what-when-how
In Depth Tutorials and Information
on these records, indications and outcomes of each
case were compared and adverse outcomes identified,
and the effectiveness and safety of the applied surgi-
cal techniques was evaluated. Notes were reviewed
from the preoperative evaluations through the post-
operative follow-up clinical visits. Patients' cases were
reviewed for preoperative deformities, pre- and post-
operative functional capacity, types of surgical inter-
vention, postoperative course of healing, immediate
and long-term outcomes, and adverse outcomes and
complications.
Stabilization of Non-Unions
In 16 procedures on 12 patients, healing of non-
union due to a previous fracture or osteotomy was
a primary indication. Thirteen procedures were
done to repair a fracture, including four acute frac-
tures and nine fractures which had developed into
chronic non-unions over the course of months or
years. Three surgeries were performed to stabilize
non-unions of osteotomies from previous procedures.
In 14 cases, the non-unions and fractures were stabi-
lized with internal fixation and 12 non-unions were
treated with strut or “sandwich” allografts, including
ten treated with strut allografts supplemented with
additional implant.
The use of strut allografts and metal fixation proved
to be an effective approach to stabilization in the cases
reviewed. In 15 of 16 cases, evidence of healing was
seen within the timeframe of follow-up, with one case
complicated by additional trauma during the follow-
up period. Thirteen showed early evidence of bone
healing, including callus formation and periosteal
bridging, within the first 4 months following surgery.
Incorporation of strut allografts generally took lon-
ger than healing of fracture or osteotomy in the native
bone. In all cases with a follow-up period longer than 6
months, good incorporation of allografts was seen in 6
to 24 months. There was no clear difference in the post-
operative healing course between groups of cases uti-
lizing different methods of stabilization (strut allograft,
metal fixation or both). However, this may be due to the
fact that the appropriate method of stabilization was
selected based on the demands of each case, resulting in
adequate stability in each case.
The treatment of a chronic non-union of a humerus
fracture by allograft is shown in
Figure 48.2
. The frac-
ture occurred 8 years prior, and multiple attempts had
been previously made to treat it, including intramedul-
lary rodding and bone morphogenic protein placement.
However, these treatments were unsuccessful and there
was significant resorption of bone, resulting in axial
and rotational instability as well as loss-of-function
of the arm. Anatomic alignment of the humerus was
restored using a Foresight nail pinned proximally and
interlocked distally. The non-union site was then stabi-
lized with two pieces of allograft radius, sandwiched
around the native bone and held in compression with
cerclage wires and Songer cables, providing rotational
stability. Allograft cancellous cubes were placed in the
spaces between the two pieces as well. On follow-up,
there was evidence of callus formation at the allograft
site at 6 months and the allograft was incorporat-
ing distally at 1 year. The patient gained strength
and improved range of motion in the arm, with the
humerus moving as one unit.
SURGICAL OUTCOMES
Correction of Limb Deformities
In all patients with limb deformities, an immedi-
ate improvement in alignment was achieved following
the procedures and the alignment remained consis-
tently improved in 13 of 14 cases during several months
of postoperative follow-up. When allografts were
used, they effectively provided stability at the oste-
otomy sites, particularly improving rotational stabil-
ity. Adverse outcomes, discussed in more detail below,
included the development of prominent intramedullary
(IM) rods in two cases due to the shortening of femora
following osteotomies and chronic non-unions of tibial
osteotomies requiring additional procedures to achieve
stability.
Figure 48.1
shows pre- and postoperative images
from the correction of a representative tibial valgus
deformity. The patient had mild distal antecurvatum
and valgus of the right tibia, resulting in misalign-
ment in the right ankle causing pain and instability
on ambulation. An anteromedial wedge osteotomy
was made in the tibia and a Rush rod was inserted
into the intramedullary canal to bring the tibia into
correct alignment. The osteotomy site was stabi-
lized against rotational motion with an 8 cm piece of
femoral allograft applied to the lateral aspect of the
tibia, contoured to minimize additional prominence
and held in place with six screws, three proximally
and three distal to the osteotomy. Based on imaging
studies from follow-up clinical visits, the allograft
showed early signs of bone bridging at 5 months, the
osteotomy site was nearly obliterated at 9 months
and the allograft showed excellent incorporation by
15 months postoperatively. Functionally, the patient
developed a full range of motion, normal strength
and improved stability in the lower right extremity.
The preoperative pain from bowing and instability
was relieved, although there was some residual ten-
derness on medial aspect of the tibia, where allograft
was not placed (
Figure 48.1
).
