Knee Joint Distraction Compared to Total Knee Arthroplasty for Treatment of End Stage Osteoarthritis: Simulating Long-Term Outcomes and Cost-Effectiveness

Patient with knee osteoarthritis demonstrates improved knee adduction moment after knee joint distraction: a case report

In this article we report a case of a 53-year-old patient diagnosed with end-stage osteoarthritis (OA) of the knee. The patient underwent treatment with knee joint distraction (KJD) with the aim to postpone total knee arthroplasty and prevent potential revision surgery. To assess the effect of KJD, a 3D gait analysis was performed preoperative and one year postoperative. In this patient, preoperative 3D gait analysis revealed an increased knee adduction moment (KAM) compared to healthy levels. Postoperative the KAM decreased, approaching healthy levels, suggesting potential improvements in disease status or in gait. Consequently, further investigation into the effectiveness of Knee Joint Distraction (KJD) as a treatment option for relatively young patients with knee OA is warranted. Gait analysis has emerged as an effective tool for assessing treatment outcomes of innovative treatment such as KJD at the individual level.

New concept of orthosis treatment for knee osteoarthritis: Clinical and radiological outcomes

BACKGROUND

Given the increasing numbers of young patients with knee osteoarthritis there is a need for treatments that can postpone a joint prosthesis (total knee replacement).

OBJECTIVE

As an alternative to the effective yet invasive knee joint distraction procedure, a knee orthosis was developed aiming to unload the affected knee and improving synovial fluid flow. The aim of this study was to examine the effectiveness of using a load-reducing orthosis for two months on functioning, pain, and disease progression (e.g. amount of damaged cartilage) in patients with symptomatic osteoarthritis of the knee for at least one year.

METHODS

This is an interventional single-center pilot study. Ten patients with symptomatic osteoarthritis of one knee (5 males/5 females; median age 57; age range 42-59) used a custom-made orthosis for 60 days during daily life activities that involved knee loading (e.g. standing, walking, but not during stair climbing). Cycling was not allowed. Clinical outcomes were assessed up to 24 months after intervention at 6 timepoints using patient reported-outcome measures Western Ontario and McMaster Universities Osteoarthritis (WOMAC) range 0-100; Visual Analogue Scale (VAS), range 0-100 for pain. Minimum joint space width (mJSW) was assessed using knee images digital analysis (KIDA) and articular cartilage volume with magnetic resonance imaging (MRI) using custom software at baseline and at 12 and 24 months follow-up.

RESULTS

Clinically beneficial effects were found for functioning (WOMAC improvement compared to baseline ranged between 18 points at 3 months follow-up and 31 points at 12 months follow-up, with only the 24-months follow-up (improvement of 27 points) not reaching statistical significance (p< 0.05)) and for pain (VAS improvement compared to baseline at follow-up time points ranged between 41-56 points; all p< 0.05). No improvements in mJSW- or MRI-derived parameters were found.

CONCLUSION

This study demonstrates that use of a custom-made knee-unloading orthosis for 60 days can result in improved functional ability and decrease in pain in relatively young patients with knee osteoarthritis. No effect on disease progression could be evidenced.

Harnessing joint distraction for the treatment of osteoarthritis: a bibliometric and visualized analysis

Osteoarthritis (OA) stands as a prevalent degenerative joint ailment, demanding immediate attention towards the development of efficacious therapeutic interventions. Presently, a definitive cure for OA remains elusive, and when conservative treatment modalities prove ineffective, resorting to a joint prosthesis becomes imperative. Temporary distraction emerges as a pivotal joint-preserving intervention in human OA patients, conferring both clinical amelioration and structural enhancements. Although extant clinical investigations exist, they are characterized by relatively modest sample sizes. Nonetheless, these studies furnish compelling evidence affirming that joint distraction engenders sustained clinical amelioration and structural refinement. Despite substantial strides in the last decade, a bibliometric analysis of joint distraction within the realm of osteoarthritis treatment research has been conspicuously absent. In this context, we have undertaken a comparative investigation utilizing bibliometric methodologies to scrutinize the landscape of joint distraction within osteoarthritis treatment. Our comprehensive analysis encompassed 469 scholarly articles. Our findings evince a consistent escalation in global research interest and publication output pertaining to this subject. The United States emerged as the frontrunner in international collaboration, publication count, and citation frequency, underscoring its preeminence in this domain. The journal "Osteoarthritis and Cartilage" emerged as the principal platform for disseminating research output on this subject. Notably, Mastbergen SC emerged as the most prolific contributor in terms of authorship. The identified keywords predominantly revolved around non-surgical interventions and joint arthroscopy procedures. This bibliometric analysis, augmented by visual representations, furnishes invaluable insights into the evolutionary trajectory of joint distraction as an osteoarthritis treatment modality spanning from 2003 to 2023. These insights will serve as a compass for the scientific community, facilitating further exploration in this promising domain.

