Progression of osteoarthritis and reoperation in unicompartmental knee arthroplasty: A comparison of national joint registries

Global mapping of institutional and hospital-based (Level II-IV) arthroplasty registries: a scoping review

PURPOSE

Four joint arthroplasty registries (JARs) levels exist based on the recorded data type. Level I JARs are national registries that record primary data. Hospital or institutional JARs (Level II-IV) document further data (patient-reported outcomes, demographic, radiographic). A worldwide list of Level II-IV JARs must be created to effectively assess and categorize these data.

METHODS

Our study is a systematic scoping review that followed the PRISMA guidelines and included 648 studies. Based on their publications, the study aimed to map the existing Level II-IV JARs worldwide. The secondary aim was to record their lifetime, publications' number and frequency and recognise differences with national JARs.

RESULTS

One hundred five Level II-IV JARs were identified. Forty-eight hospital-based, 45 institutional, and 12 regional JARs. Fifty JARs were found in America, 39 in Europe, nine in Asia, six in Oceania and one in Africa. They have published 485 cohorts, 91 case-series, 49 case-control, nine cross-sectional studies, eight registry protocols and six randomized trials. Most cohort studies were retrospective. Twenty-three per cent of papers studied patient-reported outcomes, 21.45% surgical complications, 13.73% postoperative clinical and 5.25% radiographic outcomes, and 11.88% were survival analyses. Forty-four JARs have published only one paper. Level I JARs primarily publish implant revision risk annual reports, while Level IV JARs collect comprehensive data to conduct retrospective cohort studies.

CONCLUSIONS

This is the first study mapping all Level II-IV JARs worldwide. Most JARs are found in Europe and America, reporting on retrospective cohorts, but only a few report on studies systematically.

Unicompartmental knee arthroplasties: does the type of tibial component selected influence implant survival?

INTRODUCTION

Few information has been published on the survival of unicompartmental knee arthroplasty (UKA) and fixed-bearing tibial components. The aim of this study is to analyze if UKA survival varies according to UKA model used and to analyze the possible risk factors for UKA revision.

MATERIALS AND METHODS

A retrospective study analyzing 301 UKAs (ACCURIS, all-polyethylene tibial component, 152; Triathlon PKR, metal-backed tibial component, 149) was performed. Demographic parameters as well as implant survival and cause of prosthetic revision were analyzed. The Kaplan-Meier survival analysis, the log-rank test and the Cox multiple regression were used for the analysis.

RESULTS

Average follow-up was 8.1 ± 3.08-years. Average age was 68.1 ± 8.6-years; 70.4% of subjects were women. The ACCURIS UKA group had a UKA revision rate higher compared to the Triathlon PKR group (16/152, 10.6% vs 5/149, 3.4%, respectively; p < 0.001). The main cause of prosthetic revision was aseptic loosening (5/21, 23.8%). All aseptic loosening cases and tibial component collapse were reported with the ACCURIS UKA group. Overall UKA survival was 98.01% (95% CI 95.62-99.1) at 1-year, 94.27% (95% CI 90.95-96.4) at 5-years and 92.38% (95% CI 88.48-94.99) at 10-years' follow-up. There were no differences in the Kaplan-Meier survival curves regarding operated side or affected tibiofemoral compartment (log-rank test = 0.614 and 0.763, respectively). However, Kaplan-Meier survival curve according to UKA model used was different (log-rank test = 0.033). The metal-backed component appeared to be a protector factor for UKA revision when adjusted for age, sex, operated side, and affected tibiofemoral compartment (Hazard Ratio 0.32, p = 0.031).

CONCLUSION

Fixed-bearing UKAs showed excellent mid- and long-term survival rates. Aseptic loosening is the main cause of implant failure. PKR group (metal-backed component) seem to be a protector factor to UKA revision when it was compared with ACCURIS UKA group (all-polyethylene tibial component).

