Chirurgie; memoires de l'Academie de chirurgie最新文献

The purpose of this study was to evaluate the load and the release of antibiotics obtained with an implant made of a macroporous beta tricalcium phosphate ceramic (beta-TCP). Two parameters have been assessed: macroporosity and external shape (beads and parallelepipeds). In vitro, the ceramic beads were soaked in a Vancomycin-aqueous-solution, and the load of the antibiotic was then evaluated: it was 9.3% of the weight of the 40%-porosity beads and 4.6% of the weight of the 20%-porosity beads. The release has been evaluated by elution in phosphate-buffered-saline (PBS). With a 20% porosity, 12 beads (6.3 mm, 279 +/- 38 mg) demonstrated a short an massive release which ended within the 32 first hours. On the opposite, the release was sustained until the third week for the 40%-porosity beads (6.9 mm, 353 +/- 25 mg), while only one third of the load was released during the first 24 hours. A macroporosity of 40% of the ceramic could allow a deep incorporation of the antibiotic in the beads and thus decrease the rate of release. The in vivo study compared the bone concentrations of antibiotics obtained after implantations of either parallelepipedical or spherical devices in the distal femurs of 14 sheep. The bone concentrations of Gentamicin obtained with parallelepipeds until the end of the third week were from 5 to 10 times the minimum inhibitory concentration of this antibiotic for staphylococci. On the opposite, beads achieved only low concentrations of Vancomycin and nearly no detectable Gentamicin in the bone. We hypothesize a negative effect of the fibrous tissue which fills the gaps between the beads, and which could impair the diffusion of the antibiotics into the bone.

Ependymomas and astrocytomas are the most frequent spinal cord tumors. They have the same clinical expression and the only treatment is surgery. We report the experience of two neurochurgical teams working in Lyon and Brussels with 171 operated patients, focusing on therapeutic strategies. Spinal cord ependymomas usually present as circumscribed benin tumors, complete exeresis is the best strategy. Long-term follow-up in 40 patients who were not given adjuvant radiotherapy showed no recurrence and satisfactory functional results. Astrocytomas are classically less well circumscribed but when exeresis is macroscopically complete, results are comparable with those of ependymomas as was found in 22 patients with long-term follow-up. Inversely, for infiltrating astrocytomas, pathology is usually malignant and prognosis is unfavorable despite radiotherapy or chemotherapy.

Lumboscopy is an endoscopic surgical technique providing direct visualization of the retroperitoneal space from the kidney hilium to the iliac bifurcation. We report our 10-year experience with this technique used to diagnose masses in the retroperitoneal space. This method is not very invasive and the morbidity is low. The sensitivity is greater than needle biopsy under CT guidance.

Beginning in 1990, the tension-free inguinal hernioplasties were adopted for the treatment of primary groin hernias in men. 1252 tension-free hernioplasties were performed in 1,076 men and followed for one to six years. Lichenstein's tension-free hernioplasty and Gilbert's sutureless hernioplasty were used, usually in combination. Anesthesia was local in 97% of the operations. 15 complications occurred (1.2%): one wound infection, one seroma, 12 hematomas, and one ilioinguinal neuralgia, 6 recurrences occurred (0.5%): 4 indirect, one direct and one femoral. No indirect recurrences have occurred since placing Gilbert's cone shaped plug in the deep ring. Tension-free hernioplasties consisting of a patch of polypropylene mesh plus a cone plug of the same material, placed in the deep ring when an indirect hernia is present, produce excellent results and are the preferred methods to manage the majority of primary inguinal hernias in men.

Carotid artery reconstruction (CAR) may be achieved through a variety of techniques. The method of choice is based upon the patient's symptoms, the diffusion of the atheromatous lesion in the internal carotid artery and the experience of the surgical team that usually deals with these patients. Between January 1987 and May 1995, we performed 185 CAR using saphenous vein graft. The indication for surgery was atherosclerotic occlusive desease in all patients, sixty-two per cent of whom were asymptomatic. In the early postoperative period one patient died of aspiration, two patients suffered a stroke (one major and one minor) and five patients had a transcient ischemic attack due to carotid clamping intolerance. Two late restenosis and two graft occlusions occurred. The cumulative operative morbidity and mortality rate was 1.6%. This series demonstrates than venous grafting for carotid reconstruction yields satisfactory short- and long-term results and is a valuable alternative to endarteriectomy. Follow-up by Duplex-scan revealed no evidence of morphological degradation of the vein grafts.

