Search PubMed⌕ Search

Biomedical subjects

J Duparc

Publications and source records attributed to J Duparc.

At least 19 recordsLinked to original sources
PubMed1998

[Treatment of aseptic acetabular loosening by reconstruction combining bone graft and Müller ring. Actuarial analysis over 11 years].

INTRODUCTION: One reason for the limited longevity of total hip replacement is the progressive bone loss resulting from iterative loosenings of acetabular components. In the early 80's was developed an experience at our institution for revision surgery of aseptically failed cemented acetabular components using a Müller ring. At that time, this device was used in combination with structural grafts. This appeared to us to be the safest method to address severe acetabular destructions. We are now able to report long term results. MATERIAL AND METHODS: We carried out a retrospective study on 81 cemented acetabular revision arthroplasties performed at our institution between 1981 and 1991. In all cases, there was a segmental or an important cavitary roof defect. Reconstruction of the acetabulum was performed using a superior structural bone graft combined with a Müller ring. Results are given with a mean follow up of 8 years (5-14 years), except in the survivor analysis, in which all patients were included. RESULTS: There was 15 iterative aseptic loosenings of the acetabular component (in which 5 repeated revisions). Using iterative aseptic loosening of the acetabular component revised or not as an end point, the 10 year cumulative survival rate (CSR) was 0.72 +/- 0.14 and the 11 year CSR was 0.55 +/- 0.24. The position of the hip biomechanical center, the polyethylene thickness, or the type of the superior defect (segmental or cavitary) were not found to influence significantly roentgenographic results. DISCUSSION: Reconstruction of severely destroyed acetabuli using this method gave satisfactory results within the first decade. However, the hip function could not be reliably maintained over 10 years. Mechanical failures were related to resorption of weight bearing structural bone grafts. Aseptic iterative loosenings are often moderately symptomatic and yearly roentgenographic controls are necessary to detect late migrations. The lack of long term follow up may result in major bone loss, which can impair the conditions of iterative acetabular reconstructions.

Adult↗
PubMed1996

[Surgical treatment of radiation-induced lesions of the hip in adults].

The authors report their experience in the surgical management of lesions of the adult hip following radiotherapy. The diagnosis of a hip problem occurring after pelvic radiotherapy for malignant tumors is made by clinical and radiological examination. The problems include femoral head necrosis, necrosis and/or fracture of the acetabulum, or involvement of the entire hip joint (radiation coxopathy). Fractures of the femoral neck have been described in the literature, but are now very rare following the routine use of external shields as protection during irradiation. Post-irradiation lesions are often bilateral 21%. They appear after a variable latency period of two to twenty years and they progress remorselessly. A diagnosis of simple radio necrosis can only be made after using radio isotope bone scanning, MRI or CT to exclude malignant disease as acetabular metastasis, and radio-induced sarcomas. Hemiarthroplasty is often followed by collapse of the acetabulum and should no longer be used. The treatment generally practised nowadays is a Total Hip Replacement (THR). We report a retrospective study of 71 hips in 56 patients treated, between 1970 and 1982, by the use of conventional cemented components. In 49 hips this was followed by a 52% incidence of acetabular loosening resulting from the poor quality of the irradiated bone which had become necrotic and porotic. Between 1983 and 1990, we modified the technique by regularly using reinforcing the acetabulum with a metallic ring fixed by long screws, (as used in revision surgery for THR). Bone grafts were also used in 9 cases. We had a 12% incidence of loosening in 22 hips with a mean follow-up of 40 months. There were also two post-operative infection which need removal of the prostheses. This emphasizes the risk of infection in this type of surgery and is probably increased by the associated lesions of the soft tissues (lymphoedema, radiodermitis). The authors wish to stress the poor prognosis of radiation lesions of the hip which often occur in patients who have otherwise recovered from their pelvic tumour. These radiation lesions have to be recognised and treated in a specific way. Our experience and the reports in the literature suggest that the generally used conventional THR gives uncertain results, and therefore we propose a THR employing metallic reinforcement of the acetabulum with or without any necessary bone grafts. It is vital to warn the patients that the results may not be as excellent as with THR for other types of hip disorders. When there is severe destruction of the acetabulum the choice between a THR combined with massive bone allograft, and a Girdlestone hip resection must be very carefully discussed with the patient. This latter "salvage" procedure may in any case become necessary if there are local and otherwise unmanageable problems.

Adult↗
PubMed1995

[Radiographic and histologic observations of autoclaved and non autoclaved allografts in the distal femoral metaphysis in dogs].

