Unexpected early loosening of rectangular straight femoral Zweymüller stems with an alumina-reduced surface after total hip arthroplasty-a prospective, double-blind, randomized controlled trial.

BACKGROUND: Alumina particles from the grit blasting of Ti-alloy stems are suspected to contribute to aseptic loosening. An alumina-reduced stem surface was hypothesized to improve osseointegration and show comparable short-term outcomes to those of a standard stem. METHODS: In this prospective, double-blind, randomized trial, 26 standard (STD) and 27 experimental new technology (NT) stems were implanted. The latter were additionally treated by acid etching and ice blasting to remove alumina particles from the grit-blasting process. Follow-up occurred at 12 and 24 months. Bone mineral density (BMD) around the stem was measured by a dual-energy x-ray absorptiometry device (DEXA). Radiographs were reviewed for alterations. Clinical scoring comprised the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Harris Hip Score (HHS). Survival rates were calculated up to 50 months. RESULTS: Lower mean BMD and more severe cortical hypertrophies were found in the NT group. At 12 months, radiolucent lines were observed mostly in the metaphyseal zone for both groups, with a progression tendency in the NT group at 24 months. At 12 months, pain scores and the WOMAC total and physical activity scores were significantly lower in the NT group, without any differences thereafter. The number of NT stem revisions amounted to 6 (24%) and 11 (41%) at 24 and 50 months, respectively. CONCLUSION: In the NT group, unexpected catastrophic failure rates of 41% caused by early aseptic loosening were noted within 50 months. Compared with the STD stems, NT stems lead to poor clinical and radiographic results. LEVEL OF EVIDENCE: II. TRIAL REGISTRATION: NCT05053048.

Application of Elastic Traction Band Combined with Pain Assessment in Elderly Patients After Hip Replacement.

Objective: This study aims to investigate the use of an elastic traction band in conjunction with pain evaluation in geriatric patients after hip replacement. Methods: Eighty hip arthroplasty cases involving senior patients at our institution were chosen for this study, covering the period from February 2021 to January 2022. They were separated into the control and observation groups using the premise of comparing and contrasting the two groups' shared fundamental characteristics. Traditional nursing care was given to the control group, while the observation group got an elastic stretch traction belt and pain assessment nursing care. The application effect of the two groups was observed. Results: Before surgery, there was no statistically significant difference in the Harris hip function score between the two groups (P > .05). Harris scores for research items in both groups improved 6 months after surgery, compared to scores obtained before surgery (P < .05), and the increase was greater in the observation group than in the control group (P < .05). Self-efficacy for physical activity, coping, and the overall SER scale were all greater in the observation group than in the control group (P < .05). There was no statistically significant difference between the two groups on any measure of material wellbeing (P > .05). Mental and physical health scores were better in the observation group than in the control group (P < .05). Patients' social dimensions were compared to those of two control groups, and the results showed no statistically significant difference in terms of social function aspects (P > .05), although the control group reported much lower levels of enjoyment, learning, and work, the observation group reported significantly greater levels (P < .05). Patient treatment compliance study using a rank sum test revealed that the observation group's postoperative exercise compliance was considerably greater than that of the control group. Observation group members were more compliant than control group members, with an average rank of 30.829 compared to 40.171 for both groups (P < .05). Conclusion: Patients who have had hip arthroplasty may benefit from using an elastic traction belt in conjunction with pain assessment to increase the likelihood that they would participate in rehabilitation exercises, so enhancing their self-efficacy, hip function, and quality of life.

Efficacy and Related Factors of Artificial Femoral Head Replacement for Femoral Intertrochanteric Fracture and Nonunion: A Systematic Review and Meta-Analysis.

