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The long-term failure modes of total hip arthroplasty (THA) in adult patients who had childhood infection have not been documented. The purpose of this study is to analyze the longer term clinical and radiographic results, prevalence of osteolysis, and survival rate of THA.We reviewed the results of 142 patients (145 hips) (mean age 41.9 years). The age of the patients at the time that the infection was contracted was an average of 7.1 years (range 1-11). The average interval between active infection and THA was 34.5 years. All but 2 hips (1 patient) had a quiescent period of infection of more than 10 years. The average duration of follow-up after THA was 31.5 years (range 25-38).All but 2 hips with more than 10 years of quiescent infection had no recurrence of infection. The remaining 2 hips in the 1 patient with only 7 years of quiescent infection had a recurrence of infection. Seventy-eight of 145 hips (54%) underwent isolated cup revision for loosening, or osteolysis, or dislocation. Thirty (21%) femoral components were revised for aseptic loosening and/or osteolysis. The Kaplan-Meier survivorship curve at 31.5 years showed that the survival rate of the acetabular component was 46% (95% confidence interval 39-74) and that of the femoral component was 79% (95% confidence interval 73-89).Contributing factors to the high failure rate of THAs were less than optimal prostheses and poor quality of polyethylene during the time period of this study.

Total hip arthroplasty (THA) among octogenarians presents greater challenges than among the younger patient population because of the high risk of perioperative morbidity and mortality and poor bone quality. We determined the clinical performance and radiographic results of an ultrashort, proximally porous-coated and tapered metaphyseal-fitting cementless femoral stem for octogenarians. A total of 100 unselected octogenarians (112 hips) were included in this retrospective study. All patients received the ultrashort, proximally porous-coated and tapered cementless stem during the study period, but patients who could not walk preoperatively were excluded from the analysis. Their mean age was 82.3±12.1 years (range, 80–92 years). Assessment was performed with the Harris Hip Score; Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score; thigh pain; University of California, Los Angeles (UCLA) activity score; and radiographic results. The mean duration of follow-up was 7.6 years (range, 6–9 years). At the final follow-up, the mean Harris Hip Score was 87±13 points, the mean WOMAC score was 26±8 points, and the mean UCLA activity score was 4.5 points. Osseointegration was obtained for 105 (94%) acetabular components and 110 (98%) femoral components. Kaplan-Meier survivorship analysis at 9 years showed that the survival rate for the acetabular component was 94% (95% CI, 91–98) and that of the femoral component was 98% (95% CI, 91–100), with aseptic loosening or revision as the end point. The ultrashort cementless femoral component provides stable fixation without the need for diaphyseal fixation among octogenarians. [ Orthopedics . 2022;45(3):181–186.]

Background The purpose of this study is to determine the long-term (up to 27 years) results of a modified technique applying strut allografts combined with a reduction osteotomy over an extensively porous-coated stem. Methods We reviewed the results of 399 revision total hip arthroplasties (for aseptic loosening in 390 hips and septic loosening in 9 hips) in 369 patients (mean age 58 ± 13 years, range 22-65) performed with an extensively porous-coated femoral stem combined with a cortical strut onlay allograft. The mean follow-up was 23 years (range 20-27). Results The mean Harris Hip Score was 84 ± 16 points (range 35-100) at the final follow-up. The mean Western Ontario and McMaster Universities Osteoarthritis Index score was 21 ± 16 points (range 12-53) at the final follow-up. The mean University of California Los Angeles activity score was 6.1 points (range 5-8). A Kaplan-Meier survivorship analysis at 23 years of follow-up showed that the survival rate of the femoral component was 95.5% (95% confidence interval 89-98) with aseptic loosening or revision for any reason and it was 91.5% (95% confidence interval 85-95) if septic loosening was included. Conclusion We found good results in terms of longevity and functional outcome using this modified technique. Future mechanical studies in addition to controlled clinical studies are warranted.

There are no reported results for more than 20 years of a pure proximal-loading anatomic cementless femoral stem without diaphyseal stem fixation. The purpose of this study was to evaluate the long-term (minimum 20 years) clinical results, bone remodeling, revision rate, and survivorship of these implants in patients aged less than 60 years.We included 523 patients (657 hips), including 319 men and 204 women. The mean body mass index was 26.7 (range, 23-29 kg/mThe Harris Hip Score at the final follow-up was a mean 93 points (range, 70-100 points). The Western Ontario and McMaster Universities Osteoarthritis Index and University of California, Los Angeles activity scores at the final follow-up were 16 and 7.6 points, respectively. Five femoral components (0.8%) and 13 acetabular components (2.0%) were revised. All cases in the current series had grade 2 stress shielding; no hips had grade 3 or 4 stress shielding. Kaplan-Meier survivorship of the implants at 23.5 years was 98.0% (95% confidence interval 92%-100%) for the acetabular component and 99.2% (95% confidence interval 93%-100%) for the femoral component.A pure proximal-loading metaphyseal-fitting anatomic cementless stem with alumina-on-alumina ceramic bearing couples functioned well, with no osteolysis or mild stress-shielding at an average 23.5-year follow-up.

The rate of failure of cemented and cementless total hip arthroplasty (THA) in younger patients is higher than that in elderly patients. The purpose of this study is to document the long-term clinical results of THA with the so-called third-generation cementing and the results of second-generation cementless THA in patients50 years of age.This study included 106 patients who had had bilateral THA with a cemented stem in one hip and a cementless stem in the other. There were 78 men and 28 women. Their mean age was 47 years (range, 21-49). The average follow-up duration was 31 years (range, 30-32.5).There were similar mean Harris Hip Scores (90 versus 91 points) between the groups at the final follow-up. Forty-six acetabular components (43%) in the cemented group and 48 acetabular components (45%) in the cementless group were revised. Five femoral components (5%) in the cemented group and 4 femoral components (4%) in the cementless group were revised. Survivorship of the acetabular component at 30.8 years was similar in both groups (57% in the cemented group versus 55% in the cementless group). Survivorship of the femoral component at 30.8 years was also similar in both groups (95% in the cemented group versus 96% in the cementless group).Long-term fixation of the cemented or cementless femoral stem was outstanding. There was a high rate of the acetabular component revision due to conventional polyethylene wear and periacetabular osteolysis in both hybrid and fully cementless THA groups.

Background The purpose of this study is to determine the clinical and radiographic outcomes, mortality rate, complication rate, and revision rate of this ultra-short non-anatomic cementless femoral stem in elderly patients with a femoral neck fracture. Methods We reviewed the results of 284 total hip arthroplasties performed with an ultra-short non-anatomic cementless stem in 280 previously active patients with a mean age of 72.8 ± 13 years (range 49-83). The mean follow-up was 9.3 years (range 7-13). Results The mean Harris Hip Score was 86 ± 14 points at final follow-up. The mean Western Ontario and McMaster Universities Osteoarthritis Index score was 24 ± 6 points at the final follow-up. The mean University of California, Los Angeles activity score was 6 points at final follow-up. Osseointegration was seen in all acetabular (100%) and in 276 femoral components (97%). Kaplan-Meier survivorship analysis revealed that the survival rate of the femoral component at 8.3 years was 97% (95% confidence interval 91–100) and that of the acetabular component was 100% (95% confidence interval 94–100) with aseptic loosening or revision as the end point. Conclusion An ultra-short non-anatomic cementless femoral stem in patients with good bone quality (Dorr A and some Dorr type B bone) is a safe treatment for femoral neck fracture. In patients with poor bone quality (Dorr C type), the results were very poor, and use of this stem should be avoided.

Background There is a paucity of studies longer than 30 years to determine clinical and radiographic results of retained cementless anatomic stem. The purpose of this study is to determine the long-term (up to 34 years) survival rate of the retained cementless anatomic femoral stem in patients Methods Isolated cup revision was performed with retaining primary cementless anatomic femoral stem in 206 patients (149 men and 57 women). Clinical and radiographic results were monitored at each follow-up. At the latest follow-up, computed tomography scans were carried out in all hips to determine the prevalence of osteolysis. The mean follow-up of the retained femoral stem was 30.3 years (range 27-34). The mean follow-up of the revised cup was 25.5 years (range 22-29). Results The mean Harris Hip Score was 91 ± 7.8 points (range 71-100) and the mean Western Ontario and McMaster Universities Osteoarthritis score was 16 ± 7 points (range 7-34) at the final follow-up. The mean University of California, Los Angeles activity score was 7 ± 4 points (range 5-10) at the final follow-up. The overall survival rate of retained cementless femoral stems was 98.9% (95% confidence interval 91-100) at 30.3 years. The survival rate of the revised cup was 93% (95% confidence interval 89-98) at 25.5 years. Conclusion The rate of aseptic loosening of already osseointegrated femoral stem remains low with ceramic-on-ceramic bearing in young active patients.

