technique

1. Posterior Iliac Crest Bone Graft
Jameel kifayatullah

2. Indications
1. When autogenous grafting is desired that requires a
high ratio of cancellous to cortical bone (a high volume
of osteocompetent cells)
2. Hard tissue maxillofacial defects requiring up to 100
mL of uncompressed bone or 5 cm of structural cortical
graft
3. The presence of a bone void unable to be filled with
local tissue‐grafting techniques
4. The need for augmentation of biologic healing
capability (transfer of osteocompetent cells) to fracture
or osteotomy sites
5. The need for additional osseous structural stability
within traumatic or surgical defects

3. Contraindications
1. Local infection at, or adjacent to, the harvest site
2. Relative: The obese population is at increased
risk for postoperative complications
3. Relative: The smoking population is at increased
risk for postoperative complications
4. Relative: Osteoporotic and osteopenic patients
are more likely to sustain intraoperative or
postoperative fracture at the site of harvest. The
procedure should be approached with caution in
this population

4. Anatomy of the Posterior Ilium
• Osseous structure: The
borders of the posterior
ilium are the iliac crest
superiorly, the posterior
superior iliac spine (PSIS)
posteriorly, and the
greater sciatic notch
inferiorly. The bone is
slightly concave on its
lateral surface with three
distinct ridges comprising
the posterior, anterior,
and inferior gluteal lines

5. Anatomy of the Posterior Ilium

6. Anatomy of the Posterior Ilium
Musculature and fascia:
• The outer surface of the ilium serves
as the broad attachment site for the
gluteus minimus (between the
anterior and inferior lines), the
gluteus medius (between the
anterior and posterior lines), and the
gluteus maximus (from the posterior
line to the iliac crest). The gluteus
medius and minimus comprise the
hip abductors and are innervated by
the superior gluteal nerve. The
gluteus maximus functions to extend
and externally rotate the hip and is
innervated by the inferior gluteal
nerve. The medial edge of the
posterior iliac crest is the attachment
site for the lumbodorsal fascia

7. Anatomy of the Posterior Ilium
• Vasculature:
The superior gluteal vessels
arise from the posterior
division of the internal iliac
system and run adjacent to
the cortex in the superior
aspect of the sciatic notch.
They supply the gluteal
musculature and are
located an average of 63
mm anteroinferiorly from
the PSIS and 37 mm inferior
to a line drawn
perpendicular to the
vertical axis at the level of
the PSIS.

8. Anatomy of the Posterior Ilium
Neurologic structures:
• The superior cluneal nerves originate
from the L1–L3 nerve roots and cross
directly over the posterior iliac crest.
The superior cluneal nerves supply
sensory innervation to the superior
two‐thirds of the buttocks and are
located an average of 68 mm
anterosuperiorly from the PSIS.
• The middle cluneal nerves originate
from the S1–S3 nerve roots and
course from the sacral foramen
laterally. The middle cluneal nerves
supply sensory innervation to the
medial buttock. Excessive traction or
laceration to the superior and/or
middle cluneal nerves can lead to
numbness or symptomatic neuromas.

9. Anatomy of the Posterior Ilium

10. Anatomy of the Posterior Ilium
Neurologic structures
• The greater sciatic notch
contains the following
nerves: the sciatic, superior
and inferior gluteal, internal
pudendal, posterior femoral
cutaneous nerves, the nerve
to quadratus femoris, and
the nerve to obturator
interuns. The greater sciatic
notch is located 6–8 cm
inferior to the posterior iliac
crest and must not be
violated during the surgical
approach to the posterior
ilium

11. Posterior Iliac Crest Bone Graft (PICBG)
Harvesting Technique
Posterior Iliac Approach
1. Harvesting from the posterior iliac region can
be performed with the patient positioned
either prone or in the lateral position. For
harvesting in a prone position, the patient is
intubated supine and then positioned prone,
with 210° of reverse hip flexion.

12. Posterior Iliac Crest Bone Graft (PICBG)
Harvesting Technique
• Anatomical landmarks are
palpated and marked, and
include the posterior iliac
crest, the posterior superior
iliac spine (PSIS), the sacral
midline and the site of the
proposed incision .
• Local anesthetic containing
a vasoconstrictor is injected
at the surgical site. The
patient is prepped and
draped in a sterile fashion.

13. Posterior Iliac Crest Bone Graft (PICBG)
Harvesting Technique
• The patient is
positioned prone with
210° of reverse hip
flexion, and anatomical
landmarks are marked
to include the posterior
iliac crest, the posterior
superior iliac spine, and
the site of the proposed
6–8 cm curvilinear or
oblique skin incision.