Background: An intertrochanteric fracture can cause ischemic necrosis in the femoral head, leading to negative effects. There are many types of implants for this fracture procedure, including metal-on-metal, metal-on-polyethylene, ceramic-on-ceramic, and ceramic-on-polyethylene, that are currently in use. The current modification is a hybrid prosthetic implant with high functional capacity compared with predecessors. This study aims to determine the procedure's efficacy in recovery, function restoration, complications, and cost-effectiveness. Methods: Our study used a total of 200 patients undergoing total hip arthroplasty and 135 patients undergoing semi-hip arthroplasty to determine the effectiveness of total hip arthroplasty and femoral head arthroplasty From May 2022 to May 2023. Using the RAOSOFT sampling technique, 132 and 101 in the observation and control group, respectively, the sample is obtained with a confidence interval of 95%, an error margin of 1%, and response interval confidence of 50%. This is a descriptive type of research that relies on a meta-analysis of the available data from PubMed, scholarly articles, and the Chinese biomedical database to gather the fundamental data needed to conduct the research. Data obtained is analyzed using SSPS and STATA and presented in tables showing a summary of the objective measured value. Result: In this study, the Harris joint score of patients in the total hip arthroplasty group was significantly higher than that of the control group, indicating that total hip arthroplasty can restore femoral head function, but still lacks absolute strength like half hip arthroplasty. Conclusions: Femoral head replacement is a complex procedure, but the efficacy in restoring the function is better. In conclusion, despite slow healing and regeneration, the efficacy of complete artificial femoral head replacement is higher in restoring function for various fractures.

Fix and replace: Simultaneous fracture fixation and hip replacement for acetabular fractures in older patients.

INTRODUCTION: Displaced acetabular fractures in the elderly present significant treatment challenges. The 'fix and replace' concept involves open reduction and internal fixation of the acetabulum, providing bony stability to accept the press-fit of an acetabular cup, with a cemented femoral stem. This allows early mobilisation and the advantages this confers. This study of 57 patients treated with fix and replace describes our technique, outcomes, and survival analysis. METHODS: A retrospective review of 57 'fix and replace' procedures in patients aged over 60 was performed. Data was collected on mechanism, fracture type, demographics, time to surgery, comorbidity index, complications, EQ-5D and Oxford hip scores (OHS). Radiographs were reviewed for fracture healing, implant loosening, cup migration, and heterotopic ossification. RESULTS: 57 patients aged 60 to 95 had fix and replace surgery. The median ASA score was 3. The mean Charlson Index was 4.8. 45 patients had a low-energy fall, 6 had a road traffic accident, 3 fell off a bicycle, and 1 mechanism was unclear. The fracture patterns were anterior column posterior hemitransverse (67%), associated both columns (9%), posterior column (9%), posterior column and posterior wall (9%), and transverse (2%). The mean time to surgery was 8.4 days (0-14). 26 out of 57 (46%) received a blood transfusion. Mean length of stay was 17.6 days (7-86). The mean follow-up was 35.5 months. 4 dislocations were treated with closed reduction, whilst 1 required excision arthroplasty. 2 infections resolved with debridement, antibiotics, and implant retention (DAIR), whilst 1 required a two-stage revision. 1 acetabular component had migrated requiring revision. The median pre-injury OHS was 44 (26-48) compared to 37.3 (28-48) at 1 year. There were no deaths at 30-days, whilst at 1 year 7 patients had died. Kaplan Meier survival analysis showed mean survival was 1984.5 days. Implant survival was 90% at 1 year. CONCLUSION: While fix and replace is conceptually attractive, this medically complex patient group requires considerable support peri­ and post-operatively. Further studies are required to provide clinicians with more information to decide on how best to provide a holistic management strategy for such injuries in this frail patient cohort.

Comparison of short-stem versus conventional stem for hip arthroplasty in patients younger than 60 years: 7-14 years follow-up.

PURPOSE: Short-stem prostheses in hip arthroplasty have emerged as an alternative to conventional stems, especially in younger patients. The purpose of this study was to compare functional and radiological results of a short metaphyseal fitting cementless stem versus a conventional stem implant, in patients younger than 60 years. METHODS: All patients operated from January 2006 to April 2013 were included, obtaining a minimum follow-up of 7 years. Harris Hip Score (HHS) and SF-36 (quality of life) questionnaires were applied and the presence of "thigh pain" was specifically assessed. We also compared complication rate, revision rate and average prosthesis survival. Femoral stress shielding (Gruen scale), stem subsidence, varus-valgus tilt and implant stability (Engh scale) were also compared. RESULTS: A total of 101 short-stem and 74 conventional arthroplasties were included, with an average follow-up of 9.82 (7-14) years. HHS functional score and SF-36 were excellent in both implants and no significant difference between them (p > 0.05) was found. However, "thigh pain" was present in 7 patients with conventional stems and none with short-stems (p < 0.001). The survival rate at 13 years was 99%, for both implants, and no significant differences were found between them (χ2(2) = 0.178; p = 0.673). Conventional stems had stress shielding at the greater trochanter in 72% of the cases and 43% at the calcar, being statistically superior (p < 0.001) to the stress shielding observed in the short stems. CONCLUSION: According to our results, this short-stem seems to allow preservation of bone stock, with decreased stress shielding and also a lower incidence of thigh pain compared to conventional stems. LEVEL OF EVIDENCE: Level III retrospective comparative study.

