All-polyethylene tibia components have the same functional outcomes and survival, and are more cost-effective than metal-backed components in patients 70 years and older undergoing total knee arthroplasty : propensity match study with a minimum five-year follow-up.

AIMS: The tibial component of total knee arthroplasty can either be an all-polyethylene (AP) implant or a metal-backed (MB) implant. This study aims to compare the five-year functional outcomes of AP tibial components to MB components in patients aged over 70 years. Secondary aims are to compare quality of life, implant survivorship, and cost-effectiveness. METHODS: A group of 130 patients who had received an AP tibial component were matched for demographic factors of age, BMI, American Society of Anesthesiologists (ASA) grade, sex, and preoperative Knee Society Score (KSS) to create a comparison group of 130 patients who received a MB tibial component. Functional outcome was assessed prospectively by KSS, quality of life by 12-Item Short-Form Health Survey questionnaire (SF-12), and range of motion (ROM), and implant survivorships were compared. The SF six-dimension (6D) was used to calculate the incremental cost effectiveness ratio (ICER) for AP compared to MB tibial components using quality-adjusted life year methodology. RESULTS: The AP group had a mean KSS-Knee of 83.4 (standard deviation (SD) 19.2) and the MB group a mean of 84.9 (SD 18.2; p = 0.631), while mean KSS-Function was 75.4 (SD 15.3) and 73.2 (SD 16.2 p = 0.472), respectively. The mental (44.3 vs 45.1; p = 0.464) and physical (44.8 vs 44.9; p = 0.893) dimensions of the SF-12 and ROM (97.9° vs 99.7°; p = 0.444) were not different between the groups. Implant survivorship at five years were 99.2% and 97.7% (p = 0.321). The AP group had a greater SF-6D gain of 0.145 compared to the MB group, with an associated cost saving of £406, which resulted in a negative ICER of -£406/0.145 = -£2,800. Therefore, the AP tibial component was dominant, being a more effective and less expensive intervention. CONCLUSION: There were no differences in functional outcomes or survivorship at five years between AP and MB tibial components in patients aged 70 years and older, however the AP component was shown to be more cost-effective. In the UK, only 1.4% of all total knee arthroplasties use an AP component; even a modest increase in usage nationally could lead to significant financial savings.Cite this article: Bone Jt Open 2022;3(12):969-976.

The '2-in-1' stage: indications, technique & results.

Prosthetic joint infections remain an ongoing challenge for orthopaedic surgeons with an interest in knee arthroplasty, which relates to their often difficult diagnoses, need for multiple surgeries, increased technical and financial requirements. Peri-prosthetic joint infection is devastating complication for the patient and with the current literature unable to either demonstrate superiority of one or two stage revision then we should continue to assess on a case by case basis. The use of a '2 in 1' single-stage approach has been recently been promoted as a form of single stage revision for infection on account of the potential for reduction in risks, costs, and complications. Where it is safe to do so, a single stage procedure can avoid several of the drawbacks which may occur with a formal two stage approach. Particularly, it can reduce the risk of post-operative stiffness and arthrofibrosis which can be associated with two stage surgery. Use of a single stage may be more cost effective, by saving the patient having to undergo a second major procedure. This article reviews the indications for its use, technique and results. The use of '2-in-1' single-stage revision can be considered as an effective option for treating infection following TKR and cases with associated bone loss.

The effect of hospital case volume on re-revision following revision total knee arthroplasty.

AIMS: The aim of this study was to measure the effect of hospital case volume on the survival of revision total knee arthroplasty (RTKA). METHODS: This is a retrospective analysis of Scottish Arthroplasty Project data, a nationwide audit which prospectively collects data on all arthroplasty procedures performed in Scotland. The primary outcome was RTKA survival at ten years. The primary explanatory variable was the effect of hospital case volume per year on RTKA survival. Kaplan-Meier survival curves were plotted with 95% confidence intervals (CIs) to determine the lifespan of RTKA. Multivariate Cox proportional hazards were used to estimate relative revision risks over time. Hazard ratios (HRs) were reported with 95% CI, and p-value < 0.05 was considered statistically significant. RESULTS: From 1998 to 2019, 8,301 patients (8,894 knees) underwent RTKA surgery in Scotland (median age at RTKA 70 years (interquartile range (IQR) 63 to 76); median follow-up 6.2 years (IQR 3.0 to 10.2). In all, 4,764 (53.6%) were female, and 781 (8.8%) were treated for infection. Of these 8,894 knees, 957 (10.8%) underwent a second revision procedure. Male sex, younger age at index revision, and positive infection status were associated with need for re-revision. The ten-year survival estimate for RTKA was 87.3% (95% CI 86.5 to 88.1). Adjusting for sex, age, surgeon volume, and indication for revision, high hospital case volume was significantly associated with lower risk of re-revision (HR 0.78 (95% CI 0.64 to 0.94, p < 0.001)). The risk of re-revision steadily declined in centres performing > 20 cases per year; risk reduction was 16% with > 20 cases; 22% with > 30 cases; and 28% with > 40 cases. The lowest level of risk was associated with the highest volume centres. CONCLUSION: The majority of RTKA in Scotland survive up to ten years. Increasing yearly hospital case volume above 20 cases is independently associated with a significant risk reduction of re-revision. Development of high-volume tertiary centres may lead to an improvement in the overall survival of RTKA. Cite this article: Bone Joint J 2021;103-B(4):602-609.