Joint distraction using a purpose-built device for knee osteoarthritis: a prospective 2-year follow-up

OBJECTIVE

Knee distraction treatment for end-stage osteoarthritis successfully postpones arthroplasty for years. Studies performed thus far used general intended use, patient-personalised or custom-made devices. In this study, for the first time, a device specifically designed for knee distraction is evaluated.

DESIGN

65 patients (≤65 years) with end-stage knee osteoarthritis indicated for arthroplasty received knee distraction. Before, 1-year and 2-year post-treatment, questionnaires were filled out and knee radiographs made. Adverse events and self-reported pain medication were registered.

RESULTS

Forty-nine patients completed 2-year follow-up: one patient did not complete treatment, three patients received arthroplasty in the first and four patients in the second year follow-up. Eight patients were lost to follow-up in the second year. The total Western Ontario and McMaster Universities Osteoarthritis Index score showed a clinically relevant improvement at 1 and 2 years (+26 and +24 points), as did all subscales (all p<0.001). The minimum radiographic joint space width improved over 1 (+0.5 mm; p<0.001) and 2 (+0.4 mm; p=0.015) years, as did the physical Short-Form 36 (+10 points; p<0.001). The most common adverse event was pin tract infection, experienced by 66% of patients, in 88% successfully treated with oral antibiotics. In two cases, hospitalisation and/or intravenous antibiotics were needed. Eight patients experienced device-related complications. None of the complications influenced 2-year outcomes. Before treatment, 42% of patients used pain medication, which had nearly been halved 1 (23%; p=0.02) and 2 years (29%; p=0.27) post-treatment.

CONCLUSIONS

Patients treated with a general applicable, for knee distraction purpose-built device showed, despite adverse events, significant clinical and structural improvement over 2 years.

TRIAL REGISTRATION NUMBER

NL7986.

Can Technology Assistance be Cost Effective in TKA? A Simulation-Based Analysis of a Risk-prioritized, Practice-specific Framework

BACKGROUND

Robotic, navigated, and patient-specific instrumentation (PSI) TKA procedures have been introduced to improve component placement precision and improve implant survivorship and other clinical outcomes. However, the best available evidence has shown that these technologies are ineffective in reducing revision rates in the general TKA patient population. Nonetheless, it seems plausible that these technologies could be an effective and cost-effective means of reducing revision risk in clinical populations that are at an elevated risk of revision because of patient-specific demographics (such as older age at index surgery, elevated BMI, and being a man). Since clinical trials on this topic would need to be very large, a simulation approach could provide insight on which clinical populations would be the most promising for analysis.

QUESTIONS/PURPOSES

We conducted a simulation-based analysis and asked: (1) Given key demographic parameters characterizing a patient population, together with estimates of the precision achievable with selected forms of technology assistance in TKA, can we estimate the expected distributions of anticipated reductions in lifetime revision risk for that population and the associated improvements in quality-adjusted life years (QALYs) that would be expected to result? (2) Are there realistic practice characteristics (such as combinations of local patient demographics and capital and per-procedure costs) for which applying a per-patient risk-prioritized policy for using technology-assisted TKA could be considered cost-effective based on projected cost savings from reductions in revision rates?

