Efficacy of Allogenic Bone Graft Per Se and when Augmented with Various Adjuvants in Fracture Healing
Lakhwani OP1*, Jindal M2*, Agarwal S1 and Garg Keerty3
1Department of Orthopaedics, ESI – PGIMSR, India
2Department of Orthopaedics, Kalpana Chawla Govt Medical College, India
3Department of Anaesthesia, Guru Nanak Medical College, India
Submission: March 28, 2018;Published: May 04, 2018
*Corresponding author: Jindal M, Department of Orthopaedics, Assistant Professor, Kalpana Chawla Govt Medical College, Karnal, Haryana, India, Tel: +91-9891904545; Email: email@example.com
How to cite this article: Lakhwani OP, Jindal M, Agarwal S, Garg K. Efficacy of Allogenic Bone Graft Per Se and when Augmented with Various Adjuvants in Fracture Healing. Ortho & Rheum Open Access J 2018; 11(4): 555820. DOI: 10.19080/OROAJ.2018.11.555820.
Introduction: Bone grafts are often required in current orthopedic practice. Limited availability and donor site morbidity associated with the use of autograft has lead to the use of allogenic bone graft. However use of allografts may carry a potential risk of infection and disease transmission and has less osteogenic potential compared to autografts. Hence use of adjuvants such as autologous bone marrow and bone graft along with allogenic bone is required and formed the basis of this study.
Materials and Methods: Study involved case series of eighteen patients with difficult fracture and established delayed & non union treated with allogenic bone graft alone or with adjuvants (bone marrow and or autograft). Outcome was assessed in terms of fracture healing, infection and osteointegration.
Results: over all 15 fractures (83%) united. None of the patient developed infection. Three cases, of which two where allogenic bone graft was used alone and one in which allograft augmented with autologous bone marrow was used, failed to unite and bone graft was absorbed gradually.
Conclusion: Allogenic bone can serve as excellent material for prophylactic or primary bone grafting in difficult to heal fractures as it potentiates bone healing and bridges bone gaps. However in established cases of delayed and non unions which require grafts with good osteogenic potential, use of allogenic grafts along with adjuvants like bone marrow and autologous bone graft is more beneficial.
Level of Evidence: level IV.
Keywords: Allogenic bone graft; Fracture healing; Non union; Difficult fracture
Bone grafts1 are often necessary to potentiate the bone
healing in cases of fractures having communition, bone loss,
delayed union, non unions and other difficult to heal fractures
[1,2]. Autologous bone grafts are the gold standard [3,4] due to
their higher osteoinductive potential as compared to allografts
and no risk of immunogenic reaction and disease transmission
[3-5]. But autologous bone grafts have restrictions of limited
availability and donor site morbidity [5,6] Allogenic bone
grafts, on the other hand, are available in sufficient quantities
and without any risk of donor site morbidity [5,6]. but their
effectiveness in fracture healing is still debatable [6-8]. Present
case series describe the use of allogenic bone graft alone and
combined with adjuvants like autologous bone graft and/or
autologous bone marrow (Figure 1). Improved technique of
Gamma sterilization and prophylactic vancomycin impregnation
were also used to take care of allograft associated infection
[9,10]. Results were assessed in terms of fracture healing,
osteointegartion and infection.
The study was approved by institutional ethical committee
of ESI-PGIMSR, Basaidarapur, New Delhi and all patients were
fully informed and agreed to participate in the study. The
inclusion criteria were patients with difficult to heal fracture
such as comminuted fractures, fractures with bone defects/
bone loss, delayed union and non unions. Exclusion criteria
were active osteoarticular infection at the concerned site. From
2011 to 2013 eighteen consecutive cases of selected fractures
were treated with allogenic bone grafting with appropriate
surgical procedure for fixation wherever required. Out of
eighteen cases, nine cases were of established non-unions, four
cases were of delayed union and rest five cases belonged to
difficult fracture category, that is, relatively fresh fractures with
severe communition and bone loss. In study among 18 patients,
allogenic bone graft augmented with autologous bone graft
was used in nine patients (n1=9), autologous bone marrow in
five (n2=5) and allograft alone in four (n3=4).The case series
consisted of fifteen male patients and three female patients with
a mean age of 35 years (16-68 years) and a mean follow-up of 12
months (8 months- 17 months).
Allogenic bone grafts procured from consenting patients
having undergone hip and knee arthroplasty at institutional
bone bank. Allografts were stored at -80°C for minimum of three
months before use. The terminal Sterilization was achieved by
giving a dose of 25 K grays of radiation at an accredited centre.
The graft was manually morcelized to fragment size of 0.4-
0.6cms and washed with plenty of sterile saline. The bacterial
cultures of the allograft were taken before implantation to
ascertain sterility and were all negative. Morcellized bone grafts
were impregnated with solution of vancomycin 50mg/ml as
described by Witso et al.  for a period of one hour.
Patients were seen at 3rd wound check, then 2 weeks
postoperatively for suture removal and again at 6 and 12
weeks. Particular attention was given to any sign of infection/
inflammation. Radiographs were done every four weeks for initial
four months and then at every two months till completion of
follow up. Radiographs were used to qualitatively determine the
status of union which was defined as presence of at least three of
four healed cortices and crossing trabeculae on anteroposterior
and lateral radiographs while clinical healing was defined as the
absence of functional pain and local tenderness at fracture site.