Background Despite cementless total knee arthroplasties (TKAs) have potential advantages over cemented TKAs, there are conflicting results. The purpose of the present study is to determine the long-term clinical and radiographic results, the survival rate, and the prevalence of osteolysis of cemented vs cementless TKAs. Methods A total of 261 patients (522 knees) who underwent bilateral simultaneous TKAs were included in the present study (mean age, 62.5 ± 5.5 years). Patients were evaluated clinically, radiographically, and also using computed tomography scans. A mean follow-up period was 23.8 years (range, 22-25 years). Results There were no significant differences between the Knee Society total score, change in total score, knee function score, and Western Ontario and McMaster Universities Osteoarthritis Index score in the 2 groups. In total, 8 knees (3%) were revised in the cementless group and 5 knees (2%) in the cemented group. Radiographs and computed tomography scans showed no femoral, tibial, or patellar osteolysis in either group. The rate of survival at 25 years was 97% (95% confidence interval [CI], 92%-100%) in the cementless group and 98% (95% CI, 94%-100%) in the cemented group, with reoperation for any reason as the end point. The rate of survival at 25 years was 98% (95% CI, 94%-100%), with reoperation for aseptic loosening as the end point in both groups. Conclusions At this length of follow-up, cementless TKA has comparable outcomes and survivorship to cemented TKA.

Background There are conflicting reports of early and mid-term results of the high-flexion total knee arthroplasties (TKAs). The purpose of the present long-term follow-up study was to determine the long-term (minimum 20 years) clinical and radiographic and CT scan results, and the survival rates of high-flexion versus standard TKAs. Methods Ninety-five patients (190 knees) were included (mean age, 65 ± 6.5 years). The mean follow-up was 20.3 years (range, 20 to 20.6 years). Results Revision of the TKA was performed in 5 knees (5.2%) with high-flexion TKA and in 3 knees (3.2%) with standard TKA. The rate of survival at 20 years was 94.8% (95% CI, 91%-98%) in the high-flexion TKA group and 96.8% (95% CI, 92%-100%) in the standard TKA group with reoperation for any reason. No knee had osteolysis in either group. Conclusions At this length of follow-up, high-flexion TKA has comparable outcomes and survivorship to standard TKA.

Application of highly cross-linked polyethylene (HXLPE) to a posterior cruciate-substituting total knee arthroplasty (TKA) might add the risk of fracture and failure of the tibial polyethylene insert. The purpose of this study is to evaluate the long-term (up to 19 years) clinical and radiographic results of posterior cruciate-substituting TKAs with HXLPE or conventional polyethylene.This study analyzed the results of 1,217 patients (444 men and 773 women; mean age of 65 ± 7 years, range, 31-85) (2,434 knees) who had received a NexGen LPS-Flex prosthesis with a conventional tibial insert in one knee and the same prosthesis with an HXLPE tibial insert in the contralateral knee. The mean duration of follow-up was 17 years (range, 15-19).The 2 groups did not differ significantly (P.05) with regard to the clinical and radiographic results. No knee in either group had a fracture of the tibial polyethylene post or failure of the locking mechanism of the tibial polyethylene insert or osteolysis. Twenty-eight knees (2.3%) in the HXLPE group and 26 knees (2.1%) in the conventional polyethylene group were revised. The estimated survival rate at 17 years was 97.7% in the HXLPE group and 97.9% in the conventional polyethylene group.The data suggest that clinical and radiographic findings at a mean of 17 years after posterior cruciate-substituting TKA are the same for patients treated with HXLPE and those treated with conventional polyethylene.

The purpose of this long-term (up to 17 years) follow-up study was to determine: (1) clinical results and evidence of clicking or squeaking sounds; (2) radiographic results, including rates of osseointegration, bone remodeling, and osteolysis; (3) rates of complications including thigh pain, periprosthetic fracture, and ceramic fracture; (4) rates of revision; and (5) survival rates of implants in patients younger than 30 years.We analyzed the results of 240 consecutive primary total hip arthroplasty in 180 patients (118 men and 62 women who had a mean age of 27 years (range, 21 to 30 years)). The mean follow-up was 16 years (range, 14 to 17 years).Mean Harris hip score, Western Ontario and McMaster Universities score, and University of California, Los Angeles activity score were 93 points, 18 points, and 7 points, respectively, at final follow-up. Radiographically, all of the acetabular components and all but two femoral components were well-fixed at the final follow-up. No hip had osteolysis or exhibited Grade 3 stress shielding. All but two patients had no groin or thigh pain. No hip had a periprosthetic or ceramic fracture. Eight hips (3%) exhibited squeaking sounds. Two acetabular components and two femoral stems were revised. The survival of the acetabular and femoral component was 99.2% (95% confidence interval, 94 to 100%).The results of the present long-term study of ultra-short anatomic cementless femoral stems suggest excellent clinical and radiographic results in patients younger than 30 years.

Background This study compares the long-term functional, radiographic, and computed tomography scan outcomes and implant survivorship of ceramic-on-ceramic total hip arthroplasty (C-O-C THA) and ceramic-on-highly cross-linked polyethylene total hip arthroplasty (C-O-HXLPE THA) in the same patients. Methods In this randomized, prospective trial conducted between January 1999 and April 2003, 133 patients (266 hips) younger than 55 years were enrolled. Each patient received C-O-C THA in 1 hip and a C-O-HXLPE THA in the other. The mean follow-up was 17.1 years (range, 15-18 years); there were 84 men and 49 women with a mean age of 53 ± 7 years (range, 25-55 years). Results At the latest follow-up, mean Harris hip scores (94 vs 93 points; P = .861), pain scores (43 vs 42 points; P = .651), and patient satisfaction scores (7.8 vs 7.6 points; P = .379) were not different between the 2 groups. Eight hips (3%) in the C-O-C THA had an audible squeaking sound. The mean annual penetration rate of HXLPE was 0.0162 ± 0.032 mm per year. No osteolysis was recorded on radiographs or computed tomography scans in either group. At 17.1 years, the survival rate of the acetabular component was 97% in the C-O-C bearing group and 98% in the C-O-HXLPE bearing group (P = .923). The survival rate of the femoral component was 99% in both groups. Conclusion Both C-O-C THA and C-O-HXLPE THA functioned well, with no osteolysis at mean of 17.1-year follow-up.

To insert the regular-sized stem for a dysplastic femoral canal, controlled episiotomy of the femur can be performed. The purpose of this study is to determine the long-term (up to 19 years) results of total hip arthroplasties (THAs) using strut allografts combined with an episiotomy over an extensively porous-coated stem.We reviewed the results of 65 total hip arthroplasties in 63 patients (mean age 42.1 years; range 21-61) with dysplastic femur after childhood sepsis. The patients were treated using controlled episiotomy of the femur to widen the femoral canal, extensively porous-coated femoral stems, and cortical strut allografts because primary axial or rotational stability could not be achieved without grafting. The mean follow-up was 17.1 years (range 15-19).The mean Harris Hip Score at the final follow-up was 85 ± 15 points (range 45-100). The mean Western Ontario and McMaster Universities Osteoarthritis Index score was 23 ± 15 points (range 13-53). The mean University of California, Los Angeles score was 6.3 points (range 5-8). A Kaplan-Meier survivorship analysis at 19 years of follow-up showed that the survival rate of the femoral components was 92% (95% confidence interval 89-98), and it was 88% (95% confidence interval 85-92) for the acetabular component with aseptic loosening or revision for any reason.We found good results in terms of longevity and functional outcome using this technique. Future mechanical studies, in addition to controlled clinical studies, are warranted.

Background The aim of this study is to assess the long-term outcomes of this specific stem in patients younger than 50 years old, with regard to clinical and radiographic outcomes, survivorship, and complication rate. Methods Two hundred thirty-nine consecutive series of patients (324 hips) who were younger than 50 years old at the time of surgery were enrolled in the study. Osteonecrosis (50%) and dysplastic hip (34%) were most common diagnoses. Patients were informed to use crutches or walker for 4 weeks to protect the femoral component against rotational stress. The mean follow-up was 15.6 years (range 14-17). Results At the latest follow-up, the mean Harris Hip Score, Western Ontario and McMaster Universities Osteoarthritis Index score, and University of California, Los Angeles activity score were 93 points, 13 points, and 7 points, respectively. Three patients (1.3%) had moderate thigh pain. All of the acetabular components and 321 (99%) femoral stems were solidly fixed at the time of the latest follow-up. Three stems (0.9%) were revised for aseptic loosening. Two hips (0.6%) had a dislocation and 2 hips (0.6%) had a periprosthetic fracture. Ceramic fracture or osteolysis was not found in any hip at the time of the final follow-up. Survival rate of the femoral component was 99.1% (95% confidence interval 94-100) and that of the acetabular component was 100% (95% confidence interval 94-100) at 15.6 years. Conclusion In this series, THA using an ultra-short metaphyseal-fitting anatomic cementless femoral stem provided excellent long-term clinical and radiographic results in patients younger than 50 years old. Furthermore, our initial theoretical concerns about early aseptic loosening due to the absence of distal stem fixation were not justified.

