Background/Objectives: As the rate of revision total hip arthroplasty (THA) has risen, there has been a drive to improve the technology in the manufacturing of the implants used. One recent advance has been 3-D printing of trabecular titanium implants to improve implant stability and osteointegration. The aim of this study was to review the clinical and radiological outcomes of these acetabular implants in revision THA. Methods: A manual search of the databases of the US National Library of medicine (PubMed/MEDLINE), Embase, and the Cochrane library was performed. The following keywords of “revision total hip arthroplasty” AND “acetabulum” AND “titanium” AND “porous” were utilised. Results: In total, 106 abstracts were identified during manual search of databases. In total, 11 studies reporting 4 different implants, with a total of 597 operated joints in 585 patients were included in this review. There were 349 (59.7%) female patients, and the mean age per study ranged from 56.0 to 78.4 years. The all-cause survival rate was 95.52% (95% CI: 92.37–97.96) at a mean follow up of 3.8 years (95% CI: 2.6–5.1). The 40 cases that required re-operation included 17 (2.8%) for infection, 14 (2.3%) instability, 2 (0.3%) for shell migration and 5 (0.8%) for aseptic loosening. The most commonly used patient reported outcome measure was the Harris Hip Score with the mean post-operative score of 86.7 (95% CI: 84.3–89.1). Conclusions: Trabecular titanium acetabular implants, when used in revision THA, resulted in excellent short- to mid-term outcomes with improved hip specific outcomes and a survivorship of 95.52% over the reported follow-up period. Future prospective studies evaluating long term outcomes are needed to make comparisons between more established solutions used in revision THA.

Aims: Unicompartmental knee arthroplasty (UKA) is associated with an accelerated recovery, improved functional outcomes, and retention of anatomical knee kinematics when compared to manual total knee arthroplasty (mTKA). UKA is not universally employed by all surgeons as there is a higher revision risk when compared to mTKA. Robotic arm-assisted (ra) UKA enables the surgeon to position the prosthesis more accurately when compared to manual UKA, and is associated with improved functional outcomes and a lower early revision risk. Non-randomized data suggests that, when compared to mTKA, raUKA has a clinically meaningful greater functional benefit. This protocol describes a randomized controlled trial that aims to evaluate the clinical and cost-effectiveness of raUKA compared to mTKA for individuals with isolated medial compartment osteoarthritis (OA). Methods: The total versus robotic-assisted unicompartmental knee arthroplasty (TRAKER) trial is a patient- and assessor-blinded, pragmatic parallel two-arm randomized superiority trial of adults undergoing elective primary knee arthroplasty for primary medial compartment OA at a single NHS hospital (ClinicalTrials.gov NCT05290818). Participants will be randomly allocated on a 1:2 basis to either raUKA or mTKA, respectively. The primary analysis will compare the Oxford Knee Score (OKS) six months after surgery. Secondary outcomes measured at three, six, and 12 months include the OKS, Forgotten Joint Score, patient expectations, EuroQol five-dimension questionnaire (EQ-5D), and EQ-visual analogue scale (EQ-VAS), patient satisfaction, range of motion, postoperative complications, need for further surgery, resource use, and financial costs. Cost-effectiveness will be measured over a ten-year time span. A total of 159 patients will be randomized (n = 53 raUKA vs n = 106 mTKA) to obtain 80% power to detect a five-point difference in OKS between the groups six months after surgery. Conclusion: The trial findings will provide evidence about the clinical and cost-effectiveness of raUKA compared to mTKA in patients with isolated medial compartment OA. This will inform future National Institute for Health and Care Excellence guidelines on primary knee arthroplasty in the UK. Cite this article: Bone Jt Open 2025;6(2):164–177.

