Showing papers on "Prosthesis published in 1974"

Metal sensitivity as a cause of bone necrosis and loosening of the prosthesis in total joint replacement

Abstract: 1. Evidence is presented which suggests that after total joint replacement bone necrosis and consequent loosening of the prosthesis may be due to the development of sensitivity to the metals used. 2. Nine patients, from a total of fourteen with loose prostheses, were found to be metal sensitive by skin-patch testing. In twenty-four patients with intact prostheses no sensitivity was demonstrated. 3. In material from the joints of sensitive patients the metal content was raised. 4. Examination of this material showed necrosis of bone and soft tissue following obliterative changes in the vascular supply. 5. Similar reactions were found following the injection of cobalt into a sensitive patient. 6. The release of metal around a prosthesis is greatest where metal rubs against itself. 7. We conclude that prostheses in which metal articulates with polyethylene should be preferred; that any patient in whom loosening or fragmentation occurs should be patch tested; and that if sensitivity is found the implant should be removed.

Thrombosis on Bjork-Shiley aortic valve prosthesis: Clinical, arteriographic, echocardiographic and therapeutic observations in seven cases

Abstract: Seven patients with massive thrombosis on a Bjork-Shiley aortic valve prosthesis are described. This complication was documented in 5 percent of our patients with a Bjork-Shiley valve and occurred 3 to 19 months (mean 13 months) after insertion of the prosthesis. Only one patient had adequate anticoagulant therapy at the time of diagnosis. All patients had acute or subacute clinical deterioration. Anginal chest pain was the presenting symptom in four patients, and acute left ventricular failure in three. In all patients, the closing click of the Bjork-Shiley prosthesis was not heard, and new aortic systolic or diastolic murmurs were audible. Cardiac catheterization and aortic root cinearteriography were performed in five patients. Severe prosthetic regurgitation was found In four patients and mild regurgitation in one. Abnormal disc motion—fixation of the disc in the open position, abnormal limited opening of the disc or imperfect closure—was demonstrated in all arteriographic studies. Echocardiograms revealed an immobile disc in two patients. Five patients were surgically treated by thrombectomy and debridement of the prosthetic valve; the original prostheses were left in situ. Four of these patients are alive and one died. Two patients who did not undergo surgical treatment died. Thrombosis on the Bjork-Shiley aortic valve has a high fatality rate. Suspicion of this complication should be followed by emergency catheterization and surgery. In critically ill patients, surgery may be required even without angiography. The occurrence of this serious complication, mostly in patients with a normal coagulatory state, indicates the need for permanent anticoagulation in patients with a Bjork-Shiley aortic valve prosthesis.

Prosthetic Aortic Stenosis A Method to Prevent Its Occurrence by Measurement of Aortic Size from Preoperative Aortogram

Abstract: A cause of early death after aortic valve replacement with a caged-ball prosthesis is obstruction to left ventricular outflow because the prosthesis is too large for the aortic root. Of 68 patients dying within two months of aortic valve replacement, death in ten, each of whom had had intractable low cardiac output after operation, was attributed at necropsy to prosthetic aortic stenosis, despite the use of small sized (8A Starr-Edwards) prostheses in seven of them. The diameters of the aorta at the sinotubular junction, determined from the preoperative cineangiograms, in the seven patients with prosthetic stenosis were 30 in all but one, and the poppet clearances ranged from 12 to 19 mm (avg. 15)...

Rehabilitation of the Geriatric Amputee

Abstract: During a five-year period, 90 patients who had undergone lower-extremity amputations when aged 60 or older were treated at the Amputee Clinic of the Jewish Hospital of St. Louis. Seventeen of the 90 were not fitted with prostheses because of various medical contraindications. Thirteen of the remaining 73 patients who were fitted with prostheses had died by the time of follow-up, and 23 others could not be located. Of the 37 known survivors, 23 wore their prosthesis for more than six hours daily and used it as their main mode of locomotion; 14 used it only occasionally or not at all. Sex and age at the time of amputation were of little value in predicting the success of prosthetic rehabilitation. Patients with below-knee amputations fared much better than those with above-knee amputations. Contraindications to fitting an aged amputee with a prosthesis are mental deterioration, congestive heart failure, severe angina pectoris, and advanced chronic obstructive pulmonary disease. Neurologic disorders such as parkinsonism or stroke with a significant neurologic residual are additional contraindications. Patients who have ulcerations or infections of the remaining extremity or who have severe contractures of the stump usually cannot be fitted with a prosthesis. The ability to use axillary crutches is not a realistic prerequisite for supplying an aged amputee with a prosthesis. A patient who has walked before the amputation and who afterward can walk with a walker, usually will be able to use an artificial limb. Amputees who cannot be expected to use a prosthesis can still be rehabilitated to an independent wheelchair existence.

ACRYLIC LUNATE PROSTHESES: A Long-term Follow-up

Abstract: 1. Fourteen patients whose Kienbock9s disease was treated by prosthetic replacement, and who have had an acrylic lunate prosthesis in place for periods of eight to twenty years, have been reviewed. 2. In most patients pain, weakness and limitation of movement are less than they were before operation. Four wrists are completely painless and the other ten have only occasional slight pain. The average range of antero-posterior movement is 100 degrees. 3. Radiological signs of osteoarthritis are either absent or slight in ten wrists: this is considered to be due to the success of the prosthesis in maintaining the carpal architecture, even after prolonged heavy use.

Total surface replacement of the hip joint.

Abstract: The surface replacement hip prosthesis reported represents an attempt to improve upon some aspects of the present design of total hip. The prosthesis comprises a cap fitted over the femoral head and a liner fixed into the socket, both being cemented with methyl methacrylate. The chief advantage of this design is preservation of bone stock. The prostheses were inserted bilaterally into six dogs, and whilst ten joints failed, one case was strikingly successful at two years follow-up. It was concluded that the design showed sufficient advantages over current total hips and that there was sufficient possibility of success in some application, to merit further study.

Experience with the Björk-Shiley prosthetic valve.

Abstract: Gratifying results were obtained with the Bjork-Shiley prosthesis in this series of 63 patients. The surgical mortality of the entire series was 7,9%. Late morbidity was negligible.