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Background: We previously reported mid-term results of total hip arthroplasty (THA) using Delta ceramic-on-ceramic (CoC) bearings in 72 patients (86 hips) who were <30 years old. Noise was noted in 8 (9.3%) of the hips, no osteolysis or loosening was detected, and no patient required reoperation. The purpose of this study was to assess clinical and radiographic outcomes, complications, and survivorship at >10 years after THA using Delta CoC bearings in patients who were <30 years old., Methods: Cementless THA with a Delta CoC bearing was performed between March 2008 and January 2012 in 91 hips of 76 patients who were <30 years old. Eighty-five hips in 71 patients (44 men and 27 women) with a mean age of 25.9 years (range, 16 to 29 years) at surgery were followed for a mean of 10.9 years (range, 10 to 13 years)., Results: No ceramic bearings fractured. The incidence of squeaking increased to 5.9% (5 of 85), but the squeaking was not reproducible within individual patients. Periprosthetic osteolysis developed in 3 hips (3 patients): around the stem in 2 and around the metal shell in 1. The stem in 1 hip underwent revision because of a Vancouver type-B2 periprosthetic femoral fracture. One patient with systemic lupus erythematosus underwent irrigation and debridement for periprosthetic joint infection. Survivorship free of reoperation for any reason was 92.4% (95% confidence interval, 82.4% to 100%) at 13 years., Conclusions: The long-term results and survivorship of Delta CoC THA in patients <30 years old were favorable., Level of Evidence: Therapeutic Level II . See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article ( http://links.lww.com/JBJS/H469 )., (Copyright © 2023 by The Journal of Bone and Joint Surgery, Incorporated.)

Background: As no previous study has directly compared the linear wear rate in two types of second-generation annealed highly cross-linked polyethylene, we performed a retrospective study with a minimum of 5-year follow-up to assess primary arthroplasties in the (1) wear rates and (2) incidence of osteolysis of the two types of HXLPE., Hypothesis: There was no significant difference in the linear wear rate and the incidence of osteolysis between the two types of second-generation annealed highly cross-linked polyethylene., Patients and Methods: In this single-center study, we reviewed 257 cases of primary cementless total hip arthroplasties between 2011 and 2015, which were performed with 32mm delta ceramic on second-generation annealed highly cross-linked polyethylene (X3 and E1 were used in 105 and 103 cases, respectively.). The mean wear rate was evaluated using a computer-assisted method, and the incidence of osteolysis was evaluated based on the appearance of a localized area with loss of trabecular bone or cortical erosion adjacent to the implants during the latest follow-up., Results: In total, we evaluated 208 cases, followed postoperatively for over 5 years (mean, 6.1 years, range: 5.0-8.0). There were no significant differences between the two groups with respect to age (list in order of Group X, Group E, p value) (61.2±12.3, 62.7±12.1, p=0.36), sex (ratio of male: 17.1%, 14.6%, p=0.61), body mass index (22.9±3.7, 22.8±4.0, p=0.91), pre- (49.9±14.8, 48.5±13.8, p=0.49) and post-operative (91.3±9.1, 92.7±7.0, p=0.23) Japanese Orthopaedic Association Hip Score, cup size (50.8±3.0, 50.9±2.2, p=0.70), cup inclination (38.7±4.8, 37.6±4.8, p=0.10), and cup anteversion (18.7±6.9, 18.5±7.6, p=0.80). The mean linear wear rates of the X3 and E1 groups were 0.057±0.039 (range: 0-0.16) and 0.054±0.037mm/year (range: 0-0.15), respectively (p=0.61). No osteolysis was found on the final plain radiographs in both groups., Discussion: This study revealed that both types of highly cross-linked polyethylene have excellent linear wear rates and were equally safe to use. However, the difference between the two materials in terms of the long-term wear rate should be further validated., Level of Evidence: III; retrospective case control study., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

Background: Highly cross-linked polyethylene (HXLPE) liners have been developed to address the wear-related problems associated with conventional polyethylene (CPE) such as osteolysis or aseptic loosening in total hip arthroplasty (THA). In this systematic meta-analysis, we compared the long-term efficacy in preventing radiological osteolysis and revision surgery between HXLPE and CPE., Methods: We included 14 studies that compared HXLPE and CPE reporting the incidence of wear-related complications with a minimum follow-up of 10 years. We investigated 5 wear-related complications: osteolysis, excessive wear, linear wear rate, revision surgery due to wear, and progress of osteolysis/aseptic loosening. We conducted a pair-wise meta-analysis to estimate odds ratio (OR) and a proportional meta-analysis to estimate the incidence of each complication., Results: Among 1,175 THAs, 220 osteolysis and 78 wear-related revisions were detected. The use of HXLPE reduced the risk of overall osteolysis (OR 0.30; P = .001), excessive wear (OR 0.10; P < .001), linear wear rate (weighted mean difference 0.09; P < .001), the risk of overall wear-related revisions (OR 0.06; P < .001), and revisions due to aseptic loosening (OR 0.23; P = .015). As per the proportional meta-analysis, the pooled prevalence of osteolysis, excessive wear, and the overall wear-related revision rate were 14%, 8%, and 3% in HXLPE and 25%, 33%, and 20% in CPE, respectively., Conclusion: The current evidence shows that HXLPE dramatically reduced the rate of osteolysis and wear-related revision surgery. However, as polyethylene wear and osteolysis still lead to revision surgery, ongoing clinical and retrieval studies are required to analyze long-term outcomes., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Purpose: The cementless implantation of hip replacement cups may be performed with and without the additional use of acetabular screws. If the surgeon uses screws or not depends on variable factors. In general, the use of screws is intended to increase the primary stability of the cup. Whether screws increase the initial stability of the cup construct, or even reduce it in part, is the subject of considerable debate in the literature. It is also unclear whether the additional screws lead to increased wear or increased periacetabular osteolysis over the long-term course., Methods: Two hundred eleven patients from a previous study with a minimum follow-up of 10.7 years were included. Of these, 68 patients with 82 total hip arthroplasties (THA) were given clinical and radiological follow-up examinations. Of these, 52 had been fitted without screws and 30 with screws. On the basis of radiographs, annual wear and osteolysis were quantified. The clinical results were recorded by means of VAS, HHS, and WOMAC scores., Results: Significantly more periacetabular osteolysis was found if additive acetabular screws had been used. No difference was found in relation to the volumetric wear per year. Likewise, no difference was found with regard to the clinical scores., Conclusions: The use of additive acetabular screws leads to increased osteolysis in the periacetabular bone stock. Insofar as the primary stability of the cementless cup construct allows it, no additional acetabular screws should be used., (© 2021. The Author(s).)

Background: Although highly positive results for wear reduction of highly cross-linked polyethylene (HXLPE) have been reported around the 10-year follow-up, the long-term result related to reoperation and wear-related survival is still an issue. Therefore, this study aimed to compare the follow-up results of a single manufacture's polyethylene liner for >15 years in terms of survival and wear rate., Methods: This retrospective cohort study included 134 primary total hip arthroplasties (THAs) who were followed up for at least 15 years. The mean age at the time of surgery was 50.7 years (conventional polyethylene [CPE] group = 22; HXLPE group = 112). Linear and volumetric wear rates of polyethylene were measured, and the reoperation rate and radiographic osteolysis were evaluated and Kaplan-Meier survival analysis was performed in both groups. Implant-related complications were also examined., Results: HXLPE group showed a significantly lower wear rate in both linear and volumetric wear. None of the hip radiographs showed evidence of loosening or osteolysis in the HXLPE group. The survival rates at 15- to 18-year follow-up were 90.9% and 95.5% in the CPE and HXLPE groups when all-cause reoperation was the endpoint, and 90.9% and 100.0% when the wear-related reoperation was the endpoint, respectively. Implant-related complications were not different between the 2 groups., Conclusions: Wear reduction and osteolysis showed a great advantage in HXLPE after a 15-year follow-up. Although the CPE and HXLPE showed excellent survival, wear and osteolysis were more frequent in the CPE; therefore, the high risk of reoperation in the future should be considered.

