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At least 289 records · Page 16Linked to original sources
PubMed2005

Simultaneous bilateral total hip arthroplasty with a cementless femoral stem.

Simultaneous bilateral total hip arthroplasty (THA) is an increasingly common procedure. Although use of a cementless stem can eliminate cement complications, some surgeons limit application of cementless THA because of concerns about early implant loosening. In this article, we report on 30 cementless THA cases (15 patients) followed up for a minimum of 2 years (range, 26-50 months). Despite 73% of femoral bone being type B or type C, all stems showed stable bone ingrowth fixation and no evidence of subsidence. Polyethylene wear rates (left, 0.154 mm/y; right, 0.114 mm/y) did not differ significantly. The excellent clinical results obtained with simultaneous bilateral cementless THA are comparable with those obtained with unilateral THA.

Aged↗
PubMed2005

[Study of change of size of the punctum before insertion and after extrusion of a punctal plug and selection of an appropriate plug for reinsertion].

PURPOSE: In cases when the reinsertion of punctal plugs is considered, enlargement of the punctum is often experienced and a larger punctal plug is sometimes required for reinsertion. We therefore investigated the change in the size of the punctum before insertion and after extrusion of a punctal plug and the selection of an appropriate punctal plug for reinsertion. SUBJECTS AND METHODS: There were 70 cases where punctal plugs were reinserted (37 eyes from 32 patients) because of extrusion of the plugs. A retrospective study was performed with regard to the change in the size of the punctum before insertion and after extrusion of the punctal plugs, and with regard to the type of plug reinserted. RESULTS: There were significant changes in the size of the punctum before insertion [0.70 +/- 0.09 (mean +/- standard deviation) mm] and after extrusion (0.78 +/- 0.07 mm) of the punctal plug (p < 0.001). In 22 cases of 23 cases which experienced extrusion of the 0.8 mm Eagle plug (EP; Eagle Vision), Punctal plugs (PP; FCI) of M size were selected for reinsertion, because there are no EPs larger than 0.8 mm available for reinsertion. DISCUSSION: After extrusion of the punctal plug, the punctum is likely to be enlarged, resulting in the need to select a larger punctal plug. Therefore, cases which experienced extrusion of an EP were likely to eventually have the EP replaced by a PP during follow-up treatment.

Aged↗
PubMed2005

Results with Kudo elbow prostheses in non-traumatic indications : a study of 36 cases.

With a mean follow-up of 62 months, we reviewed 13 Kudo type 4 and 23 Kudo type 5 elbow prostheses implanted for non-traumatic indications in 30 patients. Clinical results were assessed with the Mayo Clinic Performance Index (MCPI) taking into account pain, mobility, stability and daily activities. Postoperatively, pain disappeared or decreased, ulnar nerve dysfunction was improved and the functional status was significantly improved. The average range of motion increased by 7.8 degrees in extension and by 11.5 degrees in flexion; pronation and supination remained unchanged. Clinically, 89% of patients scored poorly on the MCPI preoperatively, whereas 61% had excellent or good scores postoperatively. Twenty-two patients out of 30 were satisfied. There were two early prosthetic dislocations, and prosthetic instability, assessed clinically, was found in 6 cases (17%). The rate of loosening was 28% (10/36) and seven elbows were revised. Metallosis, loosening and instability were significantly correlated. The survival rate of 82% at 54 months (SD = 7) is lower than that reported for non-constrained and semi-constrained prostheses in the literature.

Adult↗
PubMed2005

UHMWPE wear debris upregulates mononuclear cell proinflammatory gene expression in a novel murine model of intramedullary particle disease.

