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Key Techniques in Orthopaedic Surgery

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ening of the frame in the follow-up period.
What To Avoid
1. Do not place the pins percutaneously. This may
increase the risk of cutaneous sensory nerve injury.
2. Do not leave the wrist in over-distraction as this will
greatly increase the potential for finger stiffness and
delayed union.
3. Avoid excessive ulnar deviation and/or flexion. If
such positioning is necessary to maintain align-
ment, supplemental fixation should be considered.
4. Avoid tight closure of the skin around the pins as
this will lead to skin irritation.
5. Avoid tethering tendons and muscles with the pins.
Postoperative Care Issues
1. A light compressive dressing is applied around the
pin sites and is changed at the first follow-up visit.
2. Overnight hospitalization for observation may be
indicated.
3. Immediate finger motion is emphasized and assis-
tance from an occupational therapist may be help-
ful in the early postoperative period.
4. Do not neglect range of motion activities for the
forearm, elbow, and shoulder.
5. Remove stitches after 10 days.
6. Obtain follow-up radiographs at 1, 3, and 6 weeks.
7. The timing of fixator removal is controversial.
Generally, the fixator is kept in place for approxi-
mately 6 weeks. Earlier removal can occur in the set-
ting of bone grafting and/or supplemental fixation.
Operative Technique
1. With the patient supine, ensure good access to the
dorsal-radial aspect of the wrist.
2. The extremity is prepared and draped free in the
usual sterile fashion. The planned incision sites are
shaved.
3. The primary surgeon is seated at the patient’s axilla.
The fluoroscopy unit is positioned for easy access to
the surgical field, either at the end of the hand table
extension or opposite the primary surgeon.
4. First perform a closed reduction maneuver, then
proceed with frame application; 10 to 12 pounds of
finger-trap traction can be helpful.
5. The tourniquet should be inflated prior to pin
placement.
6. Pins should be oriented 35 to 45 degrees from the
frontal plane to avoid interference with thumb
motion. Constructing the frame at this angle will
also permit unobstructed lateral radiographs of the
distal radius.
7. Distal pin placement is performed through either
two stab incisions or a single longitudinal incision
(Figs. 16–1A and 1B).
1 6 D I S TA L R A D I U S F R A C T U R E S ( E X T E R N A L F I X AT I O N ) 9 9
a. When dissecting down to the bone, care should
be taken to avoid damage to dorsal veins and
branches of the radial sensory nerve.
b. Visualize the central portion of the index
metacarpal to facilitate sound bicortical pur-
chase during pin placement.
c. Pin guides included with the external fixator sys-
tem are generally used to assist in pre-drilling
and pin placement.
d. The AO/ASIF system allows for metacarpal pins
to be placed at a converging angle to maximize
bone purchase (a converging angle of 40 to 
60 degrees is recommended). Many newer fixa-
tor systems necessitate pin placement perpendi-
cular to the metacarpal shaft.
e. The more proximal of the 2 pins can also be
engaged into the radial cortex of the third
metacarpal for additional purchase strength.
This will often require placement of all fixator
pins in line with the frontal plane.
f. Avoid tethering the first dorsal interosseous
muscle when placing pins.
8. Proximal pin placement is generally in the middle
to distal portion of the radius.
a. The proximal pins should be oriented in the
same plane as the distal pins (35 to 45 degrees
from the frontal plane).
b. An open approach is recommended as blind pin
placement risks injury to the radial sensory
nerve and branches of the lateral antebrachial
cutaneous nerve. The incision is generally 4 to
5 cm in length, centered at the junction of the
middle and distal one-thirds of the radius.
c. The interval between the extensor carpi radialis
longus and extensor carpi radialis brevis tendons
is identified and developed. The abductor polli-
cis longus and the extensor pollicis brevis ten-
dons are frequently visualized at the distal end
of the incision (Fig. 16–2).
d. The dorsal and volar margins of the radial shaft
should be exposed to ensure central placement
of the pins.
e. Templates or guides can be used to facilitate pre-
drilling and pin placement.
9. Verify bicortical fixation of all 4 fixator pins with
fluoroscopy.
10. Irrigate the wounds and close the skin edges loosely
with interrupted sutures.
11. Deflate the tourniquet.
12. Assemble the fixator frame onto the pins, taking
into account radiographic accessibility to the frac-
ture site.
13. Before tightening the fixator, make final adjust-
ments to the fracture reduction.
a. At this stage, K-wires can be used as joysticks for
fracture manipulation and also as supplemental
fixation.
b. Fine tuning of fracture alignment is possible
with most fixator systems.
c. The ideal position of the wrist is neutral flex-
ion/extension and radial/ulnar deviation. If
excessive flexion or ulnar deviation is required
to maintain fracture alignment, supplemental
fixation is recommended (Fig. 16–3).
d. Check the carpus under fluoroscopy for over-dis-
traction. The radiocarpal interval should be no
more than 1 to 2 mm wider than the midcarpal
interval on the AP projection. The carpal height
index (CHI) can also be helpful in determining
over-distraction. Caution is advised in over-
reliance upon radiographic parameters, how-
ever, as recent investigators have questioned
their reliability.
e. Make sure that the fingers can be easily flexed to
a complete fist as an additional check against
over-distraction.
14. If K-wires have been placed, the exposed tips are
either bent or capped.
15. Check the skin around the pins for excessive ten-
sion and make relaxing skin incisions as necessary.
16. A light compressive dressing is applied and the
patient is transferred to the recovery room once
stable.
17. A postoperative sling can be used for comfort.
Instructions are given to begin early finger motion
and to elevate and ice the wrist to reduce postoper-
ative swelling.
1 0 0 W R I S T A N D H A N D
1 0 1
Extensor digitorum communis
Extensor indicis proprius
Index extensors retracted
First dorsal 
interosseous muscle
Superficial branch of
radial nerve
Frontal plane
Metacarpal 2
A
B
Figure 16–1 (A) Distal pin placement. Distal pin placement is
performed through either two stab incisions or a single longitudinal
incision. When dissecting down to the bone, care should be taken 
to avoid damage to dorsal veins and branches of the radial sensory
nerve. (B) Distal pin placement. Seat the pins at a converging angle 
of 40 to 60 degrees to maximize metacarpal bone purchase. Orient
both pins 35 to 45 degrees from the frontal plane to avoid interference
with thumb motion.
1 0 2
Second and third metacarpal bones
Tendons of extensor carpi radialis longus, brevis muscles
Adductor pollicis longus muscle
Extensor pollicis brevis muscle
Extensor carpi radialis brevis muscle
Extensor carpi radialis 
longus muscle
Supplemental K-wire fixation at distal radius
Figure 16–2 Proximal pin placement. For the
proximal pins, the incision is generally 4 to 5 cm
in length, centered at the junction of the middle
and distal one-third of the radius. The interval
between the extensor carpi radialis longus 
and extensor carpi radialis brevis tendons is
identified and developed. The abductor pollicis
longus and the extensor pollicis brevis tendons
are frequently visualized at the distal end of the
incision. The dorsal and volar margins of the
radial shaft should be exposed to ensure central
placement of the pins.
Figure 16–3 External fixator placement. The ideal position of the wrist
is neutral flexion/extension and radial/ulnar deviation.