Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PROSTHESIS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,009 records · Page 56Linked to original sources

Hollow and fenestrated penile prosthesis: a new implant for treatment of impotence.

Penile implants are used for erectile dysfunction (ED). Their main disadvantage is that the cavernous tissue is destroyed and replaced by fibrous so that implant replacement is difficult and the penis loses its erectile function permanently. This paper describes a novel prosthesis which is hollow and fenestrated to preserve, as much as possible, the cavernous tissue. The fenestrated implant was used in 18 men with ED, while the solid Small-Carrion implants were used in 14 impotent men who matched the 18 men in age and cause of impotence and acted as controls. Routine erectile function tests suggested that the ED was neurogenic. The fenestrated prosthesis was a hollow semisolid silicone rod with multiple openings (2-3 mm in diameter) along its whole length. The mean follow up of the patients was 43 +/- 12 SD months. No complications were encountered. Vaginal penetration was successful in the fenestrated and Small-Carrion implant groups. A total of 14/18 patients of the fenestrated prosthesis group experienced spontaneous erections upon sexual arousal, while none of the Small-Carrion prosthesis group did. During the sexual act the penis became tumescent in the patients of the former group but not in those of the latter. It is suggested that the residual cavernous tissue after insertion of the hollow fenestrated implant regenerates through the fenestrae into the implant lumen. This might explain the spontaneous erections upon sexual arousal and the tumescence during the sexual act, but this hypothesis remains to be proved histologically.

Adult↗

A roentgenological study of the stump-socket contact and skeletal displacement in the PTB-Suciton Prosthesis.

The PTB-suction prosthesis has been studied by a roentgenological technique. There is complete contact between the skin of the stump and the plastic inner surface of the socket. The movement of the stump in the socket is minimal. The displacement of the skeletal stump is reduced to half in the PTB-suction prosthesis, compared with the strap-suspended PTB prosthesis. As a result, the stability between stump and socket is increased, provided that the stump is sufficiently long. Skin sores are avoided. The prosthesis, when adequately fitted, guarantees a good circulation within the stump and a cosmetically favourable fit with a feeling of walking with "a normal leg".

Adult↗

The geriatric prosthesis as metaphor: a clinical note.

This clinical note describes a 96-year-old patient who wears a lengthening prosthesis in connection with the shortening of his leg which occurred after osteomyelitis of his left knee at the age of six years. The prosthesis was made and issued to him when he was twelve years old, and had never been replaced. The considerations that need to be made when replacing the prosthesis of an elderly patient are discussed. In the case described, the prosthesis is replaced by a model that has no fundamental changes from the original. The better fit improves walking considerably and the patient is able to move about safely again using a walking frame.

Age Factors↗

A new modular six-bar linkage trans-femoral prosthesis for walking and squatting.

Four-bar linkage mechanisms produced by many designers of knee joints for trans-femoral prostheses can provide knee rotation to permit walking only. In Afro-Asian countries people are accustomed to a squatting posture in their daily activities. A six-bar linkage knee-ankle mechanism trans-femoral prosthesis is described which was developed and fitted to an amputee. The motion patterns of the ankle, knee and thigh during walking and squatting (obtained using a flickering light emitting diode system) for the above prosthesis is compared with motion patterns obtained for normal subjects. The closeness between both the patterns establishes the suitability of the new modular trans-femoral prosthesis for producing near normal patterns of motion during walking and squatting. The additional facility of cross-legged sitting provided in the prosthesis makes it functionally suitable for Afro-Asian amputees.

Amputees↗

An "appropriate technology" trans-femoral prosthesis, using materials available in Nepal.

