Preliminary clinical and radiological evaluation of osteosynthesis using the Femoral Neck System (FNS) for subcapital fractures of the femur.

Addressing subcapital fractures of the femur poses a substantial clinical challenge, complicated by the diverse range of available osteosynthesis materials. This study is dedicated to a comprehensive analysis of the clinical and radiological implications linked with the implementation of the Femoral Neck System (FNS) in osteosynthesis procedures. A descriptive study was conducted involving patients who underwent osteosynthesis for subcapital fractures of the femur utilizing the FNS during the period from 2019 to 2022. The investigation encompassed various facets, including the classification of fractures according to the Garden and Pauwells classifications, criteria for achieving precise reduction based on the Garden criteria and Tip Apex Distance (TAD). At the one-year follow-up, factors such as fracture consolidation, loss of reduction, fracture collapse, complications, and functional outcomes were evaluated utilizing the Harris Hip Score (HHS) scale. The study cohort included a total of 26 patients, among whom 22 exhibited non-displaced subcapital femur fractures categorized as Garden I and II. Successful reduction was accomplished in 23 cases, in which 24 cases (92.3%) displayed a TAD measurement below 25 mm. According to the HHS, patients achieved an average score of 90.9 (ranging from 63 to 100) following the surgical intervention, with predominantly "excellent" and "good" outcomes. The outcomes derived from our investigation corroborate the viability of the Femoral Neck System (FNS) as a reliable option for osteosynthesis in femoral neck fractures. The results obtained are comparable to those achieved with other available implants, as highlighted by previous studies.

Standard or Fin SIGN® nail? which option is better for the treatment of femoral fractures in low and middle-income countries?

PURPOSE: Femoral fractures are common in low and middle-income countries (LMIC), predominantly caused by high-energy trauma. The surgical implant generation network (SIGN®) program offers two different intramedullary nails in LMIC which are designed to be used without image intensifier free of charge for the patients: the SIGN standard nail (SSN®) and the SIGN Fin nail (SFN®). This study aimed to compare the results of the SSN® and the SFN® for the treatment of middle and distal shaft femoral fractures through a retrograde approach. MATERIAL AND METHODS: This was a retrospective, descriptive, and non-experimental study including all consecutive patients who underwent surgical management of middle or distal shaft femoral fracture between January 2017 and May 2022 in an NGO hospital located in Freetown, Sierra Leone. The duration of surgery, type of reduction, complications like screw loosening, implant migration, anterior knee pain and non-union rate at six months of follow up were evaluated. RESULTS: A total of 122 patients were included in the study. Group A: 60 patients were managed with SSN® and Group B: 62 patients with SFN®. The mean operative time was 104 min with SSN® and 78 with SFN® (p < 0.001). Open reduction of the fracture was necessary in ten (16.7%) patients with SSN® and 12 (19.4%) patients treated with SFN® (p = 0.69). Non-union was observed in one (1.7%) patient with SSN® and two (3.2%) patients with SFN® (p = 0.57). CONCLUSIONS: Both options seem equally effective in treating midshaft and distal femoral shaft fractures. The SFN® reduces the surgical time, due to this fact, in polytraumatized patients, patients with bilateral femur fracture or patients with ipsilateral tibia fracture, it can be considered as the best option to be used. There was no statistical difference in the complications presented by the two groups.

Two novel prehabilitation apps to help patients stop smoking and risky drinking prior to hip and knee arthroplasty.

PURPOSE: Daily smoking or risky drinking increases the risk of complications after surgery by ~50%. Intensive prehabilitation aimed at complete cessation reduces the complication rate but is time-consuming. The purpose of this study was to carry out preoperative pilot tests (randomized design) of the feasibility (1A) and validation (1B) of two novel prehabilitation apps, habeat® (Ha-app) or rehaviour® (Re-app). METHODS: Patients scheduled for hip or knee arthroplasty with daily smoking, risky drinking, or both were randomised to one of the two apps. In part 1A, eight patients and their staff measured feasibility on a visual analog scale (VAS) and were interviewed about what worked well and the challenges requiring improvement. In part 1B, seven patients and their staff tested the improved apps for up to two weeks before validating the understanding, usability, coverage, and empowerment on a VAS and being interviewed. RESULTS: In 1A, all patients and staff returned scores of ≥5 for understanding the apps and mostly suggested technical improvements. In 1B, the scores varied widely for both apps, with no consensus achieved. Two of four patients (Ha-app) and one-third of the patients (Re-app) found the apps helpful for reducing smoking, but without successful quitting. The staff experienced low app competencies among patients and high time consumption. Specifically, patients most often needed help for the Ha-app, and the staff most often for Re-app; however, the staff reported the Re-app dashboard was more user-friendly. Support and follow-up from an addiction specialist staff member were suggested to complement the apps, thereby increasing the time consumption for staff. CONCLUSIONS: This pilot study to test prototype apps generated helpful feedback for the app developers. Based on the patient and staff comments, multiple improvements in functionality seem required before scaling up the evaluation for effect on prehabilitation and postoperative complications.