Background: Robotic-assisted TKA was introduced to enhance the precision of bone preparation and component alignment with the goal of improving the clinical results and survivorship of TKA. Although numerous reports suggest that bone preparation and knee component alignment may be improved using robotic assistance, no long-term randomized trials of robotic-assisted TKA have shown whether this results in improved clinical function or survivorship of the TKA. Questions/purposes: In this randomized trial, we compared robotic-assisted TKA to manual-alignment techniques at long-term follow-up in terms of (1) functional results based on Knee Society, WOMAC, and UCLA Activity scores; (2) numerous radiographic parameters, including component and limb alignment; (3) Kaplan-Meier survivorship; and (4) complications specific to robotic-assistance, including pin-tract infection, peroneal nerve palsy, pin-site fracture, or patellar complications. Methods: This study was a registered prospective, randomized, controlled trial. From January 2002 to February 2008, one surgeon performed 975 robotic-assisted TKAs in 850 patients and 990 conventional TKAs in 849 patients. Among these patients 1406 patients were eligible for participation in this study based on prespecified inclusion criteria. Of those, 100% (1406) patients agreed to participate and were randomized, with 700 patients (750 knees) receiving robotic-assisted TKA and 706 patients (766 knees) receiving conventional TKA. Of those, 96% (674 patients) in the robotic-assisted TKA group and 95% (674 patients) in the conventional TKA group were available for follow-up at a mean of 13 (± 5) years. In both groups, no patient older than 65 years was randomized because we anticipated long-term follow-up. We evaluated 674 patients (724 knees) in each group for clinical and radiographic outcomes, and we examined Kaplan-Meier survivorship for the endpoint of aseptic loosening or revision. Clinical evaluation was performed using the original Knee Society knee score, the WOMAC score, and the UCLA activity score preoperatively and at latest follow-up visit. We also assessed loosening (defined as change in the position of the components) using plain radiographs, osteolysis using CT scans at the latest follow-up visit, and component, and limb alignment on mechanical axis radiographs.To minimize the chance of type-2 error and increase the power of our study, we assumed the difference in the Knee Society score to be 5 points to match the MCID of the Knee Society with power of 0.99, which revealed that a total of 628 patients would be needed in each group. Results: Clinical parameters at the latest follow-up including the Knee Society knee scores (93 ± 5 points in the robotic-assisted TKA group versus 92 ± 6 points in the conventional TKA group [95% confidence interval 90 to 98]; p = 0.321) and Knee Society knee function scores (83 ± 7 points in the robotic-assisted TKA group versus 85 ± 6 points in the conventional TKA group [95% CI 75 to 88]; p = 0.992), WOMAC scores (18 ± 14 points in the robotic-assisted TKA group versus 19 ± 15 points in the conventional TKA group [95% CI 16 to 22]; p = 0.981), range of knee motion (125 ± 6° in the robotic-assisted TKA group versus 128 ± 7° in the conventional TKA group [95% CI 121 to 135]; p = 0.321), and UCLA patient activity scores (7 points versus 7 points in each group [95% CI 5 to 10]; p = 1.000) were not different between the two groups at a mean of 13 years' follow-up. Radiographic parameters such as the femorotibial angle (mean 2° ± 2° valgus in the robotic-assisted TKA group versus 3° ± 3° valgus in the conventional TKA group [95% CI 1 to 5]; p = 0.897), femoral component position (coronal plane: mean 98° in the robotic-assisted TKA group versus 97° in the conventional TKA group [95% CI 96 to 99]; p = 0.953; sagittal plane: mean 3° in the robotic-assisted TKA group versus 2° in the conventional TKA group [95% CI 1 to 4]; p = 0.612) and tibial component position (coronal plane: mean 90° in the robotic-assisted TKA group versus 89° in the conventional TKA group [95% CI 87 to 92]; p = 0.721; sagittal plane: 87° in the robotic-assisted TKA group versus 86° in the conventional TKA group [95% CI 84 to 89]; p = 0.792), joint line (16 mm in the robotic-assisted TKA group versus 16 mm in the conventional TKA group [95% CI 14 to 18]; p = 0.512), and posterior femoral condylar offset (24 mm in the robotic-assisted TKA group versus 24 mm in the conventional TKA group [95% CI 21 to 27 ]; p = 0.817) also were not different between the two groups (p > 0.05). The aseptic loosening rate was 2% in each group, and this was not different between the two groups. With the endpoint of revision or aseptic loosening of the components, Kaplan-Meier survivorship of the TKA components was 98% in both groups (95% CI 94 to 100) at 15 years (p = 0.972). There were no between-group differences in terms of the frequency with which complications occurred. In each group, 2% of knees (15) had a superficial infection treated with intravenous antibiotics for 2 weeks. No deep infection occurred in these knees. In the conventional TKA group, 0.8% of knees (six) had a motion limitation (< 60°). Conclusions: At a minimum follow-up of 10 years, we found no differences between robotic-assisted TKA and conventional TKA in terms of functional outcome scores, aseptic loosening, overall survivorship, and complications. Considering the additional time and expense associated with robotic-assisted TKA, we cannot recommend its widespread use. Level of evidence: Level I, therapeutic study.

Background:No study has yet assessed the effect of medial open-wedge high tibial osteotomy (MOWHTO) on the patellofemoral joint according to postoperative alignment.Purpose:To evaluate the effect of MOWHTO on the patellofemoral joint according to postoperative alignment by comparing the cartilage status before and after surgery and assessing the clinical and radiological outcomes.Study Design:Cohort study; Level of evidence, 3.Methods:A total of 135 patients who underwent MOWHTO were retrospectively investigated. The patients were divided into 3 groups according to the postoperative weightbearing line ratio (WBLR): undercorrection (WBLR 66.3%, highest quartile). The postoperative change in the cartilage status was assessed arthroscopically during implant removal at 2 years after MOWHTO. The clinical and radiological outcomes were evaluated at a mean follow-up of 52.1 months. A regression analysis was performed to identify the factors affecting the deterioration of the patellofemoral joint cartilage status. A receiver operating characteristic curve was employed to identify the cutoff point for the postoperative WBLR associated with the deterioration of the cartilage status in the patellofemoral joint.Results:Of all patients, progression of cartilage degeneration was noted in 39.3% for femoral trochlea and 23.7% for patella. The incidence of cartilage progression was significantly higher in the overcorrection group than in the undercorrection and acceptable correction groups (femoral trochlea: undercorrection group = 30.3%, acceptable correction group = 32.4%, and overcorrection group = 61.8% [ P = .008]; patella: undercorrection group = 15.2%, acceptable correction group = 17.7%, and overcorrection group = 44.1% [ P = .005]). The functional outcomes, including Lysholm knee score, Knee injury and Osteoarthritis Outcome Score (Pain, Symptoms, and Activities of Daily Living subscales), and Shelbourne and Trumper score, were significantly worse in the overcorrection group. The regression analysis showed that only the postoperative WBLR had a significant effect on cartilage deterioration. The cutoff point for the postoperative WBLR associated with progression of the International Cartilage Repair Society grade was 62.1% for the femoral trochlea (sensitivity = 61.5%, specificity = 62.7%, accuracy = 66.2%) and 62.2% for the patella (sensitivity = 59.4%, specificity = 60.2%, accuracy = 67.8%).Conclusion:The patellofemoral joint was adversely affected by MOWHTO. Overcorrection causing excessive valgus alignment led to further progression of degenerative changes in the patellofemoral joint and inferior clinical outcomes. The postoperative WBLR can be used as a predictive factor for deterioration of the cartilage status in the patellofemoral joint after MOWHTO.

Robotic-assisted TKA was introduced to enhance the precision of bone preparation and component alignment with the goal of improving the clinical results and survivorship of TKA. Although numerous reports suggest that bone preparation and knee component alignment may be improved using robotic assistance, no long-term randomized trials of robotic-assisted TKA have shown whether this results in improved clinical function or survivorship of the TKA.In this randomized trial, we compared robotic-assisted TKA to manual-alignment techniques at long-term follow-up in terms of (1) functional results based on Knee Society, WOMAC, and UCLA Activity scores; (2) numerous radiographic parameters, including component and limb alignment; (3) Kaplan-Meier survivorship; and (4) complications specific to robotic-assistance, including pin-tract infection, peroneal nerve palsy, pin-site fracture, or patellar complications.This study was a registered prospective, randomized, controlled trial. From January 2002 to February 2008, one surgeon performed 975 robotic-assisted TKAs in 850 patients and 990 conventional TKAs in 849 patients. Among these patients 1406 patients were eligible for participation in this study based on prespecified inclusion criteria. Of those, 100% (1406) patients agreed to participate and were randomized, with 700 patients (750 knees) receiving robotic-assisted TKA and 706 patients (766 knees) receiving conventional TKA. Of those, 96% (674 patients) in the robotic-assisted TKA group and 95% (674 patients) in the conventional TKA group were available for follow-up at a mean of 13 (± 5) years. In both groups, no patient older than 65 years was randomized because we anticipated long-term follow-up. We evaluated 674 patients (724 knees) in each group for clinical and radiographic outcomes, and we examined Kaplan-Meier survivorship for the endpoint of aseptic loosening or revision. Clinical evaluation was performed using the original Knee Society knee score, the WOMAC score, and the UCLA activity score preoperatively and at latest follow-up visit. We also assessed loosening (defined as change in the position of the components) using plain radiographs, osteolysis using CT scans at the latest follow-up visit, and component, and limb alignment on mechanical axis radiographs. To minimize the chance of type-2 error and increase the power of our study, we assumed the difference in the Knee Society score to be 25 points to match the MCID of the Knee Society score with a SD of 5; to be able to detect a difference of this size, we calculated that a total of 628 patients would be needed in each group in order to achieve 80% power at the α = 0.05 level.Clinical parameters at the latest follow-up including the Knee Society knee scores (93 ± 5 points in the robotic-assisted TKA group versus 92 ± 6 points in the conventional TKA group [95% confidence interval 90 to 98]; p = 0.321) and Knee Society knee function scores (83 ± 7 points in the robotic-assisted TKA group versus 85 ± 6 points in the conventional TKA group [95% CI 75 to 88]; p = 0.992), WOMAC scores (18 ± 14 points in the robotic-assisted TKA group versus 19 ± 15 points in the conventional TKA group [95% CI 16 to 22]; p = 0.981), range of knee motion (125 ± 6° in the robotic-assisted TKA group versus 128 ± 7° in the conventional TKA group [95% CI 121 to 135]; p = 0.321), and UCLA patient activity scores (7 points versus 7 points in each group [95% CI 5 to 10]; p = 1.000) were not different between the two groups at a mean of 13 years' follow-up. Radiographic parameters such as the femorotibial angle (mean 2° ± 2° valgus in the robotic-assisted TKA group versus 3° ± 3° valgus in the conventional TKA group [95% CI 1 to 5]; p = 0.897), femoral component position (coronal plane: mean 98° in the robotic-assisted TKA group versus 97° in the conventional TKA group [95% CI 96 to 99]; p = 0.953; sagittal plane: mean 3° in the robotic-assisted TKA group versus 2° in the conventional TKA group [95% CI 1 to 4]; p = 0.612) and tibial component position (coronal plane: mean 90° in the robotic-assisted TKA group versus 89° in the conventional TKA group [95% CI 87 to 92]; p = 0.721; sagittal plane: 87° in the robotic-assisted TKA group versus 86° in the conventional TKA group [95% CI 84 to 89]; p = 0.792), joint line (16 mm in the robotic-assisted TKA group versus 16 mm in the conventional TKA group [95% CI 14 to 18]; p = 0.512), and posterior femoral condylar offset (24 mm in the robotic-assisted TKA group versus 24 mm in the conventional TKA group [95% CI 21 to 27 ]; p = 0.817) also were not different between the two groups (p0.05). The aseptic loosening rate was 2% in each group, and this was not different between the two groups. With the endpoint of revision or aseptic loosening of the components, Kaplan-Meier survivorship of the TKA components was 98% in both groups (95% CI 94 to 100) at 15 years (p = 0.972). There were no between-group differences in terms of the frequency with which complications occurred. In all, 0.6% of knees (four) in each group had a superficial infection, and they were treated with intravenous antibiotics for 2 weeks [corrected]. No deep infection occurred in these knees. In the conventional TKA group, 0.6% of knees (four) had motion limitation (60°) [corrected].At a minimum follow-up of 10 years, we found no differences between robotic-assisted TKA and conventional TKA in terms of functional outcome scores, aseptic loosening, overall survivorship, and complications. Considering the additional time and expense associated with robotic-assisted TKA, we cannot recommend its widespread use.Level I, therapeutic study.

