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The Bone & Joint Journal
Vol. 106-B, Issue 8 | Pages 775 - 782
1 Aug 2024
Wagner M Schaller L Endstrasser F Vavron P Braito M Schmaranzer E Schmaranzer F Brunner A

Aims

Hip arthroscopy has gained prominence as a primary surgical intervention for symptomatic femoroacetabular impingement (FAI). This study aimed to identify radiological features, and their combinations, that predict the outcome of hip arthroscopy for FAI.

Methods

A prognostic cross-sectional cohort study was conducted involving patients from a single centre who underwent hip arthroscopy between January 2013 and April 2021. Radiological metrics measured on conventional radiographs and magnetic resonance arthrography were systematically assessed. The study analyzed the relationship between these metrics and complication rates, revision rates, and patient-reported outcomes.


The Bone & Joint Journal
Vol. 106-B, Issue 8 | Pages 792 - 801
1 Aug 2024
Kleeman-Forsthuber L Kurkis G Madurawe C Jones T Plaskos C Pierrepont JW Dennis DA

Aims

Spinopelvic pathology increases the risk for instability following total hip arthroplasty (THA), yet few studies have evaluated how pathology varies with age or sex. The aims of this study were: 1) to report differences in spinopelvic parameters with advancing age and between the sexes; and 2) to determine variation in the prevalence of THA instability risk factors with advancing age.

Methods

A multicentre database with preoperative imaging for 15,830 THA patients was reviewed. Spinopelvic parameter measurements were made by experienced engineers, including anterior pelvic plane tilt (APPT), spinopelvic tilt (SPT), sacral slope (SS), lumbar lordosis (LL), and pelvic incidence (PI). Lumbar flexion (LF), sagittal spinal deformity, and hip user index (HUI) were calculated using parameter measurements.


The Bone & Joint Journal
Vol. 106-B, Issue 8 | Pages 802 - 807
1 Aug 2024
Kennedy JW Sinnerton R Jeyakumar G Kane N Young D Meek RMD

Aims

The number of revision arthroplasties being performed in the elderly is expected to rise, including revision for infection. The primary aim of this study was to measure the treatment success rate for octogenarians undergoing revision total hip arthroplasty (THA) for periprosthetic joint infection (PJI) compared to a younger cohort. Secondary outcomes were complications and mortality.

Methods

Patients undergoing one- or two-stage revision of a primary THA for PJI between January 2008 and January 2021 were identified. Age, sex, BMI, American Society of Anesthesiologists grade, Charlson Comorbidity Index (CCI), McPherson systemic host grade, and causative organism were collated for all patients. PJI was classified as ‘confirmed’, ‘likely’, or ‘unlikely’ according to the 2021 European Bone and Joint Infection Society criteria. Primary outcomes were complications, reoperation, re-revision, and successful treatment of PJI. A total of 37 patients aged 80 years or older and 120 patients aged under 80 years were identified. The octogenarian group had a significantly lower BMI and significantly higher CCI and McPherson systemic host grades compared to the younger cohort.


The Bone & Joint Journal
Vol. 106-B, Issue 8 | Pages 783 - 791
1 Aug 2024
Tanaka S Fujii M Kawano S Ueno M Nagamine S Mawatari M

Aims

The aim of this study was to determine the clinical outcomes and factors contributing to failure of transposition osteotomy of the acetabulum (TOA), a type of spherical periacetabular osteotomy, for advanced osteoarthritis secondary to hip dysplasia.

Methods

We reviewed patients with Tönnis grade 2 osteoarthritis secondary to hip dysplasia who underwent TOA between November 1998 and December 2019. Patient demographic details, osteotomy-related complications, and the modified Harris Hip Score (mHHS) were obtained via medical notes review. Radiological indicators of hip dysplasia were assessed using preoperative and postoperative radiographs. The cumulative probability of TOA failure (progression to Tönnis grade 3 or conversion to total hip arthroplasty) was estimated using the Kaplan-Meier product-limited method. A multivariate Cox proportional hazards model was used to identify predictors of failure.