Contribution of the BioballTM head-neck adapter to the restoration of femoral offset in hip revision arthroplasty with retention of a well-fixed cup and stem.

PURPOSE: Failure to restore the femoral offset of the native hip is a potential cause of dysfunctional hip arthroplasty. The aim of this study was to report our experience of using a modular head-neck adapter in revision THA, specifically analyzing its usefulness as a tool to correct a slightly diminished femoral offset. MATERIALS AND METHODS: This was a retrospective single-center study including all hip revisions performed at our institution from January 2017 to March 2022 where the BioBallTM head-neck metal adapter was used. The preoperative and one year follow-up modified Merle d'Aubigné hip score was used to evaluate functional outcomes. RESULTS: Of a total of 34 cases included for revision, the head-neck adapter system was used specifically in six patients (17.6%) to increase femoral offset, retaining both the acetabular and femoral components. In this subgroup of patients, mean offset decrease after primary THA was 6.6 mm (4.0-9.1), equivalent to a mean 16.3% femoral offset reduction. The median modified Merle d'Aubigné score went from 13.3 preoperatively to 16.2 at one year follow-up. CONCLUSION: The use of a head-neck adapter is a safe and reliable procedure that may allow the surgeon to easily correct a slightly diminished femoral offset in a dysfunctional THA without the need to revise well-fixed prosthetic components.

Antimicrobials in polymethylmethacrylate: from prevention to prosthetic joint infection treatment: basic principles and risk of resistance.

BACKGROUND: Excellent revisions about antibiotic-loaded bone cement (ALBC) have been recently published. In the present article, we review the principles and limitations of local antibiotic delivery in the context of recent advances in the pathogenesis of prosthetic joint infections (PJI), with particular attention paid to the potential association between ALBC and antimicrobial resistance. MAIN BODY: Recalcitrance of PJI is related to the ability of pathogens to adapt to particular environments present in bone tissue and protect themselves from host immunity in different ways. Accordingly, delivery of high local antimicrobial concentrations using ALBC is needed. Most relevant clinical data showing the efficacy of ALBC for PJI prophylaxis and treatment are reviewed, and we dissected the limitations on the basis of the recent findings from animal models and suggested that aminoglycosides, in particular, could not be the best option. One of the major concerns associated with ALBC is the emergence of resistance because of theoretical prolonged exposure to low antibiotic concentrations. We summarize the mechanisms for the selection of resistant microorganisms, and we critically reviewed the evidence from animal models and clinical data from observational and registry studies and concluded that there is no evidence to support this association. CONCLUSION: While waiting for better evidence from well-designed clinical trials, ALBC shows a beneficial effect as a prophylaxis in arthroplasty, and to avoid the colonization of spacers used for two-stage revision in patients with PJI. Experimental models and clinical evidence suggest the need to achieve high local antimicrobial concentrations to obtain the highest prophylactic and therapeutic effect. The current evidence does not support the risk of increasing resistance with use of ALBC. In the future, it is necessary to evaluate new carriers and different antimicrobials to improve clinical outcomes.

Is hip resection arthroplasty a successful definitive treatment?