The use of western components and materials for prostheses is prohibitively expensive in most developing countries. In addition, local customs and conditions vary considerably from those for which the prostheses were designed. For these reasons, a trans-femoral prosthesis has been developed in Pokhara, Nepal, using entirely locally available materials, and with a view to fulfilling local requirements as far as possible. This paper describes the materials and fabrication technique for the component parts of the prosthesis, the local conditions for which it was developed, and a three year follow-up of the first prosthesis issued. Only one serious design fault was discovered during this period, and a modification to the fabrication procedure introduced. The authors believe that if this trend continues, this style of prosthesis may be useful in the future for Nepali amputees and perhaps also in other countries, particularly where mass production of components is not practical.

Artificial Limbs↗

Nonthrombogenic ac polarized copper prosthesis.

In previous studies from our laboratories, it was shown that metals and alloys which register negative potentials in blood vs the normal hydrogen electrode tend to be antithrombogenic while those with positive potentials are invariably thrombogenic. The present paper deals with a novel approach of maintaining an implanted metallic prosthesis at a negative potential. A copper vascular prosthesis in a dog was maintained at cathodic potentials by a small amplitude (+/- 10 mV) high-frequency ac (100 kHz) on the prosthesis. The prostheses were removed after 2 hours, 6 hours, 1 day, and 42 days, with subsequent visual and scanning electron microscopic examination of the prostheses completed. All tubes were free of thrombus deposits. Minimal junctional thrombi were found, probably due to differences in physicochemical characteristics of the vascular prostheses and recipient vessels. The results are compared with those in the control group (copper tubes with no current) and dc polarized copper tubes. While the control tubes occluded in 2 to 6 hours, the dc and ac polarized tubes remained patent. Of the ac and dc polarized tubes, the former tubes lasted up to 6 weeks with less thrombus deposit. The mechanism of operation of the ac polarized copper prosthesis is not fully understood.

Animals↗

The Björk-Shiley tilting disc valve prosthesis. Echocardiographic findings.

The echograms obtained following Björk-Shiley valve replacement are described-first, on an experimental model and later, in vivo. The echogram obtained consisted essentially of four main horizontal waves. Their origin is clarified. In artificially created peri-prosthesis leaks, a normal trace was obtained, while in trans-prosthesis leaks, a reduction in amplitude of motion occurred and the valve remained open in diastole (aortic valve). In vivo, a normal trace was obtained in peri-prosthesis leaks. Trans-prosthesis leaks with the Björk-Shiley valve have not hitherto been described, but the potential of echoscanning in detecting disc dysfunction is put forward.

Adult↗

Dysfunction of the Björk-Shiley prosthesis. Report of 32 cases.

We present 32 cases of dysfunction of the Björk-Shiley valvular prosthesis, representing 3.01% of the 1,063 BS prostheses implanted at this clinic. The complications observed were thrombosis of the prosthesis, suture dehiscence with or without endocarditis and disc-suture interference. In selected, favourable cases, we prefer thrombectomy with generous washing of the prosthesis and rotation of the disc, without removal of the disc from the prosthesis. Furthermore, when the dehiscence does not exceed 1/3 of the circumference of the ring, we have achieved very good results with single sutures supported on Teflon patches. Subsequent failures of this procedure were not of a technique nature, but rather due to the poor condition of the patients. In situations of clinical emergency, the diagnosis of valvular dysfunction may suffice as indication of surgery, further diagnostic measures being postponed in view of the data of the physical exploration.

Adolescent↗

Enucleated eye model for intraocular retinal prosthesis implantation.

An enucleated porcine eye model was developed to assess intraocular retinal prosthesis implantation surgery. The surgical technique consists of corneal and crystalline lens removal, keratoprosthesis replacement, and vitrectomy. To test the eye model, the scleral incision was increased to 5 mm and a 10-mm wide retinal prosthesis folded and inserted. One retinal tack was used to fix the prosthesis to the retina. A retinal prosthesis array was inserted without significant damage to the array and conformed to the curvature of the eye. Fundus photography and optical coherence tomography were performed at the end of surgery.

Animals↗

Hypothermia reduces neurologic deficits associated with placement of a vascular prosthesis in the abdominal aorta of rabbits.