Background The purpose of this study is to compare the long-term clinical and radiographic results, survival rates, and complication rates of an ultra-short vs a conventional length cementless anatomic femoral stem. Methods We reviewed 759 patients (858 hips) (mean age, 56.3 ± 12.9 y) who had an ultra-short cementless anatomic stem and 759 patients (858 hips) (mean age, 54.8 ± 12.3 y) who had a conventional length cementless anatomic stem. The mean follow-up was 16.5 years (range 14-17) in the ultra-short stem group and 17.5 years (range 17-20) in the conventional stem group. Results At the latest follow-up, there were no significant differences between the 2 groups in terms of the Harris Hip Scores (92 ± 6 vs 91 ± 7 points, P = .173), Western Ontario and McMaster Universities Osteoarthritis scores (12 ± 8 vs 13 ± 7 points, P = .972), University of California Los Angeles activity scores (7.6 vs 7.8 points, P = .841), patient satisfaction scores (7.7 ± 2.3 vs 7.5 ± 2.5 points, P = .981), and survival rates (97.6% vs 96.6%). However, incidence of thigh pain (P = .031) and stress shielding (P = .001) was significantly higher in the conventional length stem group than in the ultra-short anatomic stem group. Complication rates were similar (1.8% vs 2.7%) between the 2 groups. Conclusion Although an ultra-short cementless anatomic femoral stem confers equivalent clinical and radiographic outcomes, survival rates, and complication rates to conventional length cementless anatomic stem, the incidence of thigh pain and stress shielding was significantly lower in the ultra-short cementless anatomic stem. Level of Evidence Therapeutic Level I.

Background Our study determined long-term (up to 27 years) results of fixed-bearing vs mobile-bearing total knee arthroplasties (TKAs) in patients Methods This study included 291 patients (582 knees; mean age 58 ± 5 years), who received a mobile-bearing TKA in one knee and a fixed-bearing TKA in the other. The mean duration of follow-up was 26.3 y (range 24-27). Results At the latest follow-up, the mean Knee Society knee scores (91 ± 9 vs 89 ± 11 points, P = .383), Western Ontario and McMaster Universities Osteoarthritis Index (35 ± 7 vs 37 ± 6 points, P = .165), range of knee motion (128° ± 13° vs 125° ± 15°, P = .898), and University of California, Los Angeles activity score (6 ± 4 vs 6 ± 4 points, P = 1.000) were below the level of clinical significance between the 2 groups. Revision of mobile-bearing and fixed-bearing TKA occurred in 16 (5.5%) and 20 knees (6.9%), respectively. The rate of survival at 27 years for mobile-bearing and fixed-bearing TKA was 94.5% (95% confidence interval 89-100) and 93.1% (95% confidence interval 88-98), respectively, and no significant differences were observed between the groups. Osteolysis was identified in 4 knees (1.4%) in each group. Conclusion There were no significant differences in functional outcomes, rate of loosening, osteolysis, or survivorship between the 2 groups.

Despite overall good survivorship and clinical outcomes in the short term after total hip arthroplasty (THA) with use of alumina ceramic-on-highly cross-linked polyethylene (HXLPE) in patients younger than 30 years of age, there is a paucity of long-term data to evaluate the fixation of the components and the prevalence of osteolysis. We reviewed the records of 45 patients (54 hips) who had been included in a previous report to evaluate the long-term functional outcomes as well as radiographic and computed tomographic scan findings (particularly with regard to component fixation and osteolysis) after a mean duration of follow-up of 17.8 years. One femoral stem was revised because of aseptic loosening, and 2 acetabular components were revised because of recurrent dislocation. The survival rate at 17.8 years was 98% for the femoral component and 96% for the acetabular component. LEVEL OF EVIDENCE:: Therapeutic Level IV. See Instructions for Authors for a complete description of level of evidence.

BackgroundPersistent or recurrent infection after two-stage revision total knee arthroplasty (TKA) for the treatment of an infected TKA is a dreaded complication. The purpose of the current study was to determine the ability of a second or third two-stage revision TKA to control infection, evaluate the long-term survivorship of the TKA prosthesis, and measure the functional outcome after a second or third two-stage revision TKA for reinfection.MethodsWe evaluated 63 patients (65 knees) with failed two-stage TKA treated with a second or a third two-stage revision TKA. There were 25 men and 38 women (mean age, 67 ± 10.2 years). The mean follow-up from the time of a second two-stage TKA revision was 15.1 years (range, 10 to 19 years) and the mean follow-up from the time of a third two-stage TKA revision was 7 years (range, 5 to 10 years).ResultsOverall, infection was successfully controlled in 49 (78%) of 65 knees after a second two-stage revision TKA was performed. In the remaining 16 knees, recurrent infection was successfully controlled in 12 knees (75%) after a third two-stage revision TKA. Survivorship, free of implant removal for recurrent infection, was 94% at 15.1 years (95% CI, 91 to 100%). Survival free of revision TKA for mechanical failure was 95% (95% CI, 92 to 100%).ConclusionsThe results of the current study suggest that a second or a third two-stage revision TKA is a reasonable option for controlling infection, relieving pain, and achieving a satisfactory level of function for patients with infected TKAs.

In our original report, 97 patients (114 knees) underwent revision total knee arthroplasty with use of a Legacy Constrained Condylar Knee prosthesis (LCCK; Zimmer), with a mean follow-up of 7.2 years (range, 5 to 10 years). The purpose of the present study was to determine the long-term clinical and radiographic results, with a focus on component fixation and the prevalence of osteolysis. At a mean follow-up of 19.2 years (range, 16 to 21 years), re-revision of the LCCK prosthesis had been performed in 10 knees (9%). The rate of survival at 19.2 years was 96% (95% confidence interval [CI], 94% to 100%) with reoperation for mechanical failure as the end point, and 91% (95% CI, 87% to 98%) with reoperation for any reason as the end point. One knee had circumferential osteolysis around the components. LEVEL OF EVIDENCE:: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The purpose of this study was to assess (1) the prevalence of the fracture of ceramic heads implanted on used trunnions of well-fixed stems without using a titanium adapter sleeve; (2) the prevalence of trunnionosis secondary to fretting and/or corrosion at the trunnion of the well-fixed stem; and (3) clinical and radiographic results and the survival rate of the revised acetabular components. Eighty-eight patients (100 hips) underwent isolated revision of the acetabular components for polyethylene wear and osteolysis of the acetabulum. The study group consisted of 70 men and 18 women with a mean age of 52.8 years (range, 31–54 years) when the primary total hip arthroplasty was performed. Evidence of fretting and corrosion of the trunnion of all prostheses was examined macroscopically using a magnifying lens. Degree of fretting and corrosion of the trunnion was assessed using a 4-point scoring technique. A new 36-mm alumina delta ceramic head was implanted on the trunnion of a well-fixed stem without using a titanium adapter sleeve in all hips. The mean follow-up after revision of the acetabular component was 12.8 years (range, 10–14 years). Among the 100 new ceramic heads implanted on a well-fixed stem, no fracture of the ceramic head occurred at a mean follow-up of 12.8 years. The median fretting and corrosion scores for the trunnions were 1.5±1.1 and 1.3±0.9 points, respectively. The mean Harris hip score at the final follow-up was 89±15 points (range, 63–100 points). Survivorship of the revised acetabular components at 14 years was 95% (95% confidence interval, 87.6%–98.6%). [ Orthopedics . 2018; 41(3):158–163.]