Purpose: Hip resection arthroplasty as a definitive treatment is an uncommon indication, although still in use selectively. This study evaluates a cohort of patients who have undergone hip resection arthroplasty surgery indicated as a definitive treatment, in order to assess the rate of re-operation, the rate of infection, and the mortality rates. Methods: We conducted a retrospective, observational, descriptive analysis of a cohort of patients who had undergone a hip resection arthroplasty intended as a definitive treatment, in two University Hospitals from 1994 to 2020. The exclusion criteria were the implantation of a hip cement spacer, or a temporary hip resection arthroplasty in patients undergoing a two-staged surgical approach. We found 26 cases of hip resection arthroplasty. We recorded the indications for a definitive hip resection arthroplasty, the outcomes and complications, and analyzed the success of the hip resection arthroplasty as a definitive surgery using a Kaplan-Meier curve. Results: Seven cases (26.9%) required a re-operation after the hip resection arthroplasty, four cases for persistent hip infection, and in the three remaining a conversion to a total hip arthroplasty was re-considered due to a good medical evolution and non-tolerance to the low functional outcome. The mortality rate was 61.5% (27 days-20 years), with a 19.2% mortality rate in the first 5 years. All the cases that required another surgery after the hip resection arthroplasty were re-operated within the first 18 months. Conclusion: Unfortunately, hip resection arthroplasty continues to show elevated re-operation rate and early mortality rate, as well as low functional outcomes. Two-staged hip revision arthroplasty is the surgical treatment of choice in patients suffering from a periprosthetic joint infection, however we believe that hip resection arthroplasty should be considered in fragile patients, who have endured multiple revision surgeries, or their comorbidities make them unfit from further surgeries.

Do Cultures Obtained During Primary THA Predict the Likelihood of Revision?

BACKGROUND: There can be unexpectedly positive culture results during elective hip arthroplasty, but the degree to which these are associated with an increased risk of subsequent premature revision is not known. QUESTION/PURPOSE: Are unexpectedly positive culture results obtained during elective THA associated with an increased likelihood of revision within 5 years of the procedure? METHODS: Between March 2007 and March 2011, the hip unit at our institution performed elective primary THA in 829 patients. We systematically collected three samples in 52% (428 of 829) of the interventions. Of those, 26 patients were excluded because of sampling errors; 94% (402 of 428) had samples that were collected systematically and were eligible for the study. We only considered one hip randomly in bilateral procedures (4% [15 of 428]); patients presenting with acute (< 3 months) periprosthetic joint infection undergoing open debridement (4% [16 of 402]) and patients who died before 5 years of follow-up (2% [seven of 402]) were excluded from the study, leaving 91% (364 of 402) eligible for analysis in this retrospective study of a previous prospective trial. No patient included in the final analysis was lost to follow-up within 5 years from the index surgery. The patient group consisted of 52% (188 of 364) women, with a mean ± SD age of 64.8 ± 13.9 years. RESULTS: Positives culture results were associated with a higher risk of revision within 5 years of the index surgery. The proportion of revision surgery was higher in the group with positive culture results than in those with negative results (10% [eight of 77] versus 2% [seven of 290]; p = 0.01). The difference was mainly attributable to a higher proportion of aseptic loosening in those with positive culture results than in those with negative results (8% [six of 74] versus 1% [four of 290]; p = 0.01). After a multivariable analysis, the only independent variable associated with 5-year revision surgery was the presence of positive results during THA (odds ratio 4.9 [95% confidence interval 1.72 to 13.99]). CONCLUSION: Our findings suggest that bacterial contamination during THA is associated with an increased likelihood of early revision. This higher risk of revision is mainly because of presumed aseptic loosening; thus, efforts should focus on the need to rule out infection. These results not only open new questions that should be answered in new prospective and well-designed studies, but also may help to better select patients to obtain a more favorable outcome after THA. LEVEL OF EVIDENCE: Level III, therapeutic study.

Can the intra-operative measurement of the diameter of the femoral head help surgeons to choose the best size of the acetabular cup?

