[Secondary internal osteosynthesis after external fixation for recent or old open fracture of the lower limb]. / Ostéosynthèse interne secondaire après fixation externe pour fracture ouverte, récente ou ancienne, du membre inférieur.

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. Tibia was affected 17 times and femur 5 times (one bifocal fracture). In Gustilo's classification, we had 1 case of type 1, 12 of type II and 8 of type III. METHODS: We used 15 times the FESSA External Fixator and 6 times a monotube external fixator in emergency. We have done secondary 11 intra medullary nailing and 11 patients were treated by plating (one patient had both) 13 patients had a bone graft (cortico-cancellous graft). In the first group of patients (10 cases), the initial treatment gave us good results for both skin and bone healing. The external fixation was replaced by an internal one in order to accelerate bone consolidation and to allow an early weight-bearing. Removal of the external fixation was made at an average of 4 months postoperative. In the Second group (11 cases) the internal fixation was proposed because of an insufficiency of the external fixation leading to complications as: non union, mal union and bone defects. External fixation was removed in a mean time of 8 months. Internal fixation was completed by local bone autograft. RESULTS: 17 patients have been reviewed. Consolidation occurred with an average of 6 months after internal fixation 1 to 24 months. We had no deep infection but only 2 superficial ones. DISCUSSION: We chose 2 types of indication, and we called them programmed and for necessity. The first group of 10 patients whose stain was moderate and whose initial setting up had permitted a perfect anatomic reduction with a rapid wound healing. Internal fixation was performed after a short duration of external fixator. An early weight bearing was allowed so that the functional recovery could be obtained quickly. The second group is represented by patients whose internal fixation was done for non union, malunion or bone defect. In such a case autogenous cancellous graft was used to fill the defect.

Acute popliteal arterial injury: the role of angioscopy.

Accurate identification of arterial injury in the emergency setting constitutes one of the essential prognostic factors in patients presenting with acute popliteal arterial injury (APAI). The modalities of angioscopy performed intraoperatively by the vascular surgeon, including the details of how angioscopy can contribute to therapeutic decisions in this setting, are presented. Between June 1987 and August 1993, 26 patients presenting with 27 APAIs (one patient had a bilateral APAI) were treated at our institution. Eighteen (67%) lesions were due to closed trauma, three (11%) to shotgun pellets, three (11%) to knife wounds, two (7%) to iatrogenic wounds, and one (4%) to a bullet wound. Between June 1987 and January 1992 (group I, n = 20), treatment consisted of 15 (75%) saphenous vein bypasses and five (25%) local repairs. Pre- or intraoperative arteriograms were obtained in 14 (70%) cases. Three (15%) major amputations were required after popliteal reconstruction. Between February 1992 and August 1993 (group II, n = 7), two (29%) saphenous vein grafts and five (71%) local repairs were performed after routine intraoperative angioscopy. Arteriograms were obtained in six (86%) instances. No amputations were necessary in this group. As a complement to arteriography, intraoperative angioscopy can determine the extent and number of injuries, provides direct visualization of the intima of the entire femoropopliteal artery, even when the latter is obscured by thrombus, and ensures a final control of popliteal artery repair at completion. After angioscopy, local repair was possible more often (71% vs. 25%, p = 0.03) and treatment was associated with a better functional result (0% vs. 15% amputation rate, p = 0.04) in group II.

[Massive reconstruction of the acetabulum and proximal femur]. / Reconstructions massives du cotyle et du fémur proximal.

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). Results have been good based on patient satisfaction, mobility and consolidation of the allograft-bone junction. Complications included: post-operative death after major surgery for invasive tumours (n = 4); sepsis (n = 2); hip luxation requiring an anti-luxation crescent (n = 3); and aseptic serous effusion suggestive of possible immunologic reactions against the bone grafts (n = 3). These operations were compared with massive reconstruction prostheses, with arthrodeses with limb shortening and with hanging limbs, and in certain cases with interilioabdominal amputations.

[Analysis of stress in the knee using the finite element method]. / Analyse des contraintes dans le genou par la méthode des éléments finis.

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. Before this calculation, we needed to define the exact geometry of the structure, the elementary properties of the material and the conditions of the experimentation, particularly the strains that exist in the structure. Three simple examples are given: an osteosynthesis plate with an hole, a knee model that Maquet studied with the photoelasticimetry method and a bidimensional knee model. The results are traduced by different colours or by coloured ligns. The conclusion is to warn the orthopaedic surgeons to look carefully what model is behind the pretty coloured results.

[Massive osteocartilaginous allografts in the treatment of articular necrosis or loss of substance]. / Allogreffes ostéo-cartilagineuses massives dans le traitement des nécroses ou des pertes de substance articulaires.

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. Massive prosthesis are also used more and more often in case of recurrence or of prosthesis detachment. They may benefit from these techniques by using a sheath made of bank bone. These grafts allow increasing the stock of bone, which was so far constantly decreasing on the occasion of successive operations.

[X-ray computed tomography or MRI in the assessment of bone tumor extension]. / Scanner ou IRM dans le bilan d'extension des tumeurs osseuses.

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. The anatomical substrate and exact meaning of the MR signal of pathological tissue still remains to be specified. However, MRI already appears to be the essential examination for the assessment of local bone tumor extension. If it did not have contraindications, it could replace CT within the next few years.

[Total or partial iliac reconstruction using allografts from the bone bank]. / Reconstructions iliaques totales ou partielles à l'aide d'allogreffes de banque.

The reconstruction of massive pelvic defects following resection for tumour or damage from major trauma presents great technical difficulty. We have used cryopreserved allografts in patients to restore the normal anatomy and avoid major resection, such as a hemipelvectomy. This method avoids major limb shortening and impairment of function which occurs after trochantero-iliac or trochantero-sacral arthrodesis. Resection of tumour must be meticulous and complete in order to achieve a sound bed for the allograft. No problems were encountered in reattaching muscle insertions to the allograft, and skin healing was achieved without difficulty in all cases but one. In 2 patients involvement of nerve roots by tumour required their resection, with paralysis of the affected limb, but the overall function was satisfactory. In 10 patients removal of the hip joint was needed, and a total replacement was undertaken with cementing of the acetabular component into the allograft. Only one patient required a further operation because of partial necrosis of the allograft. Demineralisation was noted in some parts of the allograft between 18-20 months, but did not appear to affect function.