Third-Generation Ceramic-on-Ceramic Total Hip Arthroplasty in Patients with Osteonecrosis of the Femoral Head: A 10- to 16-year Follow-up Study.

BACKGROUND: Long-term follow-up results of ceramic-on-ceramic (COC) total hip arthroplasty (THA), specifically, in patients with osteonecrosis of the femoral head (ONFH) are unknown. We evaluated (1) clinical results and radiological outcomes, (2) ceramic-related complications: noise and ceramic fracture, (3) osteolysis, and (4) survivorship after alumina COC THA in ONFH patients with longer than 10-year follow-up. METHODS: From May 2003 to June 2009, 325 ONFH patients (403 hips) underwent primary THAs at our department. Among them, 231 patients (293 THAs) were followed for 10 to 16 (mean, 12.9) years. There were 148 men and 83 women, their mean age at the time of THA was 47.2 years, and their mean body index was 24.0 kg/m2. The postoperative CT scans were done in 160 hips. RESULTS: Grinding sensation or squeak was noted in 6.8% (20/293), ceramic head fracture occurred in 2.4% (7/293) and acetabular osteolysis developed in 0.7% (2/293). All 7 ceramic fractures occurred in 28-mm short-neck heads. There was no detectable wear or prosthetic loosening, and the 16-year survivorship was 96.0% (95% confidence interval; 93.8% to 98.2%). The mean Harris hip score was 91.7 (range, 84 to 100) points at the final follow-up. CONCLUSIONS: The 10- to 16-year results of alumina COC THAs were encouraging with an excellent survivorship. However, ceramic fracture and noise still remain matters of concern. We recommend not to use 28-mm short-neck ceramic head to avoid ceramic head fractures. LEVEL OF EVIDENCE: III.

Local infiltration analgesia does not have benefits in fast-track hip arthroplasty programmes: a double-blind, randomised, placebo-controlled, clinical trial.

BACKGROUND: Multimodal analgesia regimes including local infiltration analgesia (LIA) have been successfully applied in fast-track hip arthroplasty programmes. LIA's contribution to the analgesic effect in hip arthroplasty has been questioned. Our study sought to determine the analgesic efficacy of LIA in THA surgery in a fast-track programme. METHODS: Patients diagnosed with hip osteoarthritis scheduled for arthroplasty were randomised to receive LIA (120 ml ropivacaine 0.2% plus epinephrine 0.5 µ/ml) or saline as a part of a multimodal analgesia regime. The surgical team, the nursing staff, and patients were all blinded regarding patient allocation throughout the study. The primary outcome was pain assessed as a continuous variable using the visual analogue scale (VAS) at 4, 8, 24 and 48 hours postoperatively. Secondary outcomes included the amount of analgesic rescue consumption, complications and length of hospital stay. RESULTS: A total of 63 patients were interviewed and agreed to participate in the study. No statistically significant differences were found between groups for pain measurements at 4, 8, 12, 24 and 48 hours after surgery. There were also no differences in rescue medication consumption, complications, or length of stay. CONCLUSIONS: Our results suggest LIA (ropivacaine plus epinephrine, single shot) has no effect in pain management and has not shown benefits for early ambulation in primary THA surgery. Further research is needed to establish the optimal multimodal analgesia regime for THA fast-track programmes. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov (NCT03513276).

Spinal Anesthesia Using Ropivacaine Leads to Earlier Ambulation After Total Hip Arthroplasty.

