Fig. 20.1
Femur extracted
Fig. 20.2
Femur in the containing, sterile bag
Preservation Techniques
Preservation Methods
Cryopreservation in liquid Nitrogen at – 196 °C is used to avoid the formation of ice macrocrystals, we used cryoprotector ( 10 % DMSO), but the DMSO is toxic at a temperature higher than 8 °C. So, we have to decrease les temperatures to 6° before been in contact with the graft.
We have determined an optimal curve for decreasing the temperature (2°/′ from 6° initial −40 °C, then 5°/′ from −40 °C, −140 °C then put in liquid nitrogen at −196 °C) and rapid thawing in physiological à 41 °C permit the use of the graft after 30 min
Biomechanics and Immunology
Mechanical strength of the cortical allograft is only 50–60 % of the strength of normal bone during a period ranging from the 8th to the 18th month after the graft has been implanted. The fixation of the graft has to be perfect with a perfect contact between the recipient bone and the allograft.
Mechanical properties of the allograft can be changed by the preservation and storage processes (no irradiation – no heat – no ethylenoxyde – no acetone)
The preservation of the ligament structures, the capsule, and the meniscus is very important and the immunological response of the bone, the cartilaginous cells and ligament cells are very low. We can use immuno suppressants (like SANDIMMUM) if there is an immunological response (serosity surrounding the graft) (8 %) at the graft.
Transport
Can be made in liquid nitrogen or dry ice. If we use the graft with 12 h
We can thaw the fragment directly in the bone bank laboratory or in the operating room. We put it in sterile Liquid heated at 41 °C. It will also wash the DMSO from the tissue. After having thawed the graft we can use it for reconstruction of the skeleton in oncology, traumatology or loss of substance.
Massive Osteochondral Allografts
What is new is the knowledge of the Mechanism of Conservation and the behavior of Chondral Deep-Frozen Allografts:
The chondrocytes has to be protected to be able to fix the water molecules on the glyco-amino-glycans present in the cartilage
We cannot use a sterilisation by irradiation which would destroy all the cells and we have to use very carefully DMSO 10 % to stop massive ice cristal formation, not to impare the cartilaginous cellular function
The cartilaginous tissue is deep frozen and conserved in Liquid nitrogen at – 196 °C
The Cartilaginous Matrix has to have a normal tightness to protect the Chondrocytes
The sub-chondral bone has to be vascularized to survive, but the Cartilaginous cells only needs synovial fluid imbibition
The Cartilaginous cells are not replaced, and the one seen some years after grafting are those initially present in the graft
The Cartilage is a special tissue which don’t give immune response
If we have an immune response it is because of the surrounding tissue
Taken apart each component of the cartilage give an immunological response but when we graft the whole cartilage, there is no réaction
Material and Methods
1983–2012: 278 Patients had Massives Ostéochondral Allografts 197 Females/81 Males
27 Cases of Massive Osteochondral Acetabulum
3 total femoral reconstruction with osteochondrome femoral licard?? placed in the osteochondral acetabulum of the recipient
173 Patients with Knee reconstructions
Trochlea (29 cases)
Condyle (68 cases)
Patella (7 cases)
Tibial plateau (46 cases)
Total Lower part of Femur (14 cases)
Total upper part of Tibia (9 cases)
Some (specially in traumatologic cases) had different diseases
7 Cases of Wrist reconstruction
48 Cases of Shoulder reconstruction
16 Cases of Total Elbow reconstruction
7 Cases of Radius reconstruction
Used for
especially Oncologic diseases (73 % of the cases)
but also Traumatic Surgery (21 % of the cases)
and Iterative surgery (6 % of the cases)
Oncology
Most of the time we use Conservative treatment in oncologic surgery
Technical problems can lead to amputation
But the final Aim is to save the patient life and to make him have a good function ( Lumbo salvage surgery )
The absolute contra-indications are:
Voluminous Tumor
Infected Tumor
Skin Recoverage Problems
Malpositioned Biopsy
The relative Contra-indications are:
Irradiated Tumor
Very young patient
The result depends on the quality of the resection of the Tumor (Contaminated, Marginal, Large or Radical)
Traumatology
Most of our cases are surrounding the Knee but also at the upper arm.
Osteonecrosis
Lack of substance
Destruction of the Condyle, Trochlea or Tibial Plateau but also Elbow, and Schoulder
Iterative Operations
Specially at the Hip Joint and Knee
Results
Globally
The analysis of the function of the graft is made during the time of survival in Oncologic diseases. For the survival cases and the other nononcologic cases the Follow-up is of 28 Years: Good muscular and Ligamentary fixation in 76 % of the cases. Good healing at the junction. Allograft-Recipient Bone in 92 % of the cases. Good integration of the graft in 88 % of the cases. Immunological reactions occurred in 12 % of the cases.