Background: This study compared the incidence of osteolysis, aseptic loosening, and revision following use of highly cross-linked polyethylene (HXLPE) or conventional polyethylene (CPE) at medium to long-term (>5 to 15 years) follow-up in primary total hip arthroplasty (THA). Incidences were quantified and compared with regard to age and method of implant fixation., Methods: Using the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines, 12 randomized controlled trials and 18 cohort studies were investigated for evidence-based outcomes following HXPLE and CPE use in 2,539 hips over a 5 to 15-year follow-up., Results: Lower rates of osteolysis, aseptic loosening, and implant revision were reported following use of HXLPE liners. Osteolysis was reduced from 25.4% with CPE to 4.05% with HXLPE in young patients, and from 29.7% to 6.6% in the older patient cohort. Similarities in osteolysis rates were observed when cemented (24.9% for CPE and 6.5% for HXLPE) and uncemented components (32.8% for CPE and 7.1% for HXLPE) were compared. No clear advantage in the type of HXLPE used was observed., Conclusions: Over a follow-up period of up to 15 years, when compared with CPE, use of HXLPE liners reduced the incidence of osteolysis, aseptic loosening, and implant revision, regardless of the fixation method and including in younger and potentially more active patients., Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: The authors indicated that no external funding was received for any aspect of this work. The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJS/G272)., (Copyright © 2021 by The Journal of Bone and Joint Surgery, Incorporated.)

Introduction: Young patients present a challenge for total hip arthroplasty (THA) survivorship. Highly cross-linked polyethylene (HXLPE) liners have decreased the prevalence of osteolysis; however, concerns exist regarding the biologic activity of wear particles. The purpose of this study was to determine the incidence and characteristics of osteolytic lesions in young HXLPE THA patients at an average 16-year follow up and determine the ability to detect osteolysis., Methods: We performed a retrospective study involving 22 patients (26 THA) under age 50 at primary THA receiving HXLPE liners coupled with cobalt-chrome (CoCr) femoral heads. Computed tomography (CT) scans were reviewed for osteolysis. Chi-squared analysis was used for categorical variables and unpaired Kruskal-Wallis rank-sum test for continuous variables. Logistic regression was used to compare wear rates between those patients with and without osteolysis., Results: The mean age at surgery was 38.5 years. The mean time from surgery to CT scan was sixteen years (range 14.25-19.5 years). Nine of the 26 THA showed osteolysis. The mean volume of the lesions was 2.8 cm3. Linear (mean 0.008 mm/y) and volumetric (mean 4.5 mm3/year) wear rates were negligible. One-third of osteolytic lesions were visible on radiographs. Logistic regression failed to demonstrate a correlation between wear rates or UCLA activity score and osteolysis., Conclusion: We observed osteolysis in 35% of HXLPE THA in young patients at mean 16-year follow up despite zero revisions for wear-related problems and clinically insignificant wear rates., Level of Evidence: IV., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: It is often challenging to decide whether to revise only the bearing or femoral acetabular component in the setting of progressive osteolysis without component loosening in revision total hip arthroplasty (THA). In this study, we aimed to (1) compare the survivorship of isolated bearing exchange and single/both component revision for patients with periprosthetic osteolysis without component loosening, and (2) identify potential risk factors associated with failures of isolated bearing exchange., Methods: A total of 228 consecutive cases of revision THA for progressive osteolysis without component loosening was evaluated in 2 groups: (1) 124 component revision and (2) 104 isolated bearing exchange. The primary outcome was survival, with failure defined as repeat revision or reoperation for any reason. Patient risk factors, such as demographics and medical comorbidities, were also analyzed., Results: There was no significant difference in survivorship between the component revision group and the bearing exchange group at 10 years (85% vs 82%; P = .89). There was no progression of osteolysis on radiographs at last follow-up for patients with isolated bearing change. Univariate regression modeling demonstrated that renal disease was associated with failure of isolated bearing exchange after revision THA., Conclusion: This study demonstrated that isolated bearing exchange is associated with similar outcomes compared with component revision for aseptic osteolysis without loosening, demonstrating that isolated bearing exchange is a viable option for selected patients with osteolysis in the setting of well-fixed THA components. This provides clinically useful information for surgeons in the surgical treatment of THA patients with wear and osteolysis without component loosening., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: The aims of the present study are to (1) conduct the longest-to-date follow-up wear analysis of the highly cross-linked polyethylene acetabular liners, (2) assess the incidence of femoral and acetabular osteolysis, and (3) compare the surgical outcomes between standard and elevated-rim acetabular liners in primary total hip arthroplasty (THA)., Methods: In this retrospective cohort study, we evaluated 112 primary THAs performed by a single experienced arthroplasty surgeon at our institution between March 2000 and December 2003. Patients were classified based on the type of acetabular liner used: standard or elevated-rim liner. For evaluation of surgical outcomes, the following data were collected: acetabular cup position (anteversion and inclination), wear rate (linear and volumetric), presence of osteolysis, history of reoperation (all-cause and wear-related), complications (deep joint infection, dislocation, and periprosthetic fracture), and Harris hip score at last follow-up., Results: Linear and volumetric wear rates were 0.028 mm/y (0.000-0.145 mm/y) and 11.641 mm 3 /y (0.000-70.000 mm 3 /y) in the standard group and 0.026 mm/y (0.000-0.094mm/y) and 9.706 mm 3 /y (0.000-33.000 mm 3 /y) in the elevated-rim group, respectively. These rates were not significantly different between groups. One case of osteolysis was confirmed in the standard group, whereas no osteolysis was observed in the elevated-rim group., Conclusion: We suggest that elevated-rim highly cross-linked polyethylene acetabular liners might be a good implant option that can be used safely., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Low polyethylene wear rate and low incidence of osteolysis have been reported after total hip arthroplasty (THA) using first-generation remelted highly cross-linked polyethylene (HXLPE). However, osteolysis has not been evaluated in long-term studies of these patients (15 years or more). The present study assessed computed tomography (CT) images to determine the incidence of osteolysis associated with HXLPE in THA during at least 15 years of follow-up., Methods: We evaluated 105 primary THAs in 84 patients (77 women and 7 men). Mean follow-up was 15.9 years (range, 15-18 years). All THAs used a Longevity HXLPE liner and a 26-mm zirconia femoral head. Areas of osteolysis were identified from CT images using 3D and multiplanar reconstruction views., Results: CT 3D multiplanar reconstruction images at 15-year follow-up showed no obvious osteolysis in the acetabulum or femur of any patient. No patients developed cup loosening or liner breakage., Conclusion: Our study indicates that first-generation remelted HXLPE liners do not increase the risk of osteolysis during 15-year follow-up and suggests that the wear particles from first-generation remelted HXLPE are less biologically active than those generated by conventional polyethylene devices., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Historically, there has been excellent survivorship of total hip arthroplasty with newer implants expected to outperform prior generations. Review of our institutional database identified problems with one particular cross-linked polyethylene liner in mid-term follow-up, which has not been reported in the literature. We report on the technical aspects of this liner, as well as the clinical and radiographic factors associated with early failure of this bearing in our practice., Methods: A retrospective review of our institutional database was performed from January 2009 to June 2019 of patients who presented with significant osteolysis in the setting of prior total hip arthroplasty with a contemporary polyethylene liner. Demographic and radiographic measures were collected for all patients., Results: Twelve patients were identified, with nine undergoing revision surgery. All patients demonstrated radiographic osteolysis at the time of revision surgery. The average time to diagnosis of failure was 55.9 months (range: 12-120 months). Average cup position preoperatively was 44 degrees inclination (range: 36-53 degrees) and 21 degrees anteversion (range: 10-34 degrees). Nine patients underwent revision of the acetabular component, with two also undergoing femoral component revision. The Manufacturer and User Facility Device Experience database revealed 22 reported cases of wear-related failure from 2009 to 2019., Conclusions: Considering that no identifiable risk factors related to patient demographics or implant position were identified, the Exactech Connexion GXL liner may be prone to a high rate of early failure from wear and severe secondary osteolysis. We recommend close surveillance of patients with this bearing surface., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Translational multidisciplinary research is important for the Center for Devices and Radiological Health's efforts for utilizing real-world data (RWD) to enhance predictive evaluation of medical device performance in patient subpopulations. As part of our efforts for developing new RWD-based evidentiary approaches, including in silico discovery of device-related risk predictors and biomarkers, this study aims to characterize the sex/race-related trends in hip replacement outcomes and identify corresponding candidate single nucleotide polymorphisms (SNPs). Adverse outcomes were assessed by deriving RWD from a retrospective analysis of hip replacement hospital discharge data from the National Inpatient Sample (NIS). Candidate SNPs were explored using pre-existing data from the Personalized Medicine Research Project (PMRP). High-Performance Integrated Virtual Environment was used for analyzing and visualizing putative associations between SNPs and adverse outcomes. Ingenuity Pathway Analysis (IPA) was used for exploring plausibility of the sex-related candidate SNPs and characterizing gene networks associated with the variants of interest. The NIS-based epidemiologic evidence showed that periprosthetic osteolysis (PO) was most prevalent among white men. The PMRP-based genetic evidence associated the PO-related male predominance with rs7121 (odds ratio = 4.89; 95% confidence interval = 1.41-17.05) and other candidate SNPs. SNP-based IPA analysis of the expected gene expression alterations and corresponding signaling pathways suggested possible role of sex-related metabolic factors in development of PO, which was substantiated by ad hoc epidemiologic analysis identifying the sex-related differences in metabolic comorbidities in men vs. women with hip replacement-related PO. Thus, our in silico study illustrates RWD-based evidentiary approaches that may facilitate cost/time-efficient discovery of biomarkers for informing use of medical products., (© 2019 The Authors. Clinical and Translational Science published by Wiley Periodicals Inc. on behalf of the American Society of Clinical Pharmacology & Therapeutics. This article has been contributed to by US Government employees and their work is in the public domain in the USA.)