PURPOSE: We hypothesized that the intra-operative measurement of the femoral head may increase the accuracy of the acetabular cup size optimal selection in total hip arthroplasty (THA). The purpose of this clinical research was to analyze the correlation between the estimated cup size from intra-operative measurement of the femoral head and the pre-operative templated cup size. METHODS: A prospective observational single-center study was conducted from June 2019 to January 2020 including primary THA (n = 100). All cases were pre-operatively templated. The measurement of the anterior-posterior diameter of the femoral head was routinely intra-operatively performed. Any definitive implanted cup was considered as "oversized" when the size was > 4 mm than the diameter of the native head. RESULTS: The median (interquartile range) size of the implanted cup, pre-operative planned cup size, and diameter of the femoral head were measured 52 (50-54) mm, 50 (48-54) mm and 49 (45-51) mm, respectively. Pre-operative planned size cup accurately predicted the implanted cup or differed in only one size (2 mm) in 77 (78%) cases. Otherwise, intra-operative femoral head measurement method accurately predicted the implanted or differed in only one size (2 mm) in 51 (87%) cases (p = 0.097). CONCLUSION: The intra-operative femoral head measurement is a simple and reliable tool to help the surgeons choose the best size of the acetabular cup and is as reliable as the pre-operative templating in order to avoid cup oversizing in THA. Utmost caution is warranted whenever the cup reamer is > 4 mm than the anterior-posterior diameter of the native head.

Usefulness of serum D-dimer and platelet count to mean platelet volume ratio to rule out chronic periprosthetic joint infection.

Background: Diagnosing periprosthetic joint infection (PJI) is challenging and usually requires the evaluation of several biomarkers. Our main aim was to evaluate the usefulness of D-dimer levels as well as the platelet count (PC) to mean platelet volume (MPV) ratio serum as biomarkers to rule out chronic knee and hip infection. Methods: The study enrolled a prospective cohort of 93 patients undergoing hip or knee revision. D-dimer values, PC to MPV ratio, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were preoperatively determined and evaluated as a predictor of PJI. The definitive diagnosis of PJI was established according to the 2018 International Consensus Meeting criteria. Results: A total of 24 (25.8 %) cases were postoperatively diagnosed with PJI. The median D-dimer value was significantly higher ( p   <  0.001) for patients with PJI (1950 ng mL - 1 ) than for patients with aseptic failure (700 ng mL - 1 ). The area under the receiver operating characteristic curves for D-dimer, CRP and ESR was 0.820, 0.793 and 0.791 respectively. D-dimer  ≥  950 ng mL - 1 (91 % sensitivity, 64 % specificity), CRP  ≥  1.95 mg dL - 1 (61 % sensitivity, 90 % specificity) and ESR  >  20 (74 % sensitivity, 82 % specificity) were identified as the values with the best balance between sensitivity and specificity. The mean PC to MPV ratio was 37.0 for PJI patients and 29.8 for patients in the aseptic revision cohort ( p = 0 .067). Conclusions: Serum D-dimer levels appear very unlikely to remain normal in the presence of chronic PJI. The 91 % sensitivity when considering 950 ng mL - 1 as the threshold highlights D-dimer as the most accurate initial test to rule out chronic PJI. Conversely, the PC to MPV ratio may be of limited value for accurately diagnosing PJI.

The Impact of Sex on the Outcomes of Prosthetic Joint Infection Treatment with Debridement, Antibiotics and Implant Retention: A Systematic Review and Individual Patient Data Meta-analysis.

BACKGROUND: The influence of sex on the failure of débridement antibiotics and implant retention (DAIR) for treating prosthetic joint infection (PJI) is important for decision-making, patient counseling, and equitable health care. However, very few studies in the orthopaedic literature conduct sex-specific analyses. AIM: The primary aim was to determine whether sex influences treatment success after DAIR. METHODS: A systematic review and individual patient data (IPD) meta-analysis was conducted. MEDLINE (Ovid), EMBASE (Ovid), Web of Science, and Google Scholar were searched, and IPD was requested via e-mail. Patients who underwent DAIR after developing PJI within 12 months of a primary total hip or knee arthroplasty were included in the analysis. Treatment failure was defined by the Delphi International Consensus criteria. Adjusted odds ratios for treatment failure were calculated using a mixed-effects logistic regression. RESULTS: The study collected and analyzed IPD of 1,116 patients from 21 cohorts. The odds of treatment failure were 29% lower in women (odds ratio, 0.71; 95% CI 0.54 to 0.017; P = 0.017), after adjusting for duration of symptoms >7 days and Staphylococcus aureus infection (methicillin-susceptible Staphylococcus aureus or any infection with S aureus). None of the 64 studies included in the systematic review conducted a sex-specific analysis. CONCLUSION: For patients who developed a PJI within 1 year postsurgery, females have lower odds of DAIR failure than males. Other factors also have varying effects on outcome for men and women. It is essential to implement sex-specific analysis in orthopaedic research.