Arthrosis and articular destruction occurred in 14 % of the cases due to ligamentary instability.
No more infections (4 %) occurred than occur in massive reconstructions especially when we use chemotherapy. Joint function was excellent in 131 Cases (76 %), Good in 17 Cases (10 %) Bad in 24 Cases (14 %).
In the hip, We obtained good function and no arthrosis with the Acétabulum reconstruction; even the size of the grafted cotyle is not exactly the same as the recipient femoral head.
In the knee joint, The function dépend of the stability of the graft and specially the ligamentary refixation.
In the shoulder, we have had some Necrosis of the Humeral head (4 cases) so that we use now more often Metal prosthesis surrounded by allograft . We have also to take care of the holes made in the upper part of the graft to fix the tendons on it. It can frgilize the graft and make it brake (3 Cases).
In the elbow, the initial function is satisfactoring but after some years (Brooks et al. 1969; Brown & Crues 1982; Burchardt & Enneking 1978; Burchardt 1983; Burchardt et al. 1978; Burwell & Gowland 1962; Burwell 1963; Burwell 1969; Burwell 1976; Burwell et al. 1963; Carr & Hyatt 1955; Carrel A. La conservation des tissus et ses applications en chirurgie. J Am Med- Techniques chirurgicales orthopédique 1984; Chalmers 1959) most of the joint become instable due to loosening of the ligaments fixing the elbow and the articular component destroy themselves but without pain.
Discussion: Global Follow-Up of 30 Years
We see tumoral reccurrencies when the tumor is not well taken off or specially aggressive
Infection can be seen, in the same percentage of cases (3 %) than the one we have when we use massive métallic prostheses. Some times when there is serum collection surrounding the graft, it can be seen as an infection. But when we make a biopsy or a procurement their are no germs. This liquid is an immunological response to the graft (8 % of the cases)
The Cartilaginous cells are still alive in the cartilage 10 or 20 years after grafting, they produce new Amino-glycans and fix Blue Colorants
If the thickness of the cartilage decrease, it is not clinically followed by pain because the cartilaginous tissue is not innevaled and we have very exceptionnally used a prosthesis
Most of the time the destruction of the joint, after grafting is due to ligamentary instability so we have to use primarily artificial ligaments or refix on the graft the ligaments of the recipient patient
Acetabulum and Pelvic Reconstructions with Massive Allografts
Revision arthroplasty of the hip and large-scale excision due to tumors are reasons for large losses of bone. Massive allografts make muscle refixation easier and provide the volume of bone needed for reconstruction of the loss of substance which is why we prefer them to massive metal prostheses. However their biological characteristics, their fragility on exposure to fatigue stresses and their immunological properties are subjects for discussion. Since 1982 we have been using 423 massives grafts preserved in the Bone Bank in Marseille for hip reconstruction (Acetabulum, Iliac wing, obturateur ring, whole hemi pelvis)
Etiologies
Tumoral Etiologies
Chondrosarcomas (57 % of the cases)
Fibrosarcomas
Ewing’s Tumors (21 % of the cases)
Plasmocytomas
Rhabdomyosarcomas
Giant cell tumor (18 % of the cases)
Infectious Etiologies
Echinococcosis
Sepsis
Hip Reconstruction after Revision Surgery
Acetabulum
Allografts
The graft is taken under very strict aseptic conditions in operating theatre
The graft is deep frozen and conserved in liquid nitrogen at – 196 °C with antibiotics. We can use it within 2 h after having thawed it
Surgical Techniques
Reconstruction of the Pelvis
The Patient is laid in ¾ dorsal decubitus position. The homolateral leg is left free to be mobilized. We have described a wide approach allowing the whole hemi-pelvis to be excised; The incision was started in the inguinal region taking the vessels into account, then extended downwards, towards the homolateral ischium, and upwards up to the antéro-supérior iliac spine.
Dissection of the Iliac and femoral vessels, spermatic cord, crural nerve, psoas, iliac muscles, pubis, bladder, obturator ring, lumbar and sacral roots, sacrum, iliac wing, femoral neck.
Osteotomies are performed at the end of the dissection when everything is under control (nerves and vessels, bladder and uretere, muscles and Bowel Loop).
Reconstruction of the hemi pelvis when an acetabular cup has been cemented directly on the bone allograft before it, is fastened. Fixation of the sacroiliac joint or of the sacrum.