Spinal anesthesia has grown in popularity for total hip arthroplasty (THA) due to its documented low complications. However, the use of a local anesthetic agent dictates the recovery of neuraxial blockade. Bupivacaine has emerged as the most popular choice, but its relatively long-acting effect limits its use with rapid recovery. Although not well studied, ropivacaine may offer a viable alternative with shorter-acting properties. Primary unilateral THA patients who received either ropivacaine or bupivacaine spinal anesthesia were retrospectively reviewed. These groups were compared for common demographics, such as age, sex, and body mass index. The primary outcomes included postoperative ambulation time and distance, post-anesthesia care unit transition time, and selective complications. Five hundred three patients were included. Of these, 227 received ropivacaine and 276 received bupivacaine. The ropivacaine group showed superior ambulation time and distance, quicker post-anesthesia care unit transition, and equivalent complications compared with the bupivacaine group. Ropivacaine shows a clear advantage over bupivacaine for spinal anesthesia during THA when considering rapid recovery. Its use should be strongly considered, especially in the ambulatory setting. [Orthopedics. 2021;44(3):e343-e346.].

Compliance with antibiotic prophylaxis guidelines in surgery: Results of a targeted audit in a large-scale region-based French hospital network.

INTRODUCTION: While regional monitoring of antibiotic use has decreased since 2011 by 3.2%, in some healthcare facilities a significant increase (+43%) has occurred. The purpose of this study was to assess regional antibiotic prophylaxis (ABP) compliance with national guidelines. MATERIAL AND METHODS: In 2015, 26 healthcare facilities, both public and private, were requested to audit five items: utilization of antibiotic prophylaxis, the antimicrobial agent (the molecule) administered, time between injection and incision, initial dose, number of intraoperative and postoperative additional doses. Seven surgical procedures were selected for assessment: appendicectomy (APP), cataract (CAT), cesarean section (CES), colorectal cancer surgery (CCR), hysterectomy (HYS), total hip arthroplasty (THA) and transurethral resection of the prostate (TURP). A statistical analysis of the 2303 records included was carried out. RESULTS: The general rate of antibiotic prophylaxis compliance was 64%. The antimicrobial agent used and initial dose were in compliance with the guidelines for 93% and 97.4% of cases respectively, and administration of antibiotic prophylaxis was achieved 60minutes before incision in 77.6% of the records included. Regarding gastrointestinal surgery, amoxicillin/clavulanic acid was used in 32% of patients. In 26% of appendectomy files, administration occurred after incision, and one out of two files showed non-complaint perioperative and postoperative consumption. CONCLUSION: Compliance with nationwide ABP guidelines is in need of pronounced improvement, especially with regard to time interval between injection and incision and the molecule prescribed. An action plan based on specific recommendations addressed to each establishment and an updated regionwide ABP protocol are aimed at achieving better and reduced consumption of antimicrobial agents.

Spillover effects of mandatory hip and knee replacement surgery bundles in medicare.

BACKGROUND: Medicare used the Comprehensive Care for Joint Replacement (CJR) Model to mandate that hospitals in certain health care markets accept bundled payments for lower extremity joint replacement surgery. CJR has reduced spending with stable quality as intended among Medicare fee-for-service patients, but benefits could "spill over" to individuals insured through private health plans. Definitive evidence of spillovers remains lacking. OBJECTIVE: To evaluate the association between CJR participation and changes in outcomes among privately insured individuals. DESIGN, SETTING, PARTICIPANTS: We used 2013-2017 Health Care Cost Institute claims for 418,016 privately insured individuals undergoing joint replacement in 75 CJR and 121 Non-CJR markets. Multivariable generalized linear models with hospital and market random effects and time fixed effects were used to analyze the association between CJR participation and changes in outcomes. MAIN OUTCOMES AND MEASURES: Total episode spending, discharge to institutional post-acute care, and quality (e.g., surgical complications, readmissions). RESULTS: Patients in CJR and Non-CJR markets did not differ in total episode spending (difference of -$157, 95% CI -$1043 to $728, p = 0.73) or discharge to institutional post-acute care (difference of -1.1%, 95% CI -3.2%-1.0%, p = 0.31). Similarly, patients in the two groups did not differ in quality or other utilization outcomes. Findings were generally similar in stratified and sensitivity analyses. CONCLUSIONS: There was a lack of evidence of cost or utilization spillovers from CJR to privately insured individuals. There may be limits in the ability of certain value-based payment reforms to drive broad changes in care delivery and patient outcomes.