Prognosis of unexpected positive intraoperative cultures in arthroplasty revision: A large multicenter cohort.

BACKGROUND: The positive-intraoperative-cultures-type prosthetic joint infection (PIOC-PJI) is considered when surgical cultures yield microorganisms in presumed aseptic arthroplasty revisions. Herein we assess the risk factors for failure in the largest cohort of PIOC-PJI patients reported to date. METHODS: A retrospective, observational, multicenter study was performed during 2007-2017. Surgeries leading to diagnose PIOC-PJI included only one-stage procedures with either complete or partial prosthesis revision. Failure was defined as recurrence caused by the same microorganism. RESULTS: 203 cases were included (age 72 years, 52% females). Coagulase-negative staphylococci (n = 125, 62%) was the main etiology, but some episodes were caused by virulent bacteria (n = 51, 25%). Prosthesis complete and partial revision was performed in 93 (46%) and 110 (54%) cases, respectively. After a median of 3.4 years, failure occurred in 17 episodes (8.4%, 95%CI 5.3-13.1). Partial revision was an independent predictor of failure (HR 3.63; 95%CI 1.03-12.8), adjusted for gram-negative bacilli (GNB) infection (HR 2.68; 95%CI 0.91-7.89) and chronic renal impairment (HR 2.40; 95%CI 0.90-6.44). Treatment with biofilm-active antibiotics (rifampin/fluoroquinolones) had a favorable impact on infections caused by staphylococci and GNB. CONCLUSION: Overall prognosis of PIOC-PJI is good, but close follow-up is required in cases of partial revision and in infections caused by GNB.

Fluorescent tetracycline bone labeling as an intraoperative tool to debride necrotic bone during septic hip revision: a preliminary case series.

A plausible cause of persistent infection after septic hip revision may be the presence of nonviable osteomyelitic bone. Since surgical excision of these necrotic fragments is often challenging, the use of fluorescent tetracycline bone labeling (FTBL) as an intraoperative tool may pose an additional assessment aid to provide a visual index of surgical debridement. Methods: We present a single-center study performed in a university hospital from January 2018 to June 2020, in which all consecutive cases of chronic hip periprosthetic joint infection (PJI) undergoing revision using FTBL were retrospectively reviewed. In all cases, the patient was under treatment with tetracyclines at the moment of the revision surgery. During the surgery, all bone failing to fluoresce was considered nonviable and thus removed and sent for both culture and histology. Results: We include three cases in which the FTBL technique was used. In all cases, the histopathological examinations of the nonfluorescent removed bone were consistent with chronic osteomyelitis. Conclusion: The intraoperative use of FTBL successfully aided the surgeon to detect the presence of nonviable bone in all the presented cases of chronic prosthetic hip infection.

One-Stage Hip Revision Arthroplasty Using Megaprosthesis in Severe Bone Loss of The Proximal Femur Due to Radiological Diffuse Osteomyelitis.

Managing substantial proximal and/or distal femoral bone defects is one of the biggest challenges in chronic hip periprosthetic joint infection. Most authors use two-stage arthroplasty with a temporary antibiotic-loaded cement spacer for the management of these patients. In this study, we show our experience with one-stage exchange arthroplasty in managing severe bone defects due to radiological-extensive proximal femoral osteomyelitis. Two patients were included in the study. They showed radiological-extensive proximal femoral osteomyelitis, and they were treated with one-stage exchange arthroplasty using megaprosthesis. Diffuse osteomyelitis was confirmed in both cases; in one case, the histology was compatible with osteomyelitis, and the other case had a positive culture identified in a bone sample. At a minimum of a four-year follow-up, the patients did not reveal any clinical, radiological or laboratory signs of infection. In conclusion, one-stage exchange arthroplasty and megaprosthesis is an option for the treatment of chronic hip periprosthetic joint infection associated with radiological-diffuse proximal femoral osteomyelitis.

Outcomes of hip arthroplasty with concomitant hardware removal: influence of the type of implant retrieved and impact of positive intraoperative cultures.