Plain radiograms are insufficient to evaluate the integrity of a graft used to replace acetabular tissue loss in reoperations for total hip replacement. The aim of this work was to compare radiographic, computed tomographic and magnetic resonance imaging findings. Two groups of patients including 12 hip joints in each were evaluated 5 years after undergoing reoperation for annular support. Allografts (5 cases) or xenografts (7 cases) were used in one group. Plain radiograms. CT-scan and MRI were performed in each patient. The graft-receiver bone borders were visible on the CT-scans but were not distinguishable on the radiograms. Bone and graft density and structure in contact with the implant could be determined on the CT-scan. MRI was difficult to interpret in most cases due to implant-induced artefacts and is not recommended in this type of reconstruction.

From October 1995 through March 1997, we performed 30 microsurgical reconstructions and achieved microvascular anastomoses in 16 with an automatic stapler (VCS) which allows insertion of titanium clips in the everted vessel walls. The mean age of the patients (15 men, 1 woman) was 42 years. Mean vessel diameter of the donor and recipient sites was 2 mm for the arteries and 3 mm for the veins. Recipient vessels had suffered radiation damage in 3 cases. Micro-anastomoses were performed in 26 cases, with end-to-end sutures in 24 and end-to side sutures in 2. There were 11 arterial procedures including 3 bypasses and 15 venous procedures with 1 bypass. Peroperative thrombosis occurred in 2 cases and were treated by undoing the anastomoses and resuturing manually. There were no early or late postoperative vascular complications. This clinical experience confirms the advantages of this mechanical approach to microanastomotic procedures for small vessels as previously demonstrated in experimental work: a system avoiding transfixation, rapid procedure, reliability.

Gravity of abdominal vessels traumatisms is secondary to multiple factors. It depends on the type of injured vessels, aetiology and associated lesions. Between September 1984 and March 1995, 22 abdominal vessel traumatisms in 16 patients (mean age: 39 years) were treated. At surgical exploration, 4 aortic and 2 renal vein lesions, 7 iliac artery and 3 renal artery contusions, 2 superior mesenteric artery dissections; 3 infra-renal vena cava ruptures and 1 superior mesenteric vein dilaceration were found. All lesions were caused by penetrant wounds secondary to firearm or blade injury or secondary to injuries due to ski or traffic accidents. In 5 cases, lesions were iatrogenic. There was no mortality in the post-operative period, 14 patients out of the 16 patients operated on have been followed during a period from 1 to 120 months.

This study concerns the fatigue behavior of a C/Peek hip implant. It is now well-established that the extent of bone loss around a total hip arthroplasty stem is related to stress shielding process. Due to a modulus mismatch between the bone and the implant material, the load transfer to the stem decreases the mechanical stimulus needed by the bone to maintain its structure. Because of its low modulus of elasticity and its good resistance to fatigue in aeronautical applications, the Fiber Carbon/Peek composite could potentially replace some of the metal alloys used in hip stem implant. After a literature survey on biomechanical performances of some fiber carbon composites, including AS4/Peek, experimental quasi-static and fatigue compression tests have been performed on AS4/Peek hip implants. The structural and mechanical characterization of the injection moulded composite material has been realized. The prosthesis compression and fatigue behaviour have been studied with a joint-stimulating apparatus immersed in a physiological solution temperature controlled. Instead of the low specimen homogeneity, no fatigue damage has been revealed either by X-ray observations of stiffness measurements, till ten millions of cycles. The quasi-static compressive fracture morphology has been analyzed by S.E.M. and have shown a good fiber matrix bonding. This mechanical results would suggest that AS4/Peek hip stem are worthy of further investigation as implantable prostheses.