Background: Using data from the Korean Hip Registry, we aimed to investigate mid-term clinical and radiographic outcomes, including the prevalence of periprosthetic joint infection (PJI), osteolysis, and component loosening or dislocation, and to analyze the incidence of bearing-related complications following modern ceramic-on-ceramic (COC) total hip arthroplasty (THA) using a single cementless hip system., Methods: Four hundred eighty-two patients (602 hips) who underwent Forte or Delta COC THAs with a single hip system and had a minimum 5-year follow-up were identified. The sample included 243 (50.4%) women and 239 (49.6%) men with a mean age of 50.6 years (range: 18-83 years). The Forte group comprised 310 hips, and the Delta group comprised 292 hips. The mean follow-up was 6.1 years (range: 5-10.2 years)., Results: Cup orientation did not differ between groups. No hip had a PJI or osteolysis in either group. All acetabular components and all but two femoral components (in the Delta group) were well fixed. Dislocations occurred in six (1.9%) hips in the Forte group and one (0.3%) hip in the Delta group (p = 0.124). A total of nine (1.5%) revisions were performed. The 5-year survival rates for all-cause revisions were 98.4 and 98.6%, respectively. One (0.3%) ceramic head fracture occurred in the Forte group. Sixteen (5%) hips exhibited clicking and 6 (2%) hips had squeaking in the Forte group; 16 (6%) hips exhibited clicking and 5 (2%) hips had squeaking in the Delta group. Multiple regression analysis revealed that noise generation was unassociated with any factor., Conclusions: From the Korean Hip Registry data, THA with modern ceramic bearings showed encouraging results, with lower risks of PJI, osteolysis, and component loosening. In particular, Delta COC THA resulted in no PJI or ceramic fracture and had a reduced dislocation risk. However, associated noise remains a concern.

Background: Patients with surgically treated osteoarthritis of the hip have an increased risk of cardiovascular morbidity and mortality many years after the operation compared with controls. Our hypothesis is that this increased risk after total hip arthroplasty (THA) is mediated by development of periprosthetic osteolysis leading to aseptic loosening of the implant., Methods: We conducted a nation-wide, nested, case-control study consisting of patients receiving a cemented THA due to osteoarthritis between the years 1992 and 2005. Our study population included a total of 14,430 subjects identified in the Swedish hip arthroplasty register and linked to the Swedish National Patient Register. The case group consisted of patients (n = 2,886) who underwent reoperation of the treated hip due to osteolysis or aseptic loosening at any time within five years after the index surgery. Each case was matched with four controls (n = 11,544) who had not undergone reoperation. The main outcomes were cardiovascular events i.e. myocardial infarction, heart failure and cerebral infarction according to ICD-codes and time to the first cardiovascular event during the exposure period. Outcomes were subgrouped into cardiac and cerebral events. We used regression models to calculate the incidence rates and adjusted our results for confounders., Findings: Overall, 5.1% of patients had cardiac events, with slightly more overall cardiovascular events occurring in the control group (8.1% vs. 6.7%, odds ratio 0.8, 95% confidence interval (CI) 0.7 to 1.0). After adjusting for confounders, the case group had an increased relative risk of 1.3 (95% confidence interval (CI) 1.1 to 1.3) for total number of cardiovascular events. Similar effect sizes were observed for time to first event., Interpretation: Patients with osteoarthritis who received THA and subsequently underwent a revision operation due to loosening had a higher relative risk of developing cardiovascular events than controls. Thus there is an association which could be explained by a common inflammatory disease pathway that requires further experimental research., Competing Interests: The authors have declared that no competing interests exist.

Introduction: In revision total hip arthroplasty (THA), the cancellous bone is normally completely removed out of the femoral canal during stem extraction. This situation is comparable to primary THA following the shape-closed concept, with some authors advocating to remove the metaphyseal cancellous bone to enhance press-fit stability ("French paradox"). The aim of this study was to investigate the long-term outcome, regarding survival and radiological results, of a cemented straight stem when used for revision THA and to compare these results to the results of the same stem in primary THA., Materials and Methods: 178 stem revisions performed between 01/1994 and 08/2008 using the Virtec straight stem were included. The cumulative incidence for re-revision was calculated using a competing risk model. Risk factors for re-revision of the stem were analyzed using an absolute risk regression model. Radiographs analyzed for osteolysis, debonding and subsidence had a minimum follow-up of 10 years., Results: The cumulative incidence for re-revision due to aseptic loosening of the stem was 5.5% (95% CI, 2.9-10.2%) at 10 years. Aseptic loosening was associated with younger age, larger defect size and larger stem size. After a minimum 10-year follow-up, osteolysis was seen in 39 of 80 revision THA. Compared to the results in primary THA, the survival in revision THA with the same implant was inferior., Conclusions: Cemented straight stems used for revision THA showed excellent long-term results regarding survivorship and radiological outcome. This stem therefore offers a valuable and cost-effective option in revision THA.

Osteolysis is a long-term complication of total hip arthroplasty (THA). As the projected number of THAs performed annually increases, osteolysis will likely continue to occur. However, because of advancements in prosthesis design, metallurgy, and enhanced bearing surfaces, fewer revision THAs will be linked to osteolysis and aseptic loosening. Despite these improvements, no preventative therapies are currently available for the management of osteolysis other than removing and replacing the source of bearing wear., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Aims: This study evaluated a specific hip resurfacing system to determine the: (1) function and complications, (2) implant survivorship, (3) acetabular bone conservation and joint biomechanics and (4) osteolysis and polyethylene wear., Methods: I performed 234 resurfacing procedures (192 patients) using a two-piece titanium acetabular component with a 4 mm highly cross-linked polyethylene liner and a cementless titanium nitride-coated titanium femoral component. Function was assessed with Harris Hip, WOMAC, SF-12, and UCLA scores. Radiography and CT scans were used to evaluate bone retention, component position, joint biomechanics, and osteolysis. Retrieved polyethylene liners were analyzed for wear., Results: Median follow-up was 8 years and patients averaged 48 years of age at surgery. The mean Harris Hip Score was 96 and all scores improved significantly. Kaplan-Meier survivorship was 97%. The mean medial acetabular thickness was 9 mm postoperatively versus 14 mm preoperatively ( p = 0.019). Femoral bone conservation (head:neck ratio) was 1.36 postoperatively versus 1.42 preoperatively ( p = 0.02). There was no polyethylene wear through or osteolysis. Eight polyethylene retrievals had a mean wear of 0.05 mm/yr., Conclusions: Resurfacing with a highly cross-linked polyethylene acetabular component and a titanium nitride-coated titanium cementless femoral component is a reliable and bone-conserving procedure at mid-term.