Incidence of silent venous thromboembolism after total hip arthroplasty: A comparison of rivaroxaban and enoxaparin.

PROPOSE: Total hip arthroplasty (THA) is associated with a significant risk of venous thromboembolism (VTE). Different thromboprophylaxis strategies have been used to prevent VTE. The primary aim of this study was to report the incidence of VTE and compare the efficacy and safety of rivaroxaban to enoxaparin. The secondary outcome was to report the incidence of silent deep venous thrombosis (DVT) using computed tomography venography. METHODS: One hundred sixty patients who underwent THA were enrolled in a prospective study. Patients were randomized into two groups as follows: those who received rivaroxaban 10 mg oral daily (group RXE) and those who received enoxaparin 40 IU/day subcutaneously for 14 days (group ENO). RESULTS: Both groups were matched for age, sex, comorbidities, special habits and preoperative laboratory investigations. The overall incidence of DVT was 5% (n = 8), which included four patients clinically diagnosed as having DVT and four with silent DVT. All the DVT cases occurred in veins below the knee and in the group RXE; none of the cases occurred in group ENO (p = 0.04). The incidence of DVT was significantly higher in patients with high body mass indexes (p < 0.001), older age (p = 0.024) and medical comorbidities (p = 0.14). No mortality, pulmonary embolism, stroke, wound infection or major bleeding occurred in either group. CONCLUSIONS: Among the patients who underwent hip arthroplasty, rivaroxaban prophylaxis was found to be associated with lower efficacy and similar safety outcomes as compared with enoxaparin anticoagulants.

Association Between Uncemented vs Cemented Hemiarthroplasty and Revision Surgery Among Patients With Hip Fracture.

IMPORTANCE: Consensus guidelines and systematic reviews have suggested that cemented fixation is more effective than uncemented fixation in hemiarthroplasty for displaced femoral neck fractures. Given that these recommendations are based on research performed outside the United States, it is uncertain whether these findings also reflect the US experience. OBJECTIVE: To compare the outcomes associated with cemented vs uncemented hemiarthroplasty in a large US integrated health care system. DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort study of 12 491 patients aged 60 years and older who underwent hemiarthroplasty treatment of a hip fracture between 2009 and 2017 at 1 of the 36 hospitals owned by Kaiser Permanente, a large US health maintenance organization. Patients were followed up until membership termination, death, or the study end date of December 31, 2017. EXPOSURES: Hemiarthroplasty (prosthetic replacement of the femoral head) fixation via bony growth into a porous-coated implant (uncemented) or with cement. MAIN OUTCOMES AND MEASURES: The primary outcome measure was aseptic revision, defined as any reoperation performed after the index procedure involving exchange of the existing implant for reasons other than infection. Secondary outcomes were mortality (in-hospital, postdischarge, and overall), 90-day medical complications, 90-day emergency department visits, and 90-day unplanned readmissions. RESULTS: Among 12 491 patients in the study cohort who underwent hemiarthroplasty for hip fracture (median age, 83 years; 8660 women [69.3%]), 6042 (48.4%) had undergone uncemented fixation and 6449 (51.6%) had undergone cemented fixation, and the median length of follow-up was 3.8 years. In the multivariable regression analysis controlling for confounders, uncemented fixation was associated with a significantly higher risk of aseptic revision (cumulative incidence at 1 year after operation, 3.0% vs 1.3%; absolute difference, 1.7% [95% CI, 1.1%-2.2%]; hazard ratio [HR], 1.77 [95% CI, 1.43-2.19]; P < .001). Of the 6 prespecified secondary end points, none showed a statistically significant difference between groups, including in-hospital mortality (1.7% for uncemented fixation vs 2.0% for cemented fixation; HR, 0.94 [95% CI, 0.73-1.21]; P = .61) and overall mortality (cumulative incidence at 1 year after operation: 20.0% for uncemented fixation vs 22.8% for cemented fixation; HR, 0.95 [95% CI, 0.90-1.01]; P = .08). CONCLUSIONS AND RELEVANCE: Among patients with hip fracture treated with hemiarthroplasty in a large US integrated health care system, uncemented fixation, compared with cemented fixation, was associated with a statistically significantly higher risk of aseptic revision. These findings suggest that US surgeons should consider cemented fixation in the hemiarthroplasty treatment of displaced femoral neck fractures in the absence of contraindications.

