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At least 451 records · Page 25Linked to original sources
PubMed1985

Complications of the Angelchik antireflux prosthesis. A community experience.

The use of the Angelchik antireflux prosthesis has increased rapidly in our community since its introduction in 1979. Our experience with two patients who had serious complications associated with this prosthesis led us to review all 76 patients in our community who had undergone implantation of the device. Complications developed in 20 patients after placement of the prosthesis, and 12 of them required subsequent laparotomy for removal of the prosthesis. The complications observed were persistent dysphagia, late-onset dysphagia, transient dysphagia, persistent vomiting, esophageal obstruction, early gas bloat syndrome, gastric erosion, slippage of the prosthesis over the gastric fundus, disruption of the prosthesis, and migration of the prosthesis. Because of the frequency of potentially serious complications, we cannot recommend its use in the surgical treatment of esophageal reflux.

Adult↗
PubMed1982

Treating GI reflux with a prosthesis.

The antireflux prosthesis has had excellent results and simplified surgical treatment of this condition. At about 20 minutes, actual operative time is considerably reduced compared with traditional hiatal hernia repairs. From 1973 to 1982, 174 patients underwent surgery with a specified follow-up series of UGI radiological studies. There were no mortalities related to the prosthesis. Three patients had the prosthesis removed. Complications related to the prosthesis included its displacement in one patient in whom the knot slipped. The prosthesis was replaced with excellent results. In one instance, a spleen laceration necessitated a splenectomy. Fifty patients experienced transient dysphagia for two to six weeks or longer but with no problems after the dysphagia subsided. Twenty-three were determined through x-ray to have had the prosthesis migrate above the diaphragm due to a large hiatus. In all of these 23 patients, the prosthesis remained at the gastroesophageal junction, and they remained asymptomatic. Perioperative nursing care and teaching closely follows that of traditional hiatal hernia repair with a shorter and less traumatic recovery.

Gastroesophageal Reflux↗
PubMed2000

Lower limb prosthesis utilisation by elderly amputees.

The goal of prosthetic rehabilitation is to compensate for the loss of a limb by amputation by, in the case of a lower limb, encouraging walking, and to achieve the same level of autonomy as prior to the amputation. However, because of difficulties walking, elderly amputees may use their prosthesis to a greater or lesser degree or simply stop using it during the rehabilitation period. The objective of this research was to study factors such as physical and mental health, rehabilitation, physical independence and satisfaction with the prosthesis to understand why amputees use their prosthesis or not. The sample was composed of 65 unilateral vascular amputees 60 years old or over living at home. The information was collected from medical records, by telephone interview and by mail questionnaire. Prosthesis use was measured by a questionnaire on amputee activities developed by Day (1981). Eighty-one per cent (81%) of the subjects wore their prosthesis every day and 89% of this group wore it 6 hours or more per day. Less use of the prosthesis was significantly related to age, female gender, possession of a wheelchair, level of physical disability, cognitive impairment, poorer self-perceived health and the amputee's dissatisfaction. A multiple regression analysis showed that satisfaction, not possessing a wheelchair and cognitive integrity explained 46% of the variance in prosthesis use.

Age Distribution↗
PubMed1999

Radiotransparency of the triglyceride mammary prosthesis: a quantitative analysis with mastectomy specimens.