In a prospective multicenter trial on highly cross-linked polyethylene inserts in patients undergoing total hip arthroplasty, 118 patients consented to 10-year follow-up. Medium-term follow-up results showed low wear at 5 and 7 years after surgery. The current study focuses on long-term data at 10 years. Patients were followed up by either phone or office visit to collect long-term clinical data including Harris hip score and adverse events. There were 2 deaths and 2 revisions, 1 at 6.5 years for pelvic cyst and severe pain and another at 8.0 years for recurrent dislocation. For wear analysis, suitable radiographic images for 48 patients (52 hips) at minimum 10-year follow-up were available. Mean age of the cohort was 62.5 years (62% female). Femoral head penetration was measured using Martell's method from the radiographic images between the 6-week and the subsequent follow-ups. Polyethylene wear rate was calculated from the penetration data. Descriptive statistics were performed. There was no evidence of significant oxidation or locking mechanism failure. Mean Harris hip score of the group was 94.3. No osteolysis was noted by an independent radiographic reviewer. The slope of the bestfit regression line to the femoral head penetration data, which represents the overall linear wear rate of the polyethylene, was 0.014 mm/y. The wear rate was significantly below the 0.100 mm/y critical threshold for development of osteolysis. Volumetric wear rate was calculated to be 11.6 mm 3 /y. The second-generation highly cross-linked polyethylene acetabular inserts had low wear in the long term (10.3 years) with no incidence of osteolysis. [Orthopedics. 2018; 41(4):e529-e533.]., (Copyright 2018, SLACK Incorporated.)

The Mayo metaphysical conservative femoral stem (Zimmer, Warsaw, Indiana) is a wedge-shaped implant designed to transfer loads proximally, reduce femoral destruction, and enable the preservation of bone stock in the proximal femur. Thus, it is a potentially preferred prosthesis for active, non-elderly patients who may require additional future surgeries. This retrospective case study analyzed the outcomes of consecutive patients who underwent total hip replacements with this stem between May 2001 and February 2013. All patients underwent clinical assessment, radiological evaluation for the presence and development of radiolucent lines, and functional assessment (numerical analog scale, Harris hip score, and Short Form-12 questionnaire). Ninety-five hips (79 patients) were available for analysis. The patients' mean age was 43 years (range, 18-64 years), and the mean follow-up was 97 months (range, 26.9-166 months). The postoperative clinical assessments and functional assessments revealed significant improvements. Sixteen patients (20.3%) had 18 orthopedic complications, the most common of which were an intraoperative femoral fracture and implant dislocation requiring revision surgeries in 10 hips (10.5%). Radiological analysis revealed evidence of femoral remodeling in 64 (67.4%) implants, spot welds (neocortex) in 35 (36.8%), and osteolysis in 3 (3.2%). These results suggest that the conservative hip femoral implant has an unacceptable complication rate for non-elderly patients. [Orthopedics. 2018; 41(4):e516-e522.]., (Copyright 2018, SLACK Incorporated.)

Background: Data on the association between stem type and metal-on-metal (MoM) total hip arthroplasty (THA) performance are limited. The aim of this study is to investigate the effect of stem type on the prevalence of osteolysis and radiolucency, blood metal ion levels, and functional outcomes in patients with Articular Surface Replacement THA (ASR XL), a type of MoM THA., Methods: We analyzed 539 unilateral MoM THAs coupled with Summit (48%), Corail (35%), or S-ROM (17%) hip stems at a mean follow-up of 6.4 years. Fifty-four percent of the patients were male, and the mean age was 60 years. We studied radiographs, patient-reported outcome measures, and ion levels., Results: Patients with S-ROM hip stems were 3.8 times more likely to have osteolysis (P = .003) and 7.6 times more likely to have radiolucency (P < .001) than those treated with Summit hip stems. In addition, patients treated with S-ROM hip stems scored worse than those with Summit hip stems in 4 of the 5 patient-reported outcome measures: Harris Hip Score, Visual Analog Scale pain, University of California at Los Angeles activity, and EQ-5D index. All these differences were statistically significant and ranged from 5% to 10%, which is clinically significant., Conclusion: Patients with S-ROM hip stems had inferior functional and radiographic results compared to patients with Summit hip stems. Retrieval studies on large diameter head MoM THA and close follow-up of these patients with hip stems are needed to understand the mechanism causing the differences in outcomes between these stem types., (Copyright © 2017. Published by Elsevier Inc.)

Introduction: Total hip arthroplasty (THA) with uncemented implants has been a relatively common procedure in Finland during the recent decades. The most common brand of uncemented implants was chosen for further analysis to study the survivorship of this uncemented cup design in comparison to cemented references., Patients, Materials and Methods: Since 1980, The Finnish Arthroplasty Register has collected information on THAs on a national level. This study was based on information of THAs recorded in the Finnish Arthroplasty Register from 1985 to 2013. If patient had undergone bilateral THA, only the first one was included. Altogether, 49,289 THAs were included., Results: The overall 10-year implant survivorship of uncemented implants was 84.3% (95% CI 83.5-85.0%) and of cemented implants 90.6% (90.2-90.0%). The 10-year survival of the contemporary uncemented implants was 90.8% (94.0-95.5%) and 88.5% (84.2-91.7%). The most recently introduced uncemented cup designs had good survivorship rates at 5 years; 10-year survival data are not yet available., Conclusions: We found that modern uncemented cup designs may provide good long-term survivorship rates comparable with the gold standard of cemented cups. However, polyethylene wear, liner problems and periosthetic osteolysis may still occur, also with modern uncemented acetabular components.

Background: The purpose of this retrospective study was to determine the clinical and radiographic results, prevalence of polyethylene wear and osteolysis, and fracture of alumina delta ceramic femoral head or highly crosslinked, remelted polyethylene (HXLPE) liner associated with the use of alumina delta ceramic femoral head-on-HXLPE bearing in cementless total hip arthroplasty in patients younger than 50 years., Methods: We reviewed the cases of 119 patients (130 hips) who underwent a cementless total hip arthroplasty using alumina delta ceramic-on-HXLPE bearing when they were 50 years or younger at the time of surgery. The most common diagnoses were osteonecrosis (51%) and osteoarthritis secondary to developmental dysplastic hip (39%). Osteolysis and polyethylene wear rates were evaluated with use of radiography and computed tomography. In addition, prevalence of fracture of alumina delta ceramic head and polyethylene line was documented. The mean follow-up was 8.3 years (range, 7-9 years)., Results: The mean Harris hip score, Western Ontario and McMaster Universities Osteoarthritis Index score, University of California, Los Angeles activity score were 94 points, 14 points, and 8.1 points, respectively, at the final follow-up. No patient had thigh pain. All acetabular components and all but one femoral components were well fixed. The mean annual penetration rate of femoral head was 0.022 ± 0.003 mm/year. No hip had osteolysis or ceramic head or HXLPE liner fracture., Conclusion: Our average 8.3-year results with the use of alumina delta ceramic-on-HXLPE bearing in the patients younger than 50 years suggest that cementless acetabular and femoral components provide a high survival rate without evidence of osteolysis or ceramic head or AXLPE liner fracture., (Copyright © 2016. Published by Elsevier Inc.)