Finite Element Analysis of the Effect of Femoral Prosthesis Varus and Valgus Angle Installation on the Lateral Compartment in Unicompartmental Knee Arthroplasty

BACKGROUND

This study used finite element analysis (FEA) to investigate the effect of varus and valgus angle on the lateral compartment in unicompartmental knee arthroplasty (UKA).

METHODS

One patient who underwent UKA was enrolled as the subject. Thirteen working conditions of the femoral prosthesis were simulated at varus and valgus angles of 0°, 2°, 4°, 6°, 8°, 10°, and 12°. A load of 1,000 N was applied downward along the mechanical axis of the femur, and the highest stress values on the surface of the polyethylene liner, cancellous bone under the tibial prosthesis, cartilage of femur lateral condyle, lateral meniscus, and tibial lateral plateau cartilage in each model were recorded. The six highest points were used to calculate the mean value.

RESULTS

The highest stress values on the surface of the polyethylene liner, cancellous bone under the tibial prosthesis, cartilage of femur lateral condyle, lateral meniscus, and tibial lateral plateau cartilage increased with an increase in the femoral prosthesis varus/valgus angle. As compared with the standard position of the femoral prosthesis, there was no significant difference in the surface stress values of the polyethylene liner, cancellous bone under the tibial prosthesis, cartilage of femur lateral condyle, lateral meniscus and tibial lateral plateau cartilage when the femoral prosthesis varus/valgus angle was less than 4° (p > 0.05). In addition, the stress magnitude on the polyethylene liner, cancellous bone under the tibial prosthesis, cartilage of femur lateral condyle, lateral meniscus, and tibial lateral plateau cartilage significantly increased when the femoral prosthesis varus/valgus angle was greater than 4° (p < 0.001).

CONCLUSIONS

The optimal femoral prosthesis varus/valgus angle in UKA was less than 4°.

The impact of preoperative MRI-detected lateral meniscal intra-substance signal abnormalities on mid-term functional outcomes following mobile-bearing unicompartmental knee arthroplasty

PURPOSE

There is a dilemma as to whether the presence of degenerative changes of lateral meniscus is a contraindication to medial unicompartmental knee arthroplasty (UKA). Therefore, the purpose of this study is to assess the influence of preoperative MRI-detected lateral meniscal intra-substance signal abnormalities on mid-term functional outcomes following mobile-bearing UKA.

METHODS

We performed a retrospective review of the record on a consecutive series of patients who have undergone mobile-bearing medial UKA from September 2020 to June 2023. The mean duration of follow-up was 2.34 years. All records were collected from case system. MRI assessment of lateral meniscus was performed with the use of the Stoller's classification system. Patients were categorized into two groups (grade 0 and ≥ grade 1). Patient-reported outcomes were assessed with the use of the American Knee Society functional Score (AKSS-F), American Knee Society Objective Score (AKSS-O), and Oxford Knee Score (OKS) preoperatively and at latest follow-up. Furthermore, range of motion (ROM) and hip-knee-ankle angle (HKA) were measured in preoperative and postoperative periods.

RESULTS

A total of 92 patients (101 knees) were included in our study. No differences in AKSS-F, AKSS-O, OKS, HKA, or ROM were found between those who showed normal or abnormal signal change of lateral meniscus preoperatively (P < 0.05). Furthermore, there were also no significant differences between two groups concerning AKSS-F, AKSS-O, OKS, HKA, or ROM at latest postoperative follow-up (P < 0.05). Age and duration of disease were independent predictors of low postoperative AKSS-F and AKSS-O (P < 0.05). Nevertheless, ROM was an independent predictor of high postoperative AKKS-O (P < 0.05). Age and female were independent predictors of high postoperative OKS (P < 0.05).

CONCLUSION

The presence of preoperative MRI-detected lateral meniscal degenerative changes did not affect mid-term functional outcomes in patients who underwent mobile-bearing medial UKA. On the basis of the results of the current study, we believe that the presence of degenerative changes of lateral meniscus is acceptable in mobile-bearing medial UKA.

