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J Benoit

Publications and source records attributed to J Benoit.

At least 37 records · Page 2Linked to original sources
PubMed1996

Heparin-like polymers derived from dextran enhance colonic anastomosis resistance to leakage.

A new tissue repair agent, RGTA11, is described for its ability to enhance colonic anastomosis repair and resistance to leakage. RGTA11 is a dextran derivative containing 110% carboxymethyl groups, 2.6% carboxymethyl benzylamide groups, and 36.6% carboxymethyl benzylamide sulfonate groups. RGTA11 was deemed efficient to protect the heparin-binding growth factors FGF2 against trypsin digestion. By this property RGTA11 mimicked heparin or heparan sulfate. We have also found that RGTA11 protected TGF beta 1 against trypsin digestion while heparin did not. RGTA11 was then tested in an in vivo wound-healing model of colonic anastomosis. Our results indicate that after 48 h, RGTA11- or RGTA11/FGF-2-treated animals presented a resistance of the anastomosis to leakage which was increased twofold (p < 0.05) over untreated controls. After 96 h and until day 7 there was no more difference with control animals. Our results suggest that RGTA11 presents potential clinical interest by preventing earlier leakage of colonic anastomosis.

Anastomosis, Surgical↗
PubMed1996

The effect of in vivo retinal cooling on the electroretinogram of the rabbit.

PURPOSE: Studies reporting the effect of retinal cooling on the electroretinogram of mammals have, in most cases, made use of an in vitro approach where the temperature of the retina was lowered by reducing the temperature of the bathing media. The purpose of our study was to investigate, in rabbits, the effect of in vivo retinal cooling using an experimental approach never before reported in order to determine if some of the temperature-related ERG effects previously shown could have been, in part, amplified by alterations in the physiological status of the retina due to preparation for in vitro study. METHODS: In order to reduce the temperature of the retina, a 20 gauge plastic tubing was coiled around the eye from the limbus to the optic nerve head and glued to the sclera. Cold (15 degrees C) tap water entered the tubing at the limbal extremity and exited (18 degrees C) at the optic nerve extremity. Intraretinal temperature was measured to be within 1 degrees C of that of the circulating water. RESULTS: Our results indicate that with progressive retinal cooling the a- and b-waves are gradually reduced to 66.9 +/- 17.3 and 90.9 +/- 10.4% of control respectively. The most dramatic temperature induced ERG modifications were observed in the oscillatory potential recordings where the mean summed OP amplitude (OP2 + OP3 + OP4) was reduced to less than 23.9 +/- 13.5% of control with OP2 being the least affected. The peak times of all the ERG components were significantly delayed with cooling. CONCLUSIONS: Of all the ERG components examined, the OPs were those most severely affected by our manipulation. We believe that our results constitute further evidence in support of the concept that the OPs are more sensitive to retinal disturbance than the b-wave.

Animals↗
PubMed1996

[Arthroscopic management of recurrent anterior shoulder dislocation by combining a labrum suture with antero-inferior holmium:YAG laser capsular shrinkage].