Introduction: Serum metal ions are part of the regular follow-up routine of patients with metal-on-metal total hip arthroplasties (MoM-THA). Increased cobalt levels have been suggested to indicate implant failure and corrosion., Questions: (1) Is there a correlation between the size of the osteolysis measured on a CT scan and metal ion levels? (2) Can metal ion levels predict the presence of osteolysis in MoM-THA? (3) Are cobalt and chromium serum levels or the cobalt-chromium-ratio diagnostic for osteolysis?, Materials and Methods: CT scans of patients (n = 75) with a unilateral MoM-THA (Birmingham Hip System, Smith & Nephew, TN, USA) implanted by a single surgeon were reviewed to determine the presence of osteolysis. Statistical analysis was performed to detect its association with metal ion levels at the time of the imaging exam., Results: The incidence of osteolysis was the same in men and women (35.6 vs 35.7 %). The cobalt-chromium-ratio correlates with the size of the osteolysis on the CT scan and the femoral component size in the overall study population (p = 0.050, p = 0.001) and in men (p = 0.002, p = 0.001) but not in women (p = 0.312, p = 0.344). The AUC for the cobalt-chromium-ratio to detect osteolysis was 0.613 (p = 0.112) for the overall population, 0.710 for men (p = 0.021) and 0.453 (p = 0.684) for women. The data suggest that a cut off level of 1.71 for the cobalt-chromium-ratio has a sensitivity of 62.5 % and specificity of 72.4 % to identify male patients with osteolysis., Conclusions: The disproportional increase of cobalt over chromium, especially in male patients with large component sizes can not be explained by wear alone and suggests that other processes (corrosion) might contribute to metal ion levels and might be more pronounced in patients with larger component sizes.

Background: The results of third-generation of alumina-on-alumina ceramic bearing in a large number of patient cohorts are limited. The purpose of this study was to determine clinical and radiologic outcome, prevalence of osteolysis detected with radiographs and computerized tomographic scan, and survivorship of a cementless total hip arthroplasty using a third-generation of alumina-on-alumina ceramic bearing in a large number of active patients aged younger than 65 years., Methods: We reviewed the cases of 871 patients (1131 hips) who underwent a cementless total hip arthroplasty when they were aged 65 years or younger at the time of surgery. The most common diagnoses were osteonecrosis (53%) and osteoarthritis (20%). Harris hip score, Western Ontario and McMaster Universities Osteoarthritis Index, and University of California, Los Angeles activity scores were recorded. Radiographic and computerized tomographic evaluations were used to evaluate implant fixation and osteolysis. The mean follow-up interval was 18.8 years (range, 15-20 years)., Results: At the time of final follow-up, the mean Harris hip score, Western Ontario and McMaster Universities Osteoarthritis Index score, and University of California, Los Angeles activity score were 90 points, 15 points, and 8 points, respectively. All the femoral stem and acetabular components were well-fixed at the time of final follow-up. No hip had aseptic loosening or osteolysis or fracture of ceramic material at the time of the final follow-up., Conclusion: The current results with the use of the third-generation of alumina-on-alumina ceramic bearings in young patients suggest that cementless acetabular and femoral components provide outstanding long-term fixation and provide a high rate of survivorship without evidence of osteolysis., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: There are limited studies to evaluate long-term clinical and radiographic outcomes of alumina delta ceramic-on-ceramic bearings in cementless total hip arthroplasty (THA). The purpose of this study was to evaluate the clinical and radiographic results, prevalence of osteolysis, squeaking, and fracture of ceramic material associated with the use of the alumina delta ceramic-on-alumina delta ceramic bearing in cementless THA in patients aged <50 years., Methods: We reviewed the cases of 277 patients (334 hips) who underwent a cementless THA using alumina delta ceramic-on-alumina delta ceramic when they were 50 years or younger at the time of surgery. Demographic data; Harris Hip Score; Western Ontario McMaster Universities Osteoarthritis Index; and University of California, Los Angeles activity score were recorded. Radiographic and computerized tomographic evaluations were used to evaluate implant fixation and osteolysis. Squeaking sound and ceramic fracture were documented. The mean follow-up was 13.1 years (range, 10-14)., Results: The mean postoperative Harris Hip Score, Western Ontario and McMaster Universities Osteoarthritis Index score, University of California, Los Angeles activity score were 93 points, 15 points, and 8.6 points, respectively. Two patients had thigh pain (grade 7 points). All acetabular components and all but 2 femoral components were well fixed. Thirty-three hips (10%) exhibited clicking sound, and 2 hips (0.6%) exhibited squeaking sound. No hip had osteolysis or ceramic head or liner fracture., Conclusion: Our minimum 10-year follow-up results with the use of alumina delta ceramic-on-alumina delta ceramic bearings in patients aged <50 years suggest that cementless THA provides a high rate of survivorship without evidence of osteolysis or fracture of ceramic material., (Copyright © 2016. Published by Elsevier Inc.)

Background: Hip resurfacing is an option to consider when treating younger, more active patients. Advantages over total hip arthroplasty include a more normal gait and a lower incidence of thigh pain., Methods: In this prospective study, 190 hip resurfacing procedures (164 participants) were performed using a cobalt-chromium femoral component and a cementless acetabular cup with a 3.8-mm highly cross-linked polyethylene acetabular liner., Results: The mean follow-up was 8.5 (range, 7-10) years. Two participants were lost to follow-up and 2 died. One participant underwent successful revision surgery for acetabular loosening. Four participants underwent successful revision to a total hip arthroplasty because of femoral neck fracture (2), femoral loosening, or infection. The Kaplan-Meier survivorship was 97%. Acetabular bone conservation was assessed using computed tomography by measuring the medial acetabular wall. The mean thickness was 9 mm. Femoral bone was well preserved with a mean head:neck ratio of 1.37. There were 4 (2%) osteolytic defects up to 0.9 cm(3) on computed tomography and no instances of impending polyethylene wear-through. Seven polyethylene retrievals had a measured wear rate of 0.05 mm/y., Conclusion: Hip resurfacing using a highly cross-linked polyethylene acetabular component is a reliable procedure. Both femoral and acetabular bones are reasonably preserved compared with prior resurfacing methods. The low incidence of osteolysis and the low rate of wear found on retrievals suggest that many years of use in highly active patients is possible., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Highly cross-linked polyethylene was introduced to decrease periprosthetic osteolysis and reoperation, but this has not been conclusively proven., Methods: One surgeon performed 513 consecutive primary total hip arthroplasties (450 patients) using 1 modern, cementless, titanium-mesh acetabular component with screw fixation. This study analyzed the differences in the rate of reoperation and incidence of osteolysis between 133 hips with standard and 112 hips with highly cross-linked polyethylene at minimum 10-year follow-up time., Results: Of the entire cohort of 513 hips, no acetabular component was removed or revised for aseptic loosening. There were significantly more reoperations in the cohort with standard polyethylene (11 of 133, 8%) than highly cross-linked polyethylene (1 of 112, 1%; P = .03). Osteolysis was seen in 24% (32 of 133 hips) with standard polyethylene, compared with 13% (15 of 112 hips) with highly cross-linked polyethylene (P = .02). These differences occurred despite the presence of patients with greater BMI and higher activity in the cohort with highly cross-linked polyethylene., Conclusion: We continue to use this acetabular component with highly cross-linked polyethylene. Longer follow-up is required to determine the progression of osteolysis., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Aims: To investigate the longevity of uncemented fixation of a femoral component in total hip arthroplasty (THA) in patients with Dorr type C proximal femoral morphology., Patients and Methods: A total of 350 consecutive uncemented THA in 320 patients were performed between 1983 and 1987, by a single surgeon using the Taperloc femoral component. The 63 patients (68 hips) with Dorr type C proximal femoral morphology were the focus of this review. The mean age of the patients was 69 years (24 to 88) and mean follow-up was 16.6 years (ten to 29). Survival analysis included eight patients (eight hips) who died without undergoing revision surgery prior to obtaining ten years follow-up. All 55 surviving patients (60 hips) were available for clinical assessment and radiographic review. As a comparator group, the survival and implant fixation in the remaining 282 THAs (257 patients) with Dorr type A and B morphology were evaluated. The mean age of these patients was 52 years (20 to 82)., Results: In the Dorr C patient group the mean Harris hip score improved from 51 points (21 to 69 points) pre-operatively to 89 (74 to 100) at final follow-up. No femoral component was loose by radiological criteria and osteolysis was only identified around two stems (3.3%). There was one revision (1.6%) of a well-fixed femoral component for sepsis at 11 years. The survival of the Taperloc femoral component at 20 years with revision for any reason as the endpoint was 98% (95% confidence interval; 87 to 99). A total of ten (3.5%) of the Dorr A and B patient group of 282 THAs required revision surgery. Only one (0.4%) for aseptic loosening. A total of two hips (1%) were loose by radiographic criteria and osteolysis occurred around 12 hips (4%)., Conclusion: This study demonstrates that excellent fixation can be achieved using the Taperloc stem in patients with Dorr type A and B, and Dorr type C bone., Take Home Message: The Taperloc stem demonstrated equivalent results in Dorr type A and B and Dorr type C bone. Cite this article: Bone Joint J 2016;98-B:595-600., (©2016 The British Editorial Society of Bone & Joint Surgery.)