Gremlin-1 promotes IL-1β-stimulated chondrocyte inflammation and extracellular matrix degradation via activation of the MAPK signaling pathway

The role and mechanism of Gremlin-1 in osteoarthritis (OA) were expected to be probed in this study. Firstly, an in vitro OA model was constructed by stimulating human chondrocyte cell line CHON-001 with IL-1β. Next, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) were utilized for assessing the effect of IL-1β with different concentrations (5, 10, and 20 ng/mL) on the activity and Gremlin-1 messenger RNA of CHON-001 cells, respectively. Besides, the influence of knocking down/over-expressing Gremlin-1 on the inflammatory factors (IL-6, TNF-α, IL-18 and PGE2), oxidative stress-related substances (malondialdehyde [MDA]; superoxide dismutase [SOD]; lactate dehydrogenase [LDH]), extracellular matrix (ECM) degradation-related proteins, and mitogen-activated protein kinase (MAPK) pathway proteins in IL-1β-stimulated CHON-001 cells were tested by enzyme-linked immunosorbent assay, related kits, qRT-PCR, and western blot, respectively. IL-1β inhibited CHON-001 cell proliferation and upregulated Gremlin-1 expression in a concentration-dependent manner. Overexpression of Gremlin-1 increased the IL-6, TNF-α, IL-18, PGE2, and MDA levels, enhanced the LDH activity, and decreased the SOD activity in IL-1β-induced CHON-001 cells; while the effect of Gremlin-1 knockdown on the above factors was in contrast with that of the overexpression. Furthermore, overexpression of Gremlin-1 upregulated protein expression of matrix metalloproteinase (MMP)-3, MMP-13, and ADAMTS4 while downregulated protein expression of collagen III, aggrecan, and SOX-9 in IL-1β-stimulated CHON-001 cells. Besides, overexpression of Gremlin-1 increased the p-p38/p38 value while decreased the p-JNK/JNK value in L-1β-stimulated CHON-001 cells; however, knockdown of Gremlin-1 reversed the above results. Gremlin-1 may promote IL-1β-stimulated CHON-001 cell inflammation and ECM degradation by activating the MAPK signaling pathway.

Unicompartmental knee arthroplasty: A French multicenteric retrospective descriptive study from 2009 to 2019 with projections to 2050

INTRODUCTION

Unicompartmental knee arthroplasty (UKA) is a reliable and reproducible procedure. While some surgeons have incorporated it into their therapeutic armamentarium, others do not use it routinely, leading to a large disparity in practice. The objective of this study was to investigate in France the epidemiology of UKA from 2009 to 2019 to identify: (1) the evolution of growth trends by sex and age, (2) the evolution of the state of comorbidity of patients during the operation, (3) the evolution of trends according to the regions, (4) the projection best suited to the observations at 2050.

HYPOTHESIS

Our hypothesis was that in France, an increase would be observed over the period studied, differing according to the characteristics of the population.

MATERIALS AND METHOD

The study was conducted in France over the 2009-2019 period for each gender and age group. The data was taken from the NHDS (National Health Data System) database, which includes all the procedures carried out in France. Based on the collection of procedures performed, the incidence rates (per 100,000 inhabitants) and their evolution were deduced, as well as the indirect assessment of the patient's comorbidity status. Using linear, Poisson, and logistic projection models, incidence rates were projected to the years 2030, 2040, and 2050.

RESULTS

Between 2009 and 2019, the incidence rate of UKA increased sharply (from 12.76 to 19.57; +53%), the growth was different in men (from 10.78 to 20.34; +89%) and women (from 14.61 to 18.85; +29%). The male/female sex ratio increased from 0.69 in 2009 to 1.0 in 2019. The increase was greatest among men under 65 (from 4.9 to 9.9; +100%) and lowest among women over 75 (from 41.2 to 40.5; -2%). Over the period studied, the proportion of patients with mild comorbidities (HPG1) increased (from 71.7% to 81.1%) at the expense of the other classes with more severe comorbidities. This dynamic was observed for all age groups: 0-64 years (from 83.3% to 90%), 65-74 years (from 81.4% to 88.4%), 75 years and over (38 .2% to 52.6%) regardless of sex. There was a strong disparity between the regions with a change in the incidence rate ranging from -22% (from 29.8 to 23.1) for Corsica to +251% (from 13.9 to 48.7) for Brittany. The proposed projection models suggested an increase in the incidence rate of +18% in logistic regression, +103% in linear regression by 2050.