Rate of osteointegration of allograft was assessed using criteria
given by Sloof et al.  (Table 1) and infection as per clinical,
haematological and biochemistry test according to the Surgical
Site Infection (SSI) guidelines.
Radiographic evaluation demonstrated osseous union
following the index surgery in 15 out of the 18 cases (83%).
Time duration to achieve adequate union in nine cases where
auto graft was used as adjuvant was 8±0.76 months compared to
bone marrow aspirate 9±0.49 months and in one allograft alone
case was 8.5 months. Three failure cases comprised of two cases
where allograft alone were used and one case allograft with
bone marrow. In all case of fracture union gradual and partial
osteointegration was achieved comparing quantity of graft used
in serial skiagram. In three cases of failure allogenic bone graft
was gradually and completely reabsorbed by 4-5 months. None of the
patients developed infection at the surgical site following
the operative procedure during follow up period.
The efficacy of autologous bone grafting in augmentation of
fracture healing is well proven and also no risk of transmission
of occult disease or infection. Various studies have reported
varied success with allogenic bone graft. Hierholzer et al. 
reported an overall union rate of 100% with use of allogenic
bone graft for fracture non unions. Michael A Flierl et al. 
compared the use of autogenic and allogenic bone graft showed
that the cases with autograft took less time to union (198±172–
225 days) as compared to allograft (416±290–543 days) and the
overall postoperative infection rate was significantly lower in
the autograft group (12.4%), compared to the allograft cohort
Present case series showed allogenic bone grafts can be
made more effective by adding osteogenic potentiators such as
autogenic bone graft and or autologous bone marrow. In our
series out of total 18 patients, 4 cases were of delayed union, 9
cases of frank non-union and 5 cases of difficult fractures which
had relatively fresh fractures with severe communition and
bone loss. Of these 5 cases of difficult fractures, 1 case was open
grade II and 2 cases were open grade IIIb. So the biology and
soft tissue envelope was not preserved in these cases and there
was significant bone loss which required primary bone grafting.
Difficult fractures in which primary bone grafting was done took
an average time of 7.2 months to unite; the delayed unions took
an average time of 8 months to unite while the non unions took a
maximum of 12.6 months on an average to unite. Thus relatively
older fractures such as in cases of delayed unions and non unions
do take a longer time to heal. This appears to signify the need of
some osteogenic potentiator along with the allogenic bone graft.
These findings are comparable with works of Kong Z et al. 
who used a combination of bone allograft with autologous red
marrow with appropriate internal fixation and reported union
rate of 91% and average time of union of around 4 months for
fresh fractures and 6 months for old fractures in their series of
38 patients with varied types of fractures with bone loss (Figure
2). Hierholzer et al.  reported an average union time of 4.2
months in case of use of allogenic bone graft to augment plate
fixation of humerus fracture non-union’s. Similarly Lin WP et al.
 in 2010 reported a mean union time of 22 weeks in patients
with humerus non-union where allogenic bone graft was used to
augment locked nailing.
The three failure cases in our series comprised of one
established previously infected gap non union of mid diaphysial
tibial fracture, one case of delayed union of fracture mid shaft
radius and ulna and another of fracture shaft femur. These
failure cases belonged to old fractures with hampered healing
potential that is delayed/ frank non union; it appears that in such
situations use of allogenic bone graft alone not sufficient as some
osteogenic potentiator is also required boosting the already
slowed healing process (Figure 3). The failure case of tibial
fracture non union on subsequent procedure revealed increased
vascularity at the fracture site with resorption of allograft
and presence of bone defect. These findings are suggestive
of allogenic bone graft being able to induce an inflammatory
reaction at the fracture site which may aid in healing process but
is not sufficient to bring about union as graft resorption occurs
at around 4 to 5 months.
Allogenic bone grafts are inherentely susceptible to infection
as the graft material can serve as foreign body. Infection rates
ranging from 4-12 % have been reported by different workers
Lord et al.  Surgical site infection associated with use of
allogenic bone graft shown by Ketonis C et al.  in their study
assessing bacteriological colonization of allogenic bone grafts
and found a high risk of graft being colonized by microorganisms.
Use of allografts in cystic lesions has been found to be associated
with increased infection rates (10.9%) reported in Indian study
by Goel SC et al.  Use of Vancomycin with allograft had been
studied in vitro by Witso E et al.  in 1999 and Buttaro MA et
al.  to prevent infection. Due to above reported complication
of infection this study involved the practice of vancomycin
impregnation and gamma sterilization of allogenic bone graft.
In our series of 18 patients no infection occurred in the post
operative period and irrespective of fact that prophylactic
vancomycin impregnation was used fractures united and was
not found to affect fracture union (Figure 4).
Allograft bone appears to serve adequate as filler for
bony defects. Augmentation of healing in difficult fracture
union cases with autologous bone grafts and or bone marrow
aspirate appears to be an ideal expander of quantity and
benefits of allogenic bone graft to expedited fracture union.
Vancomycin impregnation does not appear to hinder fracture
healing and graft incorporation process. None of the patients
showed postoperative infection may be pointing towards use
of vancomycin impregnation having benefit of preventing graft
related and surgical site infection.