METHODS

We designed simulations of hypothetical practice-specific clinical scenarios, each characterized by patient volume, patient demographics, and technology-assisted surgical technique, using demographic information drawn from other studies to characterize two contrasting simulated clinical scenarios in which the distributions of factors describing patients undergoing TKA place one population at a comparatively elevated risk of revision (elevated-risk population) and the second at a comparatively reduced risk of revision (lower-risk population). We used results from previous systematic reviews and meta-analyses to estimate the implant precision in coronal plane alignment for patient-specific instrumentation, navigated, and robotic technology. We generated simulated TKA patient populations based on risk estimates from large clinical studies, structured reviews, and meta-analyses and calculated the patient-specific reduction in the revision risk and the change in QALYs attributable to the technology-assisted intervention in each of the two simulated clinical scenarios. We also incorporated a sensitivity analysis, incorporating variations in the effect size of deviations from overall coronal alignment on revision risk and difference in health state utilities acquired through a structured review process. We then simulated the outcomes of 25,000 operations per patient using the precisions associated with the conventional TKA technique, the three technology-assisted techniques, and a hypothetical technology-assisted intervention that could consistently deliver perfectly neutral overall coronal alignment, which is unachievable in practice. A risk-prioritized treatment policy was emulated by ordering the simulated patients from the highest to lowest predicted increase in QALYs, such that simulated patients who would see the greatest increase in the QALYs (and therefore the greatest reduction in lifetime revision risk) were the patients to receive technology-assisted TKA intervention in a practice. We used cost estimates acquired through a structured review process and calculated the net added costs of each of the three technology-assisted techniques as a function of the percent utilization (proportion of patients treated with technology assistance in a practice), factoring in fixed costs, per-procedure variable costs, and savings occurring from the prevention of future revision surgery. Finally, we calculated the incremental cost-effectiveness ratio (ICER) and marginal cost-effectiveness ratio (MCER) for each technology-assisted technique for the two clinical scenarios. We then used a Monte Carlo approach to simulate variations in key patient risk, health state, and economic factors as well as to obtain a distribution of estimates for cost-effectiveness. We considered an intervention to be cost effective if either the ICER or MCER values were below USD/QALY 63,000.

RESULTS

For the lower-risk population, the median reduction in the revision risk was 0.9% (0.4% to 2.2%, extrema from the sensitivity analysis) and 1.8% (0.9% to 4.4%) for PSI and robotic TKA, respectively, and 1.9% (1.0% to 4.6%) for ideal TKA. In contrast, the median reduction in the revision risk in the elevated-risk clinical scenario was 2.0% (1.2% to 3.4%) and 4.6% (2.7% to 8.5%) for PSI and robotic TKA and 5.1% (3.0% to 9.4%) for ideal TKA. Estimated differences in the cumulative gain in QALYs attributable to technology-assisted TKA ranged from 0.6 (0.2 to 1.8) to 4.0 (1.8 to 10.0) QALYs per 100 patients, depending on the intervention type and clinical scenario. For PSI, we found treating 15% of patients in the lower-risk population and 77% in the elevated-risk population could meet the threshold for being considered cost effective. For navigated TKA systems offering high alignment precision, we found the intervention could meet this threshold for practice sizes of at least 300 patients per year and a percent utilization of 27% in the lower-risk population. In the elevated-risk population, cost-effectiveness could be achieved in practice volumes as small as 100 patients per year with a percent utilization of at least 6%, and cost savings could be achieved with a percent utilization of at least 45%. We found that robotic TKA could only meet the threshold for being considered cost-effectiveness in the lower-risk population if yearly patient volumes exceeded 600 and for a limited range of percent utilization (27% to 32%). However, in the elevated-risk patient population, robotic TKA with high alignment precision could potentially be cost effective for practice sizes as small as 100 patients per year and a percent utilization of at least 20% if a risk-prioritized treatment protocol were used.

CONCLUSION

Based on these simulations, a selective-use policy for technology-assisted TKA that prioritizes using technology assistance for those patients at a higher risk of revision based on patient-specific factors could potentially meet the cost-effectiveness threshold in selected circumstances (for example, primarily in elevated-risk populations and larger practice sizes). Whether it does meet that threshold would depend significantly on the surgical precision that can be achieved in practice for a given proposed technology as well as on the true local costs of using the proposed technology. We further recommend that any future randomized trials seeking to demonstrate possible effects of technology assistance on revision risk focus on clinical populations that are at higher risk of revision (such as, patient populations that are relatively younger, have higher BMIs, and higher proportions of men).

CLINICAL RELEVANCE

This study suggests that technology assistance is only likely to prove cost effective in selected circumstances rather than in all clinical populations and practice settings. In general, we project that surgical navigation is most likely to prove cost effective in the widest range of circumstances, that PSI may be cost effective or cost neutral in a moderate range of circumstances, and that robotic surgery is only likely to be cost effective in moderately large practices containing patients who are on average at an intrinsically elevated risk of revision.