Current arthroscopic treatments do not address satisfactorily the capsular redundancy frequently associated with the Bankart lesion in recurrent anterior dislocation. Although the Bankart lesion heals, many of the recurrences after arthroscopic procedures are due to capsular redundancy and the laxity of glenohumeral ligaments. We propose that laser-assisted capsular shrinkage (LACS) be combined with arthroscopic labrum reattachment. As shown by Market et al., significant capsular shrinkage can be achieved by the application of non-ablative Ho:YAG laser energy without detrimental effects to the relaxation properties of the tissue. For 1 year we have used LACS together with labrum suture in 18 shoulders in 18 patients (mean age 24.6 years). All patients suffered from chronic anterioinferior recurrent dislocation. The labrum suture was realized by an anterior reattachment (REVO screws, Linvatec, USA) or by transglenoid suture. Two or three sutures were passed through the torn labrum with 2/0 non-absorbable suture material. The LACS procedure was performed with a holmium:YAG laser (VersaPulse, Coherent, USA) at an energy of 10 W (1 J, 10 Hz) with a 30 degrees curved handpiece. All patients were immobilized in a sling for 4 weeks postoperatively. Physical therapy was begun at 1 month with passive and active exercise. To date, none of the patients have had a recurrence. Seven of 18 patients returned to their previous sports activity, and at the same level. None of the patients had an iatrogenic lesion due to the laser application or labrum suture. Compared to the other shoulder, the loss of external rotation with the arm 90 degrees abducted was 30 degrees at 4 weeks and 10 degrees at 4 months. We think that the LACS procedure is a good treatment for the capsular redundancy that is frequently associated with Bankart's lesion in recurrent anterior dislocation and is probably responsible for the high failure rate in current arthroscopic procedures. Our results are short-term results, but we expect the capsular shrinkage associated with the labrum reattachment will provide a long-term success rate that is comparable to open procedures.

Adult↗
PubMed1996

[Laparoscopic cholecystectomy in obese patients: 110 cases].

110 obese patients who underwent a laparoscopic cholecystectomy were compared with a group of controls, the operative time (108 mn), the conversion rate to laparotomy (4.5% vs 1.8%) and the incidence of drainage (26 vs 11%) were significantly raised in the obese patients. However there was no difference in the mortality (0), the feasibility of intraoperative cholangiography, the hospital stay, the morbidity or the time off work when compared with the controls. In particular the incidence of wound infections, thromboembolic or respiratory complications (frequent in conventional surgery on the obese) was not significantly different to the control group operated on laparoscopically. This study supports that laparoscopic approach is an elective procedure for obese patients.

Adolescent↗
PubMed1996

[What are abdominal painful syndromes of unexplained origin? Prospective study: 99 patients followed for three years].

99 patients, 67 of whom were female, with a mean age of 25.5 years, were admitted as emergencies between 1991 and 1992 for acute abdominal pain of unknown aetiology. The follow-up, carried out prospectively, was 100% at 1 month, 98% at 6 months, 95% at 1 year, 84% at 2 years. The patients were divided into 3 groups: group I: 42 patients only underwent investigations; group II: 31 underwent laparoscopy, and the appendix was left in place after being considered to be normal by the surgeon; group III: 26 underwent laparoscopic appendicectomy for a histologically normal appendix. For 90% of patients, the painful episode never returned. In the other cases the pain returned within one year, but there was no difference between the three groups (11.2%, 9.6%, 11.5%) (ns). The causes found at the second admission were largely genital, or rare diseases (Crohn, Spiegel hernia). 2 patients were operated for acute appendicitis, not recognized in Group I. In those who had a laparoscopy (Group II and III), the incidence of persistent pain was identical whether the appendix was considered to be normal by the operating surgeon or found to be normal histopathologically. This study suggests that: after admission for acute abdominal pain of unknown cause, the incidence of recurrence of pains is of the order of 10% within one year; the investigations carried out during the patient's admission, allowed the exclusion of serious diseases for three years; the risk of missing a true appendicitis is small (2.5%) and has no prognostic significance; the finding of a normal appendix during laparoscopy should not necessarily lead to its removal; one year follow-up is sufficient to assess the outcome of abdominal pain of unknown cause.

Abdominal Pain↗
PubMed1996

Osteonecrosis of the hip in renal transplant recipients. Changes in functional status and magnetic resonance imaging findings over three years in three hundred five patients.

