Steve S. Liu
University of Iowa
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Journal of Bone and Joint Surgery, American Volume | 2005
John J. Callaghan; Christopher W. Wells; Steve S. Liu; Devon D. Goetz; Richard C. Johnston
We previously evaluated 119 consecutive total knee arthroplasties that were performed in eighty-six patients with use of the cemented LCS (low contact stress) rotating-platform system with an all-polyethylene patellar component. The average age of the patients at the time of surgery was seventy years (range, thirty-seven to eighty-eight years). The purpose of this study was to report the updated results at a minimum follow-up of fifteen years. Thirty-seven patients (fifty-three knees) were living, and no patient was lost to follow-up. No knee was revised because of loosening, osteolysis, or wear. Three knees required a reoperation (two for periprosthetic fractures and one for infection). No component was revised as a part of the reoperations. Osteolysis was present in three knees. No knee had radiographic signs of component loosening, and there were no dislocated bearings. The average range of motion was from 1 degrees of extension to 105 degrees of flexion. The average clinical and functional Knee Society scores were 43 and 49, respectively, at the preoperative evaluation and 85 and 58 at the time of the final follow-up. We concluded that the cemented LCS rotating-platform knee performed well, with durable clinical and radiographic results at a minimum follow-up of fifteen years.
Journal of Bone and Joint Surgery, American Volume | 2004
John J. Callaghan; Jesse E. Templeton; Steve S. Liu; Douglas R. Pedersen; Devon D. Goetz; Patrick M. Sullivan; Richard C. Johnston
The purpose of the current study was to update the results of a prospective, single-surgeon series of primary Charnley total hip arthroplasties performed with cement. This investigation is one of the first studies in which hips treated with total hip arthroplasty with cement were followed for a minimum of thirty years. Twenty-seven patients (thirty-four [10.3%] of the hips in the initial study group) were alive at a minimum of thirty years postoperatively. These patients served as the focus of the present study. Revision because of aseptic loosening of the acetabular component was performed in 7.3% (twenty-three) of the hips from the original study group (excluding those revised because of infection or dislocation) and 26% (eight) of the hips in the living cohort. Revision because of aseptic loosening of the femoral component was performed in 3.2% (ten) of the hips from the original study group (excluding those revised because of infection or dislocation) and 10% (three) of the hips in the living patients. Since the twenty-five-year review, three hips were revised (one because of acetabular loosening, one because of femoral loosening, and one because of instability). This end-result study demonstrated the remarkable durability of cemented Charnley total hip replacements over a span of three decades, with 88% of the original prostheses intact at the time of the final follow-up or at the patients death.
Clinical Orthopaedics and Related Research | 2005
Michael R. O'rourke; Jj Gardner; John J. Callaghan; Steve S. Liu; Devon D. Goetz; David A. Vittetoe; Patrick M. Sullivan; Richard C. Johnston
We report the results of a minimum 21-year followup of a consecutive series of 103 patients who had 136 Marmor cemented unicompartmental knee replacements done between 1975 and 1982. Patients were evaluated clinically and radiographically. At minimum 21-year followup 14 patients (19 knees) were alive, 87 patients (115 knees) had died, and only two patients (two knees) were lost to followup. The average age at surgery was 70.9 years. The average followup Hospital for Special Surgery knee score was 58. The average Knee Society final followup clinical and functional scores averaged 72 and 53 points, respectively. Nineteen knees (14%) were revised during the 21-year followup period: nine for progression of disease, eight for loosening, and two for pain, at an average of 10.6 years (range, 1-22 years). Of the 19 knees in the 14 patients who were still alive at final followup, seven (37%) were revised: two for tibial loosening, four for disease progression, and one for pain. Unicompartmental knee replacements in this relatively older age group of patients performed well at minimum 21-year followup. Although we are encouraged by these results, only 22% were done in patients who were younger than 65 years at the time of surgery and the results in this group were significantly less durable. Level of Evidence: Therapeutic study, Level IV-1 (case series). See the Guidelines for Authors for a complete description of levels of evidence.
