential for growth disturbance. Types I-III involve the physis while Types IV-V cross into the epiphysis, increasing the risk of growth arrest or deformity. Proper classification guides treatment to restore anatomy and minimize long term sequelae.
Bone growth isachieved by adding
newly synthesized bone to existing
bone by two mechanisms:
Endochondral ossification
Intramembranous ossification
Bone growth
3.
bone formsvia a cartilaginous intermediate
physis best reflects this process
From 9 to 10 weeks' gestational age to skeletal
maturity at 15 to 17 years, they are responsible for
the longitudinal growth of bone
Endochondral
ossification
4.
Physeal injuriesrepresent 15% to 30% of all fractures
in children.
The incidence varies with age and has been reported
to peak in adolescents.
Physeal injuries involving the phalanges account for
over 30% of all physeal fractures (wrist jt more
common)
5.
Growth hormone increasesthe number of cells in
the physeal columns;
Thyroid hormone potentiates cytoplasmic
proliferation;
Oestrogens play an important role in triggering
physeal closure.
Hormonal effects upon
skeletal growth
Epiphyaseal vessels—supplygerminal layer
Metaphyseal vessels—supply central ¾ of physis
Periosteal physis—supply peripheral
Types of epiphysis
Pressure epiphysis
Traction
Atavistic
aberrant
Blood supply of physis
10.
The firsttwo zones have an abundant extracellular matrix
and, consequently, a great deal of mechanical integrity,
particularly in response to shear forces.
The third layer, the hypertrophic zone, contains scant
extracellular matrix and is weaker. On the metaphyseal side
of the hypertrophic zone there is an area of provisional
calcification leading to the zone of enchondral ossification.
The calcification in these areas provides additional
resistance to shear.
Thus, the area of the hypertrophic zone just above the area
of provisional calcification is the weakest area of the physis,
and it is here that most injuries to the physis occur
11.
It isa wedge-shaped group of germinal cells that is
continuous with the physis
The zone of Ranvier consists of three cell types—
Osteoblasts form the bony portion of the perichondral ring
at the metaphysis;
chondrocytes contribute to latitudinal growth;
fibroblasts circumscribe the zone and anchor it to
perichondrium above and below the growth plate.
Zone of Ranvier
12.
It isa fibrous structure that is continuous with the
fibroblasts of the zone of Ranvier and the periosteum
of the metaphysis.
It provides strong mechanical support for the bone–
cartilage junction of the growth plate
Perichondrial Ring
(LaCroix)
Epiphyseal blood supply
byDale and Harris
Type A,
The epiphysis is nearly entirely covered by
articular cartilage.
Consequently, the blood supply traverses the
metaphysis and may be damaged on
separation of the metaphysis and epiphysis.
Type B,
The epiphysis is only partially covered by
articular cartilage.
Because the blood supply enters through the
epiphysis, separation of the metaphysis and
epiphysis will not compromise the blood
supply to the germinal layer
Proximal femur
Proximal
humerus
Distal femur
Proximal & distal
tibia
Distal radius
15.
The mostfrequent mechanism of injury is fracture
M C, fracture injury is direct, with the fracture pattern
involving the physis itself. Occasionally, physeal injury from
trauma is indirect and associated with a fracture elsewhere in
the limb segment, either as a result of ischemia or perhaps
compression
infection, disruption by tumour, cysts, tumour-like disorders,
vascular insult, repetitive stress, irradiation, and other rare
etiologies
Etiology
16.
Long boneosteomyelitis or septic arthritis
(particularly of theshoulder, hip, and knee) can cause
physeal damage resulting in either physeal growth
disturbance or frank growth arrest
17.
Partial orcomplete growth arrests can occur from a
pure vascular injury to an extremity.
Salter–Harris type V injuries; the most common
location for this is the tibial tubercle after femoral
shaft or distal femoral physeal fractures
Vascular Insult
18.
EPIDEMIOLOGY
SH2 MC
PHALNGES 44%, DISTAL RADIUS 18%,DISTAL
TIBIA11%
MALE:FEMALE -2:1- 14YEARS:12YEARS
occurred twice as often in the upper extremities as
in the lower extremities.