OBJECTIVE: to conduct a retrospective study of the appearance and course of magnetic resonance imaging abnormalities in avascular osteonecrosis of the femoral head in renal transplant recipients and of potential relations between these abnormalities and the functional outcome. PATIENTS AND METHODS: among 305 renal transplant recipients, patients with pain in the hips or knees underwent radiographs and magnetic resonance imaging studies of the hips and, if appropriate, of the knees. The mean time interval between these studies and transplantation was 8.9 months. The outcome was evaluated based on the Lequesne index and findings from a repeat magnetic resonance imaging study after a mean follow-up of 33 months since transplantation. The criteria developed by Mitchell et al. were used to diagnose osteonecrosis on magnetic resonance images. The size of the necrotic area was estimated using the tracing paper method as < 25%, 25-50%, > 50% of the surface of the femoral head. Eleven patients were treated by elimination of weight-bearing and conservative treatments and 15 underwent core decompression (radiographic stage I or II). RESULTS: Fourteen patients (4.5%) developed osteonecrosis of the femoral head, which was bilateral in 12 patients and unilateral in two: thus, the total number of hips with osteonecrosis was 26. The first magnetic resonance imaging study disclosed a crescent-shaped area of low signal intensity in 25 cases, most of which were mild in severity as assessed on radiographs (Arlet and Ficat stage I or II). Extensive necrosis was found in most cases at the first evaluation (> 25% in 15 cases and > 50% in eight). The surface of the necrotic area (as assessed irrespective of the treatment used) remained unchanged in 20 cases and decreased in six. In half the cases the hyperintense signal from the sequestrum converted to a hypointense signal after a mean follow-up of 39 years. A poor functional outcome (Lequesne's index > 7 or total hip arthroplasty) was seen in 61.5% of cases, irrespective of the treatment used. CONCLUSION: Avascular osteonecrosis of the femoral head precipitated by corticosteroid therapy in renal transplant recipients occurred in 4.5% of patients immediately involved a large segment of the epiphysis, and usually remained stable over time, although a decrease in the size of the lesion was seen in a few cases. Overall, the functional prognosis was poor, with a Lequesne's index greater than 7 or total hip arthroplasty in two thirds of cases after three years' follow-up. The incidence of avascular osteonecrosis of the hip in renal transplant recipients has decreased since 1980, when cyclosporin was introduced and doses of corticosteroids used to treat rejection episodes were diminished.

Adult↗
PubMed1996

[Fractures of the anterior rim of the distal part of the tibia. Apropos of a series of 38 cases].

PURPOSE OF THE STUDY: Fracture of the anterior rim of the distal tibia is a rare injury. This fracture seems less serious than other pilon fractures but its treatment is often difficult and didn't give better results. The aim of this study was to describe problem we dealed with and to suggest solutions in order to improve long term results. MATERIAL: The study included 38 cases, treated in 5 Paris district trauma centers, with a minimal follow-up of 6 months. All patients were asked for clinical and radiological review between september 92 and march 93 ; otherwise, latest review datas were used. METHODS: Authors suggest a radiological classification based upon type, width and talus anterior displacement. Different surgical procedures were performed for 33 cases (screw, plate, external fixation) ; conservative treatment was used 5 times (non weight bearing plaster cast). Anatomical reconstruction was analysed. Functional results scoring system included pain, global abilities and ankle range of motion. Ankle arthritis was rated according to 1992 SOFCOT scoring system at 1 and 3 year follow-up. RESULTS: Follow-up ranges from 6 months to 11 years (average 28 months). 55 per cent of cases were lost for review with 1 year mean follow-up. 45 per cent of patients were recently tested with 4 year mean follow-up. Three ankles had joint fusion 6 to 18 months after trauma. Functional result was poor. For 35 ankles analysed 1 out of 4 remained totally painless (9 cases), 1 out of 2 had a good function (20 cases) and 1 out of 3 normal X-rays (12 cases). Arthritis was found for 2 ankles out of 3 after one year follow-up (16 cases out of 23). Loss of reduction or incomplete reconstruction seemed the most important point (13 cases out 38, 13 cases after 35 surgical procedures). DISCUSSION: Many patients didn't get a long term evaluation, and this study has no statistical value. Anyway, function loss was always early on a weight bearing joint. A perfect and stable reconstruction gives a higher rate of good result (11 out of 14). Analysis of cases with anatomic imperfection leads to recommendations: fixation of separation fracture, even undisplaced, bone grafting to correct impaction, appropriate use of external fixation for neutralization. CONCLUSION: Better results should come from a better analysis of the bone lesions : separation, impaction or mix fracture. This analysis leads to appropriate surgical procedure which give back a stable and anatomic distal tibia. External fixation can be usefull for immobilization ; this can't avoid open reduction and internal fixation of the fracture. Bone grafting can be useful for impaction fracture.