14. Posterior Iliac Crest Bone Graft (PICBG)
Harvesting Technique

15. Posterior Iliac Crest Bone Graft (PICBG)
Harvesting Technique
• A 6–8 cm oblique or curvilinear skin
incision originating 3–4 cm lateral to
the midline and 1 cm lateral to the
posterior superior iliac spine is placed
overlying and following the arc of the
palpable bony prominence of the
posterior iliac crest.
• The dissection proceeds through skin
and subcutaneous tissue until the
prominent dorsolumbar (i.e.,
lumbodorsal or thoracolumbar) fascia
is encountered. The dorsolumbar
fascia is transected, and dissection
continues to the posterior iliac crest.
A full‐thickness flap, including the
dorsolumbar fascia, gluteus maximus
muscle, and periosteum, is elevated 1
cm lateral to the PSIS to expose the
outer cortex of the posterior ilium

16. Posterior Iliac Crest Bone Graft (PICBG)
Harvesting Technique
• A full‐thickness flap,
including the
dorsolumbar fascia,
gluteus maximus
muscle, and
periosteum, is elevated
to expose the outer
cortex of the posterior
ilium.

17. Posterior Iliac Crest Bone Graft (PICBG)
Harvesting Technique

18. Posterior Iliac Crest Bone Graft (PICBG)
Harvesting Technique
• Preserving the continuity of this single, stout
layer will greatly facilitate closure of the
surgical site once the graft is obtained and will
minimize postoperative complications.
Preserving the PSIS and its attachments
(sacroiliac ligaments) will minimize
postoperative pelvic instability and will aid in
maintaining a safe distance from the sacroiliac
joint

19. Posterior Iliac Crest Bone Graft (PICBG)
Harvesting Technique
• Subperiosteal elevation continues lateral to
the PSIS and inferior to the posterior iliac crest
for approximately 4–6 cm, depending on the
size of the graft to be harvested. Care is taken
with inferior reflection of the tissues to
minimize damage to the structures within the
sciatic notch and to the superior gluteal
vessels

20. Corticocancellous (Unicortical)
Harvesting
• After exposure of the grafting–
donor site, the osteotomy design
is contrived . The osteotomy size
is dependent on the amount of
bone required by the recipient
site. The medial aspect of the
osteotomy should originate 1 cm
lateral to the PSIS, should extend
no more than 5 cm inferior to the
iliac crest, and should be directed
perpendicular to the crest–iliac
rim to avoid undermining the
PSIS, to orient the medial
osteotomy distal to the sacroiliac
joint, and to reduce the potential
for a future stress fracture of the
posterior ilium.

21. Corticocancellous (Unicortical)
Harvesting
• The osteotomy is
designed 1 cm lateral
(distal) to the posterior
superior iliac spine and
perpendicular to the
iliac crest–iliac rim to
avoid undermining the
sacroiliac joint.

22. Corticocancellous (Unicortical)
Harvesting
The location of the lateral (distal)
osteotomy is placed 4–6 cm lateral
(distal) to the medial osteotomy. The
inferior osteotomy should extend no
more than 5 cm inferior to the
posterior iliac crest–iliac rim. The
superior osteotomy may be designed
to incorporate the iliac rim or may be
performed just inferior to the iliac
rim (a rim‐sparing osteotomy) . The
deep aspect of the osteotomy should
extend just into the marrow cavity.
The osteotomies may be performed
with combinations of chisels and
saws (i.e., reciprocating and
oscillating).

23. Corticocancellous (Unicortical)
Harvesting
• Cancellous bone is
harvested utilizing large
curved and straight
curettes in a
two‐handed, controlled
maneuver, ensuring the
inner table is not
violated

24. Corticocancellous (Unicortical)
Harvesting
• The outer cortical table of
the posterior ilium may be
harvested in strips or as a
whole, depending on the
reconstruction needs of the
recipient site. The outer
cortical table is elevated
with a combination of a
chisel and a freer. Care is
taken to orient the chisel
away from the sacroiliac
joint and sciatic notch–
superior gluteal vessels to
minimize iatrogenic damage
to these key structures

25. Corticocancellous (Unicortical)
Harvesting

26. Corticocancellous (Unicortical)
Harvesting
• Once the outer table has
been removed, cancellous
bone may be harvested
from the underlying
marrow space. Care is taken
to not undermine the PSIS
and to avoid penetration of
the inner table. Cancellous
bone is harvested utilizing
large curved and straight
curettes in a two‐handed,
controlled maneuver,
ensuring the inner table is
not violated.