PURPOSE OF THE STUDY: A canine experimental work was performed, to study osseointegration of cortico-cancellous bone allografts implanted in the lower femoral metaphysis. Particular attention was focused on observing the effects of autoclaving, used as a sterilizing method, on the osseointegration of bone allografts. MATERIAL AND METHODS: Eighteen dogs were operated on and three groups were formed according to the type of graft: the first group included 4 autoclaved autografts and one animal, in which no graft was implanted. The second group included 11 frozen allografts in which 4 had been autoclaved. The third group included 2 animals, who received autoclaved allografts and were sacrificed at 10 months. In the first two groups, all animals were treated with the same protocol: graft stabilization using a plate, and specimen harvest at 4 months after surgery. In the third group, graft stabilization was obtained by press-fit only, and no plate was used. RESULTS: Overall roentgenographic results were satisfactory, suggesting graft fusion with the host. Histological results were inferior to roentgenographic results, and showed graft resorption, but only some signs of bone formation at the periphery of the graft. DISCUSSION: Roentgenographic results appeared optimistic, when compared to histological results. This suggests that roentgenographic results should not be considered as a reliable criteria for graft osseointegration. Despite favorable experimental conditions (cortico-cancellous graft implanted in the metaphyseal region, in a loaded segment of the skeleton, optimum graft stabilization using lateral plating), histological results were poor. New bone formation was observed at the periphery of the graft, but the major part of the graft remained fibrous. No difference was found between autoclaved and non autoclaved allografts in this small series. CONCLUSION: These preliminary results suggest that autoclaving does not impair osseointegration of frozen bone allografts, which anyway remains incomplete.

Animals↗
PubMed1995

Total hip replacement in irradiated hips. A retrospective study of 71 cases.

We retrospectively reviewed 56 patients (71 hips) treated by total replacement for severe disability after pelvic irradiation. Symptoms were associated with various radiological lesions due to irradiation, including atraumatic femoral-neck fracture, osteonecrosis of the femoral head or of the acetabulum, and radiation osteitis of the whole pelvis. From 1970 to 1982 we used standard cemented components in 49 hips and had a high rate of acetabular loosening (52%) at a mean follow-up of 69 months. This was probably due to the mechanical insufficiency of irradiated periacetabular bone. From 1983 to 1990 we routinely used acetabular reinforcement rings. The rate of aseptic acetabular loosening in 22 hips at a mean follow-up of 40 months was 19%, but there were two septic loosenings emphasising the risk of infection in these patients. When total replacement is required for an irradiated hip, we recommend reinforcement of the acetabulum using a metallic ring, but there is still an increased risk of infection and in difficult cases such as severe acetabular destruction or soft-tissue or vascular injuries, a Girdlestone procedure may be indicated.

Adult↗
PubMed1993

[Autoclaved tumoral autografts. Apropos of 12 cases, 6 of which highly malignant].

Twelve patients presenting with a bone tumor were operated on using autoclaved bone autografts for reconstruction following carcinologic resection. According to the Enneking grading system, 6 were high malignancy tumors (3 osteosarcomas and 3 grade 2 chondrosarcomas), 4 were low grade tumors (1 paraosteal sarcoma, 1 chondrosarcoma, 1 secondary chondrosarcoma, 1 liposarcoma). One was a metastasis from a kidney tumor. The last patient had a femoral osteoid osteoma. Six local recurrences were responsible for 4 reoperations: 2 disarticulations and 2 iterative resections. With a 1-6 years range of follow-up (average follow-up 2.5 years), osseointegration of autoclaved grafts was studied. Fusion at the host/graft junction was roentgenographically observed. In three cases, proximal resorption of the humeral graft occurred. Five biopsies were obtained during reoperation after 1 year, which showed partial revascularization of autoclaved bone autografts. The authors conclude that autoclaved tumoral bone grafts, are reliable and discuss indications. They point out the main contraindication, represented by chemosensitive bone tumors, in which conservation of the removed tumor is necessary to quantify the response to chemotherapy.

Adolescent↗
PubMed1992

Results of 203 total hip replacements using a smooth, cementless femoral component.

We implanted 203 smooth-stemmed femoral components before January 1988. The femoral component used was anatomically shaped, fluted and made of titanium. Thirty-two hips were revised due to mid-thigh pain, and the femoral implant was found to be loose in all. In the 157 patients with a two-year follow-up, the Merle d'Aubigné and pain scores for completely cementless arthroplasties were similar to those for hybrid prostheses (cemented acetabular cup and cementless femoral stem). Of the 145 cases with two-year radiographic follow-up, 59 had extensive radiolucencies and 22 were unstable. The five-year cumulative survival rate was 77%. Implantation of this stem should be restricted to patients in whom cement fixation is contra-indicated.

Bone Cements↗
PubMed1991

Cementless fixation of hip prostheses in dogs.