One or Two plates are used after having been modulated inside the pubis and on the posterior wall. Refixation of the muscles on the bone. The femoral prosthesis is cemented in the desired position in the diaphyseal shaft of the femur after the canal has been prepared.
For 2 days the patient will remain in the intensive care unit. Walking and weight-bearing are permitted from the 8th day after operation. Total Weight –bearing is possible by 15–21 days postoperatively.
For Isolated Reconstructions of the Acétabulum
The approach used in revision surgery of the hip is a lateral external transgluteal route, creating a digastric muscle from the gluteus medius and with the vastus externus left connected to each other by trochanteric attachments. The femur is dislocated and freed from its acetabular attachments.
Then freeing of the acetabulum : ablation of the implant, of all the cement, and of any fibrosis, removing of the necrotic bone.
The femoral allograft(s) is (are) remodelled in such a way as to reconstruct the acetabulum perfectly after screwing them directly into the spongy bone. Further drilling is performed.
Anchorage points are drilled into the roof of the acetabulum, the pubis, and the ischium, through the allograft direct into the patient’s bone. The cement is applied when it is in its pasty phase.
Clinical Applications and Results
From the Carcinological point of view, the chondrosarcomas which were the main reasons for performing our pelvic grafts were always resected on a large scale.
There are very few relapses within the 10–15 years after operation but we see some after this period of time. On the other hand, the others sarcomas all resulted in the death of the patients after a longer or shorter interval.
Septic Loosening of prosthesis appear to us to be a good indication for surgery in two stages. A fracture of the allograft may heal completely. The allograft-host union has to be fastened by stable osteosynthesis and surrounded by spongy autograft.
The shafts of the prosthesis have to be cemented into the host femur as well as into the allograft. The number of septic complications is comparable in our series to that of the series using massive metal prosthesis. A number of serous effusions led us to review the immunology of the bone allografts
The Mega-Hip Prosthesis Surrounded By Allografts
Reconstructive metal mega hip prosthesis are commonly used, but they might be responsible of mechanical failures or instability due to muscle non fixation. One of the actual problems concerning articular allografting is the biomechanical behavior of the ligaments and the revascularization of the cartilage.
Autologous grafts, unlike allogenic grafts, have an important osteogenic potentie. But in as much as the procurement volume is limited, they do not permit massive bone or joint reconstruction when there as been partial or total resection as a result of either a bone tumor or a post-traumatic lack of substance.
Computerized Custom Made Mega Hip Prosthesis
Shape
To rebuilt the upper part of the femur destroyed by a tumor of after numerous operations. We have had, to study first the inner shape of the femur. The prosthesis has to have the same anatomical shape than the medullar bone. The form that has been given by C.A.O. is an italic S with a long inferior curve.
It is important to rebuilt exactly the inside anatomical aspect of the bone, for the prosthesis to be directly in contact with the cortical bone. If you use a straight stem you cannot obtain every where a good contact and you have stress schilding in some places of the bone and also you cannot use a massive allograft because you cannot introduce the stem in it.
Fixations
The Mega prosthesis has to be introduced very easily in a massive diaphyseal allograft without risks of breakage. We can use it with or without cement, but we think that the best utilisation is with cement in the upper part next to the allograft and also with cement in the lower part of the stem which is fixed in the receiver bone. The muscles surrounding the allograft will fix themselves directly on it. Some special fixation can also be used for the trochanteric muscles.
Clinical Applications
In reconstructive surgery, it is the first time that we increase the bone in using a prosthesis surrounded by allograft. In bone tumors when muscles and ligaments have to be removed, like in some traumatological cases, the use of massive osteocartilaginous allografts is not indicated because of the poor vascular surrounding of the graft and problems linked to articular instability. We think the best we can do in those cases, is to propose the use of massive metallic articular prosthesis surrounded by one allograft.
Prosthesis brings an immediate stability and allows the patient to walk a few days later, while the graft will permit the remaining muscles to fix themselves on it. This solution is the one choosen each time there is a reconstruction of the upper part of the femur (Fig. 20.3).
Fig. 20.3
(a) Implementation of bone substitution. (b) Prosthesis in place
Conclusion
The use of a megahip prosthesis surrounded by allograft has a lot of advantages. It allows muscular or ligamentary fixation and better biomechanical behaviour which decrease the risks of articular instability; no risk of articular necrosis means we can authorize a early loading; and especially we increase the volume of skeletal bone instead of decreasing it and that is a very new and important point.
Suggested Reading
Babin SR, Katzner M, Vidal PH, Simon P, Kempf JF, Keiling R, Schvingt E. Résection – reconstruction diaphysaire fémorale par allogreffe massive fixée par clou médullaire vérouillé. RCO. 1987;73:25–9.
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