Clinical and cost-effectiveness of Knee Arthroplasty versus Joint Distraction for Osteoarthritis (KARDS): protocol for a multicentre, phase III, randomised control trial

INTRODUCTION

Knee replacement (KR) is a clinically proven procedure typically offered to patients with severe knee osteoarthritis (OA) to relieve pain and improve quality of life. However, artificial joints fail over time, requiring revision associated with higher mortality and inferior outcomes. With more young people presenting with knee OA and increasing life expectancy, there is an unmet need to postpone time to first KR. Knee joint distraction (KJD), the practice of using external fixators to open up knee joint space, is proposed as potentially effective to preserve the joint following initial studies in the Netherlands, however, has not been researched within an NHS setting. The KARDS trial will investigate whether KJD is non-inferior to KR in terms of patient-reported postoperative pain 12 months post-surgery.

METHODS AND ANALYSIS

KARDS is a phase III, multicentre, pragmatic, open-label, individually randomised controlled non-inferiority trial comparing KJD with KR in patients with severe knee OA, employing a hybrid-expertise design, with internal pilot phase and process evaluation. 344 participants will be randomised (1:1) to KJD or KR. The primary outcome measure is the Knee Injury and Osteoarthritis Outcomes Score (KOOS) pain domain score at 12 months post-operation. Secondary outcome measures include patient-reported overall KOOS, Pain Visual Analogue Scale and Oxford Knee Scores, knee function assessments, joint space width, complications and further interventions over 24 months post-operation. Per patient cost difference between KR and KJD and cost per quality-adjusted life year (QALY) gained over 24 months will be estimated within trial, and incremental cost per QALY gained over 20 years by KJD relative to KR predicted using decision analytic modelling.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the Research Ethics Committee (REC) and Health Research Authority (HRA). Trial results will be disseminated at clinical conferences, through relevant patient groups and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN14879004; recruitment opened April 2021.

Cerebral mechanism of opposing needling for managing acute pain after unilateral total knee arthroplasty: study protocol for a randomized, sham-controlled clinical trial

Background

Opposing needling is a unique method used in acupuncture therapy to relieve pain, acting on the side contralateral to the pain. Although opposing needling has been used to treat pain in various diseases, it is not clear how opposing needling affects the activity of the central nervous system to relieve acute pain. We herein present the protocol for a randomized sham-controlled clinical trial aiming to explore the cerebral mechanism of opposing needling for managing acute pain after unilateral total knee arthroplasty (TKA).

Methods

This is a randomized sham-controlled single-blind clinical trial. Patients will be allocated randomly to two parallel groups (A: opposing electroacupuncture group; B: sham opposing electroacupuncture group). The Yinlingquan (SP9), Yanglingquan (GB34), Futu (ST32), and Zusanli (ST36) acupoints will be used as the opposing needling sites in both groups. In group A, the healthy lower limbs will receive electroacupuncture, while in group B, the healthy lower limbs will receive sham electroacupuncture. At 72 h after unilateral TKA, patients in both groups will begin treatment once per day for 3 days. Functional magnetic resonance imaging will be performed on all patients before the intervention, after unilateral TKA, and at the end of the intervention to detect changes in brain activity. Changes in pressure pain thresholds will be used as the main outcome for the improvement of knee joint pain. Secondary outcome indicators will include the visual analogue scale (including pain during rest and activity) and a 4-m walking test. Surface electromyography, additional analgesia use, the self-rating anxiety scale, and the self-rating depression scale will be used as additional outcome indices.

Discussion

The results will reveal the influence of opposing needling on cerebral activity in patients with acute pain after unilateral TKA and the possible relationship between cerebral activity changes and improvement of clinical variables, which may indicate the central mechanism of opposing needling in managing acute pain after unilateral TKA.

Trial registration

Study on the brain central mechanism of opposing needling analgesia after total kneearthroplasty based on multimodal MRI ChiCTR2100042429. Registered on January 21, 2021

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06066-6.

Role of joint distraction in osteoarthritis of the knee: Basic science, principles and outcomes

The burden of knee osteoarthritis (OA) is increasing worldwide. Advanced tibiofemoral joint OA in young patients is particularly a problem with inferior results seen with total knee arthroplasty in this patient population. Knee joint distraction (KJD) has been evaluated recently as a joint preserving procedure for young patients with advanced tibiofemoral osteoarthritis, to delay the need for a primary total knee arthroplasty (TKA). This will decrease the risk for revision TKA later in life. KJD temporarily unloads the knee joint and keeps the tibia and femur separated over a course of 6 weeks. Outcomes of KJD appear promising. Through this article, the authors hope to share from their collective experience as well as the available literature on the basic science, principles of surgery and outcomes of KJD.

