[Long-term outcome of large bone and osteochondral allografts].

Since 1978 the Marseille Bone Tissue Bank has stored 7466 specimens. Of these, 578 were large allografts, of which 529 have so far been used. The grafts are stored in liquid nitrogen with a cryopreserver, and are not sterilized by irradiation.

Human biological reactions at the interface between bone tissue and polymethylmethacrylate cement.

This study investigated cytotoxicity of cement fragments harvested from two prosthesis revisions by the MTT test using L929 fibroblasts and human osteoblasts. The results did not show any toxicity of the extracts prepared after 48 and 78 months implantation. We consider that no MMA monomer has been released from the cement fragments.

Using a finite element model to evaluate human injuries application to the HUMOS model in whiplash situation.

Study Design: In the field of numerical simulation, the finite element method provides a virtual tool to study human tolerance and postulate on potential trauma under crash situations, particularly in case of whiplash trauma.

Objectives: To show how medical and biomechanical interpretations of numerical simulation can be used to postulate on human injuries during crash situations. This methodology was applied to whiplash trauma analysis.

Functional and radiographic outcome of thoracolumbar and lumbar burst fractures managed by closed orthopaedic reduction and casting.

Study Design: Retrospective review.

Objectives: To determine clinical and radiographic outcomes of thoracolumbar and lumbar burst fractures without neurologic injury treated by closed reduction and casting. Patient factors associated with poor outcome are identified.

[Fractures of the shaft of the humerus: systematic plate fixation. Anatomic and functional results in 156 cases and a review of the literature].

Purpose Of The Study: Based on our experience with plate fixation of humeral shaft fractures and an analysis of the international literature, we attempted to answer the following questions. What functional outcome and what complications can be expected after surgery? Are the classical complications of open fracture surgery (screw fixation, wiring, plate fixation without compression.) as frequent after plate fixation using the Müller technique?

Material And Methods: We reviewed our series of 156 humeral shaft fractures (61 p.

[Interbody arthrodesis using a plasmapore titanium block. Mechanical and histological experimental study in sheep].

Unlabelled: A Plasmapore-coated titanium alloy block was implanted in ewes for the purpose of providing interbody fusion. Four blocks were implanted in each ewe: one uncoated block (without Plasmapore) serving as a reference specimen and three blocks coated with Plasmapore. Mechanical testing and histological study were performed on five ewes.

[Massive reconstruction of acetabulum and proximal femur].

Unlabelled: In revision hip surgery, allografts are useful for restoring the bone stock and allow the muscle fixation avoiding the use of massive metallic prothesis.

Material And Methods: We have reviewed 51 hip reconstructions with a follow up of 4 years and half (1982 - 1991). Indications were: - revision arthroplasties with destroyed acetabulum, - bone tumors (mainly chondrosarcoma).

[Future of bone allografts in massive bone resection for tumor].

Currently cryopreservation offers the best means of preserving bone tissue for allografts. At -196 degrees C all enzyme activity is halted and tissue preservation is unlimited. Perfect sterilization, adapted cryoprotection and controlled freezing and thawing are now part of the well-controlled process of bone preservation in bone banks.

[Reconstruction of the acetabulum after iterative surgery of the hip (report of 38 cases)].

Unlabelled: The hip revision surgery like oncology surgery may need massive allografts to rebuilt the acetabulum or an hemi pelvis. Since 1982 we have chosen to use deep frozen massive allografts instead of massive metallic prosthesis, resection, or osteosynthesis of the femur to the iliac bone or the sacrum. These last proposal seems for our patients too heavy, the functional results being always bad.

[Secondary internal osteosynthesis after external fixation for recent or old open fracture of the lower limb].

Purpose: The purpose of our study is to analyse the indications, results and limits of secondary internal fixation after external fixation for open fracture of the lower limb.

Material: Our series covered 21 patients treated between 1991 and 1994. There were 17 men and 4 women.

[Bone biomaterial].

The use of deep frozen allografts is not a recent technic. The evolution of the conservative technics authorize a sufficient preservation of osseous and cartilaginous structure. The clinical results are considered as good in most of the cases.

[Diagnosis and treatment of osteogenic sarcomas, techniques of reconstructions. Future prospects].

Patients And Methods: We have performed 34 massive bone-cartilage grafts with a follow-up of 2 to 7 years (1988-1993) including 5 complete joint grafts of the knee. Between 1988 and 1993, 8 massive diaphyso-metaphyseal bone grafts were performed. Joint reconstructions using massive bone-cartilage allografts are increasingly used in routine oncology surgery.

[Cytogenetics of bone sarcomas].

There has been much progress in the cytogenesis, and molecular biology of bone tumours such as Ewing sarcoma and osteosarcomas, greatly improving diagnostic possibilities and prognosis. Ewing's sarcoma is an indifferentiated sarcoma with round cells which usually occurs in children or adolescents. Ewing's sarcoma corresponds to 6% of all bone tumours.

[Massive reconstruction of the acetabulum and proximal femur].

Bone allografts are used in situations of repeated hip surgery to repair bone loss and allow muscle fixation without excessive use of massive metallic prostheses. We examined 51 cases of hip reconstruction after a mean follow-up of 3 and a half years. Indications were: reoperations on arthroplasties, usually after the weight carrying areas of the acetabulum had been destroyed; repeated operations on the upper extremity pellucid femurs; bone tumours (especially chondrosarcomas).

[Analysis of stress in the knee using the finite element method].

The increase in the number of the studies of the stress around the anatomic prosthesis by the finite element method incited the authors' work. Our purpose was to study the methodology of a technic with simple cases. The finite element method is a method of calculation which allow the calculation of the displacement under the stresses of each element that we created in the structure.

[X-ray computed tomography or MRI in the assessment of bone tumor extension].

Conservative surgery of primary bone tumors, which has become possible owing to the progress made by chemotherapy, must be carcinological, and it is therefore based on a thorough assessment of local tumor extension. CT and MRI have proven their great value for this assessment. While CT clearly shows the calcified tissue and the extension into soft tissue, MRI is more effective to delineate the tumoral and intraosseous margins and, more importantly, for the exploration within bone, for which it has the advantage of making a study in all planes possible.

[Massive osteocartilaginous allografts in the treatment of articular necrosis or loss of substance].

The problem of articular reconstruction arises increasingly often during the treatment of bone tumors because of the progress made in the choice of the chemotherapy. The excellent tolerance of osteocartilaginous allografts allows extending their indications to common traumatology. The biological, immunological, mechanical and clinical studies offer encouraging prospects in the field of massive osteocartilaginous grafts.