Breast cancer is the most frequent malignant tumor in women. It is estimated that 10 percent of women will present with a breast cancer during their lives. It is well known that mammography is the best technique for the early diagnosis of nonpalpable tumors, thus improving life expectancy. However, mammary prostheses may hide between 23 and 82 percent of the normal mammary tissue in mammography, and thus may delay the diagnosis of malignant mammary tumors, making prognosis worse. To solve this problem, oil-filled prostheses have been developed. In this study, 14 mastectomy specimens were used. Mammograms of the tissue pieces alone and also mammograms of the tissue pieces covering a 270-cc Trilucent prosthesis were used to verify whether the prosthesis allows observation of malignant signs in mammography. Mammograms were evaluated by an independent experienced radiologist. The following variables were studied: number of mammograms necessary to examine each specimen; kilovoltage and milliamperage necessary for each mammogram; number of microcalcification groups (malignant); number of macroscopic calcifications (benign); and rarefaction areas that were suspected for malignancy. All of these variables were measured for both mammograms for which the mastectomy specimens were covering and those for which the specimens were not covering the prothesis. Finally, the kilovoltage and milliamperage increases necessary to visualize the mammograms with mastectomy specimens covering the prosthesis were determined. Statistical analysis of the results obtained was performed. There were no significant differences in the number of mammograms (p = 0.391), the number of microcalcifications (p = 0.890), the number of macrocalcifications (p = 0.239), and finally in the presence of rarefaction areas (p = 1.000) observed in the mammograms in specimens either covering or not covering the prosthesis. However, there were significant differences (p < 0.001) between the kilovoltage and milliamperage applied to carry out the mammograms of specimens with and without the prosthesis. Thus, Trilucent prostheses allow visualization of the microscopic and macroscopic calcifications as well as rarefaction areas in mammograms. However, these mammograms required a higher kilovoltage and milliamperage compared with specimens not covering the prosthesis. To explore the whole gland, it might be necessary to perform two series of mammograms: one to detect the area shadowed by the prosthesis and one to observe the rest of the peripheral gland.

Breast Implants↗
PubMed2007

Allograft-prosthesis composites after bone tumor resection at the proximal tibia.

The survival of irradiated allograft-prosthesis composites at the proximal tibia is mostly unknown. However, allograft-prosthesis composites have proved beneficial at other reconstruction sites. We presumed allograft-prosthesis composites at the proximal tibia would improve survival and facilitate reattachment of the extensor mechanism compared with that of conventional (megaprostheses) reconstructions. We retrospectively reviewed 26 patients who underwent resection of proximal tibia tumors followed by reconstruction with allo-graft-prosthesis composites. Patients received Guepar massive custom-made fully constrained prostheses. Allografts were sterilized with gamma radiation, and the stems were cemented into the allograft and host bone. The minimum followup was 6 months (median, 128 months; range, 6-195 months). Fourteen patients had one or more components removed. The median allograft-prosthesis composite survival was 102 months (95% confidence interval, 64.2-infinity). Of the 26 allografts, seven fractured, six showed signs of partial resorption, and six had infections develop. Seven allografts showed signs of fusion with the host bone. Six extensor mechanism reconstructions failed. Allograft-prosthesis composites sterilized by gamma radiation yielded poor results for proximal tibial reconstruction as complications and failures were common. We do not recommend irradiated allograft-prosthesis composites for proximal tibia reconstruction.

Adolescent↗
PubMedDate not supplied

Early experience with the GORE-TEX polytetrafluoroethylene anterior cruciate ligament prosthesis.

A prospective study of 41 patients with acute and chronic ACL deficiency underwent reconstruction with the GORE-TEX polytetrafluoroethylene (PTFE) ACL prosthesis beginning in November 1983. Thirty-nine patients who were at least 2 years from their surgical procedure were available for follow-up evaluation, which included subjective questionnaire, clinical examination, and instrumented ligamentous laxity tests. Eight patients had an acute injury to the ACL and 31 patients had chronic ACL insufficiency for which reconstruction was performed. Thirty-four patients had satisfactory results, allowing full return to activity with no appreciable symptomatology. Of the remaining five patients, four had a complete rupture of the prosthesis. The average knee arthrometric measurement improved from a 5.4 mm left/right difference preoperatively to a 2.0 mm left/right difference at 2 year followup. Nine patients had postoperative complications of one or more atraumatic episodes of a sterile effusion. Six patients had recurrent effusions; in five, arthroscopy revealed partial tears of less than one-third of the prosthesis. Three patients who had recurrent effusions had PTFE particles in their synovial biopsies. One patient had an immediate postoperative infection and to data has had salvage of the prosthesis and currently has a stable knee with full return to activities. Based on the early results of this study, the GORE-TEX PTFE ACL prosthesis provided a satisfactory method of reconstruction for ACL deficient knees. Based on the evaluation used, 87% of the patients had satisfactory results. Problems associated with use of this prosthesis include partial or complete tears of the prosthesis and sterile effusions, possibly due to synovial irritation from the PTFE particles.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed2002

Change in levator veli palatini muscle activity for patients with cleft palate in association with placement of a speech-aid prosthesis.

