Osteoarticular Allograft Research Articles

A new technique for reconstructions of large metadiaphyseal bone defects

Surgical Principles Tumors involving the metadiaphyseal region around the knee are often treated by intraarticular resection (and reconstructed by prosthesis or osteoarticular allografts) even when the subchondral bone could be saved and an intercalary reconstruction applied. This is due to problems associated with the reconstruction of the subarticular diaphyseal bone defects by conventional methods. Intercalary allografts (as well as cortical autografts) have significant complication rates in terms of delayed union or graft fracture: these would be significantly increased in those patients in whom an adequate osteosynthesis for support is not feasible. The use of a vascularized fibula alone is contraindicated because it cannot provide sufficient stability for the epiphysis and is too weak to allow early weight bearing. The Ilizarov technique (bone transportation) is extremely time consuming and it may be at risk in patients under aggressive chemotherapy (pin tract infection, possible interference with callus formation). Furthermore, the thin subarticular segment requires an additional ring across the joint, causing knee stiffness. The authors describe a new surgical technique to manage this surgical problem. The basic idea consists to bridge the bone defect using a massive allograft as a peripheral shell supporting a centrally placed micro-vascular fibular autograft. This technique was introduced by the first author in 1988 and preliminary results first described by Capanna et al. in 1989 and in 1991 [1, 2].

Metabolic and biochemical status of articular cartilage following cryopreservation and transplantation: a rabbit model.

To determine the fate of transplanted cryopreserved articular cartilage, an animal model employing the proximal humerus in the rabbit has been developed. Previous studies have been hindered by problems of postoperative joint instability, secondary injury due to immobilization, and paucity of cartilage for analysis. This experiment demonstrates the survival and function of transplanted cartilage by quantitative assessment of metabolic and biochemical parameters. Forty-five New Zealand white rabbits underwent transplantation of the right proximal humerus. In 29 animals, the proximal half of the humerus was resected and replaced by a cryopreserved osteoarticular allograft. Autograft procedures were carried out in the remaining animals. Following sacrifice at 3, 6, 9, and 12 months postoperatively, articular cartilage was analyzed for gross appearance, collagen synthesis, proteoglycan synthesis, and water, hydroxyproline, hexosamine, and hexuronic acid contents. The results indicate that the cryopreserved osteoarticular allografts retained their metabolic and biochemical integrity and behaved as viable and biologically functional units 1 year postoperatively.

Osteoarticular allografts for reconstruction in the proximal part of the humerus after excision of a musculoskeletal tumor.

Osteoarticular allografts for reconstruction in the proximal part of the humerus after excision of a musculoskeletal tumor.

Revision osteoarticular allograft transplantation in weight-bearing joints. A clinical review

The early results of revision osteoarticular allografts in weight-bearing joints are reported. Sixteen consecutive patients underwent surgery over a six-year period between 1982 and 1988. At the time of review eight patients (50%) had surviving second allografts with an average follow-up time of 48 months (range 12 to 87). Five patients were graded excellent according to the Mankin scale, one good and two fair. Eight patients (50%) required further surgery, but only two patients came to amputation.

Limb-Salvage Surgery in the Treatment of Osteosarcoma in Skeletally Immature Individuals

Sacrifice of major growth plates during resection and fixed-length reconstruction of a limb in a skeletally immature child with osteosarcoma may result in a significant limb-length inequality as growth progresses. A limb-length discrepancy in the humerus may cause minor cosmetic problems but does not generally result in a significant functional deficit. In the lower extremity, tumors about the knee, including the distal femur and proximal tibia, usually present the dilemma of whether limb salvage by arthrodesis, osteoarticular allograft, or endoprosthetic replacement would result in a significant limb-length inequality and whether amputation of the extremity is a preferable procedure. The techniques of rotationplasty and an expandable endoprosthesis have been successfully used for treating skeletally immature patients with osteosarcoma of the distal femur. With regard to survival and function, the results obtained with these innovative methods are favorable compared with those of a high above-knee amputation.