The role of intra-operative cell salvage in patient blood management for revision hip arthroplasty: a prospective cohort study.

Cell salvage is an important component of blood management in patients undergoing revision hip arthroplasty surgery. However concerns regarding efficacy and patient selection remain. The aims of this study were to describe intra-operative blood loss, cell salvage re-infusion volumes and red blood cell transfusion rates for revision hip procedures and to identify factors associated with the ability to salvage sufficient blood intra-operatively to permit processing and re-infusion. Data were collected from a prospective cohort of 664 consecutive patients undergoing revision hip surgery at a single tertiary centre from 31 March 2015 to 1 April 2018. Indications for revision surgery were aseptic (n = 393 (59%)) fracture (n = 160 (24%)) and infection (n = 111 (17%)). Salvaged blood was processed and re-infused when blood loss exceeded 500 ml. Mean (SD) intra-operative blood loss was 1038 (778) ml across all procedures. Salvaged blood was re-infused in 505 of 664 (76%) patients. Mean (SD) re-infusion volume was 253 (169) ml. In total, 246 of 664 (37%) patients received an allogeneic red blood cell transfusion within 72 h of surgery. Patients undergoing femoral component revision only (OR (95%CI) 0.41 (0.23-0.73)) or acetabular component revision only (0.53 (0.32-0.87)) were less likely to generate sufficient blood salvage volume for re-infusion compared with revision of both components. Compared with aseptic indications, patients undergoing revision surgery for infection (1.87 (1.04-3.36)) or fracture (4.43 (2.30-8.55)) were more likely to generate sufficient blood salvage volume for re-infusion. Our data suggest that cell salvage is efficacious in this population. Cases where the indication is infection or fracture and where both femoral and acetabular components are to be revised should be prioritised.

The effectiveness of preoperative colon cleansing on post-operative surgical site infection after hip hemiarthroplasty.

AIM: This study aimed to evaluate the effectiveness of prophylactic mechanical bowel preparation in elderly patients undergoing hip hemiarthroplasty in a single training institution over a period of 2 years. PATIENTS AND METHODS: The study was conducted in a prospective-randomised manner. All patients, who underwent primary hip hemiarthroplasty for femoral neck fracture in our institution between 20 February 2015 and 29 December 2016, were included. B.T. Enema (sodium dihydrogen phosphate + disodium hydrogen phosphate) 135 ml (Yenisehir Laboratory, Ankara, Turkey) was used for colon cleansing. RESULTS: Ninety-five patients were followed up for at least 1 year after surgery (16.3 ± 4.2 months). Of these, 46 were in the enema group and 49 were in the control group. Demographic and clinical characteristics of patients were similar in both groups (p > 0.05). Infection rates between the two groups were not significantly different (p > 0.05). In addition, ASA, age, sex, presence of diabetes mellitus, duration of surgery, time to surgery, ambulation status and blood count did not have a significant effect on surgical site infections (p > 0.05). However, all infections in the enema group were monobacterial and were successfully treated, whereas two of the four infections in the control group were polymicrobial and could not be successfully treated. CONCLUSION: Although preoperative colon cleansing did not reduce the overall incidence of post-operative infections, our study suggested that it may reduce polymicrobial infections after hip hemiarthroplasty. Polymicrobial infections after hip hemiarthroplasty seem to have worse prognosis. Therefore, the effectiveness of preoperative colon cleansing in remediating such infections must be investigated in a larger number of patients.

Mixed Reality Combined with Three-Dimensional Printing Technology in Total Hip Arthroplasty: An Updated Review with a Preliminary Case Presentation.

