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Dive into the research topics where Steven L. Wallrichs is active.

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Featured researches published by Steven L. Wallrichs.


Journal of Bone and Joint Surgery, American Volume | 1993

Proximal tibial osteotomy. A critical long-term study of eighty-seven cases.

Mark B. Coventry; Duane M. Ilstrup; Steven L. Wallrichs

Eighty-seven valgus osteotomies of the tibia were performed in seventy-three patients for osteoarthrosis of the medial compartment of the knee; the median follow-up was ten years (range, three to fourteen years). The data were subjected to univariate and multivariate statistical analysis and to survivorship analysis. For these calculations, the end-point of failure was defined as an arthroplasty of the knee, and additional calculations were performed with the end-point defined as the performance of an arthroplasty or moderate or severe pain in patients who had declined an arthroplasty. None of the many risk factors that were evaluated could be found to be associated with the duration of survival, except for relative weight and angular correction. The median loss of correction after the osteotomy was 1 degree. If, at one year after the operation, the valgus angulation was 8 degrees or more, or if the patients weight was 1.32 times the ideal weight or less, the probability of survival five years thereafter was at least 90 per cent and the probability ten years thereafter was at least 65 per cent. However, when valgus angulation at one year was less than 8 degrees in a patient whose weight was more than 1.32 times the ideal weight, the rate of survival decreased to 38 per cent five years thereafter and to 19 per cent ten years thereafter. There is a considerable risk of failure of a proximal tibial osteotomy if the alignment is not overcorrected to at least 8 degrees of valgus angulation and if the patient is substantially overweight.


Journal of Bone and Joint Surgery, American Volume | 1995

Total knee arthroplasty with the kinematic condylar prosthesis. A ten-year follow-up study.

A L Malkani; James A. Rand; Richard S. Bryan; Steven L. Wallrichs

Of 168 consecutive knees (118 patients) that had been treated with an arthroplasty with use of a kinematic total condylar prosthesis that allowed retention of the posterior cruciate ligament, 119 knees (eighty-four patients) were available for review at a mean of 10.0 +/- 0.7 years after the operation. The Hospital for Special Surgery knee score improved significantly, from a mean of 55 +/- 12 points preoperatively to a mean of 81 +/- 9 points at ten years (p < 0.0001). Radiolucent lines about the patellar component, present in thirty-five of eighty-three knees at the latest follow-up examination, were related to malpositioning of the tibial and femoral components. Six revisions were performed, and four of them were for a loose patellar component. The rate of deep infection was 1 per cent (one knee). Complications occurred in twenty-six knees (22 per cent). With revision as the end point, the rate of survival of the prostheses was estimated to be 96 per cent at ten years. The knee scores, the rate of survival of the implants, and the range of motion of the knees in the current study were similar to those reported previously for patients who had insertion of a total condylar prosthesis with sacrifice of the posterior cruciate ligament and for those who had substitution of the posterior cruciate ligament with a posterior stabilized prosthesis. A prosthesis that has a metal-backed tibial component and that allows preservation of the posterior cruciate ligament provides durable results, but loosening of the patellar component remains a major problem.


Foot & Ankle International | 1994

Cigarette Smoking and Nonunion after Ankle Arthrodesis

Tyson K. Cobb; Timothy A. Gabrielsen; Donald C. Campbell; Steven L. Wallrichs; Duane M. Ilstrup

The relative risk of nonunion in smokers versus nonsmokers after ankle arthrodesis was determined in a case control study. Twenty-two patients were matched to 22 controls by age, sex, surgeon, surgical technique, and preoperative diagnosis. Information on duration, amount, and past history of smoking was obtained for these 44 patients. Ten of the patients were actively smoking at the time of surgery compared with four of the controls. Six of the patients had no history of smoking and six had stopped smoking before surgery. Eleven of the controls had no history of cigarette smoking and 7 had stopped smoking before surgery. The relative risk of nonunion was increased 3.75 times for active smokers. When patients did not have any known risk factors for nonunion, the risk of nonunion for smokers was 16 times the risk of nonunion for nonsmokers


The Annals of Thoracic Surgery | 1994

Pulmonary resection of metastatic renal cell carcinoma

Robert J. Cerfolio; Mark S. Allen; Claude Deschamps; Richard C. Daly; Steven L. Wallrichs; Victor F. Trastek; Peter C. Pairolero

Between 1965 and 1989, 96 consecutive patients (64 men and 32 women) underwent complete pulmonary resection for metastatic renal cell carcinoma. Median age was 63 years (range, 33 to 82 years). Median time between nephrectomy and pulmonary resection was 3.4 years (range, 0 to 18.4 years). Forty-eight patients had solitary metastasis, 16 had two, 18 had three, and 14 had more than three. Wedge excision was performed in 62 patients, segmentectomy in 3, lobectomy in 25, bilobectomy in 3, and pneumonectomy in 3. Fourteen patients had repeat thoracotomy for recurrent metastasis; 34 other patients also had complete resection of limited extrapulmonary disease. There were no operative deaths. Median follow-up was 3 years (range, 70 days to 19.0 years). Overall 5-year survival was 35.9%. Patients with solitary metastasis had a 5-year survival of 45.6% compared with 27.0% for patients with multiple metastases (p < 0.05). Patients with a tumor-free interval greater than the median of 3.4 years had a better survival (p = 0.05) than those with a tumor-free interval less than or equal to 3.4 years. Five-year survival for patients who underwent repeat thoracotomy or had complete resection of extrapulmonary disease did not differ from overall survival. We conclude that resection of renal lung metastasis is safe and effective, that patients with solitary metastasis have a better survival than those with multiple metastases, that resectable extrapulmonary disease does not necessarily contra-indicate pulmonary resection, and that repeat thoracotomy is warranted in selected patients with recurrent lung metastases.