Adolescent↗
PubMed1996

[Synovial chondromatosis and chondrosarcoma. A study of the relationship between these two diseases].

PURPOSE OF THE STUDY: This retrospective study concerns six patients in whom chondrosarcoma was suspected to develop in synovial chondromatosis. We discuss for these cases different diagnosis. The authors expose the clinical signs and radiological aspects which suggest malignant transformation. We report the indispensable criteria for established diagnosis of malignant transformation of synovial chondromatosis and appropriated forms of therapeutic management were suggested. MATERIALS AND METHODS: Six patients, 3 males and 3 females from 36 to 58 years of age were included in this study. Three patients presented 6 months, 3 years and 25 years history of synovial chondromatosis of the knee joint. When the malignant transformation appeared, a surgical biopsy was performed and the pathologist diagnosed a chondrosarcoma in all cases. For the other three patients, the chondrosarcoma and synovial chondromatosis were diagnosed at the same time. The localization was shoulder, hip and knee. A surgical biopsy was performed and the pathologist diagnosed chondrosarcoma. Synovial chondromatosis was diagnosed by histologic examination of the resection or amputation specimen. TREATMENT AND RESULTS: Four patients had thigh amputation, one patient had "en bloc resection" of the hip-joint and the last patient had resection of the shoulder joint. In all cases, the histologic examination diagnosed chondrosarcoma and synovial chondromatosis. All patients were free of disease. DISCUSSION: The malignant transformation of synovial chondromatosis is rare but this diagnosis must be established to perform appropriate treatment. Other possible diagnosis are: low grade synovial chondrosarcoma initially diagnosed as a synovial chondromatosis. Bertoni believes that all cases of malignant transformation of synovial chondromatosis are initially low grade chondrosarcoma. We believe that his criteria are too strict for diagnosed chondrosarcoma. coexistence of synovial chondromatosis and synovial chondrosarcoma. These 2 diagnosis are extremely rare and their coexistence are unlikely. secondary synovial chondromatosis developed into chondrosarcoma. We don't have histologic criteria to confirm this diagnosis in all our cases. The symptoms that should suggest a malignant transformation of synovial chondromatosis were: rapid late deterioration of clinical conditions, bone invasion diagnosed by X-ray films and medullar invasion discovered by MRI. According to us, the indispensable criteria to diagnose malignant transformation were: 1.) histologic diagnosis of synovial chondromatosis established before diagnosis of chondrosarcoma, 2.) histologic diagnosis of chondrosarcoma on the same anatomic site as the synovial chondromatosis, 3.) diagnosis of chondrosarcoma and synovial chondromatosis on the same resection specimen. Only the three first cases were in accordance with these criteria. The treatment must be a "en bloc resection" of the joint or an amputation. CONCLUSION: Malignant transformation is rare, but this diagnosis should be established to perform adequate treatment. This diagnosis should be suspected when a rapid deterioration of the clinical status appeared and when bone involvement was detected by MRI. However, the danger still lies in the misinterpretation of the synovial chondromatosis as chondrosarcoma. This diagnosis can be made with clinical, radiological and pathological criteria. The treatment must be a wide resection or an amputation.

Adult↗
PubMed1995

Light adaptation of the human photopic oscillatory potentials: influence of the length of the dark adaptation period.

