الفهرس 
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Abstract
Malignant bone tumors represents a challenging problem for orthopedic surgeons, In
Egypt; incidence of malignant bone tumors is about 28 case/1000,000/year, representing
about 1.9% of all malignant tumors. [84] Functional impairment is the most disappointing
sequel of the disease or even of the treatment; especially when amputation emanates as a
treatment of choice in many cases.
Currently, limb salvage surgery is the treatment of choice for malignant
bone tumors due to advances in multimodality therapy, diagnostic imaging, radiotherapy,
chemotherapy, and operative techniques. Surgeons have multiple alternatives for
reconstruction of large bone defects following malignant bone tumor resection, including
massive endoprosthesis, allograft, composite arthroplasty, Rotationplasty, induced
membrane technique, and distraction osteogenesis. Biological reconstruction involving
the recycling of resected tumor-bearing bone is popular in some countries for socioreligious reasons. These bone tissues need first to be treated to kill cancer cells that may
be present before they are replanted into the patient. Treatment methods include
irradiation, autoclaving, microwaving, and pasteurization. However, these treatment
methods require special equipment and strict thermal control. In addition, some
treatments cause thermally induced bone weakness with loss of osteoinduction. Recently,
Tsuchiya et al. reported success with a new method that takes the opposite approach,
utilizing hypothermia rather than hyperthermia to treat tumor containing autografts.
Specifically, the method uses liquid nitrogen at −196°C as a cryogenic agent to sterilize
tumor cells in the bone. Development of their method was based on in vitro and in vivo
studies of the hypothermic effects of liquid nitrogen on osteosarcoma proliferation.
Functional outcome of frozen bone in children
Because liquid nitrogen is a liquid substance that can be contained easily during the
operation, we hypothesized that we can be able to develop a new surgical technique that
no longer required total En bloc excision of the tumor from an extremity but, instead,
would enable us to excise the bone-containing tumor partially from the limb and then
rotate the bone so it could be immersed in an adjacent container of liquid nitrogen to
create a pedicle frozen autograft.
This study was conducted to evaluate the long term results of reconstruction by frozen
bone autograft after resection of malignant bone tumors in children. It included 33 child,
mean age was 13±3.3y (6-18 y), they were 14 child (below 12years) and 19 adolescents
(12- 18 years), they were 17 girls and 15 boys. Mean follow up was the mean follow-up
period for the all patients included in this study is 74±46.7 m (2-221 m), for those who
died (8 patients) was 23.5± 11.6m (2-44 m), and for survivors was 77.4± 43.3 m (33-221
m). Pathological diagnosis was osteosarcoma in 31 patient and Ewing sarcoma in one
patient and undifferentiated round cell sarcoma in one patient. In 19 cases, the lesion was
in the femur, in 11 patients it was in the tibia, in two patients was in the humerus, and in
one patient was in the calcaneus.
Patients were evaluated clinically for survival, oncological status, occurrence of
metastases, functional outcome using MST score, and radiologically for graft survival,
union of the graft, complications and LLD.
Several studies have shown little difference between amputees and those who undergo
limb salvage surgery in quality of life when assessed using psychological outcomes or
ability to achieve endpoints such as marriage and employment. Musculoskeletal Tumour
Society (MSTS), TESS, and PROMIS scoring systems have been used to assess the
functional outcome following limb salvage surgery. We chose the MSTS score as a
functional score for patient evaluation.
Functional outcome of frozen bone in children
In this study, eleven patients remained disease-free, those who lived with no
evidence of disease were twelve, two were alive but with disease, and eight
patients died of the disease. Five and ten year rates of survival were 75.76%. Graft five
year survival rate was 83.86%, while ten year survival was 78.79%, and it was 94.44%
intercalary reconstruction, 83.33% and 41.67% for composite graft, and was 50%& 33.3
% at five and ten years respectively for osteoarticular reconstruction.
Function on the Enneking scale was excellent in 28 patients (84.84%), good in one
(3.03%), fair in one (3.03%), and poor in three (9.09%). Average MSTS score for all
patients was 23.67± 6.58 (5-29). Average union time was 8.4±2 (6-12). Local recurrence
occurred in four cases (12.12%), all recurrences were from the soft tissue component
from the frozen bone nor from the host bone. Some orthopedic complication had
occurred, fracture, infection, non union, and graft collapse.
Conclusion:
After final evaluation of the results, we conclude that:
1- Several reconstruction options for limb salvage after malignant bone tumor
esection in children coexist.
2- Biological recycling has the following advantages:
A) Biological & Physiological healing
B) Potential of remodeling
C) Excellent soft-tissue attachment
D) Restoration of natural limb.
3- Freezing using liquid nitrogen preserve bone architecture, BMP, preserve mechanical
properties of the bone, less complication than other biological methods, cheap, easy,
enhances osteoinduction and osteoconduction, short time treatment, with perfect fit.
4- Prerequisites for this technique are patient with primary/secondary bone tumor, with
good response to chemotherapy, with non osteolytic lesion.
5-Functional outcome is better than other options in children.
6-Complications are comparable to other reconstructive options in children
7-Contraindication of using this technique including recurrent cases, poor response to
chemotherapy, purely osteolytic lesions.