Background Methods to reduce the revision rate of total knee prostheses because of wear-related issues are important to examine, particularly because younger patients have a disproportionately high risk of revision. Questions/purposes (1) Are long-term Knee Society knee and function scores better in younger patients with an oxidized zirconium (OxZr) TKA compared with those with a cobalt-chrome (CoCr) TKA? (2) Are there differences in radiographic signs of loosening or CT findings of osteolysis between OxZr TKAs and CoCr TKAs? (3) Are there fewer polyethylene wear particles in the OxZr TKA than CoCr TKA? (4) Do the groups differ in terms of survivorship free from revision surgery at 13 years? Methods From April 2003 to January 2007, we enrolled 110 patients younger than 55 years of age in this randomized, double-blind, prospective trial. Each patient served as his or her own control and each received an OxZr femoral component in one knee and a CoCr femoral component in the other. The minimum followup was 10 years (mean, 13 years; range, 10-14 years); two died and nine were lost to followup before that time, leaving 99 patients (198 knees) for analysis. There were 28 men and 71 women with a mean age of 53 ± 6 years (range, 40-55 years). We obtained Knee Society knee scores for each knee, but Knee Society function scores, WOMAC scores, and UCLA activity scores were obtained for each patient preoperatively and at each followup. Additionally, we performed radiographic examination preoperatively and at each followup. At a minimum of 10 years (mean, 13 years) followup, we obtained CT scans in all patients. Polyethylene wear particles in the synovial fluid were analyzed at the final followup using thermogravimetric methods and scanning electron microscopy. Survivorship was ascertained using the Kaplan-Meier calculator. A sample size calculation determined that to detect a difference in the Knee Society knee score of 5 points, assuming a SD of 5 points, with an α = 0.05 and β = 0.80, a total of 90 patients would be needed in each group. Results At the most recent followup, the mean Knee Society knee scores (92 versus 93 points; p = 0.857), function scores (85 versus 85 points; p = 1.000), WOMAC scores (23 versus 23 points; p = 1.000), UCLA activity scores (6.5 versus 6.5 points; p = 1.000), and range of knee motion (125° versus 127°; p = 0.365) were not different between the two groups. There was no radiographic evidence of loosening and no osteolysis visible on CT scan in either group. The weight of polyethylene wear particles produced at the bearing surface was 0.046 ± 0.010 g in 1 g of synovial fluid in patients with an OxZr femoral component and 0.0448 ± 0.0108 g in patients with a CoCr femoral component (p = 0.583). Kaplan-Meier survivorship free from revision was 97% for the OxZr group (95% confidence interval [CI], 93-100) and 98% for the CoCr group (95% CI, 93-100) at 13 years after surgery (p = 0.918). Conclusions Given the absence of demonstrated superiority of either the CoCr implant or the OxZr implant, we recommend that surgeons and healthcare systems can reasonably choose the less expensive device for routine use, unless there is some compelling reason in an individual patient to choose one over the other (such as severe, documented metal sensitivity). Level of evidence Level I, therapeutic study.

BACKGROUND Question arises as to whether rigid fixation of ultra-short anatomic or ultra-short non-anatomic proximal loading uncemented femoral stem can be obtained without diaphyseal stem fixation. The purpose of this study is to compare the short-term clinical results, radiographic results, revision and survival rates, and complication rates of ultra-short anatomic versus ultra-short non-anatomic uncemented femoral stems. METHODS This study consisted of 50 patients (56 hips) in the ultra-short anatomic uncemented stem group (mean age 61.4 ± 14.7 years) and 50 patients (56 hips) in the ultra-short non-anatomic uncemented stem group (mean age 59.5 ± 15.2 years). The mean follow-up was 3.4 years (range 3-4) in the ultra-short anatomic stem group and 3.5 years (range 3-4) in the ultra-short non-anatomic stem group. RESULTS At the final follow-up, the mean Harris hip scores (92 vs 93 points), Western Ontario and McMaster Universities Osteoarthritis scores (16 vs 15 points), University of California at Los Angeles activity scores (6.5 vs 6.8 points), the incidence of thigh pain (0% vs 4%), revision rates (0% vs 4%), aseptic loosening rate (0% vs 2%), and complication rates (2% vs 4%) were not significantly different between 2 groups. CONCLUSION Both ultra-short anatomic and ultra-short non-anatomic proximal loading uncemented femoral stems obtained rigid fixation without diaphyseal stem fixation in the short-term follow-up. This finding suggests that an ultra-short anatomic uncemented femoral stem can be replaced with an ultra-short non-anatomic uncemented stem to reduce inventory of the femoral stems, and consequently reduce manufacturing and delivery cost of these femoral stems.

To ascertain whether tranexamic acid reduces the blood loss and transfusion rate and volumes; increase the prevalence of deep vein thrombosis (DVT); and investigate factors associated with DVT in patients undergoing primary bilateral total knee arthroplasties (TKAs) without use of chemical thromboprophylaxis. There were 874 patients (1748 knees) in the control group who did not receive tranexamic acid and 871 patients (1742 knees) in the study group who received tranexamic acid. Mechanical compression device was applied without any chemical thromboprophylaxis. Transfusion rates and volumes were recorded. DVT was diagnosed using both sonogram and venogram at 7 or 8 day post-operatively. Intra- and post-operative blood loss and transfusion volumes were significantly lower in the tranexamic acid group. The prevalence of DVT was 14% (245 of 1748 knees) in the control group and 18% (314 of 1742 knees) in the tranexamic acid group. Pre- and post-operative perfusion lung scans revealed no evidence of PE in any patients in either group. Coagulation or thrombophilic data or molecular genetic testing was not significantly different between the two groups. The use of tranexamic acid reduces the volume of blood transfusion and does not increase the prevalence of DVT or PE in the patients who did not receive routine chemical thromboprophylaxis after primary bilateral simultaneous sequential TKAs in Asian patients.

Background The purpose of our prospective, randomized, long-term investigation is to compare the aseptic loosening rate of the femoral component of the total knee prosthesis and clinical and radiographic results of high-flexion posterior cruciate-substituting knee prosthesis or standard posterior cruciate-substituting knee prosthesis in the same patients. Methods There were 960 patients (mean age 71.3 years). The mean follow-up period was 13.2 years (range 10-14). The patients were assessed clinically and radiographically with rating systems of the Knee Society. Furthermore, Western Ontario and McMaster Universities Osteoarthritis questionnaire and ranges of knee motion were determined in both groups. Results In the high-flexion knee group, 2 knees (0.2%) had aseptic loosening of both femoral and tibial components. In the standard knee group, 2 knees (0.2%) had aseptic loosening of the femoral component only. The mean postoperative knee scores (97 vs 97 points), Western Ontario and McMaster Universities Osteoarthritis scores (19 vs 19 points), and range of knee motion (128° vs 129°) were not significantly different between the 2 groups. Two knees (0.2%) in the high-flexion knee group underwent a revision of both femoral and tibial components and 2 knees (0.2%) in the standard knee group had a revision of the femoral component only. Conclusion After a mean of 13.2 years of follow-up, this study did not show increased incidence of femoral component loosening in the high-flexion knee group. Furthermore, we found no significant differences between the 2 groups with regard to clinical or radiographic parameters or range of knee motion.

Background As previous studies are limited to short-term clinical data on conventional and high-flexion total knee arthroplasties (TKAs), long-term clinical data on these TKAs remain unclear. Therefore, we evaluated long-term functional outcome, range of knee motion, revision rate, implant survival, and the prevalence of osteolysis after conventional and high-flexion TKAs in the same patients. Methods The authors evaluated a cohort of 1206 patients with a mean age of 65.3 ± 7 years (range: 22-70) who underwent bilateral simultaneous sequential TKAs. One knee received a conventional TKA and the other received a high-flexion TKA. The mean duration of follow-up was 15.6 years (range: 14-17). Results No significant differences were found between the 2 groups at the latest follow-up with respect to Knee Society score (93 vs 92 points, P = .765), pain score (45 vs 44 points, P = .641), range of knee motion (125° vs 126°, P = .712), and radiographic and computed tomography scan results. Furthermore, no significant revision rate differences were found between the 2 groups (1.3% for conventional TKA vs 1.6% for high-flexion TKA; P = .137). There was no osteolysis recorded in either group. The rate of survivorship free of implant revision or aseptic loosening was 98.7% (95% CI = 91-100) for conventional TKA and 98.4% (95% CI = 91-100) for high-flexion TKA at 17 years. Conclusion At the latest follow-up, we were not able to demonstrate any significant difference between conventional and high-flexion TKAs with respect to functional outcome scores, range of knee motion, revision rate, implant survival, and prevalence of osteolysis.