Scapular Allografts

Some malignant tumors of the scapula can be adequately treated by limb-sparing, partial, or total scapulectomy. However, resection of the glenoid portion of the scapula and total scapulectomy result in an unsightly shoulder. In an attempt to minimize the functional impairment and restore stability and cosmesis, scapular glenoid allografts offer a reasonably good biologic replacement. This report describes the cases of a 45-year-old woman and a 32-year-old man in whom massive osteoarticular allografts were used. In one patient, good stability, cosmesis, and function were restored after resection of the glenoid portion. In the other patient, shoulder stability, cosmesis, and limited function were restored after total scapulectomy. No reports of scapular allografts seem to have been previously published in the literature.

Pelvic Allograft

A 23-year-old man with a large chondrosarcoma of the right bony pelvis was successfully treated by limb-saving internal hemipelvectomy and anatomic reconstruction of the pelvis by a pelvic osteoarticular allograft including the acetabulum. Optimum anatomic fit was achieved at the hip joint as well as at the iliac and pubic host-graft junctions, which were fixed with plates and screws. This reconstruction restored stability, leg length, hip motion, and cosmesis. Five and one-half years postoperatively, the patient remained asymptomatic with good functional and roentgenographic results.

Osteoarticular allografts for reconstruction in the proximal part of the humerus after excision of a musculoskeletal tumor.

An osteoarticular allograft was used to replace the proximal end of the humerus in twenty patients who had had a wide excision of a bone tumor. Three patients needed a second allograft because the first became infected. All patients were followed for at least two years except for two patients who died. The functional results and complications of the twenty-three index procedures were evaluated. Function was excellent in one patient, good in eleven, fair in one, and poor in five. The allografts had advantages compared with other options for reconstruction (for example, prosthetic implants); these included restoration of the length of the bone, replacement of the articular surface, and sites for reattachment of the deltoid muscle and rotator cuff. We concluded that the complications do not preclude use of this procedure.

Inhibition of the Immune Response to Experimental Fresh Osteoarticular Allografts

The immune response to osteoarticular allografts is capable of destroying the cartilage--a tissue that has antigens on its cells identical to those on the bone and marrow cells. Osteoarticular allografts of the distal femur were performed in rats using various methods to attempt to temporarily inhibit the antibody response. The temporary systemic immunosuppressant regimens investigated were cyclophosphamide, azathioprine and prednisolone, cyclosporine A, and total lymphoid irradiation. The most successful appeared to be cyclosporine A, but significant side effects were observed. To specifically inhibit the immune response in the allograft antigens without systemically inhibiting the entire immune system, passive enhancement and preadministration of donor blood were tried. Neither was as effective as coating the donor bone with biodegradable cements, a method previously found to be successful. Cyclosporine A was investigated in dogs in a preliminary study of medial compartmental knee allografts and was found to be successful in inhibiting the antibody response and in producing a more successful graft; however, some significant side effects were similarly observed.

Massive allograft replacement of hemiarticular traumatic defects of the elbow

Four elbow osteoarticular allografts were done for four patients as salvage procedures for unreconstructable elbow fracture malunions. With a mean follow-up of 60 months (range, 12 to 72 months) all elbows were stable, free of pain, and had mean motion of 130 degrees active flexion and 27 degrees of flexion deformity, 67 degrees pronation and 62 degrees supination (preoperative mean: 104 degrees flexion, 42 degrees flexion contracture, 20 degrees pronation, and 34 degrees supination). Complications occurred in two elbows. One had a deep infection necessitating graft removal and subsequent regrafting. The second had an olecranon osteotomy nonunion. Elbow allografting is recommended as a salvage procedure for massive posttraumatic articular defects, bone loss, or malunion when neither arthrodesis nor conventional arthroplasty is indicated.

Cement coating of osteoarticular allografts in rats to prevent the immune response.