Bone & Joint Open
Vol. 5, Issue 7 | Pages 560 - 564
7 Jul 2024
Meißner N Strahl A Rolvien T Halder AM Schrednitzki D

Aims

Transfusion after primary total hip arthroplasty (THA) has become rare, and identification of causative factors allows preventive measures. The aim of this study was to determine patient-specific factors that increase the risk of needing a blood transfusion.

Methods

All patients who underwent elective THA were analyzed retrospectively in this single-centre study from 2020 to 2021. A total of 2,892 patients were included. Transfusion-related parameters were evaluated. A multiple logistic regression was performed to determine whether age, BMI, American Society of Anesthesiologists (ASA) grade, sex, or preoperative haemoglobin (Hb) could predict the need for transfusion within the examined patient population.


The Bone & Joint Journal
Vol. 106-B, Issue 7 | Pages 656 - 661
1 Jul 2024
Bolbocean C Hattab Z O'Neill S Costa ML

Aims

Cemented hemiarthroplasty is an effective form of treatment for most patients with an intracapsular fracture of the hip. However, it remains unclear whether there are subgroups of patients who may benefit from the alternative operation of a modern uncemented hemiarthroplasty – the aim of this study was to investigate this issue. Knowledge about the heterogeneity of treatment effects is important for surgeons in order to target operations towards specific subgroups who would benefit the most.

Methods

We used causal forest analysis to compare subgroup- and individual-level treatment effects between cemented and modern uncemented hemiarthroplasty in patients aged > 60 years with an intracapsular fracture of the hip, using data from the World Hip Trauma Evaluation 5 (WHiTE 5) multicentre randomized clinical trial. EuroQol five-dimension index scores were used to measure health-related quality of life at one, four, and 12 months postoperatively.


Bone & Joint Open
Vol. 5, Issue 6 | Pages 514 - 523
24 Jun 2024
Fishley W Nandra R Carluke I Partington PF Reed MR Kramer DJ Wilson MJ Hubble MJW Howell JR Whitehouse SL Petheram TG Kassam AM

Aims

In metal-on-metal (MoM) hip arthroplasties and resurfacings, mechanically induced corrosion can lead to elevated serum metal ions, a local inflammatory response, and formation of pseudotumours, ultimately requiring revision. The size and diametral clearance of anatomical (ADM) and modular (MDM) dual-mobility polyethylene bearings match those of Birmingham hip MoM components. If the acetabular component is satisfactorily positioned, well integrated into the bone, and has no surface damage, this presents the opportunity for revision with exchange of the metal head for ADM/MDM polyethylene bearings without removal of the acetabular component.

Methods

Between 2012 and 2020, across two centres, 94 patients underwent revision of Birmingham MoM hip arthroplasties or resurfacings. Mean age was 65.5 years (33 to 87). In 53 patients (56.4%), the acetabular component was retained and dual-mobility bearings were used (DM); in 41 (43.6%) the acetabulum was revised (AR). Patients underwent follow-up of minimum two-years (mean 4.6 (2.1 to 8.5) years).


Bone & Joint Research
Vol. 13, Issue 6 | Pages 294 - 305
17 Jun 2024
Yang P He W Yang W Jiang L Lin T Sun W Zhang Q Bai X Sun W Guo D

Aims

In this study, we aimed to visualize the spatial distribution characteristics of femoral head necrosis using a novel measurement method.

Methods

We retrospectively collected CT imaging data of 108 hips with non-traumatic osteonecrosis of the femoral head from 76 consecutive patients (mean age 34.3 years (SD 8.1), 56.58% male (n = 43)) in two clinical centres. The femoral head was divided into 288 standard units (based on the orientation of units within the femoral head, designated as N[Superior], S[Inferior], E[Anterior], and W[Posterior]) using a new measurement system called the longitude and latitude division system (LLDS). A computer-aided design (CAD) measurement tool was also developed to visualize the measurement of the spatial location of necrotic lesions in CT images. Two orthopaedic surgeons independently performed measurements, and the results were used to draw 2D and 3D heat maps of spatial distribution of necrotic lesions in the femoral head, and for statistical analysis.


Bone & Joint Open
Vol. 5, Issue 6 | Pages 479 - 488
6 Jun 2024
Paksoy A Meller S Schwotzer F Moroder P Trampuz A Imiolczyk J Perka C Hackl M Plachel F Akgün D

Aims

Current diagnostic tools are not always able to effectively identify periprosthetic joint infections (PJIs). Recent studies suggest that circulating microRNAs (miRNAs) undergo changes under pathological conditions such as infection. The aim of this study was to analyze miRNA expression in hip arthroplasty PJI patients.