OBJECTIVE: The purpose of this study was to examine whether a speech-aid prosthesis normalizes the activity of the levator veli palatini muscle for patients with cleft palate who exhibit velopharyngeal incompetence. DESIGN: Each subject was instructed to produce repetitions of /mu/, /u/, /pu/, /su/, and /tsu/ and to blow with maximum possible effort. Electromyographic (EMG) activity of the levator veli palatini muscle was recorded with and without a hybrid speech-aid prosthesis in place. PARTICIPANTS: The participants were five patients with repaired cleft palate who were routinely wearing a hybrid speech-aid prosthesis. RESULTS: With the prosthesis in place, the mean value of levator activity changed positively in relation to oral air-pressure change during blowing. Differences in levator activity in relation to speech samples were similar to those in normal speakers. With the prosthesis in place, levator activity for speech tasks was less than 50% of the maximum levator activity for all subjects. The findings were similar to those reported previously for normal speakers. CONCLUSION: Placement of the prosthesis changed EMG activity levels of the levator veli palatini muscle to levels that are similar to normal speakers. It is possible that, with the increase in the differential levator activity between speech and a maximum force task, the velopharyngeal mechanism has a greater reserve capacity to maintain velopharyngeal closure compared with the no-prosthesis condition.

Adolescent↗
PubMed1996

A comparison of energy expenditure by a high level trans-femoral amputee using the Intelligent Prosthesis and conventionally damped prosthetic limbs.

Comparisons were made between the Intelligent Prosthesis (IP), Mauch and pneumatic swing phase control damping systems on the same prosthesis worn by a high level trans-femoral amputee. Speeds self selected by corridor walking (4.4-5.5 kmh-1) proved not to be sustainable for treadmill walking. Comfortable speeds were attained when the subject walked on a treadmill at 2.0, 2.6 and 3.2 kmh-1 in two tests for each prosthesis type. Oxygen uptake (VO2), cadence and heart rate were measured over 5 minute walks interspersed with rest periods. Spearman's correlation was used to test for differences between prosthesis types at each speed. At the two slower speeds no significant difference was found, but at the higher speed of 3.2 kmh-1, the IP was associated with a significantly lower VO2 (p < 0.05). A two way analysis of variance with replication (ANOVA) demonstrated a significant difference between VO2 for different limb types (p = 0.015). A square law function was fitted to the mean VO2 for each prosthesis type by the method of least squares regression. ANOVA demonstrated a significant difference between velocity coefficients for the different prosthesis types (p < 0.05). Cadence was almost constant during the period of each walk, varying by 1 step min-1 at most. However the test-retest differences in cadence were considerable. It is concluded that there was little difference in energy expenditure between prosthesis types at slower speeds, but at higher speeds (==> 3.2km h-1) the IP gave a lower oxygen uptake by about 10%.

Adult↗
PubMed1999

The ultra-low resistance Groningen voice prosthesis: aerodynamic properties.

Post-laryngectomy voice rehabilitation using the low resistance (LR) Groningen voice prosthesis has over the past years provided good voice and speech results. The valve part of the prosthesis is largely responsible for the airflow resistance of the prosthesis. This study was performed to evaluate if by modifying the valve part of the LR Groningen prosthesis a lower airflow resistance in vitro could be achieved. Several prototypes with modified valves were tested. Based on the aerodynamic measurements the prosthesis with a single slit of 200 degrees in the 'hat' of the esophageal flange was selected for further evaluation and named the ultra-low resistance (ULR) Groningen voice prosthesis. Aerodynamic measurements were performed and showed the airflow resistance of the ULR Groningen voice prosthesis to be significantly lower than the resistance of the LR Groningen and the Provox voice prostheses.