Recently, more attention is being paid to the treatment of the articular surface defect in the young, active individual. Resurfacing or "shell" allografts are being considered as one of the alternatives for treatment. The immune response by the host may be the chief obstacle to the successful use of fresh osteoarticular allografts. Since proteins on the surfaces of allograft bone cells are considered to be the principal antigens eliciting the immune response, we hypothesized that mechanical masking of these cells by a biodegradeable blocking agent might prevent the immune response. Osteoarticular allografts of the distal femur were performed in rats and the cut surfaces of the graft were coated with cement before implantation. In a preliminary experiment, six biodegradeable cement materials were tried (bone wax, zinc polycarboxylate, collodion, fibrin adhesive, zinc oxide, and isobutyl-cyanoacrylate). Of these, the zinc oxide cement and isobutyl-cyanoacrylate were effective in inhibiting the immune response observed in control rat distal femur allografts. A second experiment was performed using nine rats with zinc oxide and nine rats with isobutyl-cyanoacrylate cements. These were compared with 20 control rats that had allografts without cement coating. Eighteen of the control rats (90%) developed an immune response, while only 22% (2/9) of the rats with zinc oxide coating and 33% (3/9) of the rats with isobutylcyanoacrylate developed an immune response. In a third experiment distal femur allografts were performed in 13 rats using only the liquid component of the zinc oxide cement.(ABSTRACT TRUNCATED AT 250 WORDS)

Massive allografting for severe failed total hip replacement.

We are presenting the cases of five patients that illustrate the uses of large, frozen bone and osteoarticular allografts in dealing with severe structural deficiency about the hip joint associated with prior failed total hip replacement. The status of the grafts was assessed at a minimum follow-up of twenty-four months (average, thirty months). In four patients extensive grafts in the proximal part of the femur in conjunction with total hip-replacement components were used, and in the fifth patient a matched whole-joint transplant of the proximal part of the femur and the acetabulum was employed. The short-term clinical advantage of these massive grafts is clear, but the long-term results are uncertain.

Massive Osteoarticular Allografts in the Reconstruction of Extremities Following Resection of Tumors Not Requiring Chemotherapy and Radiation

Since 1976, 70 osteoarticular allografts have been used to reconstruct extremities from which tumors not requiring chemotherapy or radiotherapy have been resected. Allografts excised from cadavers were stored in the vapor phase of liquid nitrogen in liquid nitrogen freezers (-150 degrees) after exposure to 15% glycerol. Prior to their use, the allografts were thawed rapidly in either tissue culture or balanced salt solutions. Following resection of the tumor, the excised bone was replaced with allografts that were rigidly internally fixed with plates and screws or, occasionally, with intramedullary rods. Patients were observed carefully for complications and were subjected to functional evaluations. Complications did not include alterations suggestive of a pronounced immunologic response to the graft. Five patients developed either local recurrences or distal metastasis. Of the remaining 65 patients, followed for one year or longer, osteochondral allografts performed satisfactorily in 55 (84.6%). This group included eight patients with initial complications that were successfully treated. The group of ten patients with unsatisfactory results included four patients with fractures of the grafts, one with fragmentation of the humeral head, three with infections, and two with joint instabilities. Since all patients had either hemi-joint or quarter joint replacements, the overall results achieved so far have been rewarding. However, continued long-term observations of patients with allografts are indicated, as are studies that would allow for the improvement of cartilage preservation, decrease the incidence of fractures, and improve rigidity of internal fixation. The incidence of infection can be reduced by the improvement in surgical technique, particularly with reference to the wound closure.