Objective: The purpose of this article is to determine how often a malignant process presents as a lucency near a hip prosthesis, and to classify the frequency and distribution of differential diagnoses of these lytic lesions, and to determine their disposition., Materials and Methods: Hip and pelvis imaging examinations obtained from January 1998 to June 2008 were text searched (1,164,560 reports) to identify patients with hip prostheses (3508 patients); the records were then searched and individually reviewed to identify periprosthetic lucency (2036 reports; 176 patients). The most likely cause for the lucency, as determined by the interpreting radiologist, was recorded. Malignancy was confirmed in all cases. Malignancy was excluded by biopsy for some patients but by clinical follow-up or at the time of revision, if performed, for most patients. Prevalence rates and 95% CIs were calculated., Results: The overall prevalence of periprosthetic lucency was 5.02%. The prospective diagnoses suggested included loosening or infection (37.5%), degenerative cysts (19.3%), metastases (23.3%), multiple myeloma (14.8%), and metastasis of previously unknown malignancy (3.4%). The prevalence of metastases or multiple myeloma near a hip prosthesis was 1.54%; however, each of these patients had a known prior diagnosis of bone metastases, multiple myeloma, or primary bone malignancy., Conclusion: Among the 2036 examinations with periprosthetic lucency, there were no instances of new malignancy, metastasis, or myeloma. These results suggest that it is statistically unlikely that a lucency near a hip prosthesis represents the first presentation of malignancy or metastases, regardless of how large or aggressive it may appear on imaging.

Background: There have been increasing numbers of publications in recent years on minimally invasive surgery (MIS) for total hip arthroplasty (THA), reporting results with the use of different head sizes, tribologic and functional outcomes. This study presents the results and early complication rates after THA using the direct anterior approach (DAA) in combination with head sizes ≥ 36 mm., Methods: A total of 113 patients with THA were included in the study. The Harris Hip Score (HHS) was determined, a radiographic evaluation was carried out, and complications were recorded. The minimum follow-up period was 2 years (means 35 ± 7 months)., Results: The HHS improved from 43.6 (± 12) to 88.2 (± 14; P < 0.01). One early infection occurred, one periprosthetic fracture, and three cases of aseptic stem loosening. No incorrect positioning of the implants was observed, and there were no dislocations., Conclusion: THA with the minimally invasive DAA in combination with large heads is associated with good to very good functional results in the majority of cases. The complication rates are not increased. The rate of dislocation mainly as an complication of the first two years can be markedly reduced in particular.

Purpose: Cementless acetabular fixation for total hip arthroplasty (THA) is widely used. The question of using screws for a better primary and secondary acetabular fixation has been discussed in the literature in recent years. The aim of this meta-analysis was to compare fixation of acetabular cups with and without screws in total hip arthroplasty., Methods: Electronic databases Embase, PubMed and Cochrane Library were used to search for randomised controlled trials reported through May 2013 of cementless acetabular fixation for THA with and without screws. Two independent reviewers assessed the trials for eligibility and quality. All related data matching our standards were abstracted for meta-analysis by RevMan 5.0. Evaluation criteria included revisions, migration and osteolysis., Results: A total of 1,130 THAs enrolled into five trials were included in this meta-analysis. All studies compared fixation of acetabular cups with and without screws, and our pooled data showed no statistical significance between the two surgical methods in revision, migration and osteolysis., Conclusion: There is no significant difference between cementless acetabular fixation for THA with and without screws in revisions, migration or osteolysis.

Objective: To compare the effectiveness and linear wear rates between high cross-linked polyethylene cup liner and traditional polyethylene cup liner., Methods: A retrospective analysis was made on the clinical data of 61 patients (64 hips) who underwent primary total hip arthroplasty (THA) between January 2005 and March 2007. According to the type of cup liner, 61 patients (64 hips) were divided into 2 groups: high cross-linked polyethylene cup liner was used in 30 cases (31 hips, trial group), and traditional polyethylene cup liner in 31 cases (33 hips, control group). There was no significant difference in gender, age, body weight, etiological factor, and preoperative Harris score between 2 groups (P > 0.05). Complication was observed after operation; Harris score was used to assess hip function; X-ray film analysis was done to observe osteolysis and prosthesis loosening, and to measure cumulative penetration of the femoral head and linear wear rate., Results: All incisions healed by first intention without complication. All patients were followed up. The mean follow-up was 6.3 years (range, 5-7 years) in trial group, and was 6.5 years (range, 4-7 years) in control group. There was no significant difference in Harris score between 2 groups at the 3 months after operation and last follow-up (P > 0.05). Osteolysis was observed in 3 cases (3 hips) of control group, but no osteolysis in trial group. X-ray films showed no aseptic loosening in the patients of 2 groups. The mean cumulative penetration of trial group were significantly lower than those of control group at 1-7 years after operation (P < 0.05). Linear wear rate of trial group [(0.025 +/- 0.002) mm/year] was significantly lower than that of control group [(0.086 +/- 0.005 ) mm/year] (Z=6.804, P=0.000)., Conclusion: High cross-linked polyethylene cup liner has the similar effectiveness as traditional polyethylene cup liner, but it has lower linear wear rate than the traditional polyethylene cup liner.

Background: Dual-mobility (DM) cups were introduced to minimize the risk of THA dislocation. The overall rate of dislocation of DM cups (including both large and small articulations) is controversial and ranges from 0% to 5% in previous studies., Questions/purposes: We therefore recorded (1) the dislocation rate, (2) loosening and osteolysis, and (3) subsequent related revisions with DM cups., Methods: Between 1998 and 2003, 2480 primary THAs with DM cups were undertaken in 2179 patients. The mean age was 69 years (range, 19-94 years). This group underwent specific clinical and radiographic evaluation at a minimum followup of 0.17 years (mean, 7 years; range, 0.17-11 years) to assess dislocation, reoperation, osteolysis, and cup fixation., Results: There were 22 dislocations (0.88%): 15 dislocations of large articulations (0.6%), with two (0.08%) recurring but only one requiring revision (0.04%), and seven intraprosthetic small articulation dislocations (0.28%), all needing revision surgery. At last followup, mean Harris hip score was 91 (range, 60-100); 2439 cups (98%) showed no signs of loosening; and 141 patients (145 hips) had osteolysis (6%). Osteolysis and cup loosening were more frequent in patients younger than 50 years at the time of surgery. The 10-year survivorship considering revision for any reason was 93% (95% CI, 91%-95%)., Conclusions: DM cups had a low dislocation rate in primary THA, with a limited frequency of adverse effects. We recommend DM cups to minimize dislocation in populations at high risk for instability, but they should be avoided in younger, active patients at higher risk for osteolysis.

Purpose: Very few studies have compared alumina-on-alumina ceramic and alumina-on-highly cross-linked polyethylene bearings in the same patient. The purpose of this prospective randomised study was to compare the clinical and radiographic results and the prevalence of osteolysis in cementless total hip arthroplasty using an alumina-on-alumina and alumina-on-highly cross-linked polyethylene bearings in young active patients., Methods: We prospectively compared the results of 100 patients (200 hips) who had undergone a cementless total hip arthroplasty with an alumina-on-alumina ceramic bearing in one hip and an alumina-on-highly cross-linked polyethylene in the other. There were 66 men and 34 women with a mean age of 45.3 years (range, 21-49 years) at the time of surgery. The mean follow-up was 12.4 years (range, 11-13 years). The patients were assessed clinically and radiographically at three months, one year, and annually thereafter., Results: Harris hip, Western Ontario and McMaster Universities Osteoarthritis Index, and University of California, Los Angeles activity scores did not show statistically significant differences between the two groups of bearings preoperatively or at the time of final follow-up. Radiographic findings of the component were not significantly different between the two groups. The mean polyethylene linear penetration was 0.031 ± 0.004 mm per year. No hips in either group displayed osteolysis. The Kaplan-Meier survivorship with revision as the end point at 12.4 years was 100% (95% confidence interval [CI], 94-100%) for the femoral component in both groups and 99% (95%CI, 93-100%) for the acetabular component., Conclusion: The clinical and radiographic results of using an alumina-on-alumina ceramic and alumina-on-highly cross-linked polyethylene bearings were similar.