Aims The primary aim of this study is to assess the survival of the uncemented hydroxyapatite (HA) coated Trident II acetabular component as part of a hybrid total hip arthroplasty (THA) using a cemented Exeter stem. The secondary aims are to assess the complications, joint-specific function, health-related quality of life, and radiological signs of loosening of the acetabular component. Methods A single-centre, prospective cohort study of 125 implants will be undertaken. Patients undergoing hybrid THA at the study centre will be recruited. Inclusion criteria are patients suitable for the use of the uncemented acetabular component, aged 18 to 75 years, willing and able to comply with the study protocol, and provide informed consent. Exclusion criteria includes patients not meeting study inclusion criteria, inadequate bone stock to support fixation of the prosthesis, a BMI > 40 kg/m 2 , or THA performed for pain relief in those with severely restricted mobility. Results Implant survival, complications, functional outcomes and radiological assessment up to ten years following index THA (one, two, five, seven, and ten years) will be performed. Functional assessment will include the Oxford Hip Score, Forgotten Joint Score, 12-Item Short Form Health Survey, EuroQol five-dimension health questionnaire, and pain and patient satisfaction. Radiological assessment with assess for acetabula lucent lines, lysis, and loosening according to DeLee and Charnley zones. Conclusion This study is part of a stepwise introduction of a new device to orthopaedic practice, and careful monitoring of implants should be carried out as part of the Beyond Compliance principles. The results of this study will provide functional, radiological, and survival data to either support the ongoing use of the HA acetabulum or highlight potential limitations of this new implant before wide adoption. Cite this article: Bone Jt Open 2023;4(10):782–790.

Background Robotic-assisted unicompartmental knee arthroplasty (UKA) improves implant accuracy, however whether this translates to patient function is less clear. Various outcomes have been reported but muscle recovery has not been previously investigated. Objective To explore sequential change in lower limb muscle strength following robotic-assisted UKA with isokinetic dynamometry. Results 12 participants undergoing rUKA for medial compartment osteoarthritis were assessed pre-operatively, and at 6- and 12-weeks post-operatively. Maximal muscle strength changed over time in both quadriceps (p = 0.006) and hamstrings (p = 0.018) muscle groups. Quadriceps strength reduced from 88.52(39.86)Nm to 74.47(27.58)Nm by 6-weeks (p = 0.026), and then recovered to 90.41(38.76)Nm by 12-weeks (p = 0.018). Hamstring strength reduced from 62.45(23.18)Nm to 54.12(20.49)Nm by 6-weeks (p = 0.016), and then recovered to 55.07(17.99)Nm by 12-weeks (p = 0.028). By 12-weeks quadriceps strength was 70% and hamstrings 83% of the values achieved in the un-operated limb. Substantial improvement was seen in all other measures over time, with sequential positive change in Timed-up-and-go test (p = 0.015), 10 m walk test (p = 0.021), range of knee flexion (p = 0.016) and PROMs (p < 0.025).

Aims: The primary aim of this study is to assess the survival of the uncemented hydroxyapatite (HA) coated Trident II acetabular component as part of a hybrid total hip arthroplasty (THA) using a cemented Exeter stem. The secondary aims are to assess the complications, joint-specific function, health-related quality of life, and radiological signs of loosening of the acetabular component. Methods: A single-centre, prospective cohort study of 125 implants will be undertaken. Patients undergoing hybrid THA at the study centre will be recruited. Inclusion criteria are patients suitable for the use of the uncemented acetabular component, aged 18 to 75 years, willing and able to comply with the study protocol, and provide informed consent. Exclusion criteria includes patients not meeting study inclusion criteria, inadequate bone stock to support fixation of the prosthesis, a BMI > 40 kg/m2, or THA performed for pain relief in those with severely restricted mobility. Results: Implant survival, complications, functional outcomes and radiological assessment up to ten years following index THA (one, two, five, seven, and ten years) will be performed. Functional assessment will include the Oxford Hip Score, Forgotten Joint Score, 12-Item Short Form Health Survey, EuroQol five-dimension health questionnaire, and pain and patient satisfaction. Radiological assessment with assess for acetabula lucent lines, lysis, and loosening according to DeLee and Charnley zones. Conclusion: This study is part of a stepwise introduction of a new device to orthopaedic practice, and careful monitoring of implants should be carried out as part of the Beyond Compliance principles. The results of this study will provide functional, radiological, and survival data to either support the ongoing use of the HA acetabulum or highlight potential limitations of this new implant before wide adoption. Cite this article: Bone Jt Open 2023;4(10):782–790.