Three-dimensional (3D) printing technology, virtual reality, and augmented reality technology have been used to help surgeons to complete complex total hip arthroplasty, while their respective shortcomings limit their further application. With the development of technology, mixed reality (MR) technology has been applied to improve the success rate of complicated hip arthroplasty because of its unique advantages. We presented a case of a 59-year-old man with an intertrochanteric fracture in the left femur, who had received a prior left hip fusion. After admission to our hospital, a left total hip arthroplasty was performed on the patient using a combination of MR technology and 3D printing technology. Before surgery, 3D reconstruction of a certain bony landmark exposed in the surgical area was first performed. Then a veneer part was designed according to the bony landmark and connected to a reference registration landmark outside the body through a connecting rod. After that, the series of parts were made into a holistic reference registration instrument using 3D printing technology, and the patient's data for bone and surrounding tissue, along with digital 3D information of the reference registration instrument, were imported into the head-mounted display (HMD). During the operation, the disinfected reference registration instrument was installed on the selected bony landmark, and then the automatic real-time registration was realized by HMD through recognizing the registration landmark on the reference registration instrument, whereby the patient's virtual bone and other anatomical structures were quickly and accurately superimposed on the real body of the patient. To the best of our knowledge, this is the first report to use MR combined with 3D printing technology in total hip arthroplasty.

Anticoagulation in Revision Total Joint Arthroplasty: A Retrospective Review of 1917 Cases.

Although several studies now support the use of aspirin for venous thromboembolism (VTE) prophylaxis in primary total hip arthroplasty (THA) and total knee arthroplasty (TKA), the optimal chemoprophylactic agent in revision THA and TKA is not clear. The purpose of this study was to determine if the type of chemoprophylaxis has an effect on the VTE rate in patients undergoing revision total joint arthroplasty (TJA). The second aim was to compare differences in rates of wound drainage in primary and revision TJA stratified by the postoperative chemoprophylaxis used. The authors retrospectively reviewed 1917 consecutive patients undergoing primary and revision TJA. Individual records were reviewed for patient demographics, medical comorbidities, type of chemoprophylaxis, VTE risk factors, intraoperative data, and postoperative complications. Outcomes, including VTE rate and wound complications, were compared between types of anticoagulant therapy used postoperatively. Of the 1917 patients, there were 742 (38.7%) primary TKAs, 326 (17%) revision TKAs, 608 (31.7%) primary THAs, and 241 (12.6%) revision THAs. The most common prophylactic agent used was rivaroxaban (40.6%), followed by warfarin (28.5%) and aspirin (27.6%). Type of chemoprophylaxis was not associated with postoperative VTE or wound drainage (P>.05). Although revision surgery was an independent risk factor for wound drainage (odds ratio, 3.201; 95% confidence interval, 1.594-6.426; P=.001), it was not a risk factor for VTE (odds ratio, 1.847; 95% confidence interval, 0.423-8.053; P=.414). Revision arthroplasty alone was not associated with an increased rate of VTE. Aspirin is as effective as other chemoprophylactic agents without the increased risk of bleeding in low-risk patients. [Orthopedics. 2019; 42(6):323-329.].

Short and mid-term outcomes and functional results in metal-on-metal hip resurfacing arthroplasty at 5 years follow-up: the Spanish experience.

BACKGROUND: Hip resurfacing arthroplasty (HRA) and in particular, Birmingham hip resurfacing (BHR), is commonly employed as an alternative to total hip arthroplasty (THA) in young patients, as it allows for preservation of femoral bone stock and resumption of physical activity. The aim of our study was to investigate 5-year survival and functional outcomes of BHR arthroplasty in young Spanish osteoarthritis (OA) patients. METHODS: This is an observational, prospective, cohort study of patients who underwent BHR between June 2005 and December 2009 at a Spanish public hospital with a minimum follow-up of 5 years. All surgeries were performed by a single surgeon (RLM). Survival was analyzed using the Kaplan-Meier method. Functional outcomes and return to work and physical activities were also assessed. RESULTS: Five-year survival rate of the prosthesis was 95.74% (95% CI: 95.77-98.07), and estimated 10-year survival was 92.92% (95% CI: 85.07-96.72). Harris hip score significantly increased from 41.13 to 97.63 (p < 0.001) at 5-year follow-up. Average time for returning to work and sporting activities was 3.89 (SD: 2.39) and 3.47 (SD: 1.18) months respectively. Failure occurred in 14 patients, 8 of whom experienced femoral neck fractures. CONCLUSIONS: Our data support the short and mid-term efficacy of BHR arthroplasty in young OA patients, indicating good implant survival, improvement in patients' functionality and a swift return to work and physical activities after surgery.

