Bone is not a uniformly solid material, but
rather has some spaces between its hard
CORTICAL /COMPACT BONE - The hard outer
layer of bones is composed of compact bone
tissue, so-called due to its minimal gaps and
spaces. Its porosity is 5–30%.
- 80% of total bone mass of a skeleton
- consists of haversian canal and osteons
- Filling the interior of the bone is the
trabecular bone tissue
- composed of a network of rod- and plate-
like elements that allow room for blood
vessels and marrow.
- accounts for the remaining 20% of total
- Its porosity is 30–90%
Bone grafting is a surgical procedure that
places new bone or a replacement material
into spaces between or around broken bone
or in holes in bone (defects) to aid in healing.
Used to repair bone fractures that are
extremely complex, pose a significant risk to
the patient or fail to heal properly.
Used to help fusion b/w vertebrae, correct
deformities or provide structural support for
fractures of the spine.
To repair defects in bone caused by
congenital disorders, traumatic injury, or
surgery for bone cancer.
Also used for facial or cranial reconstruction
OSTEOGENESIS - formation of new bone by the
cells contained within the graft.
involves the stimulation of osteoprogenitor cells
to diffr. into osteoblasts that begin new bone
Most widely studied type of osteoinductive cell
mediators in grafts are bone morphogenetic
bone graft material serves as a scaffold for
Osteoblasts from the margin of the defect
utilize the bone graft material as a
framework upon which cells spread and
generate new bone
To promote union as in
- Fresh fractures
- Delayed union
To bridge joints and thereby provide
To bridge major defects or establish the
continuity of a long bone.
To fill cavities/defects
- Infections and other
1)based on the donor origin
2)based on composition
5) based on anatomical features
Bone harvested from the patient’s own body.
Gold standard - sufficient bone of the sort
required is available & at the recipient site,
there is a clean vascular bed.
Iliac crest – commonest site.
1) Cortical bone graft – for filling bone gaps
Tibia mainly, iliac crest & fibula also.
2) Cancellous bone graft – for osteogenic
purpose (eg: non-union).
Thicker portions of the ilium, greater
trochanter, proximal metaphysis of the tibia,
lower radius, olecranon or from an excised
3) Whole bone graft – fibula.
Cancellous grafts become incorporated
more quickly & more completely than
The graft stimulates an inflammatory
response with the formation of a
fibrovascular stroma; through this, blood
vessels & osteoprogenitor cells can pass from
the recipient bone into the graft.
donor site morbidity
Ambulation is delayed until the defect is
pain and infection at the site from which the
graft is taken
Vascularized grafts - sophisticated
microsurgical techniques are necessary & in
major sites of loading , osseous hypertrophy
Muscle-pedicle bone grafting
bone graft is taken along with pedicle of
muscle (with intact blood supply which will
supply blood to graft).
- eg: non-union fracture neck of femur.
Free vascularised grafting – bone (fibula) is
taken along with the vessels supplying it.
- eg:- the iliac crest (complete with one of
the circumflex arteries), the fibula (with the
- Middle 1/3rd of fibula– used as a
vascularised free autograft based on the
peroneal artery and vein pedicle using
microvascular technique - for treatment of
large defects in cong pseudarthrosis of tibia.
Graft obtained from a person other than the
patient (live or dead).
1) small children, where the usual donor sites
don’t provide cortical grafts large enough
to fill a large cavity and when there is
possibility of physeal injury.
2) aged persons
3) patients with poor operative risks
Usually taken from cadavers; it is typically
sourced from a bone bank.
There are three types of bone allograft
1. Fresh or fresh-frozen bone
2. Freeze-dried bone allograft (FDBA)
3. Demineralized freeze-dried bone
Using allograft tissue from another person
eliminates the need for a second operation
to remove autograft bone or tendon.
It also reduces the risk of infection, and
safeguards against temporary pain and loss of
function at or near the secondary site.
Bone variability because it is harvested from
a variety of donors.
Longer time to incorporate with the host
bone and may be less effective than an
Possibility of transferring diseases to the
Potential immune response complications.
Graft obtained from another species.
Xenograft bone substitute has its origin from
a species other than human, such as bovine.
Xenografts are usually only distributed as a
S/E- foreign body reaction.