Journal of Bone and Joint Surgery, American Volume | 2011
John C. Clohisy; Michael A. Dobson; Jason Robison; Lucian C. Warth; Jie Zheng; Steve S. Liu; Tameem M. Yehyawi; John J. Callaghan
BACKGROUND Significant controversy exists regarding the causes of premature, natural hip-joint failure. Identification of these causes may guide future investigations targeting prevention of this disorder. The aims of this study were to: (1) determine and characterize structural abnormalities associated with premature, natural hip-joint failure, and (2) analyze disease progression in the contralateral hips of patients with femoroacetabular impingement deformities. METHODS We analyzed 604 patients (710 hips) from three different medical centers who underwent primary total hip arthroplasty at or before fifty years of age (average age, forty years). Three hundred fourteen patients (52%) were male, and 290 patients (48%) were female. RESULTS The diagnoses associated with premature hip failure varied, but osteoarthritis and osteonecrosis were most common. Radiographic abnormalities associated with developmental hip dysplasia and femoroacetabular impingement were associated with the majority of osteoarthritic hips. Hips with femoroacetabular impingement deformities demonstrated distinct structural anatomy relative to asymptomatic hips, with a high prevalence of bilateral deformities. In a subgroup of seventy patients with femoroacetabular impingement deformities, contralateral radiographic disease progression or the need for total hip arthroplasty was observed in 73% of hips. CONCLUSIONS Osteoarthritis and osteonecrosis are the major causes of premature hip-joint failure in young patients. Femoroacetabular impingement abnormalities are usually bilateral and are commonly associated with progression of the disease to the contralateral hip.
Journal of Bone and Joint Surgery, American Volume | 2009
John J. Callaghan; Peter Bracha; Steve S. Liu; Somyot Piyaworakhun; Devon D. Goetz; Richard C. Johnston
The purpose of this study was to update the results, at a minimum of thirty-five years, in a single-surgeon series of primary Charnley total hip arthroplasties performed with cement. Twelve patients (fifteen hips) were alive, 249 patients (314 hips) had died, and one patient (one hip) had been lost to follow-up. Seven of the hips in the living patients had required at least one revision; 290 (88%) of the original group of total hip prostheses either continued to function or were in patients who had died. Since the time of a thirty-year study of this cohort, one hip that had previously been revised because of acetabular loosening required an additional revision because of acetabular loosening and two additional hips had evidence of radiographic loosening (of one acetabular and one femoral component). The survival rate with revision for any reason as the end point was 78%. This end result study should provide a benchmark for subsequent procedures and designs with the caveat that patient life expectancy will likely continue to increase and modern-design implants are being used in younger patients.
Journal of Bone and Joint Surgery, American Volume | 2006
Andrea E. Buckwalter; John J. Callaghan; Steve S. Liu; Douglas R. Pedersen; Devon D. Goetz; Patrick M. Sullivan; Jessica A. Leinen; Richard C. Johnston
UNLABELLED The current study was performed to determine the status, at a minimum of twenty-five years, of a prospective, single-surgeon series of patients treated with primary Charnley total hip arthroplasty with a contemporary femoral cementing technique that included use of a distal cement plug and a retrograde cement-delivery system. Since our review at a minimum of twenty years postoperatively, two primary total hip prostheses were revised (one because of acetabular loosening, and one because of femoral loosening). Of the original cohort of 357 hips (320 patients), ten (2.8%) had revision of the femoral stem because of aseptic loosening. Forty-nine patients (fifty-two hips, 14.6%) who had been in the initial study group were still living at the time of the present review. Five hips (10%) in living patients had required a femoral revision because of aseptic loosening. Including those that were revised, eight femoral components (17%) in living patients were seen to be loose radiographically. Although this study demonstrates the remarkable durability of the femoral fixation obtained with the polished flatback Charnley prosthesis and the contemporary cementing technique, there was some deterioration of the results with time. These results provide a standard for comparison with cementless fixation after hips treated with that technique have been followed for a similar duration. LEVEL OF EVIDENCE Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.