Is a modular dual mobility acetabulum a viable option for the young, active total hip arthroplasty patient?

AIMS: Modular dual mobility (DM) prostheses in which a cobalt-chromium liner is inserted into a titanium acetabular shell ( vs a monoblock acetabular component) have the advantage of allowing supplementary screw fixation, but the potential for corrosion between the liner and acetabulum has raised concerns. While DM prostheses have shown improved stability in patients deemed 'high-risk' for dislocation undergoing total hip arthroplasty (THA), their performance in young, active patients has not been reported. This study's purpose was to assess clinical outcomes, metal ion levels, and periprosthetic femoral bone mineral density (BMD) in young, active patients receiving a modular DM acetabulum and recently introduced titanium, proximally coated, tapered femoral stem design. PATIENTS AND METHODS: This was a prospective study of patients between 18 and 65 years of age, with a body mass index (BMI) < 35 kg/m2 and University of California at Los Angeles (UCLA) activity score > 6, who received a modular cobalt-chromium acetabular liner, highly crosslinked polyethylene mobile bearing, and cementless titanium femoral stem for their primary THA. Patients with a history of renal disease and metal hardware elsewhere in the body were excluded. A total of 43 patients (30 male, 13 female; mean age 52.6 years (sd 6.5)) were enrolled. All patients had a minimum of two years' clinical follow-up. Patient-reported outcome measures, whole blood metal ion levels (ug/l), and periprosthetic femoral BMD were measured at baseline, as well as at one and two years postoperatively. Power analysis indicated 40 patients necessary to demonstrate a five-fold increase in cobalt levels from baseline (alpha = 0.05, beta = 0.80). A mixed model with repeated measures was used for statistical analysis. RESULTS: Mean Harris Hip Scores improved from 54.1 (sd 20.5) to 91.2 (sd 10.8) at two years postoperatively (p < 0.001). All patients had radiologically well-fixed components, no patients experienced any instability, and no patients required any further intervention. Mean cobalt levels increased from 0.065 ug/l (sd 0.03) preoperatively to 0.30 ug/l (sd 0.51) at one year postoperatively (p = 0.01) but decreased at two years postoperatively to 0.16 ug/l (sd 0.23; p = 0.2). Four patients (9.3%) had a cobalt level outside the reference range (0.03 ug/l to 0.29 ug/l) at two years postoperatively, with values from 0.32 ug/l to 0.94 ug/l. The mean femoral BMD ratio was maintained in Gruen zones 2 to 7 at both one and two years postoperatively using this stem design. At two years postoperatively, mean BMD in the medial calcar was 101.5% of the baseline value. CONCLUSION: Use of a modular DM prosthesis and cementless, tapered femoral stem has shown encouraging results in young, active patients undergoing primary THA. Elevation in mean cobalt levels and the presence of four patients outside the reference range at two years postoperatively demonstrates the necessity of continued surveillance in this cohort. Cite this article: Bone Joint J 2019;101-B:365-371.

Impact of stem taper damage on the fracture strength of ceramic heads with adapter sleeves.

BACKGROUND: Using a new ceramic head with a titanium adapter sleeve offers the possibility of maintaining a well fixed stem when conducting cup revision of a total hip arthroplasty. The aim of this study is to test the impact of stem taper damage on the fracture strength of sleeved ceramic heads. METHODS: Pristine zirconia-toughened alumina heads with titanium adapter sleeves (BIOLOX®OPTION System) were tested on damaged Ti-4Al-6V stem tapers in accordance with ISO7206-10. Four distinctive damage types classified as intolerable by the manufacture were investigated, representing various reductions in contact area between the stem taper and sleeve taper as well as damage incurred from previous ceramic head fracture. FINDINGS: The largest reduction in fracture strength occurred for a loss of contact for the entire length of the stem taper. Nonetheless, the fracture strength in all investigated cases was several times higher than that defined by the FDA standards. INTERPRETATION: The use of a titanium sleeve recreates a uniform contact situation between the ceramic head and the outer sleeve taper in situations of damaged stem tapers. For the investigated damage types a high fracture strength of the ceramic head was maintained. This study supports the clinical use for sleeved ceramic heads in instances of greater damages of stem tapers than previously defined in order to spare patients from stem removal.