DISCUSSION

Our study showed strong growth in the number of UKAs in France over the period studied, being highest in young men. The proportion of patients with fewer comorbidities increased for all age groups. A disparity in inter-regional practice was identified, with indications that remain ambiguous and differ according to the practitioner. We can expect continued growth in the years to come, adding to the care burden.

LEVEL OF EVIDENCE

IV; Descriptive epidemiological study.

Combined treatment with medial unicompartmental knee arthroplasty and anterior cruciate ligament reconstruction is effective on long-term follow-up

PURPOSE

The purpose of the present study was to evaluate the long-term outcome of combined medial unicompartmental knee arthroplasty (UKA) and anterior cruciate ligament reconstruction (ACLR). The authors hypothesized that the combined procedure leads to good long-term outcome in patients with isolated medial knee osteoarthritis (OA) and anterior cruciate ligament (ACL) deficiency.

METHODS

Twenty-three patients with ACL deficiency and concomitant medial knee OA were treated from 2008 to 2016 with a combined UKA (Oxford Partial Knee) and ACLR using a hamstring tendon autograft. The follow-up assessment included VAS pain score, Lysholm score, Oxford Knee Score (OKS), American Knee Society scores (AKSS), International Knee Documentation Committee (IKDC 2000), Tegner and UCLA activity scores. Instrumented laxity test was done using the KT-1000 arthrometer. Survivorship analysis was performed using the Kaplan-Meier method. Implant loosening and disease progression was assessed by conventional radiography.

RESULTS

Average follow-up duration was 10 years (6-14.5). VAS, Lysholm, Tegner and UCLA scores improved significantly. OKS, AKSS and IKDC 2000 showed excellent results on follow-up. Implant survivorship was 91.4% at 14.5 years. There were 2 revisions with conversion to total knee arthroplasty at 6 and 12 years postoperatively due to trauma and disease progression, respectively. There were no radiological or clinical signs of instability or disease progression in any of the remaining knees. The side-to-side difference using the KT-1000 arthrometer was insignificant.

CONCLUSIONS

UKA combined with ACLR is an effective therapeutic option with good outcome and return to sport rate on the long-term.

LEVEL OF EVIDENCE

IV.

Safety and Efficacy of Single Condylar Knee Prosthesis When Treating Knee Single Compartment Osteoarthritis: A Prospective, Case-Randomized Controlled Study

Objective. The aim of this study is to explore the safety and efficacy of single condylar knee prosthesis when treating knee single compartment osteoarthritis by measuring the decrease of hemoglobin, total postoperative blood loss, maximum reduction of HCT, and knee joint activity. Methods. A total of 80 patients with knee joint single compartment osteoarthritis treated in our hospital from January 2020 to December 2021 were studied. They were randomly assigned to a study group (n = 40) and a control group (n = 40). The study group was treated with total knee prosthesis, while the control group was treated with simple knee prosthesis. The decrease rate of hemoglobin, the amount of bleeding, and the maximum decrease of hematocrit were compared after treatment. The range of motion of knee joint was evaluated by the Fugl-Meyer motor function scale (FM-B) and Berg balance scale (BBS). Results. The decrease of hemoglobin in the study group at 24 hours, 36 hours, and 48 hours after treatment was remarkably lower ( $P$  < 0.05). The total blood loss and the maximum reduction of hematocrit(HCT) in the study group were lower ( $P$  < 0.05). The range of motion (ROM) of the knee joint in the study group at 6 and 12 months after treatment was remarkably higher than that before treatment and remarkably higher compared to the control group ( $P$  < 0.05). The FM-B scale and BBS scale of the studied cohort at 6 and 12 months after treatment were remarkably higher than those before treatment and were remarkably higher compared to the control’s ( $P$  < 0.05). Conclusion. The unicondylar knee prosthesis is safer and more effective in the treatment of noncompartmental osteoarthritis of the knee, facilitating less trauma and perioperative blood loss and enhancing the patient’s motion and balance.