Background Long-term result of the ultra-short anatomic cementless stem in the patients with idiopathic or ethanol-induced osteonecrosis of the femoral head has not been assessed. The aim of this study is to evaluate the long-term clinical, radiographic, computed tomography scan, and dual-energy X-ray absorptiometry scanning results, and survivorship of this specific femoral stem in patients with idiopathic or ethanol-induced femoral head osteonecrosis. Methods Two hundred fifty-six patients (335 hips) with an average age of 49.8 years (range 20-63) were enrolled in the current study. All patients underwent dual-energy X-ray absorptiometry scanning of the acetabulum and proximal femur preoperatively and at final follow-up. Computed tomography scan was obtained in all patients at final follow-up. The mean follow-up was 14.7 years (range 13-16). Results At final follow-up, the average Harris hip score, Western Ontario and McMaster Universities Osteoarthritis Index score, and University of California, Los Angeles activity score were 94 points, 12 points, and 8 points, respectively. Four stems (1%) underwent revision for aseptic loosening. One acetabular component (0.3%) was revised for recurrent dislocation. No hip was revised for squeaking or clicking sound. Survivorship of the femoral stem was 99.0% (95% confidence interval 94-100) and that of the acetabular component was 99.4% (95% confidence interval 95-100) at 14.7 years. Conclusion Ultra-short proximal loading anatomic uncemented femoral stems with ceramic-on-ceramic bearings have excellent survivorship free from aseptic loosening and good clinical results at long term. Level of Evidence Level IV

No study has compared the prevalence of fretting and corrosion at the trunnion of cobalt-chrome (Co-Cr) and zirconia ceramic heads in the same patients. The authors sought to compare the prevalence of fretting and corrosion at the trunnion after total hip arthroplasty with a 32-mm Co-Cr or a 32-mm zirconia ceramic head-on-polyethylene bearing. Isolated revision of the ace-tabular components was performed in 78 patients (156 hips) for polyethylene wear and osteolysis of the acetabulum. Seventy-eight Co-Cr head–titanium alloy stem pairs were compared with 78 zirconia ceramic head–titanium alloy stem pairs in the same patients. Using a visual scoring technique, the 156 head–stem pairs were analyzed for the prevalence of fretting and/or corrosion at the trunnion of the stem and the prevalence of metal transfer to the inner taper of the femoral head. Mean patient age was 48 years, and there were 65 men and 13 women. There was no trunnionosis in either group. Prevalence of fretting (81% vs 83%) and corrosion (4% vs 3%) at the trunnion was not significantly different ( P =.518 vs .612, respectively) between the 2 groups. The median fretting scores (1.4±1.1 vs 1.2±1.4 points) and corrosion scores (1.2±0.8 vs 1.3±0.9 points) at the trunnion were not significantly different ( P =.893 vs .781, respectively) between the 2 groups. Prevalence of metal transfer to the inner taper of the femoral head (8% vs 10%) and the median metal transfer scores (1.2±0.9 vs 1.4±1.1 points) were not significantly different ( P =.213 vs .729, respectively) between the 2 groups. [ Orthopedics . 2019; 42(1):e99–e103.]

Because the clinical and radiographic performance of an ultrashort anatomic cementless stem has been investigated in only two randomized controlled studies, well-designed trials should aim for a thorough comparison of the outcomes of ultrashort anatomic cementless and conventional anatomic cementless stems.The purposes of this study were to compare (1) the clinical results, including Harris hip score, thigh pain, and WOMAC index score, (2) radiographic results, (3) bone mineral density; and (4) proportions of patients undergoing revision of a THA using an ultrashort anatomic cementless stem versus a conventional anatomic cementless stem in the same patients who underwent bilateral sequential THAs under the same anesthetic.Two hundred patients (mean age, 53 years; range, 26-54 years) who underwent bilateral sequential THAs received an ultrashort anatomic cementless stem in one hip and a conventional anatomic cementless stem in the contralateral hip. From January 2004 to December 2005, we performed 524 same-day bilateral short and conventional anatomic cementless THAs in 262 patients, of whom 212 (81%) participated in this study. Five patients were lost to followup before 2 years, five were lost between 2 to 10 years, and two were lost between 10 to 13 years, leaving 200 patients. Patients who had end-stage bilateral hip disease and were younger than 55 years were selected for inclusion. The predominant diagnoses were osteonecrosis (118 patients, 59%) and osteoarthritis (44 patients, 22%). One hundred thirty-eight were men and 62 were women. At the time of each followup, the patients were assessed clinically and radiographically. In addition, each patient completed the WOMAC and the University of California Los Angeles (UCLA) activity scores. The minimum followup was 10 years (mean, 11.8 years; range, 10-13 years). Followups were done in person, with all images and followup clinic notes. Based on the power analysis, we estimated a sample size of 178 hips was needed in each group to detect a 3-point difference in the Harris hip score with 80% power.At the latest followup, there were no differences between the two groups regarding the mean Harris hip scores (94 versus 94 points; p = 0.189), mean WOMAC scores (17 versus 16 points; p = 0.191), or mean UCLA activity scores (9 versus 9 points; p = 0.381). Two patients in the ultrashort stem group and one patient in the conventional stem group had severe (9 points) thigh pain, and 30 patients (15%) in the conventional stem group had mild thigh pain (2 or 3 points) after vigorous exercise. Bone mineral density in the ultrashort and conventional stem groups, respectively, was greater in the ultrashort stem group than in the conventional stem group. Bone mineral density in Zone 1 at 12 years was 3.29 versus 1.88 g/cm(2) (p = 0.021), and 2.97 versus 0.91 g/m(2) in Zone 7 (p = 0.001). With the numbers available, there were no differences between the stem designs in terms of the proportion undergoing revision (one hip, 0.5%, in the short-stem group versus one hip, 0.5%, in the conventional group; p = 1.881).At followup into the second decade, ultrashort stems showed no differences from conventional cementless stems in terms of validated outcomes scores or fixation, although less stress shielding was observed. Reduction of stress shielding may reduce the long-term risk of periprosthetic fracture, but this was not shown in our study.Level I, therapeutic study.

Background Several different total knee implants were introduced in an attempt to potentially improve outcomes of total knee arthroplasty in young patients. The object of this study was to compare the clinical outcomes of 5 models of total knee implants. Methods We compared 172 patients who received posterior substituting knee implants with an average 13.2-year follow-up, 182 patients who received high-flex knees with an average 11.8-year follow-up, 190 patients who received mobile-bearing knees with an average 13.9-year follow-up, 170 patients who received gender-specific knees with an average 10.8-year follow-up, and 192 patients who received oxidized zirconium knees with an average 13.5-year follow-up. There were 186 men and 720 women (mean age, 53.3 years; range, 40-60). The mean follow-up was 12.6 years. Results We found similar postoperative Knee Society knee and function scores ( P = .693 and P = .698, respectively), postoperative Western Ontario MacMaster Universities Osteoarthritis Index score ( P = .523), University of California, Los Angeles activity score ( P = .651) and range of knee motion ( P = .417), radiographic results ( P > .05), revision rates ( P = .241), and survivorship ( P = .981) of the implants. Conclusions Range of knee motion, prevalence of polyethylene wear, osteolysis, revision rates, and survivorship of 5 models of total knee arthroplasties were similar. We believe that good designs with a good quality of polyethylene and defined surgical techniques provided good clinical and radiographic outcomes of these 5 models of total knee arthroplasties at this length of follow-up.

We report 400 patients (mean age, 53 years) who received a short stem (17.8 years of follow-up) and 201 patients (mean age 53 years) who received an ultra-short stem (12.3 years of follow-up). At the final follow-up, the mean Harris hip score, WOMAC score and the mean UCLA activity scores were not different between two groups. No patient had thigh pain in either group. Two hips (0.3%) in the short stem group were revised because of early postoperative infection and one hip (0.2%) in the ultra-short stem group was revised for fracture of the proximal femur. Metaphyseal engaging short and ultra-short anatomic cementless stem without diaphyseal fixation provided long-term durable fixation in young and active patients.

Background Our study determined the long-term clinical, radiographic, and computed tomography scanning results of high-flexion mobile-bearing and fixed-bearing total knee arthroplasties (TKAs) in the same younger patients. In addition, the survivorship and complication rates of both groups were evaluated. Methods Bilateral simultaneous sequential TKAs were performed in 164 patients (328 knees). There were 142 women and 22 men with a mean age of 63 ± 9 years (range 41-65), who received a high-flexion mobile-bearing prosthesis in one knee and a high-flexion fixed-bearing prosthesis in the other. The mean follow-up was 16.9 years (range 15-18). Results At the latest follow-up, the mean Knee Society knee scores (94 ± 8 vs 95 ± 9 points, P = .7), Western Ontario and McMaster Universities Osteoarthritis Index (20 ± 11 vs 20 ± 11 points, P = 1.0), range of knee motion (125° ± 10° vs 127° ± 9°, P = .8), and University of California, Los Angeles activity scores (7.8 vs 7.8 points, P = 1.0) were below the level of clinical significance between the 2 groups. Survival rate of high-flexion mobile-bearing TKA was 98.2% and that of high-flexion fixed-bearing TKA was 97% at 16 years. No osteolysis was identified in either group. Conclusion After a minimum duration of follow-up of 13 years, we found no significant difference between these 2 groups with regard to functional outcome, knee motion, prevalence of osteolysis, or survivorship. This study does not clearly direct the surgeon toward either arm of treatment. Longer term follow-up is needed to prove the superiority of one type of implant over the other one.