Photopic electroretinograms recorded immediately after a period of dark adaptation show a regular increase in amplitude with time spent in light. The retinal mechanisms at the origin of this light adaptation effect remain obscure. The purpose of this study was to investigate the duration of the dark adaptation period needed to produce an optimal light adaptation effect as demonstrated by photopic oscillatory potential recordings. Our results indicate that the light adaptation effect can be separated into two distinct processes. The first one, activated early in the dark adaptation process, reduces the amplitude of the fourth oscillatory potential to 32% of control after less than 5 min of dark adaptation, while the second process, activated after more than 10 min of dark adaptation, appears to impact solely the amplitude of the earlier oscillatory potentials 2 and 3. Our results suggest that the light adaptation effect is mediated by two distinct retinal pathways or mechanisms.

Adaptation, Ocular↗
PubMed1995

Maturation of binocular pattern visual evoked potentials in normal full-term and preterm infants from 1 to 6 months of age.

The purpose of this study was to evaluate the visual development of preterm infants from 1 to 6 mo of age, using the pattern visual evoked potentials (VEP) in response to three check sizes: 60, 30, and 15 min of arc. Pattern VEP were recorded in 24 full-term and 24 preterm infants (26-36 wk of gestation). The results showed a rapid visual maturation between 1 and 3 mo, followed by a slower progression over the next 3 mo, in both groups. The implicit time of the P100 wave of the pattern VEP was also found to shorten with increasing check sizes. The maturation of pattern VEP in preterm infants was shown to be related to their gestational (or corrected) age rather than their postnatal age. The pattern VEP obtained in response to a 60-min check size in preterm infants aged between 1.5 and 2.5 mo (corrected age) showed a tendency for a faster maturation than those of full-term infants. Our results suggest that within the first 6 mo of age, pattern VEP response is useful to monitor visual development in full-term infants as well as in preterm infants using corrected age.

Age Factors↗
PubMed1995

Destructive arthropathy of the hands in chronic hemodialysis patients. A report of seven cases with pathological documentation.

Destructive arthropathy of the hands is common in chronic hemodialysis patients. The clinical and histological features in seven cases are reported. There were five females and two males aged 45 to 78 years. Hemodialysis duration at the time of surgery was 48 to 228 months (mean 92 months). Four patients had arthrodesis, two had insertion of silastic implants and one had a diagnostic surgical biopsy. The site of the surgical procedure was a distal interphalangeal joint in three patients, a proximal interphalangeal joint in one, a trapeziometacarpal joint in two, and both a proximal and a distal interphalangeal joints in one. All seven patients had severe destructive arthropathy responsible for pain and instability. Roentgenograms showed joint space obliteration and subchondral erosions or lysis, without osteophytosis. Several finger joints were involved in six of the seven patients. Histologic studies of the synovial membrane (n = 7) and subchondral bone (n = 4) found no amyloid even in the three patients with clinical or roentgenographic evidence of amyloidosis at other sites. Electron microscopy studies were done in two patients and failed to disclose crystals or amyloid. Our findings demonstrate that destructive arthropathy of the hands in hemodialysis patients is not a manifestation of dialysis-related amyloidosis. The pathophysiology of the condition remains poorly understood.

Aged↗
PubMed1995

[Internal plantar flap. Apropos of 30 cases].

Thirty medial plantar flaps were used in twenty seven patients with large defects in soft tissues of the lower extremity. We performed that flap described in 1981 by Harrison for ankle defects (9 cases) and heel defects (21 cases). The etiology of the defect was a traumatic avulsion in 14 cases, a sole pressure in 10 cases and neurologic ulcer in 6 cases. The surgical procedure was performed in 5 operative sequences: 1--excision of the receptor site 2--disection of the posterior tibial artery and plantaris medialis artery 3--raising of the flap including plantar skin and aponeurosis, respecting the flexor hallucis brevis muscle 4--rotation of the flap and suture on the receiptor site 5--skin graft on the donor site Antibiotics were used according to the per-operative swabs. Full weight bearing was authorized on the 45th day. We observed no failure for heel localization. But in dorsal part of the ankle, we deplore 4 failures (on 9 cases). The rotation for ankle defects was rather important and the risk was squeezing the artery. We used 3 times the medial plantar flap as a cross foot. We observed 1 failure; the possibility of long pedicled flap (parallel legs), the innocuity for the donor site, the quality of the transferred skin are arguments for using that flap in a cross leg of rather small dimension. We successfully performed two more cross legs using this technique since that study. We think that the medial plantar flap is the best technique for heel reconstruction. The quality of the skin transferred is very able to make a secondary thickening reproducing exactly the consistence of the heel. The fiability of that flap is very high for the heel localisations (no failures on 21 cases).