Treatment for atherosclerotic vascular disease in human beings ranges from medical management to interventional therapy, such as angioplasty, atherectomy, and bypass grafting. Recently, bypass grafting with a vascular prosthesis has received increased attention and clinical use. In the course of studies to optimize use of a small-caliber vascular prosthesis, five of six rabbits undergoing implantation of a polytetrafluoroethylene vascular prosthesis in the infrarenal abdominal aorta developed hind limb neurologic deficits, which resulted from focal ischemic damage to the spinal cord attributable to temporary vascular occlusion of the abdominal aorta during placement of the vascular prosthesis. In subsequent studies, induction of systemic hypothermia decreased the rate of development of neurologic deficits from 83 to 9% without any apparent perioperative complications associated with decreased body temperature. We determined that mild hypothermia (rectal temperature of 32 to 35 degrees C), combined with aortic occlusion time of < 40 min, is sufficient to afford protection from ischemic injury to the spinal cord in the rabbit.

Animals↗

[Treatment of inoperable malignant gastric stenosis with self-expanding prosthesis].

We report two patients with inoperable malignant stenosis of gastric antrum who were treated with endoscopic placement of a 22 mm Wallstent metallic prosthesis. In one patient, the endoscope was introduced simultaneously with the prosthesis. Different types of pincers were introduced through the endoscope's canal, which aided the movement and placement of the prosthesis. In the other patient, to broaden the stenosis a pediatric endoscope was introduced with a guide inside the canal, which was held straight externally and which facilitated the positioning of the prosthesis. There were no complications and the patients were discharged after 48 hours able to follow a normal oral diet. Both patients are still living, six and four months respectively after the procedure.

Adenocarcinoma↗

[Osteolysis after total knee prosthesis].

PURPOSE OF THE STUDY: The aim of our work was to study X-rays showing osteolysis after 5 years and more in 122 prosthesis and to try and assess such complication, often described in the United States but seldom in Europ. MATERIAL: We are dealing here with 122 retaining posterior cruciate ligament, mostly cementless prothesis implanted between 1985 and 1992 84 chromium-cobalt prosthesis (PCA and Themis) implanted in 34 males and 88 females with an average age of 67 (45-81), 87,7 p. 100 had femoral cementless components and 70 p. 100 tibial cementless components. METHODS: All patients were examined and had X-rays at an average of 6,9 years. Specially considered were X-rays showing a possible osteolysis. We looked for possible complication (external laxity, anterior femoral dislocation and polyethylene wear), assessment of the mechanical axis and for clinical results (Hungerford score) RESULTS: Revisions: 19 arthroplasties were revised for PE wear tibial loosening metallosis or patella problems The postoperative score according to Hungerford was 84,5 p. 100 for PCA prosthese and 87 p.100 for the Themis. On the X-rays were only few osteolysis to be found: 9 cases (7,3 p. 100). For the PCA series: 3 femoral osteolysis, 1 tibial at 12 years, and one patellar osteolysis. For the Themis series: no femoral osteolysis, 3 tibial and one patellar osteolysis. Osteolysis are apparent on X-rays in profile for the femur and the patella, and in both profile and frontal X-rays for the tibia. Clinicaly 4 osteolysis really asymptomatic were not re-operated. 5 were revised: one 11 years later for femoral and tibial loosening, two for a patellar loosening, the other two patients had to be reoperated on for metallism (titanium's femoral component) and for those two instances osteolysis were discovered during the complication. DISCUSSION: Osteolysis after TKA appears unusual in our experience without bearing on frequency finded by american authors with a lesser follow-up (Engh 11,1 p. 100 after 4,5y, Peters 16 p. 100 after 2,9 y, Robinson 9,18 p. 100 after 4,6 y). American litteratur analysis shows that the important number of osteolysis is due to: - either to dual-metal using (Co-Cr component with Titanium screws for exemple), - or bad quality of polyethylene (compressed), - or a bad design of former prosthesis. CONCLUSION: Interface illness, linked to the production of wear debris, osteolysis after total knee arthroplasty is rarer than after a hip one, probably because size of debris is different, larger in knee than in hip. It is likely that the improvement of PE quality, design of prosthesis, as well as a better knowledge of osteolysis mechanism will allow to delay this complication wich is in a long term ineluctable.