Purpose:The aim was to assess the cost-effectiveness of robotic arm-assisted total hip arthroplasty (rTHA) compared with manual total hip arthroplasty (mTHA) and to assess the influence of annual volume on the relative cost-effectiveness of rTHA.Methods:A database of both rTHA (n = 48 performed in a private centre) and mTHA (n = 512 performed in the National Health Service) was used. Patient demographics, preoperative Oxford hip score, forgotten joint score, EuroQol 5-dimensional 3-level (EQ-5D), and postoperative EQ-5D were recorded. Two models for incremental cost-effectiveness ratios using cost per quality-adjusted life year (QALY) for rTHA were calculated based on a unit performing 100 rTHAs per year: 10-year follow-up and a lifetime time horizon (remaining life expectancy of a 69-year-old patient).Results:When adjusting for confounding factors, rTHA was independently associated with a 0.091 (p=0.029) greater improvement in the EQ-5D compared to mTHA. This resulted in a 10-year time horizon cost per QALY for rTHA of £1,910 relative to mTHA, which increased to £2,349 per QALY when discounted (5%/year). When using the 10-year time horizon cost per QALY was approximately £3,000 for a centre undertaking 50 rTHAs per year and decreased to £1,000 for centre undertaking 200 rTHAs per year. Using a lifetime horizon, the incremental unadjusted cost per QALY gained was £980 and £1432 when discounted (5%/year) for rTHA compared with mTHA.Conclusions:Despite the increased cost associated with rTHA, it was a cost-effective intervention relative to mTHA due to the associated greater health-related quality of health gain, according to the EQ-5D outcome measure.

A correction to this paper has been published: https://doi.org/10.1007/s00167-021-06522-x

Aims The primary aim of the study was to compare the knee-specific functional outcome of robotic unicompartmental knee arthroplasty (rUKA) with manual total knee arthroplasty (mTKA) for the management of isolated medial compartment osteoarthritis. Secondary aims were to compare length of hospital stay, general health improvement, and satisfaction between rUKA and mTKA. Methods A powered (1:3 ratio) cohort study was performed. A total of 30 patients undergoing rUKA were propensity score matched to 90 patients undergoing mTKA for isolated medial compartment arthritis. Patients were matched for age, sex, body mass index (BMI), and preoperative function. The Oxford Knee Score (OKS) and EuroQol five-dimension questionnaire (EQ-5D) were collected preoperatively and six months postoperatively. The Forgotten Joint Score (FJS) and patient satisfaction were collected six months postoperatively. Length of hospital stay was also recorded. Results There were no significant differences in the preoperative demographics (p >= 0.150) or function (p >= 0.230) between the groups. The six-month OKS was significantly greater in the rUKA group when compared with the mTKA group (difference 7.7, p < 0.001). There was also a greater six-month postoperative EQ-5D (difference 0.148, p = 0.002) and FJS (difference 24.2, p < 0.001) for the rUKA when compared to the mTKA. No patient was dissatisfied in the rUKA group and five (6%) were dissatisfied in the mTKA, but this was not significant (p = 0.210). Length of stay was significantly (p < 0.001) shorter in the rUKA group (median two days, interquartile range (IQR) 1 to 3) compared to the mTKA (median four days, IQR 3 to 5). Conclusion Patients with isolated medial compartment arthritis had a greater knee-specific functional outcome and generic health with a shorter length of hospital stay after rUKA when compared to mTKA.