Adolescent↗
PubMed1995

[Does laparoscopic treatment of abdominal infections generate bacteremias? Prospective study: 75 cases].

Laparoscopy is increasingly used in conditions complicated by peritonitis. A theoretical concern is that carbon dioxide pneumoperitoneum may increase bacteraemia. In a prospective study 90 patients were treated by laparoscopic appendicectomy. 30 of them had no histological abnormality; 30 had an acute appendicitis and 30 an acute peritonitis. 75 patients were eligible for the study. The treatment protocol (surgery-antibiotherapy) was the same for the 3 groups. All patients had blood cultures before, during and after insufflation of CO2 in the peritoneum, and bacterial examination of the operative site. Septic morbidity was evaluated for each patients. Positive bacterial culture from abdominal site are correlated with the pathologic findings. There were no positive blood cultures in the groups studied and no incidence in term of septic morbidity. This study suggests that laparoscopic treatment of septic abdominal diseases does not facilitate bacteriemias and does no affect septic morbidity.

Acute Disease↗
PubMed1994

Interpretation of the filtered 100- to 1000-Hz electroretinogram.

We examined the possibility that the 100- to 1000-Hz oscillatory potentials could represent the derivative version of the 1-1000-Hz electroretinogram. Corneal electroretinograms were recorded from rabbits by means of bandwidths of 1-1000 Hz, 10-1000 Hz, 30-1000 Hz and 100-1000 Hz (6 dB of attenuation). Derivatives of the 1- to 1000-Hz electroretinogram had a waveform similar to the 100- to 1000-Hz signals, but of larger amplitude (21.9% +/- 16.7% larger, n = 16). Similarly, integration of the 100- to 1000-Hz signal resulted in a waveform whose amplitude was 60% of the original 1- to 1000-Hz electroretinogram. Our results suggest that some aspect of the morphologic changes seen when the low-frequency cutoff of the recording bandwidth of the ERG is increased from 1 Hz to 100 Hz could be explained with a simple derivative model. The oscillatory potentials may be significant contributors to the morphogenesis of the 1- to 1000-Hz electroretinogram.

Animals↗
PubMed1994

The influence of social networks and social support on violence by persons with serious mental illness.

OBJECTIVE: The authors examined the relationship between violent acts and threats by persons with serious mental illness, the size and composition of their social networks, and characteristics of the social support they received. METHODS: A group of 169 respondents with serious mental illness and 59 of their significant others were interviewed using structured and semi-structured protocols to elicit data on demographic characteristics, clinical characteristics, characteristics of respondents' social networks and of the social support they received, and perceptions of threat within the social network. Data on acts and threats of violence by respondents over an 18-month period were collected from self-reports by respondents and significant others and from hospital and court records. RESULTS: Fifty-six respondents either threatened violence or committed a violent act during the study period. Respondents with a diagnosis of schizophrenia were more likely to commit violent acts but were not more likely to threaten violence than were respondents with other diagnoses. Respondents in larger networks, those with networks composed primarily of relatives, and those who lived with unrelated persons were more likely to threaten violence. Financial dependence on family was associated with more violent threats and acts. Respondents who perceived hostility from others were more likely to engage in violent threats and acts, and those with confused thinking were less likely to act or threaten violence. More than half of the targets of violence were respondents' relatives, particularly mothers living with a respondent. Respondents who were violent perceived their significant others as threatening but did not perceive themselves as being threatening in return. CONCLUSIONS: The interpersonal and social contexts of respondents and their perceptions of these contexts are important considerations in assessing risk for violence by persons with mental illness. Mothers who live with an adult offspring with schizophrenia may be at increased risk for being a target of violence. Violence by persons with psychiatric disorders may be linked to their perceptions and experience of being threatened by others.