Aged↗

[Results of the use of a new vascular prosthesis "Vitaflon" in patients with critical ischemia of the lower limbs].

A new Russian vascular artificial prosthesis from porous PTFE ("Vitaflon") was used in 39 cases of different obliterative arteriopathy in the critical ischemia phase, moreover in 12 cases with foot gangrene. The diagnoses for all the patients (35 men, 4 women, average age 57.8 years) were made in accordance with the clinical data, arteriography and ultra-sound imaging. In 15 cases the cause of ischemia was thrombo-obliteration of the aorto-femoral and in 24 cases of the femoro-popliteal segments. The following bypass operations were made: aorto-femoral graft implantation in 3 cases, ilio-femoral in 7 and ilio-popliteal in 2 cases, extra-anatomical femoro-femoral bypass graft in 4 cases and axillo-bifemoral in 1 case, femoro-popliteal above the knee bypass in 17 cases, in 2 cases explant-profundi femoral, in 1 case popliteal-peroneal prosthesis and in 2 cases profundoplasty. The postoperative period showed 1 graft thrombosis with a successful thrombectomy. In one case an infection of the femoro-femoral prosthesis was registered which was removed. In the long-term period up to 4 years thrombosis was registered in 6 cases with femoro-popliteal and in 2 cases with ilio-popliteal and ilio-femoral bypass grafts. High limb amputation had to be done in 5 cases. During this period 8 patients died from the causes other than operation. 28 cases with working grafts were followed-up, they underwent duplex-doppler investigation and in 4 cases arteriography. The first results showed excellent qualities of the new prosthesis which can be compared with those of the best similar models.

Angiography↗

[Dislocation into the cardial lumen of a PTFE prosthesis used in the treatment of voluminous hiatal sliding hernia, A case report].

The authors report a case in which a PTFE prosthesis, used to treat a voluminous hiatal sliding hernia, dislocated inside the cardial lumen. Within two months the prosthesis had become decubitant and penetrated the cardial lumen, causing dysphagia, inappetence and weight loss. The use of radiological and tomographic imaging failed to provide a clear diagnosis; endoscopy alone was conclusive. Surgery was required to remove the prosthesis by resecting the distal esophagus and reconstructing the continuity of the digestive tract using terminolateral esophagogastric anastomosis (front wall of the stomach) in CEEA 21. The absence of a clear etiopathogenetic sequence of the migration of the prosthesis prompted the authors to stop using this type of surgery.

Aged↗

Significance of non-level walking on transtibial prosthesis fitting with particular reference to the effects of anterior-posterior alignment.

Despite the fact that non-level walking is known to be important for prosthesis fitting, its clinical significance has not been investigated. In this study, the acceptable prosthesis alignment ranges of six subjects with transtibial amputation on level and non-level walking were determined and compared. With the aid of a recently developed alignment jig, prosthesis fitting was performed for each subject with varied anterior-posterior (AP) alignments. Conventional assessments and the subjects' comment were used to determine whether the alignment was acceptable or not. The results showed that the acceptable alignment range for non-level walking consistently fell within and was significantly smaller than that for level walking with p<0.05. It was evident that non-level walking is important for better approximation of optimum alignment and should be included in routine prosthesis fitting.

Adult↗

[Allograft-prosthesis combination in limb salvage surgery].