Methods

This was a prospective pilot study, including 24 patients divided into three groups, with eight patients each undergoing revision of their hip arthroplasty due to aseptic reasons, and low- and high-grade PJI, respectively. The number of intraoperative samples and the incidence of positive cultures were recorded for each patient. Additionally, venous blood samples and periarticular tissue samples were collected from each patient to determine miRNA expressions between the groups. MiRNA screening was performed by small RNA-sequencing using the miRNA next generation sequencing (NGS) discovery (miND) pipeline.


Bone & Joint Research
Vol. 13, Issue 6 | Pages 272 - 278
5 Jun 2024
Niki Y Huber G Behzadi K Morlock MM

Aims

Periprosthetic fracture and implant loosening are two of the major reasons for revision surgery of cementless implants. Optimal implant fixation with minimal bone damage is challenging in this procedure. This pilot study investigates whether vibratory implant insertion is gentler compared to consecutive single blows for acetabular component implantation in a surrogate polyurethane (PU) model.

Methods

Acetabular components (cups) were implanted into 1 mm nominal under-sized cavities in PU foams (15 and 30 per cubic foot (PCF)) using a vibratory implant insertion device and an automated impaction device for single blows. The impaction force, remaining polar gap, and lever-out moment were measured and compared between the impaction methods.


The Bone & Joint Journal
Vol. 106-B, Issue 6 | Pages 565 - 572
1 Jun 2024
Resl M Becker L Steinbrück A Wu Y Perka C

Aims

This study compares the re-revision rate and mortality following septic and aseptic revision hip arthroplasty (rTHA) in registry data, and compares the outcomes to previously reported data.

Methods

This is an observational cohort study using data from the German Arthroplasty Registry (EPRD). A total of 17,842 rTHAs were included, and the rates and cumulative incidence of hip re-revision and mortality following septic and aseptic rTHA were analyzed with seven-year follow-up. The Kaplan-Meier estimates were used to determine the re-revision rate and cumulative probability of mortality following rTHA.


The Bone & Joint Journal
Vol. 106-B, Issue 6 | Pages 548 - 554
1 Jun 2024
Ohyama Y Minoda Y Masuda S Sugama R Ohta Y Nakamura H

Aims

The aim of this study was to compare the pattern of initial fixation and changes in periprosthetic bone mineral density (BMD) between patients who underwent total hip arthroplasty (THA) using a traditional fully hydroxyapatite (HA)-coated stem (T-HA group) and those with a newly introduced fully HA-coated stem (N-HA group).

Methods

The study included 36 patients with T-HA stems and 30 with N-HA stems. Dual-energy X-ray absorptiometry was used to measure the change in periprosthetic BMD, one and two years postoperatively. The 3D contact between the stem and femoral cortical bone was evaluated using a density-mapping system, and clinical assessment, including patient-reported outcome measurements, was recorded.


The Bone & Joint Journal
Vol. 106-B, Issue 6 | Pages 540 - 547
1 Jun 2024
Nandra RS Elnahal WA Mayne A Brash L McBryde CW Treacy RBC

Aims

The Birmingham Hip Resurfacing (BHR) was introduced in 1997 to address the needs of young active patients using a historically proven large-diameter metal-on-metal (MoM) bearing. A single designer surgeon’s consecutive series of 130 patients (144 hips) was previously reported at five and ten years, reporting three and ten failures, respectively. The aim of this study was to extend the follow-up of this original cohort at 25 years.

Methods

The study extends the reporting on the first consecutive 144 resurfacing procedures in 130 patients for all indications. All operations were undertaken between August 1997 and May 1998. The mean age at operation was 52.1 years (SD 9.93; 17 to 76), and included 37 female patients (28.5%). Failure was defined as revision of either component for any reason. Kaplan-Meier survival analysis was performed. Routine follow-up with serum metal ion levels, radiographs, and Oxford Hip Scores (OHSs) was undertaken.