Patient function is poorly characterised following revision TKA. Modern semi-constrained implants are suggested to offer high levels of function, however, data is lacking to justify this claim. 52 consecutive aseptic revision TKA procedures performed at a single centre were prospectively evaluated; all were revision of a primary implant to a Triathlon total stabiliser prosthesis. Patients were assessed pre-operatively and at 6, 26, 52 and 104 weeks post-op. Outcome assessments were the Oxford Knee Score (OKS), range of motion, pain rating scale and timed functional assessment battery. Analysis was by repeated measures ANOVA with post-hoc Tukey HSD 95% simultaneous confidence intervals as pairwise comparison. Secondary analysis compared the results of this revision cohort to previously reported primary TKA data, performed by the same surgeons, with identical outcome assessments at equivalent time points. Mean age was 73.23 (SD 10.41) years, 57% were male. Mean time since index surgery was 9.03 (SD 5.6) years. 3 patients were lost to follow-up. All outcome parameters improved significantly over time (p No difference was seen between primary and revision cohorts in OKS (p = 0.2) or pain scores (p=0.19). Range of motion and functional performance was different between groups over the 2 year period (p=0.03), however this was due to differing pre-operative scores, post-hoc analysis showed no difference between groups at any post-operative time point. Patients undergoing aseptic revision TKA with semi-constrained implants made substantial improvements in OKS, pain scores, knee flexion, and timed functional performance, with the outcomes achieved comparable to those of primary TKA. High levels of function can be achieved following revision knee arthroplasty, which may be important considering the changing need for, and demographics of, revision surgery.

Background: The aim of this study is to investigate differences in implant requirement, outcomes, and re-revision when total knee arthroplasty (TKA) was performed following unicompartmental knee arthroplasties (UKAs) with metal-backed (MB) compared to all-polyethylene (AP) tibial components. Methods: Retrospective study of 60 UKAs converted to 60 TKAs at mean 7.3 years (0.1 to 17) after implantation in 55 patients (mean age, 64 [49-83]; 44% male): 44 MB and 16 AP. TKA implant requirement was investigated in addition to mode of failure, Oxford Knee Score, and TKA survival at mean 5.4 years (0.5 to 17). Results: Progression of osteoarthritis was the commonest mode of failure in MB UKAs (P = .03) and unexplained pain in AP (P = .011) where revisions were performed earlier (4.8 +/- 3.2 vs 8.2 +/- 4.5, P = .012). In 56 of 60 (93%) cases, unconstrained TKA implants were used. The use of standard cruciate-retaining TKAs without augments or stems was less likely following MB UKA compared to AP (12 of 38 [32%] vs 10/14 [71%], P = .013). Specifically MB UKA implants were associated with more tibial stem use (P = .04) and more use of cruciate-substituting polyethylene (P = .05). There was no difference in the use of constrained implants. Multivariate analysis showed tibial resection depth to predict stem requirement. Seven were re-revised giving 7-year TKA survival: from MB UKA 70.3 (95% CI, 47.0 to 93.6) and from AP UKA 87.5 (95% CI, 64.6 to 100; P = .191). Conclusion: MB UKA implants increase the chances of a complex revision requiring tibial stems and cruciate substitution but reduce the chances of early revision compared to AP UKA which often fail early with pain. (c) 2018 Elsevier Inc. All rights reserved.

General rights Copyright for the publications made accessible via the Edinburgh Research Explorer is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy The University of Edinburgh has made every reasonable effort to ensure that Edinburgh Research Explorer content complies with UK legislation. If you believe that the public display of this file breaches copyright please contact openaccess@ed.ac.uk providing details, and we will remove access to the work immediately and investigate your claim. Accepted Manuscript Aseptic revision knee arthroplasty with total stabilizer prostheses achieves similar functional outcomes to primary total knee arthroplasty at 2 years: a longitudinal cohort study knee arthroplasty with total stabilizer prostheses achieves similar functional outcomes to primary total knee arthroplasty at 2 years: a longitudinal cohort study, This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Aseptic revision knee arthroplasty with total stabilizer prostheses achieves similar functional 1 outcomes to primary total knee arthroplasty at 2 years: a longitudinal cohort study 2 3 4 ABSTRACT 5 6 Background 7 Patient function is poorly characterised following revision total knee arthroplasty, though is 8 generally accepted to be inferior to that following primary procedures. 9 10 Methods 11 53 consecutive aseptic revisions to total stabilizer devices were prospectively evaluated, pre-12 operatively and at 6, 26, 52 and 104 weeks post-operatively, using the Oxford Knee Score (OKS), 13 range of motion, pain rating scale, and timed functional performance battery. Data was assessed 14 longitudinally and in comparison to primary TKA data with identical outcome assessments at 15 equivalent time points. No difference was seen between primary and revision cohorts in 22 OKS or pain scores (ANOVA, p=0.2 and 0.19). Knee flexion and timed performance assessment were 23 different between primary and revision groups (ANOVA, p=0.03 and p= 0.02) however this was due 24 to differing pre-operative values. The revision cohort achieved the same post-operative scores as …