Fixation of smooth cementless femoral prostheses was studied in 16 dogs which were killed 2, 3 and 4 months after operation. Rotational stability, examined by hand, was good in 9 cases and all stable prostheses could be extracted. Five out of 6 dogs, who did not bear weight after the operation, had a stable prosthesis compared with 4 out of 10 who walked early. Histology showed close bone apposition in 4, tight fibrous encapsulation in 4 and lack of tissue apposition in 8 which were loose. Bone remodelling in radiographs reflected the histological appearances; narrow radiolucent spaces were associated with dense well organised fibrous tissue, and wide radiolucent spaces with loose connective tissue. Prostheses with stems which fill the femoral canal should improve the fixation of smooth cementless prostheses.

Animals↗
PubMed1991

[Total hip prosthesis with screw rings. Results over 2 years of a series of 198 consecutive prostheses].

198 screw rings implanted before january 1988, 156 were combined with cementless femoral components, and 42 with cemented femoral components (hybrids). Fifteen cases, which were initially included in the first group, became hybrid at 2 years due to replacement of the femoral component by a cemented stem. 21 screw rings (11 per cent) were revised, and replaced with cemented polyethylene sockets. In 7 cases, acetabular reconstruction was required. Revision was justified by roentgenographic instability in only 6 cases. Four other implants were revised due to persistent postoperative pain, although there was no measurable migration on successive roentgenograms. In the 10 remaining cases, revision was initially justified by the femoral component: screw rings were found to be mobile and were replaced in the same time. Symptoms related to screw rings were easier to identify in hybrid arthroplasties, in which cemented femoral components were usually asymptomatic. Fourty five cases had a complete 2 year follow-up (34 were initially hybrid, 11 became hybrid due to revision of the femoral component). Twenty four patients complained of durable postoperative groin pain. In 18 of these cases, pain completely disappeared within the 18 first months. At 2 years, 28 patients had no pain. In 149 cases with complete 2 year roentgenographic follow-up, 126 implants had never migrated, 6 migrated early but stabilized within the first postoperative year, and 17 showed progressive migration over the first two postoperative years, in which 7 were finally revised. These results are inferior to those reported with cement. Some failures were explained by poor implantation techniques or by wrong indications. Other failures remained unexplained, thus justifying a reduction of their use in our institution.

Adult↗
PubMed1991

[Prostheses in recent and old complex injuries of the shoulder].

Eighty prostheses, including 46 humeral prostheses and 34 total ones, have been laid for complex injuries of the shoulder. In 56 cases, these were recent fractures, mainly of the head and tubercle of the humerus, in subject ages 65 in average. In 34 cases, the injuries were older and comprised malunion or epiphyseal necrosis. Five cases of subluxation and six of secondary displacement of the tubercles were noted. Pain was suppressed in most cases, but mobility was less satisfactory (37% exceeding 90 degrees active elevation). The humeral sealing evolved in a reassuring way, but a poorly evolutive glenoid rim was often observed. Finally, upper subluxation may occur during the evolution, which suggests the possibility of secondary ruptures in the rotator cuff.

Adult↗
PubMed1991

[Prevention of postoperative infections with cefotiam (Pansporine) in orthopedic surgery].

This prospective, randomized study was carried out in the Orthopaedic Traumatology service, Hôpital Bichat, from March 1987 to June 1989 in order to compare the efficacy of an antibiotic prophylaxis either with cefotiam in "flash" administration or with cefazolin in continued administration (48 hours). This study included 207 patients undergoing a total hip or knee-joint replacement. The both groups (89 patients with cefotiam, 118 patients with cefazolin) were comparable with regard to all criteria. The general and local evolution did not show statistical significant difference in the occurrence of complications in the both groups. No infectious complication occurred after the operation for the two groups. Then, cefotiam, in "flash" administration (2 g with the anesthetic induction) proves to be as effective as a conventional antibiotic prophylaxis with cefazolin in the prevention of infectious complications in orthopaedic surgery.

Bacterial Infections↗
PubMed1990

D-dimer and thrombin-antithrombin III complex levels uncorrelated with phlebographic findings in 11 total knee replacement patients.

D-dimer and thrombin-antithrombin III complex (TAT) were assayed in 11 patients at various times pre- and post-operatively in order to determine the possible value of these parameters in screening for thromboembolic complications. Phlebography revealed distal thrombosis in 6 of the 11 patients. The D-dimer level, already elevated before surgery, increased at day 1 and remained high at days 5 and 10. Two methods were used for the assays and showed strongly correlated results. The TAT level increased at day 1 and then progressively returned toward basal values. No difference was observed at any time between patients with or without thrombosis. The results in surgical patients undergoing knee replacement suggest that neither D-dimer nor TAT assays are valid screening procedures for post-operative DVT. Nevertheless, in view of the small number of patient studied, further work is required to confirm these results.