The Bone & Joint Journal
Vol. 106-B, Issue 6 | Pages 555 - 564
1 Jun 2024
Leal J Holland CT Cochrane NH Seyler TM Jiranek WA Wellman SS Bolognesi MP Ryan SP

Aims

This study aims to assess the relationship between history of pseudotumour formation secondary to metal-on-metal (MoM) implants and periprosthetic joint infection (PJI) rate, as well as establish ESR and CRP thresholds that are suggestive of infection in these patients. We hypothesized that patients with a pseudotumour were at increased risk of infection.

Methods

A total of 1,171 total hip arthroplasty (THA) patients with MoM articulations from August 2000 to March 2014 were retrospectively identified. Of those, 328 patients underwent metal artefact reduction sequence MRI and had minimum two years’ clinical follow-up, and met our inclusion criteria. Data collected included demographic details, surgical indication, laterality, implants used, history of pseudotumour, and their corresponding preoperative ESR (mm/hr) and CRP (mg/dl) levels. Multivariate logistic regression modelling was used to evaluate PJI and history of pseudotumour, and receiver operating characteristic curves were created to assess the diagnostic capabilities of ESR and CRP to determine the presence of infection in patients undergoing revision surgery.


Bone & Joint Open
Vol. 5, Issue 5 | Pages 394 - 400
15 May 2024
Nishi M Atsumi T Yoshikawa Y Okano I Nakanishi R Watanabe M Usui Y Kudo Y

Aims

The localization of necrotic areas has been reported to impact the prognosis and treatment strategy for osteonecrosis of the femoral head (ONFH). Anteroposterior localization of the necrotic area after a femoral neck fracture (FNF) has not been properly investigated. We hypothesize that the change of the weight loading direction on the femoral head due to residual posterior tilt caused by malunited FNF may affect the location of ONFH. We investigate the relationship between the posterior tilt angle (PTA) and anteroposterior localization of osteonecrosis using lateral hip radiographs.

Methods

Patients aged younger than 55 years diagnosed with ONFH after FNF were retrospectively reviewed. Overall, 65 hips (38 males and 27 females; mean age 32.6 years (SD 12.2)) met the inclusion criteria. Patients with stage 1 or 4 ONFH, as per the Association Research Circulation Osseous classification, were excluded. The ratios of anterior and posterior viable areas and necrotic areas of the femoral head to the articular surface were calculated by setting the femoral head centre as the reference point. The PTA was measured using Palm’s method. The association between the PTA and viable or necrotic areas of the femoral head was assessed using Spearman’s rank correlation analysis (median PTA 6.0° (interquartile range 3 to 11.5)).


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 16 - 16
2 May 2024
McCann C Brunt A Walmsley P Akhtar A
Full Access

There is an increasing demand worldwide for total hip arthroplasty in patients over 80 years old. This study is the largest of its kind reporting long term outcomes and clinical survivorship of patients over 80 years old undergoing THR.

13171 patients 80 years or older who underwent THR between 2000 and 2019 were included. Demographic and operative data was collected including age, sex, laterality, date of surgery and operative technique. Presence and date of complications were collected. Data was also collected for the same time period on 80910 patients aged 51–79 years undergoing THR for comparison.

4103 (31.2%) male and 9068 female (68.8%) patients were included in the 80year old cohort. Median age was 83 (IQR 81–83, range 80–98). 32682 (40.4%) male and 48227 (59.6%) females were included in the 50–79year old cohort. Median age was 68 (IQR 62–73, range 50–79).

The 80 cohort was more likely to sustain post operative complications in the 6 months following surgery including DVT (81/13171 vs 364/80910, P<0.05), myocardial infarction (177/13171 vs 341/80910, P<0.05), acute renal failure (371/12800 vs 812/80910 P<0.05).

The 50–79year old cohort was over twice as likely to undergo revision surgery than the 80 year old cohort (HR 2.55, 95% CI 2.216–2.932, p<0.001). Of those requiring revision surgery, the elderly cohort were more likely to undergo earlier revision surgery (378days, 95%CI 236–519d vs 1586days, 95%CI 1471–1700d, p<0.001). In those undergoing revision surgery, a higher proportion were done for infection in the 80 year old cohort (39/219 (17.8%) vs 215/2809 (7.7%), p<0.05.