Revision total knee arthroplasty versus primary total knee arthroplasty: a matched cohort study.

INTRODUCTION: The primary aim of this study was to describe a baseline comparison of early knee-specific functional outcomes following revision total knee arthroplasty (TKA) using metaphyseal sleeves with a matched cohort of patients undergoing primary TKA. The secondary aim was to compare incidence of complications and length of stay (LOS) between the two groups. METHODS: Patients undergoing revision TKA for all diagnoses between 2009 and 2016 had patient-reported outcome measures (PROMs) collected prospectively. PROMs consisted of the American Knee Society Score (AKSS) and Short-Form 12 (SF-12). The study cohort was identified retrospectively and demographics were collected. The cohort was matched to a control group of patients undergoing primary TKA. RESULTS: Overall, 72 patients underwent revision TKA and were matched with 72 primary TKAs with a mean follow-up of 57 months (standard deviation (SD) 20 months). The only significant difference in postoperative PROMs was a worse AKSS pain score in the revision group (36 vs 44, p = 0.002); however, these patients still produced an improvement in the pain score. There was no significant difference in improvement of AKSS or SF-12 between the two groups. LOS (9.3 days vs 4.6 days) and operation time (1 hour 56 minutes vs 1 hour 7 minutes) were significantly higher in the revision group (p < 0.001). Patients undergoing revision were significantly more likely to require intraoperative lateral release and postoperative urinary catheterisation (p < 0.001). CONCLUSION: This matched-cohort study provides results of revision TKA using modern techniques and implants and outlines what results patients can expect to achieve using primary TKA as a control. This should be useful to clinicians counselling patients for revision TKA.

Range of movement correlates with the Oxford knee score after total knee replacement: A prediction model and validation.

BACKGROUND: Patient reported outcome measures are widely used in the evaluation of outcomes after Total Knee Replacement (TKR) in joint registries and large studies. The aim of this study was to assess the relationship between the Oxford knee score (OKS) and range of motion (ROM) after TKR, and to construct and validate prediction models of ROM from the measured OKS. METHODS: Eight hundred sixty patients reviewed five years postoperatively and 273 patients reviewed nine to 10 years postoperatively completed an OKS. Of these, 808 (94%) and 226 (83%) patients, respectively, had a complete dataset (knee extension and ROM) and formed the study cohort. RESULTS: Regression analysis demonstrated a significant correlation between the OKS and ROM (r=0.38, p<0.001) after adjusting for other confounding variables (age, sex, body mass index, and knee extension). A prediction model was constructed and validated using a second cohort of 226 patients at nine to 10 years after their TKR. Intraclass correlation demonstrated good reliability (r=0.60, 95% CI 0.47 to 0.69) between predicted and actual measured ROM for this group. However, when the OKS is used in isolation the reliability of the predicted ROM is diminished (intraclass correlation r=0.41, 95% CI 0.24 to 0.55). CONCLUSIONS: The OKS is an independent predictor of ROM after TKR. It is also possible to predict ROM from the OKS, but the reliability of this is improved when other independent predictors such as age, gender, body mass index (BMI) and degree of knee extension are also acknowledged.

Radial head and neck fractures: functional results and predictors of outcome.

BACKGROUND: The purpose of this study was to determine the functional outcomes and predictive factors of radial head and neck fractures. METHODS: Over an 18-month period, we performed a prospective study of 237 consecutive patients with a radiographically confirmed proximal radial fracture (156 radial head and 81 radial neck). Follow-up was carried out over a 1-year period using clinical and radiologic assessment, including the Mayo Elbow Score (MES). Multivariate regression analysis was used to determine significant predictors of outcome according to the MES. RESULTS: Of the 237 patients enrolled in the study, 201 (84.8%) attended for review, with a mean age of 44 years (range, 16-83 years; standard deviation, 17.3). One hundred eighty-seven (93%) patients achieved excellent or good MESs. The mean MES for Mason type-I (n = 103) and type-II (n = 82) fractures was excellent, with only two patients undergoing surgical intervention. For Mason type-III (n = 11) and type-IV (n = 5) fractures, the flexion arc, forearm rotation arc, and MES in the nonoperatively treated patients were not significantly different (all p ≥ 0.05) from those managed operatively. Regression analysis revealed that increasing age, increasing fracture complexity according to the AO-OTA classification, increasing radiographic comminution, and operative treatment choice were independently significant predictors of a poorer outcome (all p < 0.05). CONCLUSIONS: A majority of radial head and neck fractures can be treated nonoperatively, achieving excellent or good results. Age, fracture classification, radiographic comminution, and treatment choice are important factors that determine recovery.