27. Cancellous‐Only Harvesting: The
Trapdoor Technique
• In this technique, the lateral soft tissue
attachments are not stripped from the ilium.
• After exposure of the grafting site, an incision
is made through the lateral rim of the cortex
of the iliac crest using osteotomies. The crest
is reflected medially, ensuring that all medial
and lateral musculature remains intact

28. Cancellous‐Only Harvesting: The
Trapdoor Technique
• Once exposed, cancellous bone can be curetted
through the “trapdoor,” in which three sides of
the rectangular block are cut and hinged opened
on the fourth side. The harvest should only
extend lateral (distal) to the PSIS, and care should
be taken to avoid perforating the inner table of
the ilium.
• Once the cancellous bone harvest is complete,
the trapdoor is closed and gently secured into
place with a bone tamp

29. closure
• After bone harvesting is complete, all exposed cancellous surfaces are
copiously irrigated and covered with bone wax or Gelfoam to obtain
hemostasis at the graft site and to minimize postoperative hematoma
formation.
• Meticulous hemostasis should be obtained as soft tissues are closed.
Drains are not required if wound hemostasis is achieved.
• Any subperiosteally dissected musculature should be repaired to its origin
on the iliac crest utilizing heavy, absorbable sutures (i.e., 0‐0 Vicryl).
• The wound is closed in a layered fashion. The full‐ thickness deep flap
(dorsolumbar fascia, gluteus maximus muscle, and periosteum) is
reapproximated with 2‐0 Vicryl sutures. The subcuticular layer is closed
with a running 3‐0 Monocryl suture. Skin tension is achieved with surgical
skin glue or steri‐strips with an island dressing overlay.
• Judicious infiltration on local anesthetic both super- ficially and deep will
assist in postoperative pain control.

30. Postoperative Management
• Analgesics should be prescribed as necessary. Non-
steroidal anti‐inflammatory drugs (NSAIDs) should be
avoided as their use may slow the bone‐healing
process.
• Up to 24 hours of prophylactic intravenous antibiotics
may be utilized on an individualized basis.
• The patient can begin weight bearing as tolerated
immediately following surgery.
• The wound should remain sterilely dressed for 5 days
prior to showering. Complete submergence of the
wound should be avoided until the wound is sealed
and healed at about 4 weeks postoperatively

31. Complications
• Donor site pain: Reported to occur in 3–40% of individuals
(highly variable). Pain at the graft site will often decrease
with time, but some individuals develop a persistent
low‐grade pain that may last for months to years.
• Superficial infection: The rate of superficial infection is
similar to that of most orthopedic procedures (ranging from
0.5% to 5%). Superficial infections are treated with or
without antibiotics based on the clinical presentation.
• Deep infection: The rate of deep infection is 1–2.5%. Deep
donor site infections are addressed by surgical irrigation
and debridement with antibiotics as indicated based on the
clinical situation.

32. Complications
• Cluneal nerve injury: May occur if dissection is carried too far laterally
from the PSIS (more than 6 cm). If damaged, the patient may experience
numb- ness, dysesthesias, or chronic neuroma pain in the upper
two‐thirds (superior cluneal) or medial aspect (middle cluneal) of the
buttocks.
• Sacroiliac joint disruption: May occur if bone harvesting is undertaken in
close proximity to the joint or if the joint is undermined with inappropriate
osteotomy design. Disruption of this joint will predispose the patient to
sacroiliac joint pain, instability, and early‐ onset arthritis.
• Abductor weakness: Muscle weakness can occur without appropriate
repair of the lateral muscula- ture dissected free from the ilium. This will
result in a patient with a Trendelenburg gait, which is character- ized by a
drop in the contralateral pelvis during the stance phase of the affected
limb. The patient will com- pensate by leaning their body over the affected
side during the stance phase.

33. Complications
• Major vessel injury: The superior gluteal
vessels run against the cortex of the superior
portion of the greater sciatic notch and can be
injured if aggressive retraction, dissection, or
harvest extends into the notch.
• Major nerve injury: The sciatic and superior
gluteal nerves run within the greater sciatic
notch and can be damaged with errant
violation of this space

34. The posterior iliac region
• The posterior iliac region can provide a large
amount of cortical and cancellous bone graft
(up to 100 mL of uncompressed bone)

35. Mandible defect continuity
reconstruction
• The right posterior
mandible continuity
defect is reconstructed
with two, 2.5 cm × 5 cm
cortical struts.
Additional particulate
grafting was performed
along the medial aspect
of the defect.