BACKGROUND: We examined the effects of ultra-high molecular weight polyethylene (UHMWPE) particles on mononuclear cell proinflammatory gene expression in a novel murine model. We hypothesized that mononuclear cell gene transcription of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1beta), interleukin-6 (IL-6) and macrophage chemoattractant protein-1 (MCP-1) would be upregulated by the addition of polyethylene particles in this murine intramedullary rod model. MATERIAL AND METHODS: The model involved a stainless steel Kirschner wire inserted retrograde with a line-to-line fit in bilateral femora of C57bl/6 mice. Additionally, the right femora were injected with 3 x 10(9) UHMWPE particles. Mononuclear marrow cells were isolated by bone marrow aspiration and Ficoll-Paque centrifugation at 2, 4 and 10 weeks post-surgery. Total RNA was isolated and real-time RT-PCR was performed to quantify gene expression. Histological specimens of explanted femora were also analyzed to track the changes in periprosthetic tissue. RESULTS: UHMWPE particles stimulated gene transcription in mononuclear cells when examined at 2, 4 and 10 weeks post-surgery, compared to the rod-only group. Relative levels of IL-1beta and MCP-1 mRNA increased in a linear fashion over the 10-week time-course. IL-6 mRNA showed increased expression which peaked at 4 weeks. TNF-alpha mRNA expression was variable and reached a minimum at 4 weeks. The addition of UHMWPE particles stimulated ingress of macrophages and multinuclear cells of macrophage origin to the bone-implant interface. INTERPRETATION: In this model, a single bolus of UHMWPE particles had a long-term effect on gene transcription in mononuclear cells which perpetuated a chronic inflammatory state. This murine model of intramedullary particle-induced inflammation simulates periprosthetic events associated with implant wear in humans, and may contribute to a more mechanistic understanding of wear-debris associated prosthesis failure.

Animals↗
PubMed2005

Total knee arthroplasty with conventional or navigated technique: comparison of the learning curves in a community hospital.

We performed a comparative study of the short-term radiological and clinical results after implantation of an unconstrained TKA with preservation of the posterior cruciate ligament with a conventional (50 cases--group A) or navigated (50 cases--group B) technique. The primary criterion was the postoperative leg coronal alignment measured on 3-month postoperative anteroposterior long-leg radiographs by the HKA angle: the expected alignment was 180 degrees +/- 3 degrees. The mean post-operative HKA angle was 180 degrees +/- 3 degrees in group A and 180 degrees +/- 1 degrees in group B (p = 0.15). Thirty-four cases in group A and all 50 cases in group B were in the desired range (p < 0.001). The navigated system used in this study allowed for a significantly better alignment accuracy than the conventional implantation technique. Acceptable routine implantation was achieved during the time of the study (first 50 cases). We can thus hypothesise that the learning curve of the navigated technique used is not any longer than the learning curve of a conventional implantation technique.

Aged↗
PubMed2005

Device-related reoperations after laparoscopic adjustable gastric banding.

Laparoscopic adjustable gastric banding (LAGB) is considered a relatively safe weight loss procedure with low morbidity. When complications occur, obstruction, erosion, and port malfunction require reoperation. We retrospectively reviewed our experience with 270 consecutive patients who underwent LAGB. Device-related reoperations were performed in 26 (10%) patients. Reoperations were related to the band in 13, to port/tubing in 11, and related to both in 2 patients. Of the 15 band-related problems, it was removed in 5 (2%): slippage (3), intra-abdominal abscess (1), and during emergent operation for bleeding duodenal ulcer (1). Revision or immediate replacement was performed in 10 (4%): slippage (5), obstruction (4), and leak from the reservoir (1). Port/tubing problems were the reason for reoperations in 13 (5%): infection (5), crack at tubing-port connection (6), and port rotation (2). Port removal for infection was followed later by port replacement (average 9 months). Overall, slippage occurred in 8 (3%), obstruction in 4 (1.5%), leak from reservoir in 7 (3%), and infection in 5 (2%) patients. Fifteen device-related problems occurred during our first 100 cases and 12 subsequently (P = 0.057). Permanent LapBand loss was only 5 per cent, leading to overall rate of 95 per cent of LapBand preservation as a restrictive device.

Gastroplasty↗
PubMed2006

Results of total knee replacement using a cemented stemmed prosthesis.

OBJECTIVE: To present the results of total knee replacement at the King Abdul-Aziz University Hospital in Jeddah, Kingdom of Saudi Arabia (KSA). METHODS: The medical records of 205 patients who received 309 prostheses was reviewed. The study took place at King Abdul-Aziz University Hospital, Jeddah, KSA between May 1989 and August 2005, where patients were either examined in the outpatient clinic or interviewed on the phone. Seventeen patients (22 prostheses) were lost for follow up. The scores were registered according to the Knee Society Clinical Rating System. RESULTS: There was a significant improvement in all-functional scores postoperatively in the first year, which continues without significant change throughout the follow up period. Symptomatic deep vein thrombosis was observed in 5 patients, 3 of them had pulmonary embolism, which was fatal in 2 cases. Early deep infection occurred in 3 cases. Superficial wound infection was seen in one patient. One patient suffered peroneal nerve palsy, while 4 patients had aseptic loosening of the femoral implant. One patient had rupture of the patellar tendon. Metal breakage was observed once and one patient is diagnosed to have polyethylene wear. In the early phase, when a prosthesis type without dislocation protection was used, 7 dislocations occurred. This type was not used anymore and no such complication was observed. CONCLUSION: Total knee replacement relieves pain and improves quality of life significantly. The observed complications compare well with the results reported in the literature.