Material derived from corals
Artificial bone can be created from
ceramic such as calcium phosphates
– porous str. (e.g.hydroxyapatite
and tricalcium phosphate), Bioglass
and calcium sulphate; all of which
are biologically active to different
degrees depending on solubility in
the physiological environment.
Hydroxyapatite is crystalline calcium
phosphate. Slow resorption
made from hydroxylapatite, a naturally
occurring mineral that is also the main
mineral component of bone. They may be
made from bioactive glass.
calcium carbonate - unpopular ;completely
resorbable in short time which make the
bone easy to break again
These materials can be doped with growth
factors, ions such as strontium or mixed with
bone marrow aspirate to increase biological
The presence of elements such as strontium
can result in higher bone mineral density and
enhanced osteoblast proliferation in vivo.
The surgeon does a clinical examination, and
conducts tests to determine the necessity of a
bone graft,to determine the precise location of
damage,exact amount of damage.
These tests include x-rays, MRI, CT scan
Arrange for blood in case a transfusion is needed
Proper nutrition to achieve good nutritional
status before and after surgery.
Single onlay cortical graft: was mainly used for
ununited diaphyseal fractures , used for a
limited group of fresh, malunited and ununited
- bridging joints to produce arthrodesis, for both
fixation and osteogenesis.
Dual onlay grafts: used in treating difficult and
unusual nonunions or for bridging of massive
- eg: for nonunion near a joint
- not as strong as metallic fixatives
- not very osteogenic
- A slot or rectangular defect is created in
the cortex of the host bone.
- occasionally used in arthrodesis particularly
- complex and less efficient
Peg Grafts- for fixation alone
- use limited to non-union of medial
malleolus and small bones of hand ,wrist or
Medullary Graft - poor healing, interferes
with endosteal circulation; rarely used
except in metatarsals, metacarpals and
Osteoperiosteal Grafts- less osteogenic than
multiple cancellous grafts ,and are rarely
Multiple cancellous chip grafts
-widely used, best osteogenic material.
-useful for filling cavities & cysts ,for
establishing bone blocks, and for wedging in
-Soft and friable.
Hemicylindrical grafts- for obliterating large
defects in tibia and femur.
- massive hemicylindrical cortical graft from
affected bone is placed across the defect and
is supplemented by cancellous bone.
Tourniquet to be applied.
Make a slightly curved longitudinal incision
over AM aspect of tibia
Incise and reflect the periosteum
Drill a hole at each corner of the anticipated
Remove the graft by cutting through the
cortex at an oblique angle.
Remove cancellous bone from the proximal
end of tibia with a curet.
- normal limb is jeopardised
- Convalescence is prolonged
- Tibia more prone for fractures for 6-12
3 points to be considered:-
-peroneal nerve must not be damaged.
-distal 1/4th of the bone must be left to
maintain a stable ankle.
-do not cut peroneal muscles.
Resect the middle 1/3rd
Dissect along the anterior surface of septum
b/w peroneus longus and soleus.
Reflect peroneal muscles anteriorly.
Start stripping till fibula exposed.
Drill holes through fibula at the anticipated
area of graft.
acquired bowel herniation (this becomes a
risk for larger donor sites (>4 cm)).
meralgia paresthetica (injury to the lateral
femoral cutaneous nerve also called
fracture (extremely rare and usually with
injury to the ilioinguinal nerve
minor hematoma (a common occurrence)
deep hematoma requiring surgical
pseudoaneurysm of iliac artery (rare)
To efficiently provide safe and useful
Uses thorough donor screening,rapid
procurement, and safe sterile processing.
Donor screening for bacterial,viral and
C/I- malignancy( except BCC), collagen
vascular diseases,metabolic bone dissease
and presence of toxins.
Bone can be harvested in a clean nonsterile
environment, sterilised by irradiation,strong
acid or ethylene oxide , and then freeze
dried for storage.
Bone under sterile conditions , can be deep
frozen (70-80 deg) for storage.
Fresh frozen bone is stronger than freeze-
Cancellous bone can be obtained in a
New BMP products are expected to be strong
inducers of bone growth (osteoinductive).
These new products will be relatively
expensive, but will grow bone better than
the patient's own bone, eliminating the need
for bone graft harvesting.
The INFUSE Bone Graft (rhBMP-2, BMP 7) has