A total of 219 hips in 192 patients aged between 18 and 65 years were randomised to 28-mm metal-on-metal uncemented total hip replacements (THRs, 107 hips) or hybrid hip resurfacing (HR, 112 hips). At a mean follow-up of eight years (6.6 to 9.3) there was no significant difference between the THR and HR groups regarding rate of revision (4.0% (4 of 99) vs 5.8% (6 of 104), p = 0.569) or re-operation rates without revision (5.1% (5 of 99) vs 2.9% (3 of 104), p = 0.428). In the THR group one recurrent dislocation, two late deep infections and one peri-prosthetic fracture required revision, whereas in the HR group five patients underwent revision for femoral head loosening and one for adverse reaction to metal debris. The mean University of California, Los Angeles activity scores were significantly higher in HR (7.5 (sd 1.7) vs 6.9 (sd 1.7), p = 0.035), but similar mean Western Ontario and McMaster Universities Osteoarthritis Index scores were obtained (5.8 (sd 9.5) in HR vs 5.1 (sd 8.9) in THR, p = 0.615) at the last follow-up. Osteolysis was found in 30 of 81 THR patients (37.4%), mostly in the proximal femur, compared with two of 83 HR patients (2.4%) (p < 0.001). At five years the mean metal ion levels were < 2.5 μg/l for cobalt and chromium in both groups; only titanium was significantly higher in the HR group (p = 0.001). Although revision rates and functional scores were similar in both groups at mid-term, long-term survival analysis is necessary to determine whether one procedure is more advantageous than the other.

Patients with ASR implants (resurfacing and large-diameter (XL) metal-on-metal (MoM) total hip arthroplasty), even if asymptomatic and with a stable prosthesis, may present extremely high blood metal ion levels. We report on a consecutive series of fourteen ASR revisions, focusing on osteolysis and their radiographic correspondence and their correlation with blood metal ion levels. At revision, seven hips revealed severe periacetabular osteolysis which was radiographically undetectable in six and asymptomatic in five. Seven hips with no acetabular osteolysis had significantly lower serum Cr and Co ion concentrations (respectively 25.2, 41.1 μg/l) compared to the seven hips with severe acetabular bone loss (respectively 70.1, 147.0 μg/l). Elevated blood metal ion levels should be considered as a warning of undetectable and ongoing periprosthetic osteolysis in asymptomatic patients with ASR prosthesis., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Radiostereometry (RSA) of the cemented Scientific Hip Prosthesis (SHP) reported excessive migration and predicted high failure rates. In a prospective randomized clinical trial we compared minimum 10 years results of the SHP (n=38) with the Omnifit-stem (n=37). Two-year bone remodelling, compared with dual energy x-ray absorptiometry and assessed in regions of interest A-D based on the 7 Gruen zones, showed better periprosthetic bone preservation around the SHP in all but one regions (P<.05). At 10 years Harris Hip Score was better for the SHP (P=.0001) but Oxford Hip Score was the same (P=.79). There were no revisions in either group, but radiographic loosening was definite in 1 SHP and 1 Omnifit. Based on earlier RSA studies, the rough surface finish of the SHP was expected to cause cement abrasion, osteolysis and inferior survival. However our clinical and remodelling results could not confirm these expectations, suggesting that the link of early migration and mid-term clinical results is not sufficiently clear for the SHP., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: Large (36- and 40-mm) femoral heads with highly crosslinked polyethylene liners were introduced to reduce the risk of dislocation after primary total hip arthroplasty (THA), but it is unclear whether the risk is reduced and whether there is osteolysis or liner fracture., Questions/purposes: We therefore determined (1) the incidence of early and late (> 5 years) dislocation; (2) the rate of femoral and acetabular component loosening and revision; and (3) the rate of liner fracture and pelvic osteolysis., Methods: We retrospectively reviewed 112 patients presumed at high risk for dislocation who had 122 primary THAs: 108 with 36-mm and 14 with 40-mm femoral heads. The risk factors were: age > 75 years (80 hips); proximal femur fracture (18); history of contralateral dislocation (two); history of alcohol abuse (two); large acetabulum > 60 mm (six); and other (14). Patients were evaluated for early (< 1 year) and late (> 5 years) dislocation; rate of reoperation; clinical result with Harris hip score; and standard radiographic analysis for radiolucent lines and osteolysis., Results: The rate of early dislocation was 4% (five of 122 hips), all with a 36-mm head. There were no late dislocations in 74 hips followed for 5 to 10 years, no revision for acetabular or femoral loosening, and no liner fractured. There were no hips with pelvic osteolysis and seven hips with an acetabular radiolucent line., Conclusions: The 36- and 40-mm femoral heads were associated with a low risk of dislocation in high-risk patients undergoing primary THA with no osteolysis or liner fracture., Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of level of evidence.

The best bearing to use in the young active population remains unknown because there are currently no evidence-based data to rely on. This article compares the prevalence of periacetabular osteolysis using computerized tomography in patients with metal-on-metal, ceramic-on-ceramic, and metal-on-cross-linked bearings at a minimum 5-year follow-up., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The purpose of this study was to evaluate the functional and radiographic results of patients younger than 30 years who underwent cementless third-generation ceramic-on-ceramic total hip arthroplasty for osteonecrosis of the femoral head. Forty-one patients (56 hips) with a minimum follow-up of 6 years were included. In all cases, third-generation ceramic-on-ceramic articulation was used. Average Harris Hip Scores improved from 52.9 preoperatively to 98.2, and Western Ontario and McMaster Universities Osteoarthritis Index score, from 95.2 to 25.2. Thirty-nine patients returned to their normal occupations. No aseptic loosening or osteolysis was observed. Total hip arthroplasty performed using third-generation ceramic-on-ceramic bearings for osteonecrosis of femoral head was found to provide satisfactory clinical and radiologic results, especially in active, young patients., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Purpose: Our goal was to assess clinical and radiographic outcomes using a second-generation circumferentially proximally porous-coated titanium alloy stem at a minimum of eight years of follow-up., Methods: Ninety-one hips (80 patients) with Fibre Metal Taper (FMT, Zimmer Inc, Warsaw, IN, USA) femoral stems implanted between May 1998 and April 2002 were followed prospectively and re-evaluated at a minimum of eight years postoperatively. The median patient age was 56 (range 34-78) years, with 40 women and 40 men. Radiographic data and clinical follow-up using Harris Hip Score (HHS) and EuroQol (EQ)-5D outcome measures were evaluated., Results: Mean follow-up was 9.61 (range 8-12.3) years. At the time of the most recent follow-up, the mean HHS was 85.8 (range 46-100) points, mean EQ-5D Weighted Health State Index was 0.76 (range 0.05-1.00), and mean EQ-5D Visual Analogue Score was 80 (range 24-100). All stems were biologically stable, with all hips having osseous ingrowth. One stem was revised due to early periprosthetic fracture with stem subsidence. No hip had diaphyseal osteolysis., Conclusions: To our knowledge, the data presented here represent the longest clinical follow-up of this second-generation cementless, proximally porous-coated femoral stem. The stems were found to perform well clinically and radiographically beyond the first five years previously reported in the literature. Patients had high levels of satisfaction and function, and osseous fixation occurred reliably without evidence of distal osteolysis.