LIM mineralization protein-1 inhibits IL-1β-induced human chondrocytes injury by altering the NF-κB and MAPK/JNK pathways

Osteoarthritis (OA) is a common degenerative disease that is associated with the degradation of articular cartilage. Accumulating evidence has confirmed that LIM mineralization protein-1 (LMP-1) is an important agent of bone formation and has been shown to be osteoinductive in various types of disease. However, the underlying mechanisms of LMP-1 in the pathogenesis of OA remain unknown. The present study aimed to evaluate the role and potential mechanism of LMP-1 in IL-1β-stimulated OA chondrocytes. CHON-001 cells were transfected with pcDNA3.1-LMP-1, pcDNA3.1, negative control-small interfering (si)RNA or LMP-1 siRNA for 24 h and then induced by IL-1β for 12 h to establish an OA model in vitro. Cell viability, apoptosis and inflammatory cytokine (IL-6, IL-8 and TNF-α) release were assessed using MTT assay, flow cytometry and ELISA, respectively. The expression levels of LMP-1, cleaved-caspase 3, phosphorylated (p)-p65, p65, p-JNK and JNK were analyzed using reverse transcription-quantitative PCR and western blotting. Overexpression of LMP-1 notably alleviated the IL-1β-induced inflammatory response in CHON-001 cells, as shown by increased cell viability, decreased apoptosis, suppressed expression of cleaved-caspase 3 and a decreased cleaved-caspase 3/caspase 3 ratio. Moreover, IL-1β-induced secretion of IL-6, IL-8 and TNF-α in CHON-001 cells; this was reversed by pcDNA3.1-LMP-1. However, knocking down LMP-1 expression exert opposite effects on the IL-1β-induced inflammatory response in CHON-001 cells, as evidenced by the decreased cell viability, increased apoptosis, enhanced expression of cleaved-caspase 3 and cleaved-caspase 3/caspase 3 ratio and enhanced secretion of IL-6, IL-8 and TNF-α observed. The present data demonstrated that LMP-1 siRNA notably inhibited LMP-1 expression, suppressed cell viability, promoted apoptosis and enhanced cleaved-caspase 3 expression and cleaved-caspase 3/caspase 3 ratio. In addition, LMP-1 siRNA promoted the release of inflammatory factors in CHON-001 cells. It was also found that pcDNA3.1-LMP-1 inhibited p-p65 and p-JNK expression, as well as decreasing the p-p65/p65 and p-JNK/JNK ratio. Nevertheless, there was no significant difference in the mRNA expression levels of p65 and JNK between the groups. Taken together, these findings indicated that overexpression of LMP-1 alleviated IL-1β-induced chondrocytes injury by regulating the NF-κB and MAPK/JNK pathways, suggesting that LMP-1 may be a valuable therapeutic agent for OA treatment.

Treatment recommendations for chronic knee osteoarthritis

Primary osteoarthritis (OA) hinders an aging global population as one of the leading causes of years-lost-to-disability (YLD). OA in most patients is considered to be an overuse injury that results in degenerative inflammation of the joints with the associated formation of bony outgrowths. Due to the escalating nature of this chronic pain disease, treatment management for OA can initially begin with a more conservative approach. It can eventually lead to more invasive surgical procedures. At present, the standard of care remains initial conservative management with lifestyle changes, including weight loss with concurrent anti-inflammatory regimens. Injections are frequently used for the escalation of care, but a significant number of patients ultimately resort to total knee arthroplasty. This review will focus specifically on knee OA, providing a brief overview of risk factors and early management and in-depth exploration of the invasive interventions that can offer symptomatic relief and return of function.