Adult↗
PubMed1994

[Pathological fractures of the femoral neck in hemodialyzed patients. Apropos of 26 cases].

PURPOSE OF THE STUDY: This study is based on a retrospective analysis of 26 pathological fractures of the femoral neck in 19 chronic haemodialysis patients. The purpose of this study is to analyze the epidemiological and etiological factors of these fractures in relation to osteo-arthropathy of the dialyzed patient, as well as the results of various treatments, both curative and preventive. MATERIAL AND METHODS: 26 pathological fractures of the femoral neck appeared in 19 chronic haemodialysis patients, 11 men and 8 women, 6 patients presented bilateral fractures. The patient's average age at the time of the fracture was 61 years (27 to 82). The average duration of dialysis was 11 years with a minimum of 2 years and a maximum of 21 years. Hyper parathyroidism was found in 14 patients, aluminic intoxication in 6 and amyloidosis at the level of the coxo-femoral joint 18 times. Surgical treatment consisted of 6 osteosynthesis, 2 cephalic arthroplasties, 13 modular arthroplasties and 5 total hip arthroplasties. For each case, we studied the presence of necrosis of the femoral neck due to aluminic intoxication, osteoporosis due to hyperparathyroidism and also the presence of amyloidosis without aluminic intoxication. RESULTS: Cortisonic necrosis and porosis was found 4 times out of 26 cases, hyperparathyroidism once, aluminic osteomalacy 3 times and beta-2-microglobulin amyloid 18 times. Amyloidosis remains the most frequent etiological factor. All patients had been operated for median nerve compression in the carpal tunnel, usually 2.5 years before appearance of the pathological fracture. Non surgical treatment was used 5 times in undisplaced fractures without any sign of amyloidosis and was successful 3 times and unsuccessful twice necessitating a new operation by osteosynthesis. Out of 6 osteosynthesis performed for fractures either with little or no displacement we observed 4 failures, all of them in the cases with intra-osseous amyloidosis. Best results were obtained by arthroplasties. Modular arthroplasty has given us 11 long term excellent results in 11 of 13 cases. DISCUSSION: The analysis of etiological factors shows two very different groups. The first one consisted of 8 fractures without coxofemoral amyloidosis. The average duration of dialysis was 5 years, average age, 44 years. Etiology was 3 times aluminic osteomalacy, once the only factor found was osteoporosis and 4 times necrosis and porosis as a complication, not of haemodialysis but of renal transplantation with concomittant corticosteroid treatment. The second group consisted of 18 fractures with hip amyloidosis in 14 patients. The average age was 63.5 years, the dialysis duration was 11.5 years, the two extremes 5 and 21 years. Etiology was beta-2-microglobulin amylosis. The pathological fracture was due to the presence of voluminous subchondral amyloidosis geodes. Amyloidosis always associated with hyperparathyroidism and aluminic intoxication in one of 3 cases. Osteosynthesis gave good results only in cases presenting no intra-osseous amyloidosis. Modular arthroplasty has allowed us to obtain excellent long term functional results with simpler outcome. Total arthroplasty should be used only for evident acetabular involvement. CONCLUSION: Amyloidosis remains the etiological factor most frequently found in pathological fractures of the femoral neck in chronic haemodialysis patients. The study of the etiological factors is essential since they will guide us in the choice of the mode or treatment. It is totally licit to propose conservative treatment for non displaced fractures without osseous amylosis. In all other cases, prosthetic replacement is necessary and osteosynthesis contra-indicated. When the acetabulum is not altered a modular arthroplasty must be used. We do not recommend preventive surgical treatment for patients having a threatening geode of the femoral neck as all osteosynthesis realized on amyloidotic bone, even without any displacement, resulted

Adult↗