Background: It is unknown whether the long-term survival of uncemented acetabular components in revision total hip arthroplasty varies according to component type. The purpose of this study was to compare the survivorship of historical and current uncemented acetabular components following revision total hip arthroplasty., Methods: The study population included 3236 patients who underwent 3448 revision total hip arthroplasty procedures with an uncemented acetabular component at a large United States medical center between January 1, 1984, and December 31, 2004. Patients were actively followed up at regular intervals to ascertain details of subsequent revision surgical procedures, including cup (metal shell plus liner) and liner revisions. The overall survival and the cause-specific survival of ten different acetabular components were compared with use of Cox proportional-hazards regression models, adjusting for age and sex., Results: A total of 605 repeat revisions, including 386 cup revisions, were performed. The corresponding overall survival rate at fifteen years was 69% (95% confidence interval [CI], 67% to 72%). Compared with titanium wire mesh designs, cup revision for aseptic loosening was significantly more common with beaded designs (hazard ratio [HR], 2.01; 95% CI, 1.44 to 2.80) but less common with trabecular metal designs (HR, 0.25; 95% CI, 0.06 to 1.04). There were no liner revisions for wear and/or osteolysis during a median of 5.2 years of follow-up of 534 total hip arthroplasties with cross-linked polyethylene liners, resulting in a significantly lower risk of wear-related revision with cross-linked polyethylene compared with conventional liners. Femoral head size and use of an elevated liner were not associated with the risk of repeat revision., Conclusions: In the setting of revision total hip arthroplasty, cup survival was worse with beaded acetabular designs compared with titanium wire mesh or highly porous designs. Cross-linked polyethylene liners were associated with a reduced risk of wear-related liner revision.

This is a retrospective review of 46 primary total hip arthroplasties using a first-generation highly cross-linked ultrahigh-molecular-weight polyethylene liner (Crossfire; Stryker, Mahwah, NJ) with an average of 9-year follow-up. The purpose of this study was to measure linear penetration rate of first-generation polyethylene to determine if it maintains its wear resistance and fatigue strength over an extended period compared with conventional polyethylene. The mean (SD) total penetration was 0.339 (0.204) mm, and the mean (SD) penetration rate was 0.037 (0.022) mm/y. Our study demonstrated a 74% reduction in total penetration of highly cross-linked polyethylene when compared with historical controls using conventional polyethylene at an average of 9 years. Our results support the belief that highly cross-linked polyethylene does retain its wear resistance over an extended period., (Copyright © 2012 Elsevier Inc. All rights reserved.)

This study reports minimum 5-year results of 95 hips implanted with a Pinnacle (DePuy, Warsaw, Ind) modular metal-on-metal acetabular prosthesis. Clinical scores such as the Harris Hip and Western Ontario and McMaster Universities Arthritis Index revealed excellent clinical outcomes at mean 6-year follow-up. With the use of large-diameter femoral heads, dislocation was rare, occurring in only 1 hip. Moreover, no acetabular and only 3 femoral osteolytic lesions were detected. Kaplan-Meier survivorship at 7 years after arthroplasty was 97.8% for the total hip arthroplasty construct and 100% for the acetabular shell. No unexplained pain or other complication attributable to wear debris or the metal-on-metal articulation was observed. These findings indicate that total hip arthroplasty with this specific modular metal-on-metal bearing performed well in a high-demand population at midterm follow-up., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Outcomes of ultralarge-diameter femoral heads used in metal-on-metal (MOM) total hip arthroplasty (THA) are relatively unknown. This study reports on early failures of the ASR XL (Depuy, Warsaw, Ind) and assesses whether a correlation with cup positioning exists. A retrospective review of 70 consecutive MOM THAs with ultralarge-diameter femoral head and monoblock acetabular component was conducted. Minimum follow-up was 24 months. Of 70 THAs, 12 (17.1%) required revision within 3 years for pain (7), loosening (3), and squeaking (2). Three additional THAs noted squeaking, 2 noted grinding, and 3 additional hips had persistent pain. In total, 20 (28.6%) of 70 demonstrated implant dysfunction. Acetabular components for all symptomatic hips were in acceptable range of cup abduction and anteversion. The failures noted with this design do not correlate to cup placement. The high rate of implant dysfunction at early follow-up suggests serious concerns with the concept of MOM THA with an ultralarge-diameter femoral head paired with a monoblock acetabular cup., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Fourteen hips in 14 patients (all female; average age, 64 years) with severe bone defects due to developmental dysplasia of the hip or migration of the socket were treated with hydroxyapatite block with impacted morselized bone graft in conjunction with a cemented socket. All patients were followed clinically in a prospective fashion, and radiographs were analyzed retrospectively. One initial patient had 17-year follow-up, whereas the remaining 13 patients had follow-up between 4 and 6.5 years. No acetabular components were revised, including the socket of a 17-year postoperative case that remains rigidly fixed and supported by the graft and hydroxyapatite block with only mild polyethylene wear and minor osteolysis. Osteointegration and good clinical outcome were achieved in all cases by reconstruction with this technique in total hip arthroplasty., (Copyright © 2012 Elsevier Inc. All rights reserved.)

It is unknown if the presence of bilateral well-functioning large-head metal-on-metal (MOM) total hip arthroplasties (THAs) leads to higher serum metal ion concentrations than unilateral MOM THA. Elevated levels (chromium, 17 μg/L; cobalt, 19 μg/L) have been associated with poorly functioning MOM THA with metallosis. Fourteen patients having undergone bilateral and 25 patients having undergone unilateral large-head primary MOM THA were compared. Harris Hip Scores, University of California Los Angeles activity scores, radiographs, serum creatinine, and serum cobalt and chromium levels were obtained. Only cobalt ion levels were significantly higher in the bilateral group than in the unilateral group (1.8 μg/L vs 1.0 μg/L, P = .029). Comparatively, this magnitude is clinically rather low because ion levels did not approach those associated with metallosis in either group. We conclude that although patients with well-functioning bilateral MOM THA may have slightly higher cobalt levels, neither cobalt nor chromium levels approach those seen in poorly functioning MOM THA with metallosis., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Total hip arthroplasty (THA) longevity is the primary concern in young patients. Metal-on-metal articulations were reintroduced to reduce polyethylene particle-induced osteolysis and improve survivorship; to date, based on issued reports, this strategy appears to have been successful. In this study, the authors investigated metal-on-metal articulation survivorship and osteolysis incidence in young patients (19-50 years old at index operations) and retrospectively reviewed cementless metal-on-metal THAs in 70 patients (78 hips) with a mean follow-up of 12.4 years. Metasul articulation was used with the Wagner acetabular component in all. Survivorship with revision for any cause was 98.7% (95% confidence interval, 98%-100%), and survivorship due to the development of osteolysis for any lesion was 97.5% (95% confidence interval, 95%-99%). Mean Harris hip score improved from 51 to 95 points at final follow-up. The findings of this study indicate that outcomes of cementless THA with a metal-on-metal bearing in young patients are satisfactory. However, longer-term studies in larger cohorts are required to determine whether metal-on-metal articulations are really a favorable option in young patients., (Copyright © 2011 Elsevier Inc. All rights reserved.)

The purpose of this prospective study was to evaluate the outcomes and survivorship of a trispiked, sintered bead-coated titanium shell with a polished inner surface, no screw holes, and an improved locking mechanism. A total of 506 total hip arthroplasties with a minimum 5-year follow-up were available for review at a mean of 7 years (range, 5-11 years). Three sockets (0.6%) were revised for reasons other than aseptic loosening, and 14 (2.8%) polyethylene liners were exchanged. There was no difference in revision rate between non-cross-linked and highly cross-linked liners (P = .4). There were no cases of radiographic loosening. Retroacetabular osteolysis was identified in 2%. The overall 5-year and 10-year Kaplan-Meier survivorship was 97.5% and 97.4%, respectively, whereas survivorship of the shell was 99.8%., (Copyright © 2011 Elsevier Inc. All rights reserved.)

The results of a prospective multicenter trial comparing 357 hips randomized to total hip arthroplasty with either ceramic-ceramic or ceramic-polyethylene couplings are presented. No statistically significant difference in clinical outcomes scores between the ceramic-ceramic and ceramic-polyethylene groups was observed at any time interval. The mean linear rate was statistically lower (P < .001) in the ceramic-ceramic group (30.5 μm/year) when compared with the ceramic-polyethylene group (218.2 μm/year). The rates of ceramic implant fracture (2.6%) and audible component-related noise (3.1%) were statistically higher in the ceramic-ceramic group when compared with the ceramic-polyethylene group (P < .05). Lastly, there was no statistically significant difference in the dislocation or revision rate between the groups at the time of last clinical follow-up., (Copyright © 2011 Elsevier Inc. All rights reserved.)