Journal of Bone and Joint Surgery, American Volume | 2008
John J. Callaghan; Steve S. Liu; Daniel E. Firestone; Tameem M. Yehyawi; Devon D. Goetz; Jason Sullivan; David A. Vittetoe; Michael R. O'rourke; Richard C. Johnston
BACKGROUND In the mid- to late 1970s, on the basis of laboratory and finite element data, many surgeons in the United States began using collared matte-finish femoral components and metal-backed acetabular components in their total hip arthroplasties. The purpose of this study was to evaluate the long-term results of the use of one such construct in arthroplasties performed by a single surgeon in a consecutive nonselected patient cohort. METHODS Between January 1984 and December 1985, 273 patients underwent a total of 304 consecutive nonselected total hip arthroplasties with cement and use of the Iowa femoral component (which is collared, has a proximal cobra shape, and has a matte finish) and a metal-backed TiBac acetabular component performed by a single surgeon. At nineteen to twenty years postoperatively, only two patients (two hips) were lost to follow-up. For clinical evaluation, we attempted to interview all living patients and the families of the patients who had died to verify the status of the hip prosthesis or any revisions. Radiographic evaluation consisted of analysis for loosening and osteolysis as well as wear of the acetabular component. RESULTS At the time of the nineteen to twenty-year follow-up, the rate of revision of the arthroplasty for any reason was 10.5% (thirty-two hips) for all patients and 25% (twenty-three hips) for living patients. The rate of revision due to aseptic femoral loosening was 2.6% (eight hips). There was radiographic evidence of loosening of the femoral component in fifteen hips (4.9%), including those that were revised, and femoral osteolysis was seen distal to the trochanters in twenty-two hips (7.2%). The rate of revision due to aseptic loosening of the acetabular component was 7.9% (twenty-four hips), and there was radiographic evidence of acetabular loosening in forty-two hips (13.8%), including those that were revised. CONCLUSIONS This study demonstrates the durability of a cemented matte-finish collared femoral component at twenty years postoperatively, with a rate of revision due to aseptic loosening of 2.6%. The metal-backed acetabular component also performed well in many patients, with a 7.9% rate of revision due to aseptic loosening. However, in the living patients, the rate of loosening of the acetabular component, including cases revised because of aseptic loosening, was 30.4%.
Journal of Bone and Joint Surgery, American Volume | 2007
Daniel E. Firestone; John J. Callaghan; Steve S. Liu; Devon D. Goetz; Patrick M. Sullivan; David A. Vittetoe; Richard C. Johnston
BACKGROUND Recent studies have suggested that cemented femoral components with a polished surface may provide superior long-term fixation when compared with femoral components with a roughened surface. The purpose of this study was to evaluate the results of total hip arthroplasty with a cemented femoral component with a polished surface finish and compare them with the results of total hip arthroplasty performed with a similar design of cemented femoral component with a rougher surface finish. METHODS We retrospectively reviewed a consecutive group of 132 patients (149 hips) in whom primary total hip arthroplasty had been performed by one surgeon using a cemented collared femoral component with a polished (0.1-microm Ra) surface finish and a cementless acetabular component. Ninety-eight patients (115 hips) were followed for a minimum of ten years. We compared the survivorship of this prosthesis with that of a femoral component of similar design but with rougher surfaces (matte or grit-blasted). RESULTS No polished stems were revised because of aseptic loosening or demonstrated radiographic evidence of loosening; however, eight hips (5.4%) with a polished stem demonstrated osteolysis distal to the greater or lesser tro-chanter. In contrast, six stems (2.0%) with a matte surface finish of 0.8-microm Ra were revised because of aseptic loosening, and an additional five stems were seen to be loose radiographically. Eleven stems (9.2%) with a grit-blasted surface finish of 2.1-microm Ra were revised because of aseptic loosening, and an additional four stems were seen to be loose radiographically. The difference in the prevalence of revision due to aseptic loosening between the group with the 0.1-microm Ra surface and the group with the 2.1-microm Ra surface was significant (p = 0.001), as was the difference between the prevalence of revision due to aseptic loosening between the group with the 0.8-microm Ra surface and the group with the 2.1-microm Ra surface (p = 0.001). No cups were revised because of aseptic loosening, and one hip had radiographic signs of acetabular loosening. CONCLUSIONS This study demonstrated excellent durability of a prosthesis consisting of a cemented, collared, polished femoral component and a cementless acetabular component. While no hips were revised because of aseptic loosening, distal femoral osteolysis was observed in eight hips (5.4%), a higher prevalence than has been reported by others after similar durations of follow-up of tapered, collarless, polished femoral components.
