[Total knee replacement with ceramic femoral components: a national prospective multicenter study of clinical and radiological outcomes].
ABSTRACT The purpose of this prospective multicenter study was to evaluate the clinical and radiological outcomes of an unconstrained bicondylar total knee prosthesis with a new ceramic femoral component made of BIOLOX® delta.
Fifty patients underwent cemented total knee arthroplasty in three hospitals/centers. Clinical and radiological evaluations were undertaken preoperatively and at 3 as well as 12 months postoperatively using the HSS, WOMAC, and SF-36 scores.
During 12 months follow-up three patients had to undergo revision surgery due to non-implant-related reasons (infection, periprosthetic fracture, and retropatellar replacement). The mean preoperative HSS score amounted to 56.2±11.0 points. At 3 and 12 months follow-up the mean HSS score was 75.5±11.5 and 83.6±10.9 points, respectively. Therefore, HSS and WOMAC scores improved significantly from preoperative values at both postoperative evaluations. The first significant improvement of SF-36 score was seen after 12 months. Radiolucent lines around the femoral ceramic components were found in one case.
Subsequent long-term studies must be carried out in order to clarify the potential benefits of ceramic femoral components and confirm the good early clinical result. Moreover, the specific material properties of ceramic implants must be considered during implantation.
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ABSTRACT: The Ilizarov method of lengthening was used to correct deformities of the lower extremity in six patients who had type-1 osteogenesis imperfecta, as categorized by Silence et al. The average age was thirty-one years (range, fourteen to fifty-one years). The deformities included shortening of four tibiae and three femora as well as an angular malalignment (average, 28 degrees; range, 20 to 40 degrees) of all four tibiae and one femur. One patient also had a non-union of the right femur. The average angular correction was 23 degrees (range, 20 to 30 degrees). The seven limb segments gained an average of 6.6 centimeters (range, two to eleven centimeters) in length. All limb-length discrepancies were corrected to within two centimeters of the length of the contralateral limb. At an average of three years and four months (range, one year and seven months to six years), the roentgenographic appearance of the fully matured bone was comparable with that of the original bone. There was no fractures or increases in the angulation of the segment of new bone. Two patients had pain when walking; it was related to a chronic pin-track infection in one and to osteoarthrosis of the ankle in the other. The functional status of four patients was improved and that of the other two patients was unchanged. All six patients were pleased with the outcome of the procedure. There was eighteen complications: stiffness of the knee in two patients; a peroneal nerve palsy in two; a superficial pin-track infection in three; and a deep pin-track infection, greater-than-normal loss of blood intraoperatively, loosening of two pins, worsening of the instability of the knee, and an infection in the knee in one patient each. In another patient, a Rush rod that had been placed before correction of the deformity migrated proximally and had to be removed after completion of the correction. There were five fractures.The Journal of Bone and Joint Surgery 03/1996; 78(2):220-5. · 3.23 Impact Factor
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ABSTRACT: One hundred and eighteen patients who had had 150 consecutive primary total knee replacements (sixteen bilateral procedures) between February 1988 and February 1990, with insertion of the press-fit condylar modular total knee system with cement, were enrolled in a prospective study. Ninety-six patients (125 knees) were followed for an adequate interval (mean, 4.8 years; range, 3.8 to 6.2 years). Thirteen patients (fifteen knees) died, and nine patients (ten knees) were lost to follow-up. The mean age of the patients at the time of the index arthroplasty was seventy years (range, twenty-nine to eighty-five years). The patients were evaluated clinically and radiographically, according to the scoring system of the Knee Society, and the results on a self-administered questionnaire were used to evaluate pain, function, satisfaction, and patellofemoral symptoms. A Kaplan-Meier survivorship analysis was performed with a revision operation as the end point. The mean functional and clinical scores, according to the system of the Knee Society, were 78 and 93 points, respectively, at the most recent follow-up examination. The result was excellent for 103 knees, good for thirteen, fair for three, and poor for six. Three revision operations were necessary: two because of infection and one because of instability. The over-all rate of patellofemoral symptoms was 8 per cent (ten knees). Three knees had tibiofemoral instability; subsequent modification of the design of the tibial cam decreased the prevalence of this problem. Non-progressive radiolucent lines were present at the cement-bone interface in 39 per cent (thirty-nine) of the ninety-nine knees that had complete radiographic follow-up. No prosthesis had loosened by the time of the most recent follow-up examination. The rate of survival of the implant was 97 per cent at six years, and the standard error of the mean was 1.6 per cent. In the present series, total knee arthroplasties with the press-fit condylar modular knee system resulted in excellent relief of pain, an excellent range of motion, and restoration of function. They were also associated with a low prevalence of patellofemoral problems.The Journal of Bone and Joint Surgery 04/1997; 79(3):342-8. · 3.23 Impact Factor
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ABSTRACT: The Bisurface knee prosthesis was designed in 1989 to improve knee flexion without affecting the durability of the prosthesis. The prosthesis has a unique ball-and-socket joint in the midposterior portion of the femoral and tibial components, which functions as a posterior stabilizing cam mechanism and causes femoral rollback. The femoral component was made of alumina ceramic. The purpose of this study was to review the clinical results of the first 223 arthroplasties performed with this prosthesis in order to assess whether this new implant had achieved its design objectives. From December 1989 to May 1994, all patients who were scheduled for primary total knee arthroplasty were enrolled in a prospective study of the Bisurface knee. The patients were evaluated clinically according to The Hospital for Special Surgery knee-rating system and with a self-administered questionnaire, and they were evaluated radiographically according to the system of the Knee Society. Kaplan-Meier survivorship analysis was performed with revision of the knee or recommendation for revision as the end point. One hundred and sixty-six patients treated with a total of 223 consecutive primary total knee arthroplasties were enrolled in the study, and 182 knees were followed for 3.9 to 9.0 years (mean, 5.8 years). Preoperatively, the mean Hospital for Special Surgery knee score was 44.5 points. At the time of latest follow-up, the mean knee score was 86.3 points. The mean preoperative and postoperative ranges of flexion were 119 and 124 degrees, respectively. The patients, even those with a good preoperative range of motion, rarely lost deep flexion of the knee after the procedure. A revision operation was performed in eight knees (because of infection in five, instability in two, and breakage of the peg of the patellar component in one). Two knees had recurrent medial-lateral subluxations of the femorotibial articulation, which were treated nonoperatively. No prosthesis had loosened aseptically and no alumina ceramic femoral component had broken by the time of latest follow-up. The rate of survival of the implant was 94 percent (95 percent confidence interval, 90 to 98 percent) at six years. According to the patient questionnaires, 20 percent of the knees sometimes felt loose in daily living activities, which prompted us to improve the intrinsic stability of the prosthesis by improving the congruity of the ball-and-socket joint. Total knee arthroplasty with the Bisurface prosthesis resulted in an excellent range of motion and a high level of satisfaction with the operation; the durability of the prosthesis is promising.The Journal of Bone and Joint Surgery 12/2000; 82-A(11):1626-33. · 3.23 Impact Factor