BACKGROUND:Patient function is poorly characterized following revision total knee arthroplasty (TKA), although is generally accepted to be inferior to that following primary procedures. METHODS:Fifty-three consecutive aseptic revisions to total stabilizer devices were prospectively evaluated, preoperatively and at 6, 26, 52, and 104 weeks postoperatively, using the Oxford Knee Score (OKS), range of motion, pain rating scale, and timed functional performance battery. Data were assessed longitudinally and in comparison to primary TKA data with identical outcome assessments at equivalent time points. RESULTS:Mean outcome changes were: 13 point increase in the OKS (from 17.5 [standard deviation-SD 7.4]-32.4 [SD 7.9] points); 21 degree improvement in the knee flexion (80.6 [SD 20.5]-101.5 [SD 13.2] degrees); 60% reduction in the pain report (7.7 [SD 2.3]-1.3 [SD 0.4] points); and 15 second improvement in the timed performance assessment (47.2 [SD 19.1]-32.0 [SD 7.0] seconds; P < .001). No difference was seen between primary and revision cohorts in OKS or pain scores (analysis of variance, P = .2 and .19). Knee flexion and timed performance assessment were different between primary and revision groups (analysis of variance, P = .03 and P = .02); however, this was due to differing preoperative values. The revision cohort achieved the same postoperative scores as the primary cohort at all postoperative time points. CONCLUSION:Patients undergoing revision TKA for aseptic failure with total stabilizer implants made substantial improvements in the initial 2 years following surgery in both patient-reported and directly assessed function, comparable with that achieved following primary knee arthroplasty.

Bleeding-related wound complications cause significant morbidity in lower limb arthroplasty surgery. Patients who require therapeutic anticoagulation in the perioperative period are potentially at higher risk for these complications. This is a retrospective case-control study reviewing all primary total hip arthroplasties performed in a single center during a 5-year period and comparing outcomes of the patients on warfarin with a double-matched control group of patients not on warfarin. The warfarin group had a significantly higher risk of deep joint infection (9% vs 2.2%), hematoma/wound ooze (28% vs 4%), and superficial infection (13.5% vs 2.2%). Managing patients undergoing total hip arthroplasty with therapeutic anticoagulation is a balance between the risk of thromboembolic disease and bleeding-related complications. Improved understanding of this risk will better allow patients to make an informed decision regarding their elective arthroplasty surgery.

We describe a scaling method for templating digital radiographs using conventional acetate templates independent of template magnification without the need for a calibration marker. The mean magnification factor for the radiology department was determined (119.8%; range, 117%-123.4%). This fixed magnification factor was used to scale the radiographs by the method described. Thirty-two femoral heads on postoperative total hip arthroplasty radiographs were then measured and compared with the actual size. The mean absolute accuracy was within 0.5% of actual head size (range, 0%-3%) with a mean absolute difference of 0.16 mm (range, 0-1 mm; SD, 0.26 mm). Intraclass correlation coefficient showed excellent reliability for both interobserver and intraobserver measurements with intraclass correlation coefficient scores of 0.993 (95% CI, 0.988-0.996) for interobserver measurements and intraobserver measurements ranging between 0.990 and 0.993 (95% CI, 0.980-0.997).