OBJECTIVE: To study allograft-prosthesis combination in limb salvage and the rational of composite prosthesis. METHODS: Of 16 patients with bone tumors age from 19 to 60 years, 6 women 12 men, osteosarcoma was found in 4 patients, chondrosarcoma in 2, malignant giant cell tumor in 3, fibrosarcoma in 3, and other malignant bone tumor in 4. Allograft-prosthesis combination in included allograft proximal femurs with total hip arthroplasty (3 patients), allografts bipolar femoral head replacement (8), allografts with total knee arthroplasty prosthetic replacements (7). All patients received adjuvant therapy for tumor control. RESULTS: The length of follow-up ranged from 18 months to 5 years during which time 1 patients died, 3 survived as tumor-carriers, and 12 were disease free. All patients obtained better functional result in their extremities and had good quality of life. CONCLUSIONS: Both prosthetic replacement and allograft advantages, the use of large bone allografts with metallic prosthesis for the treatment of bone tumors near or involving joints can be applied with good results in selected patients having limb salvage surgery.

Adult↗

[Experimental study on three-dimensional adjustable condyle prosthesis for reconstruction of temporomandibular joint].

OBJECTIVE: To study the possibility of reconstructing TMJ with a modified three-dimensional adjustable condylar prosthesis (TDACP). METHODS: The modified TDACP was placed immediately after resection of the mandibular ramus and condyle in 3 adult rhesus monkeys. The results were evaluated by radiography, histological and anatomical examinations, as well as chewing function at 3, 6, and 14 months after surgery. RESULTS: Through adjustment the condyle prosthesis could fit exactly, the functions were good, every part of the prosthesis was firm, the screws were osteointegrated, there was no adverse soft tissue reactions and no pathological changes in the TMJ of non-operated opposite condyle. Problems were: the distribution of fixation stress of screws was somewhat unreasonable, the downward sliding of the condyle was limited, there was erosion of the posterior slope of the glenoid fossa, and the articular disc could not keep its in situ place and function. CONCLUSION: The results suggests that the prosthesis needs further improvement.

Animals↗

[Results of an inverted shoulder prosthesis after resection for tumor of the proximal humerus].

PURPOSE OF THE STUDY: Treatment of primary bone tumors of the proximal humerus is a major challenge, both in terms of oncological cure and limitation of functional handicap. Extracorporal radiation and reimplantation have provided satisfactory results for the treatment of bone tumors and the inverted shoulder prosthesis has be found to be effective in treating rotator cuff deficiency. We therefore assessed patients treated with a combination of these two treatments in order to search for a better functional outcome. MATERIAL AND METHODS: Conservative resection of the tumor with reconstruction using an inverted shoulder prosthesis was performed in six patients with a tumor of the proximal humerus of type Ia or Ib in the Malawer classification or type S3-S4-S5 in the Musculoskeletal Tumor Society classification. Patients whose tumor involved the deltoid or the glenohumeral joint were not considered for this procedure. The series included four men and two women (4 left and 2 right shoulders) aged 51 years on the average at the time of surgery. RESULTS: Mean follow-up was 12 months. The mean age- and sex-adjusted Constant score was 74% (70-85%). The patients were generally satisfied and were able to continue their daily activities. There were two displacements, one of which was diagnosed immediately and reduced without anesthesia. An abduction pad was worn for six months after reduction. The post-operative period was uneventful. No local recurrence has been observed. DISCUSSION: Our results compared favorably with other therapeutic options for resection-reconstruction reported in the literature: functional outcome was better and more predictable, at least in the short term; oncological results were satisfactory although the follow-up is short, particularly for the three primary malignant tumors. It is known however that the long-term oncology result depends on the quality of the resection and the efficacy of the extracorporeal radiation. Shoulder motion outcome was the least satisfactory in patients who experienced peri-operative complications. We were unable to find any relation between less satisfactory functional outcome and the number of surgical procedures for local recurrence before extracorporeal radiation and arthroplasty (deltoid dystrophy). Normal deltoid function appeared to be crucial for optimal functional outcome with this prosthesis which allows sacrifice of the rotators. The rate of complications was low and recovery of active shoulder movement was more rapid. Despite the short-term nature of these results, and despite the risk of loosening, the inverted shoulder prosthesis appears to be an interesting therapeutic option for these patients.

Activities of Daily Living↗