Equipment Design↗
PubMedDate not supplied

[The use of synthetic prosthesis in the treatment of hernia].

The authors report their experience on synthetic prosthesis used in 36 patients with abdominal hernias. Thirty six cases of incisional hernias have been analyzed by Institute of General Surgery of Messina University from 1992 to 1998. Among the 33 cases with median parietal defect, in 7 cases concerning great incisional hernias group a PTEF-e prosthesis, which was positioned in an intraperitoneal site, was employed. In 21 cases of medium size incisional hernias they used a polypropylene prosthesis, which was positioned in an intraparietal or preperitoneal site. In 5 cases of small size incisional hernias, polypropylene prosthesis was placed in a superfascial site. In the 3 cases of medium size lateral laparocele++, polypropylene prosthesis was positioned in a intraparietal site. There was no operative mortality. Among postoperative complications, 4 seromas, 1 parietal and 1 subcutaneous haematoma and 2 haematomas in retroperitoneal site appeared. Clinical-instrumental controls, which have continued until two or three years after the operation were performed which pointed out a recurrence in just one case where the prosthesis was positioned in a superfascial site. To conclude, we consider that nowadays the use of synthetic prosthesis lets us face and solve problems concerning surgical treatment of incisional hernias with confidence.

Adult↗
PubMed2004

[Failure rate and revision surgery in ossiculoplasty with Kurz titanium prosthesis].

UNLABELLED: Despite its excellent biocompatibility, failures and in particular extrusion of the prosthesis have been described in ossiculoplasty with titanium prosthesis. OBJECTIVE: Report our experience with revision ossicular recontruction in ossiculoplasty with Kurz prosthesis. Identify causes of failure in ossiculoplasty using the titanium prosthesis. MATERIAL AND METHODS: Retrospective chart reviews were performed for 110 patients who had undergone titanium ossicular implants between November 1998 and 2002. All patients had undergone ossiculoplasty using titanium middle ear implants. Patients were divided into 2 groups: in group 1 patients underwent revision ossiculoplasty; in group 2 patients had a successful surgery at first stage. Anatomic and functional results have been studied in these two groups. Causes of failures were analysed. RESULTS: The overall failure rate was 20% (22/110). Twenty patients underwent revision ossiculoplasty. Nine primary failures were attributable to a short implant. Two extrusions were observed. At long term billow-up, the functional gain between the primary and revision ossiculoplasty was comparable. CONCLUSION: Revision ossiculoplasty is worthwhile for those patients who have failure of the titanium prosthesis in ossiculoplasty. A large cartilage graft interposition is necessary to prevent extrusion. The overall luxation rate observed in our series was mainly due to a too short prosthesis and we recommend now a reconstruction with longer prosthesis.

Adult↗
PubMed1984

Design and evaluation of a prosthesis control system based on the concept of extended physiological proprioception.

This paper describes the design and evaluation of an experimental prosthesis-control system based on the concept of extended physiological proprioception (EPP). It was originally hypothesized that EPP control effected by residual shoulder motion could be effectively applied in multifunctional prostheses for shoulder disarticulation amputees. The experimental system developed for this study utilized a force-driven control scheme and a shoulder motion transduction system in which direct cable linkages to the prosthesis components were used to implement EPP position-servo relationships between shoulder elevation-depression and prosthesis elbow flexion, and between shoulder protraction-retraction and prosthesis wrist rotation. The results of experiments performed with this prosthesis (and with an experimental velocity-controlled prosthesis implemented for comparison purposes) clearly demonstrated the superior performance provided by EPP control of prosthesis function.

Arm↗
PubMed2005

[Periprosthetic bone loss after total hip endoprosthesis. Dependence on the type of prosthesis and preoperative bone configuration].

