Stryker Hansson Pin System Manual
5
• Slipped Capital Femoral Epiphysis
Operative Technique
Hansson
™
Pin System
Pediatrics
2
Contents
Introduction and Rationale 3
R
elative Indications & Contraindications 4
Features & Benefits 5
Operative Technique
Patient Positioning 6
Reduction 7
Optional Stabilization Guide Wire Insertion 8
Determining the Incision and Insertion Points 9
Skin Incision and Guide Wire Insertion 10
Drilling and Measurement 11
Instrument-to-Pin Assembly 12
Insertion of the Hansson Pin 13
and Activation of the Hook
Instrument Removal 14
Postoperative Regime 15
Pin Removal 16
Ordering Information
Implants 17
Instruments 18
References 19
3
Introduction
The Hansson™ Pin system, designed
by Professor Lars Ingvar Hansson at
the University of Lund in Sweden,
w
as developed based on research
concerning the effects of implants on
the blood supply to the femoral head.
Specifically developed for the
treatment of slipped capital femoral
epiphysis, the Hansson Pin system has
been designed to minimise surgical
trauma to the patient and offer secure,
stable fixation with reduced risk of
healing complications for all grades
of fracture.
Twenty years of successful clinical
studies have been carried out to
enhance the Hansson™ Pin System
to its current form.
This work is summarized in 6 theses
and more than 70 published articles.
Rationale
The methodology involves a cylindrical
pin inserted in a drill hole which
attaches to the femoral head via a hook,
providing strong, stable fixation
through a simple and precise procedure.
The drill hole and pin run at right
angles to the growth zone and are,
depending on the degree of slipping,
r
e
lat
ively centrally located in the
femoral neck and head.
T
he pin is 10-20mm longer than the
dr
il
l hole t
o al
lo
w c
ontinued growth
in the length of the femoral neck.
S
lips of up to 60° can be stabilised
b
y ost
e
osynthesis.
4
Relative Indications & Contraindications
Slipped Capital
Femoral Epiphysis
Adult Femoral Neck Fractures
The physician’s education, training and
professional judgement must be relied
upon to choose the most appropriate
d
e
v
ice and treatment.
Conditions presenting an increased
r
isk of implant failure include:
• Any active or suspected latent
infection or marked local
inflammation in or about the
aff
ected area.
•
C
ompromised vascularity that would
inhibit adequate blood supply to the
fracture or the operative site.
• Bone stock compromised by disease,
inf
e
c
tion or prior implantation that
can not p
r
o
v
ide a
dequate support
and/or fixation of the devices.
•
Material sensitivity, documented
o
r s
usp
ected.
•
O
b
esit
y. An obese patient can
produce loads on the implant that
can lead to failure of the fixation of
the d
e
v
ic
e or to failure of the device
itself.
• Patients having inadequate tissue
coverage over the operative site.
• Implant utilization that would
interfere with anatomical structures
or physiological performance.
•
A
n
y me
ntal or neuromuscular
disorder which would create an
unacceptable risk of fixation failure or
c
o
mplicat
io
ns in postoperative care.
•
O
the
r me
dical o
r surgical conditions
which would preclude the potential
benefit of surgery.
Detailed information is included in the
instructions for use being provided
with each implant.
See package insert for a complete list
o
f
potential adverse effects and
contraindications. The surgeon must
discuss all relevant risks, including the
se
r
vice life of the device and the need
for postoperative protection of the
implant with the child’s parents,
w
hen necessary.
Relative Contraindications
Contraindications
Indications
Due to a lack of any supportive
clinical experience, the Hansson Pin
is not recommended for use with
paediatric hip fractures.
5
Features & Benefits
Preventing diastasis and further
displacement of the epiphysis
The risk of further intraoperative
d
isplacement of the femoral head is
reduced by drilling a channel for the
H
ansson Pin with the femoral head
fixed with kirschner wires. The smooth
outer pin allows the surgeon to gently
push the implant through the channel,
reducing the risk of diastasis between
the femoral neck and the head.
1
Lasting stable fixation
The hook resists loosening of the
fixation to the femoral head as the
longitudinal growth of the femoral
neck retracts the pin in the channel
thereby stabilizing the femoral head.
Loosening of the implant is potentially
reduced because of resorption and
growth of the femoral neck under
normal conditions.
1
Reducing the risk of unequal
bone length
The continued growth of the femoral
n
eck in cases with Slipped Capital
Femoral Epiphysis is an indication
o
f undisturbed intra- and postoperative
vascularization, as the nutrition for the
proliferating cells of the growth plate
is provided by the epiphysial vessels.
By preserving the blood supply,
the Hansson Pin System reduces
the risk of unequal bone length.
1
Easy extraction
The risk of the pin being trapped in
the bone is reduced as the pin surface
is smooth. The hook is easily
withdrawn back into the body of the
pin, which can then be removed.
1
Frontal view
Lateral view
Slipped Capital
Femoral Epiphysis
6
Operative Technique
Step 1 - Patient Positioning
Correct positioning of the patient
on the fracture table is essential for
avoiding problems and complications
d
uring surgery (Fig. 1).
Place the patient in supine position
on the fracture table.
Healthy side: Position the leg on the
healthy side with the hip in flexion
and slight abduction so that the C-arm
can be adjusted intra-operatively for
both the anterior/posterior and the
lateral/medial views. This is necessary to
obtain a true lateral view of the femoral
neck and head (Fig. 2). The purpose of
this view is to avoid the penetration of
the end of the pin through the surface
of the femoral head.
Furthermore, again for avoiding pin
penetration, the surface of the femoral
head must be seen continuously when
moving the C–arm from the horizontal
position to the vertical position.
Slipped side: Position the hip in full
extension with neutral position
between abduction and adduction.
Fig. 1 – Position Patient; C-Arm in A/P View
Fig
.
2 – Position Patient; C-Arm in L/M View