Journal of Bone and Joint Surgery, American Volume | 1994

Survivorship analysis of the Mayo total ankle arthroplasty

Harold B. Kitaoka; Gary L. Patzer; Duane M. Ilstrup; Steven L. Wallrichs

From 1974 until the end of 1988, 204 primary Mayo total ankle arthroplasties were performed at the Mayo Clinic. By means of actuarial analysis, we determined the cumulative rates of survival with failure (defined as removal of the implant) as the end point. The average duration of follow-up was nine years (range, two to seventeen years). By applying the Cox proportional-hazards general linear model, we identified two independent variables that were associated with a significantly higher risk of failure: a previous operative procedure on the ipsilateral foot or ankle and an age of fifty-seven years or less. The overall cumulative rate of survival at five, ten, and fifteen years was 79, 65, and 61 per cent, respectively. The probability of an implant being in situ at ten years was 42 per cent for patients who were fifty-seven years old or less and who had had previous operative treatment of the ipsilateral ankle or foot and 73 per cent for those who were more than fifty-seven years old and who had had no such previous operative treatment. We do not recommend the use of the Mayo total ankle arthroplasty, particularly in younger patients who have had a previous operative procedure on the ipsilateral ankle or foot.


Mayo Clinic Proceedings | 1991

Total Knee Arthroplasty: A Population-Based Study

Jeffrey P. Quam; Clement J. Michet; Marcus G. Wilson; James A. Rand; Duane M. Ilstrup; L. Joseph Melton; Steven L. Wallrichs

Total knee arthroplasty (TKA) is being used increasingly for the management of chronic arthritis of the knee. In this report, we review the frequency of application of TKA in the population of Olmsted County, Minnesota, from 1971 through 1986. The utilization rate of TKA increased from 20.5 per 100,000 person-years for 1971 through 1974 to 60.8 per 100,000 for 1983 through 1986. Although rates were higher in women, they increased with advancing age in both sexes. Rates between the urban and rural populations of Olmsted County did not differ. The two most common underlying diseases that necessitated TKA were osteoarthritis and rheumatoid arthritis; they were the cause of more than 90% of all operations. By extrapolating the rates of TKA in Olmsted County to the total 1986 US population, we estimate a need for at least 143,000 TKAs annually at a direct cost of more than


Mayo Clinic Proceedings | 1993

Trends in the Utilization of Primary Total Hip Arthroplasty, 1969 Through 1990: A Population-Based Study in Olmsted County, Minnesota

Rajan Madhok; David G. Lewallen; Steven L. Wallrichs; Duane M. Ilstrup; Robert L. Kurland; L. Joseph Melton

2.3 billion each year.


Clinical Orthopaedics and Related Research | 1996

Long term outcome and survivorship analysis of primary total knee arthroplasty in patients with diabetes mellitus.

Panayiotis J. Papagelopoulos; Osaretin B. Idusuyi; Steven L. Wallrichs; Bernard F. Morrey

Using the unique data resources of the Rochester Epidemiology Project, we identified the residents of Olmsted County, Minnesota, who underwent total hip arthroplasty (THA) between 1969, when this technique was introduced, and 1990. During this period, 735 residents underwent 859 primary THAs. An initial dramatic upsurge in utilization of THA soon after its introduction was followed by a lower rate of increase, to an age- and sex-adjusted rate of 59.9 per 100,000 person-years in 1987 through 1990. In Olmsted County, the procedure was used more often in women than in men, but men underwent THA at a younger age than did women. THAs were performed for various conditions of the hip, but the increased utilization during the last decade of the study was mainly attributable to its application in primary degenerative hip disease among patients (male more often than female) from a wider age range; utilization of THA for hip fractures decreased during the study period. Most THAs were of the cemented variety (86.1%); however, the rate of use of noncemented THAs, first performed in 1984, is increasing. The overall upward trend in Olmsted County was consistent with European data but less than the rate of increase observed for the United States as a whole between 1983 and 1987. Olmsted County utilization rates, if projected nationally, suggest a need for more than 139,000 primary THAs each year at an annual direct cost of more than


Journal of Arthroplasty | 1997

Bone-Graft Augmentation for Acetabular Deficiencies in Total Hip Arthroplasty Results of Long-term Follow-up Evaluation

Brian P. Lee; Miguel E. Cabanela; Steven L. Wallrichs; Duane M. Ilstrup

2.7 billion. An urgent need exists for detailed examination of national utilization patterns and clarification of the role of cementless implants and of THA for hip fractures.


Clinical Orthopaedics and Related Research | 1995

Acetabular reconstruction using bipolar endoprosthesis and bone grafting in patients with severe bone deficiency

Panayiotis J. Papagelopoulos; David G. Lewallen; Miguel E. Cabanela; Edward G. Mcfarland; Steven L. Wallrichs

Sixty-eight consecutive primary total knee arthroplasties in 51 patients with diabetes mellitus were assessed for long term outcome and risk factors. The mean followup was 8 years. There was a higher complication rate compared with that of a matched control group. Wound complications occurred in 4 knees, deep infection in 1, periprosthetic fractures in 3, and definite aseptic loosening in 5. Urinary tract infections occurred in 4 patients. Radiolucencies of more than 1 mm were observed in 38% of arthroplasties. At last followup, the Hospital for Special Surgery knee score was 77 ± 12 points, which is worse than the 86 ± 10 points of the control subjects. Only 74% of the patients had a satisfactory clinical result. Survivorship analysis showed a 91% probability of implant survival at 10 years, which was not significantly different from that of the control subjects. Previous surgery and increased weight were the only risk factors associated with implant failure.

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