Arthroplasty, Replacement, Knee↗
PubMed1995

An 11-year reevaluation of resin-bonded fixed partial dentures.

Clinical success of resin-bonded fixed partial dentures is primarily dependent on their long-term retention. Retention rates of resin-bonded prostheses placed in 66 patients treated by three dentists in private practice were evaluated in the present study. Seventy-seven resin-bonded fixed partial dentures were followed over a period of 1 year to 11 years. Thirty (39%) became dislodged, but nine were successfully rebonded; thus there were 21 failures (27%). Prosthesis location and operator expertise minimally influenced the longevity of these restorations, but the luting agents tested in this sample had a profound impact on retention. Debonding rates were excessive for some materials tested, whereas other agents proved to be predictable. Modifications in preparation design that enhanced resistance form were also likely contributors to improved retention rates.

Dental Bonding↗
PubMed1995

[Artificial urinary sphincter].

The artificial urinary sphincter is a totally implantable hydraulic prosthesis designed to restore continence without inducing dysuria. It is composed of 3 silicone elastomer elements: a periurethral or pericervical cuff, a pressure regulating reservoir balloon inserted in the retropubic space, and a pump situated in the scrotum or labia majora. The prosthesis is filled with a liquid containing a contrast agent. Pressure on the pump allows passage of liquid from the cuff towards the balloon and allows micturition. After 3 to 4 minutes, the liquid is automatically transferred from the balloon to the cuff to restore continence. The artificial sphincter is currently a very effective therapeutic solution in cases of severe urinary incontinence with 3 main indications: persistent incontinence after prostatic surgery, recurrent incontinence in women due to sphincter insufficiency, and certain forms of neurogenic incontinence. The Pitié-Salpêtrière Urology Department's experience currently consists of 200 implantations performed over the last 10 years. The overall success rate varies from 80 to 90% according to sex and the aetiology of incontinence, in patients in whom the sphincter remains in place. In fact, there is a risk of explantation due to erosion of the tissues by the cuff or infection, but this risk is less than 15%. The risk of prosthesis failure is about 20%, but after correction of the defective element, cure is achieved in almost every case. Analysis of the results in the first 120 patients with the two most frequent aetiologies and with at least three years' follow-up (range: 3 to 10 years) reveals: in a series of 75 men, treated for severe incontinence persisting more than one year after surgery for benign prostatic hyperplasia, the explantation rate was 15% and, in the patients in whom the sphincter remained in place, complete cure was obtained in 73% of cases without any incontinence, while 17% of patients suffered from minimal incontinence, not requiring protection, 7% had moderate incontinence requiring protection and 3% were considered to be failures. The revision rate for technical failure was 24%. In a series of 45 women with recurrent incontinence after surgery, due to sphincter insufficiency, the explanation rate was 13% and, in women in whom the sphincter remained in place, complete success was obtain in 78% of cases without any incontinence, while 17% suffered from minimal incontinence, usually not requiring protection, 5% require protection, with no failures and a revision rate for technical failure of 24%.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1996

Initial stability of a modular uncemented, porous-coated femoral stem: a mechanical study.

A versatile modular hip system was used to evaluate the initial stability of a cementless femoral stem in anatomically consistent composite bones. Four implant bone configurations of varying proximal and distal fit/fill were tested. The implanted femurs were tested on an Instron 1331 materials testing machine in neutral loading and flexion loading; both translational micromotions and rotations of the implant relative to the bone were recorded on all three axes of motion, accounting for all 6 degrees of freedom of joint motion. Implants were then sectioned, and both endosteal canal fit and intramedullary canal fill were measured. Results indicate that (1) loading the implant in flexion by out-of-plane forces significantly increases both relative translation and rotation at the interface, (2) increasing the proximal fit reduces implant rotation about its longitudinal axis in flexion loading and (3) increasing the distal canal fit and fill increases prosthesis rotation about its longitudinal axis in flexion loading. These results indicate that the femoral stem is more unstable in out-of-plane loading, such as during stair climbing, and that increasing the proximal fit may enhance the initial rotational stability of an uncemented femoral stem.