Adult↗
PubMed1989

Monocyte procoagulant activity and membrane-associated D dimer after knee replacement surgery.

We have recently shown that monocyte membrane-associated cross-linked fibrin derivatives (D dimer) can be evidenced by immunogold staining. Using this method, the procoagulant activity (PCA) expressed in vitro by endotoxin-stimulated monocytes has been found to correlate significantly with the number of D dimer-positive monocytes. The incidence of postoperative thrombosis in patients undergoing total knee replacement has been reported by Stulberg et al to be 57%. Since monocytes can play a role, via increased PCA, in the activation of intravascular coagulation, we sought to determine the level of monocyte PCA ex vivo after knee replacement surgery and its possible correlation with the number of D dimer-positive monocytes. Finally, we examined the possible link between these modifications and the occurrence of postoperative deep vein thrombosis (DVT). The PCA expressed by monocytes with or without suboptimal stimulation, the number of D dimer-positive monocytes and the plasma level of D dimer were measured pre- and post-operatively in 11 patients undergoing total knee replacement. Phlebography was performed on day 10 after surgery. A significant increase in the PCA of stimulated monocytes was observed on day 10 after surgery. Moreover, both the number of D dimer-positive monocytes and the plasma level of D dimer increased significantly post-operatively. The number of D dimer-positive monocytes correlated with both monocyte PCA and the plasma D dimer level. The relation between these parameters is discussed. However, neither monocyte PCA nor the number of D dimer-positive monocytes was found to correlate with the occurrence of deep vein thrombosis.

Adult↗
PubMed1989

[Surgical treatment of metastases of the acetabulum].

The lytic metastasis of the acetabulum are frequent, causing pathologic fractures, pain and disability. The authors analyze 42 acetabular metastases operated on between 1976 and 1986. Thirty-nine total hip replacements were made, 9 conventional arthroplasties for minor lesions, and 30 metallo-acrylic reconstructive surgery of the acetabulum combined in 8 cases to bone grafting of more extensive lesions. These arthroplasties allowed immediate weight-bearing. In three cases of very extensive acetabular destructions, hip resections were only possible. The complications were essentially: 3 early deaths, 2 acetabular loosening by tumor osteolysis, and one deep infection. Mean follow-up was 15 months. Results were assessed by pain and walking which are in the whole satisfactory in these patients with limited life expectancy. Surgical indications should be wide in disable patients. It is a palliative surgery aiming to improve the quality of life, giving the patient a functional autonomy.

Acetabulum↗
PubMed1989

[Bone diffusion of cefotiam in men].

A 2g single dose of cefotiam was given by rapid intravenous injection to 17 patients undergoing total hip replacement as a prophylaxis. The concentrations of the antibiotic in plasma and femoral head (cancellous bone, cortical bone and capsule) were measured at different time (40 to 250 minutes) following the injection of the drug. Evaluation was done by liquid chromatography. Mean antibiotic concentrations were 70.5 micrograms/ml, 41.4 micrograms/g, 16.9 micrograms/g and 8.1 micrograms/g respectively in plasma, capsule, cancellous and cortical bones. 240 minutes following the injection, mean concentrations of cefotiam were higher than 2.3 micrograms/ml in plasma and 1.8 micrograms/g in bone. Diffusion in cancellous bone is twofold high as in cortical bone and elimination half lif is higher in bone than in plasma (248.8 minutes versus 59.6 minutes in plasma). These results suggest that a 2g intravenous bolus injection of cefotiam given at the induction of anaesthesia should provide an effective prophylaxis during total hip replacement.

Absorption↗
PubMed1988

[Covering losses of cutaneous substance of the leg and foot using skin flaps. Apropos of 76 cases].

Between 1983 and 1987, 76 flap grafts were performed in the leg and foot. In general, 3 types of flap were used: --51 ipsilateral flaps, the majority of which were musculo-cutaneous flaps from the medial head of gastrocnemius (17 cases). --17 cross-leg flaps from the opposite limb, the majority of which were medial fascio-cutaneous flaps (13 cases). --8 free flaps, making use of microsurgical techniques. The indications for cross-leg flaps and free flaps have become more limited in favour of local regional pedicle flaps. The lower part of the leg and amputation stumps in the foot are easily covered by distal leg pedicle flaps and amputation stumps of the upper third of the leg can be covered by a flap of fascia lata with a distal pedicle based on the superolateral branches of the peri-articular plexus of the knee.

Cicatrix↗