19.
Salter and harris
Based on the Radiographic appearance of fracture.
The first three types were adopted from Poland
(types I, II, and III) and Aitken (Aitken type III
became Salter-Harris type IV)
The higher the classification the more likely Is
physeal arrest or joint incongurity to occur
20.
Is aseparation of the epiphysis from
the metaphysis occurring entirely
through the physis. It usually occurs
in the zone of hypertrophy (weakest)
It is rare and seen most frequently in
infants or in pathologic fractures, such
as those secondary to rickets or
scurvy.
Because the germinal layer remains
with the epiphysis, growth is not
disturbed unless the blood supply is
interrupted, as frequently occurs with
traumatic separation of the proximal
femoral epiphysis.
Phalenges
Metacarpals
21.
Radiographs ofundisplaced type I physeal fractures, are
normal except for associated soft tissue swelling.
type I fractures occurred most frequently in the phalanges,
metacarpals, distal tibia, and distal ulna.
Epiphyseal separations in infants occur most commonlyin the
proximal humerus, distal humerus, and proximal femur
Ultrasound is particularly helpful for assessing epiphyseal
separations in infants (especially in the proximal femur and
elbow regions) without the need for sedation
22.
The fracture extendsalong the
hypertrophic zone of the physis and at
some point exits through the metaphysis.
The epiphyseal fragment contains the entire
germinal layer as well as a metaphyseal
fragment of varying size. This fragment is
known as Thurston Holland's sign.
The periosteum on the side of the
metaphyseal fragment is intact and
provides stability once the fracture is
reduced. Growth disturbance is rare
because the germinal layer remains intact.
distal radius
23.
By def:- theycross the germinal layer and
are usually intra-articular.
Often ass with high-energy or
compression mechanisms of injury, which
imply greater potential disruption of the
physis & higher risk of subsequent growth
disturbance
Consequently, if displaced, they require
an anatomic reduction, which may need to
be achieved open
Tillaux #
distal
humerus
24.
Salter–Harris typeIII fractures begin in the epiphysis
as a fracture through the articular surface and extend
vertically toward the physis. The fracture then courses
peripherally through the physis.
The articular surface is involved and the fracture line
involves the germinal and proliferative layers of the
physis.
25.
Vertical shear #Extend from the metaphysis
across the physis and into the epiphysis.
Thus, the # crosses the germinal layer of
the physis and usually extends into the
joint. (articular)
This # pattern is frequent around the medial malleolus, Lateral condylar
fractures of the distal humerus (milch type 1) and intra-articular two-part
triplane fractures of the distal tibia
with displacement, may result in metaphyseal–epiphyseal
cross union there by causing growh disurbance
treatment principles include obtaining anatomic reduction and adequate
stabilization to restore the articular surface and prevent metaphyseal–
epiphyseal cross union
26.
Is a crushinginjury to the physis from a
pure compression force.
Those authors who have reported type V
injuries have noted a poor prognosis, with
almost universal growth disturbance
Eg:- Of such an injury is closure of the
tibial tubercle, often with the development
of recurvatum deformity of the proximal
tibia, after fractures of the femur or distal
femoral epiphysis
unrecognized on initial radiographs.
Undoubtedly, more sophisticated imaging of
injured extremities (such as with MRI) will
identify physeal injuries in the presence of normal
plain radiographs
27.
Injury tothe perichondrial ring
Type 6 injury RANG
28.
Trauma toepiphysis (chondral to osteochondral)
Isolated injury of the epiphyseal plate
Type 7 ogden
29.
# ofmetaphysis
Isolated injury of the metaphysis with possible
impairement of enchondral ossification
Type 8
30.
Avulsion injuryto periosteum
which may impair intramembranous ossification
Type 9
Type Iis a fracture of the metaphysis extending to
the physis. Types II to V are the equivalents of Salter-
Harris types I, II, III, and IV, respectively. Peterson
type VI is epiphyseal (and usually articular surface)
loss. Lawnmower injuries are a frequent mechanism
for type VI injuries
Displaced Salter-Harris IVfracture of the proximal tibia
The lateral portion of the epiphysis and the medial
portion of the epiphysis are independently displaced
41.
initial injury radiographof ankle subjected to significant
compressive and inversion forces. minimally displaced
fractures of tibia and fibula with apparent maintenance
of distal tibial physeal architecture.