The changes of the periprosthetic bone density were examined with DEXA in 81 patients over a period of 1 year after implantation of cementless total hip endoprosthesis. Four types of endoprostheses (Vision 2000/Duraloc, ALPHA-Fit/ALPHA-Lock Plus, CLS/Allofit, Mayo/Trilogy) were implanted. Information on the changes of the periprosthetic bone density depending on the type of the prosthesis and the bony situation at the femur before operation was expected from these measurements. In all types of stems the strongest reduction of the bone density was found in the region of the calcar femoris, and the smallest changes were found distally and medially of the tip of the prostheses. In the prosthesis with shorter stem the change of the bone density was altogether clearly lower than in prostheses with longer stem. With increasing size of the prosthesis with proximally porous coating made from cobalt-chrome alloy, proximal atrophy was observed more frequently, whilst in the prosthesis made from titanium alloy with completely rough-blasted surface the distal hypertrophy increased. A low preoperative corticalis-bone marrow index strengthened the proximal atrophy in proximally porously coated prosthesis made from cobalt-chrome alloy and led in the prosthesis with completely rough-blasted surface more often to distal hypertrophy of the bone.

Absorptiometry, Photon↗
PubMed2005

Doppler echocardiography of 119 normal-functioning St Jude Medical mitral valve prostheses: a comprehensive assessment including time-velocity integral ratio and prosthesis performance index.

The purpose of this study was to provide, in a large number of patients, comprehensive Doppler echocardiographic assessment of normal St Jude Medical mitral valve prosthesis function using Doppler-derived hemodynamic variables, including the mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio and prosthesis performance index. The pressure half-time was less than 130 milliseconds in all patients, and all but one patient had either a peak early mitral diastolic velocity of 2 m/s or less or a mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio of less than 2.2. There was a significant (P < .001) negative correlation between the prosthesis performance index and prosthesis size. This negative correlation suggests that there is more efficient use of the in vitro geometric orifice area with smaller prostheses.

Adolescent↗
PubMed2004

Replacement of a tracheal defect with a tissue-engineered prosthesis: early results from animal experiments.

OBJECTIVES: The major problems in the development of tracheal prosthesis are anastomotic dehiscence and stenosis, caused by poor epithelialization of the prosthetic graft. We developed a novel tracheal prosthesis with viable mucosa transplanted from the oral cavity and reported excellent long-term results after thoracic tracheal replacements in dogs. In the current study, we used tissue-engineering techniques to construct a mucosal prosthetic lining from skin cells and evaluated its usefulness in tracheal replacement. METHODS: Abdominal skin patches (5 x 10 cm) were harvested from 10 adult mongrel dogs. The epithelial cells were separated, cultured in vitro for 4 weeks, and then seeded onto a porous polylactic glycolic acid scaffold (6 x 8 cm) to construct a lining mucosa. This was then mounted onto the prosthesis framework, made with polypropylene mesh reinforced with polypropylene rings. The mucosa-lined prosthesis was wrapped with the greater omentum of the same dog and placed in the peritoneal cavity for 1 week. Complete surgical resection and replacement of a thoracic tracheal segment (5 cm in length, just above the carina) was then performed using the prosthesis. RESULTS: The animals regained full activity and survived with normal activity. Bronchoscopy at 1 week and at 1 and 2 months revealed no stenosis in the anastomosis. CONCLUSIONS: This highly biocompatible tracheal prosthesis could prove useful for the reconstruction of large, circumferential tracheal defects.

Anastomosis, Surgical↗
PubMed2005

[Recent fractures of the radial head associated with elbow instability treated with floating Judet prosthesis].