Biomechanical Phenomena↗
PubMed1997

[Modularity of prostheses].

Modularity allows a large choice of implants, like the use of cementless acetabular cups inducing bone ingrowth. The length and direction of the neck may also be adapted to be new joint. Risks of modularity are: implant dissociation, restriction of joint mobility, and especially augmentation of metal debris as a potential source of polyethylene wear. It is then critical to play attention to implant design, material choice and planning of the arthroplasty.

Hip Prosthesis↗
PubMedDate not supplied

[Crystalline structure of endoprosthetic UHMWPE in relation to sterilization and mechanical processing].

We analysed the changes in crystallinity in sterilized and machined UHMWPE products used in the manufacture of total joint components. For this purpose, so-called DC measurements of absolute crystallinity and infrared spectroscopy for determining the relevant crystallinity were carried out. The DSC measurements are based on a further development of differential thermo-analysis (DTA), and a comparison of the melting enthalpy of an unknown material in comparison with known material. The results show particularly high values for gamma sterilized products, and the lowest values, i.e. the least brittleness, after sterilization with ETO. The crystallinity of the original material was 55%, that after gamma sterilized 56.5%, and after steam autoclaving 57.9%; after gamma sterilized in argon 56%, and after ETO sterilized 57.7%. During the period prior to the manufacture of the end product, a wide range of values is determinable. The average crystallinity of the end products varies between 55.4% and 61.6%. Among other things, changes in crystallinity during storage and after implantation must be taken into account. To summarize, we recommended ethylene oxide sterilization, after which the best values of crystallinity were seen in both semi-finished and finished products (prostheses).

Biocompatible Materials↗
PubMed1998

Impact of prosthesis-patient mismatch on hemodynamic and symptomatic status, morbidity and mortality after aortic valve replacement with a bioprosthetic heart valve.

BACKGROUND AND AIMS OF THE STUDY: Previous studies have shown that the effective orifice area of an aortic prosthetic valve may be too small in relation to the patient's body surface area, resulting in abnormally high gradients. The consequences of this condition, termed prosthesis-patient mismatch, have not been fully studied. The study objective was to determine if the condition has a detrimental effect on symptomatic and hemodynamic status, morbidity and mortality of patients undergoing aortic valve replacement. METHODS: A cohort of 392 patients was prospectively followed for up to seven years after implantation of a Medtronic Intact bioprosthesis. Doppler echocardiography was performed annually in 72 patients. Based on previous studies, presence of mismatch was defined as an indexed valve area < or = 0.85 cm2/m2. RESULTS: Mismatch was associated with less postoperative improvement of NYHA functional class (p < 0.009) independently of other predictors, such as age and preoperative functional class, but had no significant impact on patient survival (mismatch: 75 +/- 4%, no mismatch: 79 +/- 3%; p = 0.59) and valve-related morbidity up to seven years. Cardiac index was similar in patients with and without mismatch up to three years after operation but decreased significantly thereafter only in patients with mismatch (-0.54 +/- 0.32 versus -0.17 +/- 0.49 l/min/m2; p = 0.04). Likewise, the mean transprosthetic gradient, which was higher at one year after operation in patients with mismatch (22 +/- 8 versus 15 +/- 7 mmHg), increased significantly (+6 +/- 6 versus +1 +/- 1 mmHg; p = 0.008) only in this group during follow up. CONCLUSIONS: Patients with mismatch have less symptomatic improvement and worse hemodynamics that continue to deteriorate with time. However, medium-term prognosis (up to seven years) is relatively good. Further studies are necessary to determine the longer-term effects of mismatch on morbidity and mortality.

Aged↗
PubMed1998

[Treatment of fractures of the orbital floor: reconstruction using Teflon sheets. Analysis of the results after 5 years].

We report our experience with fractures of the orbital floor over the past five years, reporting 80 cases. Different anatomic and clinical forms were defined, particularly trap-door fractures. After a clinical and computed tomography study, we recommend treatment with Teflon implants. Results obtained were analyzed and compared with other series in the literature.

Accidents, Traffic↗