INTRODUCTION: The impact of residual internal fixation devices on subsequent procedures about the hip has not been clearly well defined. The objective of the current study is to evaluate the outcome of hip arthroplasty after hardware retrieval as a one-stage replacement, to analyze possible differences related to the type of removed implant, and to assess the impact of unexpected intraoperative cultures during implant retrieval. MATERIALS AND METHODS: We present a retrospective study including all those cases undergoing hip arthroplasty with concomitant hardware removal (cannulated screws, intramedullary nail, or dynamic hip screw) from 2005 to 2018. We evaluated demographics, intraoperative cultures, early infection rate, and other complications. RESULTS: A total of 55 cases were included in the study. The median time between the implant surgery and the hip arthroplasty was 113 days. The removed devices included 6 cannulated screws, 34 intramedullary nails, and 15 dynamic hip screws. Up to 74.5% of the failed osteosynthesis belonged to intertrochanteric femoral fractures. Dislocation rate was 9.1% (1.8% requiring revision surgery), 25.5% of the cases needed further new surgeries after the hip arthroplasty, and 49.1% died during the follow-up period. Any-cause revision surgery and mortality rates were significantly increased after intramedullary nail removal. Intraoperative cultures were performed in 46 cases, and in 9 (16.4%), there was bacterial contamination: 6 cases (10.9%) presented one single positive culture and 3 (5.5%) presented ≥ 2 positive cultures for the same microorganism. A total of five cases (9.1%) presented early prosthetic joint infection that required debridement. None of these five cases had presented positive cultures at the implant removal. CONCLUSION: According to our results, hip arthroplasty with concomitant hardware removal is related to a high 5-year mortality rate, mainly when intramedullary nail is retrieved. Whereas a high risk of early prosthetic joint infection is associated, it seems not to be related to the elevated presence of unexpected positive cultures.

Removal of protruding screws in a painful total hip arthroplasty: A case report.

Persistent pain after total hip arthroplasty can be challenging for the orthopedic surgeon. We present a case of a 56-year-old female with an uncommon cause of persistent pain after total hip replacement, due to protruding screws with the subsequent impingement of surrounding soft tissues. The patient presented persistent groin pain after total hip revision surgery. After ruling out infection and loosening, an infiltration of iliopsoas muscle was performed, with only temporary improvement. The magnetic resonance depicted the conflict of the screws with the surrounding soft tissues, in close relation to the iliopsoas muscle, the external obturator muscle and the sciatic nerve. Revision surgery was performed, removing the screws, and implanting a new liner with complete remission of symptoms. Our case presents an atypical cause of pain due to surrounding tissue lesions by offending screws with complete resolution after only screw removal. In the clinical study of persistent pain following a total hip replacement, screws length, and protrusion should be considered and ruled out as a possible and treatable etiology. Removal of the screws after cup integration can be a conservative and effective strategy to treat the pain.

Compresión medular por inestabilidad atlantoaxoidea en artritis reumatoide / Medullar compression due to an atlantoaxial instability in rheumatoid arthritis

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Prevalence and Impact of Positive Intraoperative Cultures in Partial Hip or Knee Revision.

BACKGROUND: Our aim is to investigate the impact of unexpected positive cultures on the outcome of partial prosthetic revisions. METHODS: Data regarding patients who underwent a partial hip or knee revision from 2003 and 2012 with the preoperative diagnosis of aseptic loosening was retrospectively reviewed. The protocol of revision included at least 3 intraoperative cultures. Failure was defined as the need for re-revision due to aseptic or septic loosening at 5 years. RESULTS: A total of 99 hip and 46 knee partial revisions were included. All cases had at least 5 years of follow-up. Ninety-seven cases (66.9%) had all cultures negative, 35 (24.1%) a single positive culture and 13 (9.0%) ≥2 positive cultures for the same microorganism. The median time from primary arthroplasty to partial revision was significantly shorter for patients with ≥2 positive cultures (26 months) than in those with all cultures negative (48 months) or with a single positive culture (51 months). Partial revisions performed within the first 5 years of implantation had a higher 5-year re-revision rate. The presence of a single positive culture during the partial exchange was not associated with a higher re-revision rate (2 of 35, 5.7%) than in those with negative cultures (3 of 97, 3.1%). On the contrary, re-revision rate was significantly higher in cases with ≥2 positive cultures (3 of 13, 23.1%) than in those with negative cultures (P = .02). CONCLUSION: Partial revisions performed within the first 5 years from implantation and ≥2 intraoperative positive cultures were associated with a higher re-revision risk at 5 years.