Banking of Massive Osteoarticular and Intercalary Bone Allografts???12 Years?? Experience

Preparation and banking of massive osteoarticular allografts and intercalary bone allografts have been performed for the past 12 years. Careful selection of donors as well as extensive laboratory studies of the donor and the allograft have virtually eliminated the danger of transmitting disease from the donor to the recipient. The availability of a variety of allografts in the Tissue Bank allows for the selection, on an anatomic basis, of an allograft best suited for a particular recipient. The authors have supplied several hundred allografts to recipients in many institutions on the premise that excision, preparation, banking, and implantation of bone allografts constitute a clinical service. Thus, the surgeon who excises and prepares the allograft assumes a joint responsibility for the care of the recipient with the surgeon who implants the allograft. This establishes a close working relationship, which encourages frequent consultation between the parties concerned. This relationship is of particular importance in the initial evaluation of the patient and in determining which particular allograft will best serve a given patient. The experience at the authors' institution provides a model for a multiinstitutional facility that may serve as a base for discussion of the methodology involved in the excision, preparation, and storage of bone allografts. The costs associated with the operation of such a facility are not inconsiderable, but the cost of individual osteoarticular and intercalary allografts can be brought down by an increase in the efficiency of operation inherent in the processing of allografts from over 100 donors per year. During the past several years, the cost of excising and preparing intercalary allografts has been $600 per implant, while the cost for osteochondral allografts varied between $900 and $1,200. Such a large multiinstitutional facility offers the advantages of readily available allografts and quality control. However, because of the expense and complexity of operation, it may not be suitable for many medical centers.

Bone Allografts in Salvage of Difficult Hip Arthroplasties

Fourteen bone allograft transplantations were performed in 12 patients: five whole-hip osteoarticular allografts, eight acetabular wall, and one proximal femur with long-stem prosthesis. Average followup time was 19 months. Average patient age was 46 years. Acetabular grafts appeared healed. There was narrowing of joint space in all whole-hip allografts. However, joint narrowing did not correlate with functional results. Failures were attributed to collapse of the femoral head in one patient and nonunion at the host-allograft junction in two patients. However, even in primary failures, allografts provided bone stock to substitute for massive bone loss; this allowed for further reconstruction with endoprostheses. Intercalary segmental allografts combined with prosthetic devices gave the best results.

Radiographic Aspects of Massive Bone Osteoarticular Allograft Transplantation

Experience with 56 cases of osteoarticular allograft transplantation of the extremities is presented. Cadaveric allograft including a joint surface and a variable amount of shaft is used in the treatment of aggressive benign and low-grade malignant tumors involving a long bone near a joint. The preoperative radiographic evaluation is outlined. Thirty-four patients had an uncomplicated course. Twenty-two patients had complications including aseptic fracture, infection, and tumor recurrence. The radiographic spectrum of both complicated and uncomplicated cases is illustrated.

Newer Knowledge of the Immunology of Bone and Cartilage

By the use of modern techniques, the nature of the immunological response to bone and cartilage grafts is becoming clear. Fresh bone, whether cancellous or cortical, will elicit a cell-mediated immunological response; removal of the bone marrow has little effect in reducing immunogenicity. Antibodies against cellular components of the graft are detectable in the recipient only when host and donor have a disparity for the major histocompatibility (H) antigen. Treatment of bone grafts, for the bone bank, by freezing removes their immunogenicity with regard to antibody production but leaves them capable of stimulating the cellmediated immune response. Freeze drying, on the other hand, impairs immunogenicity for both types of responses. Cartilage, grafted alone, is probably non-antigenic as far as both immune responses are concerned and, although there have been a few reports of stimulation of CMI and antibody production by cartilage, these have not been confirmed. Cartilage cells do, however, possess antigens of the major H-antigen system. The cartilage graft is therefore antigenic but only feebly immunogenic, as the matrix proteoglycans protect the cells from the afferent arm of the immune response. Osteoarticular allografts, consisting of both bone and cartilage, sensitize the host due to their bone components. The effect of the immune response upon the bone allograft is to destroy the graft-derived first phase of osteogenesis which, in turn, leads to a poor or non-existent host phase of new bone formation in most allografts. The exact effector mechanism by means of which this destruction is brought about is not known. Bone grafts may be protected from the immune response by use of immunosuppressive measures. Cartilage enjoys a considerable measure of protection from immunological effectors by virtue of its matrix. If this breaks down then the cartilage can become permeable to antibodies. It is suggested that "lymphokines," produced by sensitized lymphocytes, may play some role in destroying the cartilage graft.