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A critical review of publications on tracheal reconstruction is presented. The extent of the resection defect in terms of horizontal circumference or longitudinal extension determines the difficulty of the reconstruction. To allow a valid comparison, a classification of tracheal defects is proposed. The reconstruction materials can be subdivided into synthetic grafts, autografts, allografts, and bioengineering constructs. Reconstruction of tracheal defects greater than half of the tracheal length was not possible until recently. Numerous publications on animal experimental techniques, and rare human case reports show few successful outcomes. During the last five years, new reconstructive options have emerged: autograft of composite flaps mimicking tracheal architecture and bioengineered tracheal constructs.

A critical review of publications on tracheal reconstruction is presented. The extent of the resection defect in terms of horizontal circumference or longitudinal extension determines the difficulty of the reconstruction. To allow a valid comparison, a classification of tracheal defects is proposed. The reconstruction materials can be subdivided into synthetic grafts, autografts, allografts, and bioengineering constructs. Reconstruction of tracheal defects greater than half of the tracheal length was not possible until recently. Numerous publications on animal experimental techniques, and rare human case reports show few successful outcomes. During the last five years, new reconstructive options have emerged: autograft of composite flaps mimicking tracheal architecture and bioengineered tracheal constructs.

The author is neither anthropologist nor invested in social activities. He has learned some reviews of anthropology and some social and philosophical books since seven years. He describe not a general review but an analysis of these lectures according to the composite tissues allotransplantations (CTA). The discussion concerns anthropology and symbols, philosophical and social aspects. There is a natural umbilicus between the anthropological science and the surgical art according to CTA.

The latissimus dorsi flap based on the secondary segmental vessels, wich is termedreverseordistally basedlatissimus dorsi flap, has been used to repair major thoraco-lumbar defects, to close myelomeningoceles and to reconstruct congenital diaphragmatic absences. The arc of flap rotation is markedly restricted because the blood supply is segmental. It is the most important factor that limits the flap mobility and so restricts its use. The authors report an anatomic study of these secondary pedicles in order to improve the flap dissection and to extend the arc of flap rotation.The precise location of the secondary pedicles of the flap was determined by 24 anatomic dissections.The latissimus dorsi has 3, 4 or 5 secondary pedicles respectively in 50%, 25% and 25% of cases in the study. These pedicles take origin from the dorsal branches of the posterior intercostal arteries of the 7th, 8th, 9th, 10th and 11th intercostal spaces.The number of secondary pedicles is not constant. The entire flap can be safely based on 2 secondary pedicles when the latissimus dorsi muscle has 3 secondary pedicles. When this muscle has 4 or 5 secondary pedicles, the entire flap should be at least based on 3 secondary pedicles, particularly if the skin island is very far from the origin of these vessels.

Tissue engineering is a new domain, which allows some very unique studies of many human physiological mechanisms. This technology, based on cell capacity to reproduce a three-dimensional tissue with or without the help of biomaterials, is an interesting approach to study cells in an environment quite similar to the in vivo context. This article summarizes the LOEX's (laboratory of experimental organogenesis) scientific endeavor in tissue engineering in order to better understand some physiological or pathological mechanisms. Thus wound healing, stem cells, graft vascularization and cell interactions are domains where tissue engineering has already made a significant impact.

Tissue allotransplantation is defined by the transfer of tissues harvested from a cadaveric donor (in a brain dead condition) and revascularized to a recipient subject. This is based on the mastery of microsurgical techniques and on the induction of a therapeutic immunosuppression for the recipient. The first allografts (flexor tendon systems, knees and femoral diaphysis, hands, nerves, larynx) opened the field of composite tissue allotransplantation (C.T.A.) in reconstructive surgery. Immunosuppressive agents are now efficient enough to prevent the rejection of the allografts. The first patients operated on did not suffer from major or irreversible complications, but some potential side-effects of the immunosuppression remain an obstacle to the development of allografts in reconstructive surgery. The early functional results of the allografts are encouraging but their long term evolution remains uncertain. Some immunological (the chronic rejection) or psychological (the refusal of the graft and of its constraints) phenomenon might curtail the functional, aesthetic and psychological result. Currently considered as an extreme solution to exceptional indications, C.T.A. represents a tremendous hope for the future of reconstructive surgery.

Under specific conditions, French law authorizes organ donation despite the donor's seropositivity for certain infectious conditions. The recipient must however be informed of the potential risk of graft-related infection. Anonymous donation being the rule, the rights of the donor are respected since his/her serological status remains a medical secret. However, an exception to the rule of anonymous donation is allowed for organ donation between family members. In such a situation--often justified by the urgent nature of the transplantation--the donor's serological status would have to be revealed to the recipient, breaking the rule of medical secrecy. The physician who breaks the rule is simply implementing legal regulations (with the subsequent protection against any penal or disciplinary measures) but nevertheless performs an ethically questionable act. The recompense for donation would be an incongruent violation of personal rights. At the present time, there does not appear to be a satisfactory solution to this dilemma. The only solution that could be put forward would be to ask the donor to voluntarily inform the recipient of his/her seropositivity.

Despite the reticence of certain prominent scientists, there will be no moratorium on clinical xenotransplantation in the USA and a limited number of well-controlled trials will be enabled. There has already been some advances in cell and tissue xenografts with encapsulated porcine pancreas cells and porcine foetal neurones in patients with diabetes and Parkinson's disease. However, because of some porcine viruses are able to develop in human tissues, current and planned trials have been interrupted until routine viral detection tests are available. Several attempts have been made in the past, with animal organs (kidney, heart, liver) from various non-human primate species and conventional immunotherapy without success. Another major question now, is the choice of the animal donor species. Phylogenetically dose to man, non-human primates would be a right and logical choice. But, because of their procurement problems, it is likely that most future trials will be conducted with porcine organs from more performant transgenic animals, more powerful immunosuppressors and new therapeutic strategies based on the natural tolerance mechanisms.

Tissue allografts mainly include corneas, bone (and cartilage, tendon, ligament, aponevrosis), skin, vessels and cardiac valves. All these grafts have been widely used for many years and were the subject of a large number of experimental and clinical studies. The different steps allowing the obtention of different tissue allografts have in fact a common organization through tissue procurement and banking activities. Tissue banks have a central situation ensuring security, safety, traceability and distribution of tissues. Appropriate organization of the banks, and respect of high level standards are thus mandatory. Tissue transplantation activity in France has been studied through national surveys: they concern more than 600 hospitals and clinics, and grafts procured in France (excluding imported allografts) are around 15,000 a year. Precise regulation implied by the bioethical law published in 1994 and homogeneous organization of the activity allow the use of stringent and regularly updated standards, allowing the distribution to the patients of safe grafts procured in ethical conditions. The actual shortage of tissue allografts in France implies increasing procurement through a better organization of retrieval in hospitals and clinics and donation promotion.

The authors reported an early case of cauda equina syndrome after hemilaminectomy and discectomy for lumbar disc herniation. CT-scan revealed the migration of the free fat graft used for preventing peridural scar formation. Removal of the graft resulted in total patient's recovery.

The authors wish to show the difference between hand burns in children and adults. Throughout a group of 201 observations, they confirm the predominance in children of hands burns on palmar face. For them, the directed cicatrization by fat dressing associated with splints set in position of maximum cutaneous stretching is the first therapeutic. The early tangential excision and grafting is suitable only in rare indications, for instance in electric burns.