PURPOSE OF THE STUDY: Fracture of the radial head associated with elbow instability is infrequent. We report a retrospective series of floating Judet prostheses implanted for comminutive fractures of the radial head associated with elbow laxity caused either by dislocation or rupture of the medial collateral ligaments. MATERIAL AND METHODS: The series included ten patients who underwent surgery from October 1996 to September 2002 at the Amiens University Hospital. The indication for radial head prosthesis was established in the emergency setting for fracture unamendable by osteosyntheis and elbow laxity. Mean age was 48.2 years (25-69). All patients were seen at mean follow-up of 31.7 months (18-48). According to the Mason classification as modified by Johnson, all patients had type 4 fracture. A Judet radial head prosthesis with a floating metallic cup was implanted in all patients. An investigator other than the operators evaluated outcome using the Mayo Clinic criteria. RESULTS: Joint motion as measured by goniometry was: mean flexion 121degrees (90-140 degrees), mean extension deficit 20 degrees (5-60 degrees), mean pronation 45 degrees (0-85 degrees), mean supination 42.5 degrees (0-90 degrees). The Mayo clinic score was excellent in 3, good in 2, fair in 3, and poor in 2 (prosthesis dislocation in one and hung prosthesis requiring removal in one). Four patients developed periarticular ossifications compromising the final result. DISCUSSION: The floating Judet prosthesis allows optimal adaptation of the implant to anatomy and function. For us, these implants are indispensable when the radial head fracture is associated with elbow instability. The indication for prosthesis may be questionable if the non-fixed fracture is free of associated ligament injury, as suggested by the good long-term reported after simple resection. Rigorous operative technique is crucial, with careful restitution of the radial height. The quality of the result is related to the degree of capsule and ligament injury even after optimal implant positioning. Preventive treatment against periarticular ossification should be systematic.

Adult↗
PubMed1998

Long-term mechanical reliability of multicomponent inflatable penile prosthesis: comparison of device survival.

OBJECTIVES: To determine the mechanical reliability of multicomponent inflatable penile prosthesis, comparing five different types of devices, as well as the two-piece versus three-piece as a group. METHODS: We followed 83 patients with two-piece and 283 patients with three-piece inflatable penile prostheses for a mean time of 66 months. At a cutoff of 63 months, mechanical complication rates were reviewed and statistically analyzed. RESULTS: Thirty-one device-related complications occurred, and all were secondary to fluid leakage. The Mentor Alpha-1 prosthesis was significantly better than the Mentor Mark-II in terms of mechanical reliability (P = 0.01). A trend was noted toward the AMS 700 Ultrex inflatable penile prosthesis having fewer mechanical complications than the Mentor Mark-II (P = 0.06). In addition, a trend toward all three-piece prostheses being more mechanically reliable than the two-piece was noted (P = 0.08). The Mentor Alpha-1 device had a higher cumulative proportional survival (0.957) than all other devices (0.842 for AMS 700 Ultrex, 0.839 for AMS 700 CX, 0.783 for Mentor GFS, and 0.750 for Mentor Mark-II). CONCLUSIONS: As a group, a trend was noted toward the three-piece prosthesis having better mechanical reliability than the two-piece prosthesis. Comparisons between the individual types of prostheses showed thatthe Mentor Alpha-1 device was significantly more mechanically reliable than the Mentor Mark-II device, and a trend was noted toward the AMS 700 Ultrex device having fewer mechanical complications than the Mentor Mark-II. The Mentor Alpha-1 prosthesis had the highest cumulative proportional survival.

Adult↗
PubMed1997

Reduction of polyethylene in a congruent meniscal knee prosthesis. Experimental and clinical studies.

Polyethylene wear was assessed in the Rotaglide congruent meniscal bearing total knee prosthesis and a partial congruent total knee prosthesis with fixed bearing polyethylene tibial platform and a posterior stabilizer mechanism. A special wear test rig was used to test the 2 prostheses under compression load of 2960 N/mm2 (about 4 times the average body weight) and continuous 0 degree-70 degrees flexion-extension motion at the rate of 1 cycle per second. The most remarkable finding was the lack of measurable wear on the Rotaglide meniscal bearing up to 3.5 million cycles, while the other prosthesis began to show wear from the first million cycles and progressed to 0.38 mm at about 3.5 million cycles. At 11 million cycles (about 20 years of life), the Rotaglide showed penetration wear of 0.35 mm compared to 2.1 mm in the other prosthesis. In 7 meniscal bearings, retrieved either at postmortem (2) or at reoperation (5), no measurable penetration wear was observed after 3 years of implantation. Only 1 prosthesis obtained 5 years after implantation showed 0.23 mm penetration wear or about 0.05 mm per year. These findings strongly suggest that the use of congruent meniscal bearing prosthesis can reduce the polyethylene wear in total knee replacement.

Arthroplasty, Replacement, Knee↗