Journal of Bone and Joint Surgery, American Volume | 2012
Ryan K. Takenaga; John J. Callaghan; Nicholas A. Bedard; Steve S. Liu; Alison L. Klaassen; Douglas R. Pedersen
BACKGROUND The durability of total hip arthroplasty in younger patients has been reported to be less than that in older patients. The purpose of this study was to evaluate the results of cementless total hip arthroplasty performed in a consecutive series of patients fifty years of age or younger who were followed for a minimum of ten years. METHODS We prospectively followed 100 consecutive patients (115 hips) who were fifty years of age or younger when they were treated with primary cementless total hip arthroplasty with use of a second-generation, extensively porous-coated femoral stem and a cementless acetabular component. The patients were followed for a minimum of ten years, and the results were compared with our patients in the same age group who had total hip arthroplasty with cement. Evaluation included the need for revision, activity questionnaires, six-minute walks, activity level monitoring with an accelerometer, and radiographic evaluation for evidence of loosening, wear, and osteolysis. RESULTS Seventy-three patients (eighty-two hips) were available for follow-up at ten years (mean, twelve years). Seventeen patients (twenty-three hips) had died, and ten patients (ten hips) were lost to follow-up. The average age at the time of surgery was 40.1 years. Three femoral stems were revised for periprosthetic fracture. No acetabular shell or femoral stem was revised for loosening, and none were loose on radiographs made at the time of a minimum ten-year follow-up. This compares favorably with the cemented cohort, which had poorer survivorship of the implant with regard to revision for aseptic loosening and radiographic loosening. Reoperation for any reason was similar between the two cohorts at ten years, primarily because of the relatively large numbers of revisions for polyethylene wear in the cementless group. CONCLUSIONS Cementless total hip arthroplasty with use of a second-generation, extensively porous-coated stem demonstrated durable fixation in an active, younger population at a minimum follow-up of ten years and had better survivorship with respect to fixation compared with our previously reported cemented cohort.
Journal of Arthroplasty | 2013
Nicholas A. Bedard; John J. Callaghan; Steve S. Liu; Justin J. Greiner; Alison L. Klaassen; Richard C. Johnston
Results of cementless THA for osteonecrosis were evaluated at a minimum of 10-year follow-up and compared to our previous report of cemented THA for osteonecrosis. Eighty cementless THAs in 66 patients with osteonecrosis were followed for a minimum of 10 years. Evaluation consisted of need for revision; radiographic evidence of loosening, wear and osteolysis; activity monitoring with an accelerometer; UCLA, Tegner, WOMAC, and Harris hip scores. Results were compared to 48 cemented THAs performed for osteonecrosis with comparable follow-up. At a minimum of 10 years, 10 hips required reoperation. Loosening and revision for loosening were significantly lower in the cementless group compared to the cemented historical control. Cementless fixation in THAs for osteonecrosis demonstrated durable results with bearing surface wear being the major long-term problem.