42.
Follow-up radiograph -growth arrest secondary to Salter-
Harris V injury. Note the markedly asymmetric Park-
Harris growth recovery line, indicating that the lateral
portion of the growth plate continues to function and the
medial portion does not.
43.
Mortise radiograph -TheSalter-Harris VI pattern. In this
case, the radiograph indicates that it is quite likely that a
small portion of the peripheral medial physis (as well as
a small amount of adjacent epiphyseal and metaphyseal
bone) has been avulsed
Xray ofthe injured limb in atleast 2 views
Classification of injury types usually done by
radiograph
Ct scans may clarify complex # patterns
Mri may show considerably more physeal damage
Generally all type1 and type 2 # do well
with closed reduction
All type 3 &4 # should be treated by ORIF
regardless of the amount of displacement
In type V fractures, the cartilage cells of the physis are crushed,
and regardless of the form of treatment, growth disturbance can
occur.
A type V fracture usually is diagnosed only in retrospect when a
growth disturbance develops
48.
General principles ofRx
Most SH I and II injuries can be treated with closed
reduction and casting or splinting and then
reexamination in 7-10 days to evaluate maintenance
of the reduction.
Displaced injuries:- require reduction (within 48
hours) because growth arrest is common after late
reduction.
49.
Greater angular deformitycan be tolerated in the
upper extremity than in the lower extremity,
More valgus deformity can be tolerated than varus,
More flexion deformity can be tolerated than
extension.
50.
More proximaldeformities of the lower extremity (in
the hip) are better compensated for than distal
deformities (the knee and, least of all, the ankle).
Spontaneous correction of angular deformities is
greatest when the asymmetry is in the plane of flexion
or extension (ie, the plane of joint motion),
Function often returns to normal unless the fracture
occurs near the end of growth.
51.
younger the patient,:-more remodeling
potential, greater degrees of displacement are
acceptable. But have greater potential for
deformity.
A growth plate that requires higher energy to
cause failure tends to have a higher rate of
growth arrest. For instance, the distal femoral
and proximal tibial
52.
(SH IIIand IV)-require ORIF.
Smooth pins should parallel physis in epiphysis or metaphysis,
avoid physis.
Oblique application of pins across physis considered only
when satisfactory internal fixation is unattainable with
transverse fixation.
Type V fractures - rarely diagnosed acutely, treatment often
delayed until formation of a bony bar across physis.
A high level of clinical suspicion is necessary
Crossing thephysis with any form of fixation should
be avoided if possible
In type III and IV fractures the pins should cross the
epiphysis in the fractured areas
In type II and IV fractures they should cross the
metaphysis and epiphysis rather than the physis if
possible.
Small cannulated screws are well suited for these
fractures.
55.
COMPLICATIONS
1)Growth acceleration
first 6-18months after injury.
increased vascular response.
use of fixation devices that may stimulate
longitudinal growth.
Treatment in adolescents may involve an
epiphysiodesis.
If more than 6 cm of correction is desired-
lengthening procedures for bilateral limb-length
equilibration.
56.
2) Growth arrest
Premature partial growth arrest is far more common and
can appear as peripheral or central closures. Complete
growth arrest is uncommon.
angular deformities and limb-length discrepancies.
Peripheral arrests are produced when (bone bar/bridge)
forms, connecting metaphysis to epiphysis, traversing the
physis. If bar is located medially, the normal physis
continues to grow laterally, producing a varus deformity.
Anterior bone bars - recurvatum deformity.
57.
Central growtharrests - tented lesions of physis and
epiphysis due to a central osseous tether with metaphysis,
resulting in physeal coning.
Some longitudinal growth continues in patients with
growth retardation, though at a much slower rate; thus, a
progressive shortening of the limb occurs.
Partial growth arrests may be visible on radiographs as
early as 3-4 months postinjury or may be delayed as long
as 18-24 months.
Follow-up checks may be necessary for 1-2 years
postinjury to monitor physeal healing and growth
response.