Our prospective study evaluated the incidence and location of deep vein thrombosis (DVT), the risk factors for PE and the natural history of DVT after TKA in patients who have received only mechanical compression device without having any chemical thromboprophylaxis or therapeutic treatment. We studied 408 consecutive patients (691 knees) who underwent primary TKA; 283 patients had one-stage bilateral TKAs and 125 had unilateral TKAs. Coagulation assays, the full blood count and blood typing tests, and serum chemical profiles were undertaken in all patients on three separate occasions. Molecular genetic testing was performed preoperatively to detect the genetic traits involving DVT. Bilateral simultaneous or unilateral venograms were carried out at 6 or 7 days after operation. Perfusion lung scanning was undertaken before and at 7 or 8 days after operation. In the 691 venograms in 408 patients, only 4 knees (0.6%) were positive for fresh thrombi. In the 4 knees with DVT, thrombi were located in the calf veins. We observed factor V Leiden mutation, antithrombin-III level, and prothrombin promoter G20210A mutation were absent in all patients. We saw no relationship between DVT and coagulation or thrombophilic data. No pulmonary embolism (PE) occurred as shown by negative perfusion lung scan and absence of symptoms. We concluded that the combinations of absent thrombophilic polymorphisms with low clinical prothrombotic risk factors led to low prevalence of DVT and virtually absent PE after TKA in the current series of patients, who had received mechanical compression device only without chemical thromboprophylaxis.

The objective of this study was to ascertain whether combined intravenous (IV) and intra-articular (IA) administration of tranexamic acid (TXA) is beneficial for reducing blood loss and the prevalence of deep venous thrombosis (DVT) in primary simultaneous bilateral total knee arthroplasty compared with IV only administration of TXA. One hundred fifty-four patients received a combined IV and IA injection of TXA in 1 knee and an IV only injection of TXA in the other. Transfusion rates and volumes and the amount of blood loss were recorded at 8 hours, 24 hours, and 48 hours. In addition, the authors ascertained whether the prevalence of DVT was higher in the patients with combined IV and IA administration of TXA than in the patients with IV only administration of TXA. Overall total blood loss was not significantly different (299.6 mL vs 280.1 mL, P =.22) between the 2 groups. The prevalence of DVT was 11% (17 knees) in the combined IV and IA group and 14% (22 knees) in the IV only group. This difference was not significant ( P =.25). Combined IV and IA administration of TXA in bilateral total knee arthroplasty has no additional benefit in reducing total blood loss when compared with IV only administration. The prevalence of DVT was low and not significantly different between the 2 groups. Furthermore, no pulmonary embolism was found in either group. [ Orthopedics . 2018; 41(6):e827–e830.]

Proponents of computer-assisted TKA suggest that better alignment of the TKAs will lead to improved long-term patient functional outcome and survivorship of the implants. However, there is little evidence about whether the improved position and alignment of the knee components obtained using computer navigation improve patient function and the longevity of the TKA.The purpose of this study was to determine whether (1) clinical results; (2) radiographic and CT scan results; and (3) the survival rate of TKA components would be better in patients having computer-assisted TKA than results of patients having TKA without computer-assisted TKA. In addition, we determined whether (4) complication rates would be less in the patients with computer-assisted TKA than those in patients with conventional TKA.We performed a randomized trial between October 2000 and October 2002 in patients undergoing same-day bilateral TKA; in this trial, one knee was operated on using navigation, and the other knee was operated on without navigation. All 296 patients who underwent same-day bilateral TKA during that period were enrolled. Of those, 282 patients (95%) were accounted for at a mean of 15 years (range, 14-16 years). A total of 79% (223 of 282) were women and the mean age of the patients at the time of index arthroplasty was 59 ± 7 years (range, 48-64 years). Knee Society knee score, WOMAC score, and UCLA activity score were obtained preoperatively and at latest followup. Radiographic measurements were performed including femorotibial angle, position of femoral and tibial components, level of joint line, and posterior condylar offset. Aseptic loosening was defined as a complete radiolucent line1 mm in width around any component or migration of any component. Assessors and patients were blind to treatment assignment.The Knee Society knee (92 ± 8 versus 93 ± 7 points; 95% confidence interval [CI], 92-98; p = 0.461) and function scores (80 ± 11 versus 80 ± 11 points; 95% CI, 73-87; p = 1.000), WOMAC score (14 ± 7 versus 15 ± 8 points; 95% CI, 14-18; p = 0.991), range of knee motion (128° ± 9° versus 127° ± 10°; 95% CI, 100-140; p = 0.780), and UCLA patient activity score (6 versus 6 points; 95% CI, 4-8; p = 1.000) were not different between the two groups at 15 years followup. There were no differences in any radiographic parameters of alignment (on radiography or CT scan) between the two groups. The frequency of aseptic loosening was not different between the two groups (p = 0.918). Kaplan-Meier survivorship of the TKA components was 99% in both groups (95% CI, 93-100) at 15 years as the endpoint of revision or aseptic loosening (p = 0.982). Anterior femoral notching was observed in 11 knees (4%) in the computer-assisted TKA group and none in the conventional TKA group (p = 0.046).In this randomized trial, with data presented at a minimum of 14 years of followup, we found no benefit to computer navigation in TKA in terms of pain, function, or survivorship. Unless another study at long-term followup identifies an advantage to survivorship, pain, and function, we do not recommend the widespread use of computer navigation in TKA because of its risks (in this series, we observed femoral notching; others have observed pin site fractures) and attendant costs.Level I, therapeutic study.

Concern regarding osteolysis attributable to polyethylene wear after TKA, particularly in younger patients, has prompted the introduction of highly crosslinked-remelted polyethylene (HXLPE) for TKAs. However, few in vivo comparative results of TKAs using HXLPE and less-crosslinked polyethylene inserts in the same patients are available, regarding fracture or failure of the locking mechanism of tibial polyethylene inserts or of osteolysis in patients younger than 60 years.We wanted to determine whether (1) survivorship free from aseptic loosening in knees with HXLPE inserts was different from survivorship in knees with less-crosslinked polyethylene inserts, (2) the prevalence of fracture or failure of the locking mechanism of the tibial polyethylene insert was greater in knees with HXLPE than in those with less-crosslinked polyethylene, and (3) the proportion of patients who had osteolysis develop was greater with HXLPE than with less-crosslinked polyethylene inserts.One hundred seventy-one patients with a mean age of 58 ± 8 years (range, 35-59 years) received posterior cruciate-retaining prostheses with a less-crosslinked polyethylene tibial insert in one knee and a HXLPE tibial insert in the contralateral knee. From January 2007 to January 2010, we performed 366 same-day bilateral simultaneous sequential posterior cruciate-retaining TKAs in 183 patients, of whom 171 (93%) participated in this study. All patients during this study period underwent posterior cruciate-retaining TKAs regardless of deformity of the knees and we did not perform posterior-stabilized TKAs during the same period. Patients who had bilateral end-stage osteoarthritis and were younger than 60 years were selected for inclusion. Six patients (4%) were lost to followup before 5 years. Twenty-six patients were males and 145 were females. The mean duration of followup was 6 years (range, 5-8 years). At each followup, patients were assessed for loosening of the components, fracture or failure of the locking mechanism of the polyethylene inserts, or osteolysis.The survival rate of the knee prosthesis at a mean of 5.8 years after surgery was 100% (95% CI, 0.95-1.00) in both groups for the endpoint aseptic loosening and 99.4% (95% CI, 0.95-1.00) in both groups for the endpoint revision. No knee in either group had fracture or failure of the locking mechanism of the tibial polyethylene insert, and none had osteolysis.With the numbers available, we found no clinically important differences between HXLPE and less-crosslinked polyethylene inserts in posterior cruciate-retaining TKAs. Given that HXLPE is newer, as-yet unproven, and more expensive than the proven technology (less-crosslinked polyethylene), we suggest not adopting HXLPE for clinical use until it shows superiority.Level I, therapeutic study.

The purpose of this study was to determine long-term clinical and radiographic results. One hundred and ninety-four patients (228 knees) underwent revision TKA with use of a constrained condylar knee prosthesis. The mean duration of follow-up was 14.6 years (range, 11 to 16 years). The mean pre-revision Knee Society knee scores (43.5 points) and function scores (47.0 points), and Western Ontario and McMaster Universities Osteoarthritis index scores (88 points) were improved significantly (P=0.002) to 85.6, 68.5, and 25 points, respectively, at 14.6 years follow-up. Eighteen knees (8%) had re-revision. Four knees were re-revised for infection. Kaplan-Meier survivorship analysis revealed that the 16-year rate of survival of the components was 94.7% as the end point of loosening and 92% as the end point of revision.

The purpose of this study was: (1) to determine the prevalence of deep vein thrombosis (DVT) after the use of a mechanical compression device only, without pharmacological thromboprophylaxis; (2) to investigate the factors associated with DVT; and (3) to investigate the natural course of DVT and PE. We reviewed consecutive series of 874 patients (1434 knees) who received treatment with a mechanical compression device only for prevention of DVT after primary TKA. The prevalence of DVT was 6.6% (94 of 1434 knees). Proximal thrombi were found in 6 of 1434 knees (0.4%). No patient had PE on perfusion lung scans. Further sonograms and venograms for the patients with thrombi at 6 months after the operation revealed that all thrombi were resolved.

Background Numerous studies have investigated the clinical and radiographic results of revision THAs with use of cementless stems and cortical strut allografts. However, to our knowledge, no long-term followup studies have evaluated patients undergoing revision THA with use of cortical strut allografts where the allografts provided the primary stability for extensively coated femoral stems in the presence of extensive femoral diaphyseal bone defects.