This study demonstrates good outcomes in terms of medical complications and a low overall risk of requiring revision surgery in patients 80years old undergoing THR. Patients over the age of 80 should be counselled on the relatively increased risk of medical complications post operatively.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 29 - 29
2 May 2024
Gibbs V Champaneria R Sandercock J Welton N Geneen L Brunskill S Doree C Kimber C Palmer A Estcourt L
Full Access

Preoperative anaemia and intraoperative blood loss result in ∼90% of individuals being anaemic following hip and knee arthroplasty. Reducing blood loss offers the opportunity to improve outcomes and reduce the risk of transfusion and costs. This review's aim was to determine the effectiveness of drugs for preventing blood loss, and identify optimal dose, route, and timing of administration.

Cochrane network meta-analysis of randomised controlled trials was conducted. Inclusion criteria: adults undergoing primary or revision elective hip or knee arthroplasty. Drugs studied: tranexamic acid (TXA), aprotinin, epsilon-aminocaproic acid, desmopressin, factor VIIa and XIII, fibrinogen, fibrin sealants, and non-fibrin sealants. Primary outcomes: need for allogenic blood transfusion, all• cause mortality (within 30 days). Secondary outcomes: mean number of transfusion episodes, re-operation, length of hospital stay and adverse events (DVT, PE, CVA, MI).

102 studies with 8418 participants. Trials included more women (63%). 47 studies (4398 participants) were included within the blood transfusion NMA. TXA given intra-articularly and orally at a total dose of greater than 3g pre-incision, intraoperatively and postoperatively ranked the highest, with anticipated absolute effect of 147 fewer transfusions per 1000 (53% chance ranking 1st) (relative risk(RR) 0.02, 95% credible interval(CrI) 0–0.31); moderate-certainty). Aprotinin (RR 0.59, 95%:CrI 0.36–0.86; low certainty evidence), fibrin (RR 0.86, CrI 0.25–2.93; very-low certainty) and EACA (RR 0.60, 95%:CrI 0.29–1.27; very-low certainty) were not shown to be as effective as TXA.

TXA was the most effective drug for preventing bleeding in lower limb arthroplasty. Aprotinin and EACA were not as effective. Currently, the optimal dose, route and timing of administration of TXA is unclear. However, TXA given at higher doses and via mixed routes ranked higher in the treatment hierarchy. Oral TXA may be as effective as intavenous. There was no evidence of harm associated with higher doses of TXA.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 30 - 30
2 May 2024
Dhesi E Salih S Tomlinson R Salih S
Full Access

Polymethylmethacrylate (PMMA) bone cement is strong in compression, however it tends to fail under torsion. Sufficient pressurisation and subsequent interdigitation between cement and bone are critical for the mechanical interlock of cemented orthopaedic implants, and an irregular surface on the acetabular cup is necessary for reasonable fixation at the cup-cement interface. There is limited literature investigating discrepancies in the failure mechanisms of cemented all-polyethylene acetabular cups with and without cement spacers, under torsional loading.

In vitro experimental comparison of three groups of polyethylene acetabular prosthesis (PAP) cemented into prepared sawbone hemipelvises:

* PAP without PMMA spacers maintaining an equal cement mantle circumferentially. (Group 1 n=3)

* PAP without PMMA spacers cemented deliberately ‘bottoming-out’ the implant within the acetabulum. (Group 2 n=3)

* PAP with PMMA spacers. (Group 3 n=3)

The constructs were tested to torstional failure on a custom designed setup, and statistical analysis done by a one-way ANOVA and Tukey-Welsh test.

Group 3 demonstrated superior torsional resistance with a statistically significant torque of 145Nm (SD±12Nm) at failure, compared to group 2 (109Nm, SD±7Nm) and group 1 (99Nm, SD±8Nm). Group 3 experienced failure predominantly at the bone-cement interface, in contrast, Groups 1 and 2 exhibited failure predominantly at the cup-cement interface. There was no significant difference between Group 1 and 2. Qualitative analysis of the failure mode indicates the efficient redistribution of stress throughout the cement mantle, consistent with the greater uniformity of cement.