Inconsistent results have been reported for posterior-stabilized fixed-bearing and rotating-platform total knee prostheses. The authors sought to determine whether the design changes of these prostheses had led to their achieving their intended objectives at minimum 10-year follow-up. Furthermore, the authors sought to delineate the specific features of these knee prostheses to which good outcomes are attributed. One hundred patients (mean age, 66.2 years) were included in this study. Mean follow-up was 10.4 years (range, 10–11 years). The patients were assessed clinically and radiographically with the Knee Society clinical rating system. In addition, the Western Ontario and McMaster Universities Osteoarthritis Index questionnaire was used and the University of California at Los Angeles activity scores were determined preoperatively and at each follow-up visit. The mean Knee Society knee score was 90 points (range, 70–100 points) in the fixed-bearing group and 92 points (range, 75–100 points) in the rotating-platform group at final follow-up. Mean Western Ontario and McMaster Universities Osteoarthritis Index score was 16 points (range, 5–46 points) in the fixed-bearing group and 16 points (range, 6–49 points) in the rotating-platform group. Mean University of California at Los Angeles activity score was 6.5 points (range, 4–10 points) at final follow-up in both groups. No knee had aseptic loosening of the components, and neither group had osteolysis. The predicted implant survival at 10.4 years was 99% as the endpoint of any reoperation in both groups. The findings of this study suggest that cemented posterior-stabilized fixed-bearing and rotating-platform prostheses have favorable clinical and radiographic results. [ Orthopedics. 2018; 41(2):88–94.]

The aim of this study was to determine how ultra-short anatomic cementless vs cemented femoral stems affect the survival of primary total hip arthroplasties in octogenarians. Specifically, the authors investigated whether ultra-short anatomic cementless and cemented femoral components would have similar (1) functional results, (2) radiographic results, (3) revision and survival rates, and (4) complication rates in octogenarians. The authors evaluated 93 consecutive octogenarians (98 hips) in the ultra-short stem group (mean age, 86.5±5.3 years) and 78 consecutive octogenarians (92 hips) in the cemented stem group (mean age, 85.7±5.8 years). The average follow-up was 8.1 years (range, 5–12 years) in the ultra-short anatomic cementless stem group and 7.8 years (range, 5–11 years) in the cemented stem group. Mean preoperative (39 vs 37 points) and postoperative (81 vs 83 points) Harris hip scores were similar in the 2 groups ( P =.131 and .128, respectively). The incidence of thigh pain was 0% in both groups. At final follow-up, mean Western Ontario and McMaster Universities Osteoarthritis Index scores (18 vs 14 points) and University of California, Los Angeles activity scores (4.3 vs 4.5 points) were similar in the 2 groups. The revision rate was 3% (3 hips) in the ultra-short stem group and 3% (3 hips) in the cemented stem group. Survivorship of the femoral stem was 97.3% at 8.1 years in the ultra-short stem group and 97.9% at 7.8 years in the cemented stem group ( P =.136). Ultra-short anatomic cementless and cemented stems obtained rigid fixation in octogenarians. However, the incidence of undisplaced periprosthetic calcar fracture intraoperatively was significantly higher ( P =.003) in the cemented stem group. [ Orthopedics . 2018; 41(4):e470–e478.]

Background The available comparative studies of computer navigation-assisted and conventional knee arthroplasties have short-term follow-up periods. Therefore, the clinical benefits after long-term follow-up are not clear. The purposes of the current long-term study were to compare clinical outcomes, alignment of the knee components, prevalence of aseptic loosening of the components, implant survival, and complications of total knee arthroplasties performed with and without computer navigation. Methods We prospectively compared the results of 162 consecutive patients (324 knees) with osteoarthritis. These patients had computer-navigated knee arthroplasty in 1 knee and knee arthroplasty without computer navigation in the other. Nine men and 153 women were enrolled in the study. At the time of the index arthroplasty, the mean age of these patients was 68.1 years (range, 49 to 81 years). The mean duration of follow-up was 12.3 years (range, 12 to 13 years). Clinical and radiographic follow-up examinations of the patients were performed at 3 months, 1 year after the operation, and every 2 or 3 years thereafter. Results The Knee Society knee score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and range of knee motion were not significantly different between the groups preoperatively or at 12.3 years of follow-up. Patient satisfaction at the final follow-up was not significantly different between the groups. There were no significant differences between the groups with respect to the position and loosening of the components at 12.3 years of follow-up. The Kaplan-Meier survivorship, with revision or loosening as the end point, was 100% (95% confidence interval [CI], 94% to 100%) at 12.3 years in both groups. The prevalence of anterior femoral notching was higher in the computer-navigated knee arthroplasty group (5%) than in the conventional knee arthroplasty group (0.6%). Conclusions Clinical function, position, and survivorship of the components were similar between the groups. The only effect of navigation was a negative one, anterior femoral notching. However, comparison of bilateral total knee arthroplasties may dampen the differentiation regarding pain outcomes. Further, the findings of this study are specific to a single navigation and total knee system. Level of evidence Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Background There is none, to our knowledge, about comparison of high-flexion fixed-bearing and high-flexion mobile-bearing total knee arthroplasties (TKAs) in the same patients. The purpose of this study was to determine whether clinical results; radiographic and computed tomographic scan results; and the survival rate of a high-flexion mobile-bearing TKA is better than that of a high-flexion fixed-bearing TKA. Methods The present study consisted of 92 patients (184 knees) who underwent same-day bilateral TKA. Of those, 17 were men and 75 were women. The mean age at the time of index arthroplasty was 61.5 ± 8.3 years (range 52-65 years). The mean body mass index was 26.2 ± 3.3 kg/m 2 (range 23-34 kg/m 2 ). The mean follow-up was 11.2 years (range 10-12 years). Results The Knee Society knee scores (93 vs 92 points; P = .531) and function scores (80 vs 80 points; P = 1.000), WOMAC scores (14 vs 15 points; P = .972), and UCLA activity scores (6 vs 6 points; P = 1.000) were not different between the 2 groups at 12 years follow-up. There were no differences in any radiographic and CT scan parameters between the 2 groups. Kaplan-Meier survivorship of the TKA component was 98% (95% confidence interval, 93-100) in the high-flexion fixed-bearing TKA group and 99% (95% confidence interval, 94-100) in the high-flexion mobile-bearing TKA group 12 years after the operation. Conclusion We found no benefit to mobile-bearing TKA in terms of pain, function, radiographic and CT scan results, and survivorship. Longer-term follow-up is necessary to prove the benefit of the high-flexion mobile-bearing TKA over the high-flexion fixed-bearing TKA.

The aim of this study was to determine how an ultra-short anatomic uncemented stem vs a diaphyseal filling five-eighths porous coated uncemented femoral stem (conventional stem) affects the survival of primary total hip arthroplasties in octogenarians. The current study consisted of 52 patients (55 hips) in the ultra-short stem group (mean age, 85.5±5.3 years) and 61 patients (72 hips) in the diaphyseal (conventional) stem group (mean age, 84.1±4.8 years). The predominant diagnosis was osteoarthritis, followed by osteonecrosis of the femoral head, in both groups. Average follow-up was 6.1 years (range, 5–8 years) in the ultra-short stem group and 6.3 years (range, 5–9 years) in the conventional stem group. Pre- (41 vs 39 points) and postoperative (85 vs 86 points) Harris hip scores were similar between groups ( P =.131 and .129, respectively). The incidence of thigh pain was 0% (0 of 52 patients) in the ultra-short stem group and 15% (9 of 61 patients) in the conventional stem group. The revision rate was 1.8% (1 hip) in the ultra-short stem group and 1.4% (1 hip) in the conventional stem group. Survivorship of the femoral stem was 98.2% in the ultra-short stem group at 6.1 years and 98.6% in the conventional stem group at 6.3 years. Ultra-short anatomic and diaphyseal filling uncemented stems obtained osseointegration in all hips. However, the prevalence of thigh pain and periprosthetic fracture were significantly higher in the patients with a conventional stem than in those with an ultra-short stem. [ Orthopedics. 2018; 41(1):28–34.]

The purpose of this study was to investigate the clinical and radiographic results and complication rates after cementless total hip arthroplasty using an ultrashort femoral stem in highly active [University of California, Los Angeles (UCLA) activity level above 8 points] obese and non-obese patients.A total of 108 patients (138 hips) in the obese group [body mass index (BMI) of 30 kg/m(2) or greater] and 125 patients (168 hips) in the nonobese group (BMI of 29 kg/m(2) or less) were enrolled in the study. The mean age was 50.7 ± 11.6 years in the obese group and 48.2 ± 13.0 years in the nonobese group. The mean follow-up was 7.4 years (range six to eight years) and 7.5 years (range six to eight years), respectively.At the final follow-up, there were no significant differences between the highly active obese and nonobese patients with regard to the mean Harris hip score (91 versus 94 points, p = 0.091), the mean Western Ontario and McMaster Universities Osteoarthritis Index (16 versus 11 points, p = 0.135) or the mean UCLA activity scores (8.7 versus 8.8 points, p = 0.400). No hip in either group had thigh pain or a revision or ceramic fracture.The most striking findings in this study were the equivalent results achieved in highly active obese and nonobese patients undergoing primary cementless total hip arthroplasty using an ultrashort metaphyseal-fitting anatomic cementless femoral component.