PMMA spacers increase the resistance to torsional failure at the implant-cement interface. Acetabular components without spacers (Groups 1 and 2) failed at the implant-cement interface before the cement-bone interface, at a statistically significantly lower level of torque to failure. Although the PMMA spacers may reduce cement interdigitation at the cement-bone interface the torsional forces required to fail are likely supraphysiological.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 52 - 52
2 May 2024
Bayram JM Wickramasinghe N Scott CE Clement ND
Full Access

The aims were to assess whether preoperative joint-specific function (JSF) and health-related quality of life (HRQoL) were associated with level of clinical frailty in patients waiting for a primary total hip arthroplasty (THA) or knee arthroplasty (KA).

Patients waiting for a THA (n=100) or KA (n=100) for more than six months were prospectively recruited from the study centre. Overall, 162 patients responded to the questionnaire (81 THA; 81 KA). Patient demographics, Oxford score, EuroQol five dimension (EQ-5D) score, EuroQol visual analogue score (EQ-VAS), Rockwood Clinical Frailty Score (CFS), and time spent on the waiting list were collected.

There was a significant correlation between CFS and the Oxford score (THA r=ˆ’0.838; p<0.001, KA r=ˆ’0.867; p<0.001), EQ-5D index (THA r=ˆ’0.663, p<0.001; KA r=ˆ’0.681; p< 0.001), and EQ-VAS (THA r=ˆ’0.414; p<0.001, KA r=ˆ’0.386; p<0.001). Confounding variables (demographics and waiting time) where adjusted for using multiple regression analysis. For each 8.5 (THA, 95% CI 7.1 to 10.0; p<0.001) and 9.9 (KA, 95% CI 8.4 to 11.4; p<0.001) point change in the Oxford score, there was an associated change in level of the CFS. For each 0.16 (THA, 95% CI 0.10 to 0.22; p<0.001) and 0.20 (KA, 95% CI 0.12 to 0.27; p<0.001) utility change in EQ-5D, there was an associated change in level of the CFS. EQ-VAS (THA, B=ˆ’11.5; p<0.001, KA B=ˆ’7.9; p=0.005) was also associated with CFS.

JSF and HRQoL in patients awaiting THA or KA for more than six months, were independently associated with level of clinical frailty. With further prospective studies, clinical frailty may prove to be a useful metric to assist in the prioritization of arthroplasty waiting lists.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 47 - 47
2 May 2024
Kolhe S Khanduja V Malviya A
Full Access

Hip arthroscopy (HA) is an effective treatment for various hip conditions but has a steep learning curve and its effect on long-term joint preservation is unclear. This study uses population-level data to assess (1) the 90-day complication rate, and (2) the frequency and timing of revision HA, total hip replacement (THR), and pelvic osteotomy (PO) following primary HA.

We performed a retrospective analysis of the National Hospital Episode Statistics database, examining all patients who underwent primary HA in NHS hospitals in England from 2010 to 2023 using relevant OPCS-4 codes. We evaluated patient demographics, 90-day complications, and reoperation rates for revision HA, THR, and PO. Descriptive statistical analyses were performed to calculate frequencies and average time to reoperations.

We included 22,401 HA procedures in the study. The mean LOS was 0.82±2.04 days. The 90-day readmission rate was 0.17% at a mean of 54.4±8.1 days. The most common reasons for readmission were reoperation (0.071%), followed by infection (0.031%), pulmonary embolism (0.027%), pain (0.022%), bleeding (0.018%), and deep vein thrombosis (0.004%). One patient died within 90 days.

Overall, 4942 patients (22.1%) required further surgery at a mean of 2.71±2.27 years. The rates of revision HA, conversion to THR, and PO were 6.94%, 14.6%, and 0.50% at a mean of 2.39±1.79, 2.87±2.46, and 2.26±1.80 years respectively. Female patients had higher rates of reoperation than males for conversion to THR (9.99% vs 4.63%), revision HA (4.92% vs 2.02%), and subsequent PO (0.43% vs. 0.06%) (p<0.001).

This study demonstrates a low short-term complication rate after primary HA, supporting existing literature. However, a large proportion of patients required further surgery, especially females. These findings highlight the need for careful patient selection and counselling before HA to optimise outcomes, as well as further research on factors influencing longer-term outcomes and cost-effectiveness.