Knee Joint Distraction as Treatment for Osteoarthritis Results in Clinical and Structural Benefit: A Systematic Review and Meta-Analysis of the Limited Number of Studies and Patients Available

OBJECTIVE

Knee joint distraction (KJD) is a joint-preserving osteoarthritis treatment that may postpone a total knee arthroplasty (TKA) in younger patients. This systematic review and meta-analysis evaluates short- and long-term clinical benefit and tissue structure changes after KJD.

DESIGN

MEDLINE, EMBASE, and Web of Science were searched for eligible clinical studies evaluating at least one of the primary parameters: WOMAC, VAS-pain, KOOS, EQ5D, radiographic joint space width or MRI cartilage thickness after KJD. Random effects models were applied on all outcome parameters and outcomes were compared with control groups found in the included studies.

RESULTS

Eleven articles reporting on 7 different KJD cohorts with in total 127 patients and 5 control groups with multiple follow-up moments were included, of which 2 were randomized controlled trials. Significant improvements in all primary parameters were found and benefit lasted up to at least 9 years. Overall, outcomes were comparable with control groups, including high tibial osteotomy, although TKA showed better clinical response.

CONCLUSIONS

Current, still limited, evidence shows KJD causes clear benefit in clinical and structural parameters, both short- and long-term. Longer follow-up with more patients is necessary, to validate outcome and to potentially improve patient selection for this intensive treatment. Thus far, for younger knee osteoarthritis patients, KJD may be an option to consider.

Performance of knee image digital analysis of radiographs of patients with end-stage knee osteoarthritis

OBJECTIVE

Knee Image Digital Analysis (KIDA) is standardized radiographic analysis software for measuring osteoarthritis (OA) characteristics. It was validated in mild OA, but used for severe OA as well. The current goal was to evaluate the performance of KIDA in severe OA.

DESIGN

Of 103 patients, standardized radiographs were performed before and one and 2 years after treatment for severe OA. All radiographs were evaluated on subchondral bone density, joint space width (JSW), osteophytes, eminence height, and joint angle, twice within years by the same observer. Part of the radiographs were randomly selected for reevaluation twice within 1 month and evaluation by another observer. The intraclass correlation coefficient (ICC), smallest detectable difference (SDD) and coefficient of variation (CV) were calculated; the SDD and CV were compared to those in mild OA. The relation of severity with KIDA parameters and with observer differences was calculated with linear regression.

RESULTS

Intra-observer ICCs were higher in the 98 severe radiographs reanalyzed within 1 month (all >0.8) than the 293 reanalyzed within years (all >0.5; most >0.8) and than inter-observer ICCs (all >0.7). SDDs and CVs were smaller when reanalyzed within a month and comparable to those in mild OA. Some parameters showed bias between readings. Severity showed significant relation with osteophytes and JSW parameters, and with the observer variation in these parameters (all P < 0.04).

CONCLUSIONS

KIDA is a well-performing tool also for severe OA. In order to decrease variability and SDDs, images should be analyzed in a limited time frame and randomized order.

Knee Joint Distraction Compared with High Tibial Osteotomy and Total Knee Arthroplasty: Two-Year Clinical, Radiographic, and Biochemical Marker Outcomes of Two Randomized Controlled Trials

OBJECTIVE

Both, knee joint distraction (KJD) and high tibial osteotomy (HTO) are joint-preserving surgeries that postpone total knee arthroplasty (TKA) in younger osteoarthritis (OA) patients. Here we evaluate the 2-year follow-up of KJD versus TKA and KJD versus HTO in 2 noninferiority studies.

DESIGN

Knee OA patients indicated for TKA were randomized to KJD (n = 20; KJD_TKA) or TKA (n = 40). Medial compartmental knee OA patients considered for HTO were randomized to KJD (n = 23; KJD_HTO) or HTO (n = 46). Patient-reported outcome measures were assessed over 2 years of follow-up. The radiographic joint space width (JSW) was measured yearly. In the KJD groups, serum-PIIANP and urinary-CTXII levels were measured as collagen type-II synthesis and breakdown markers. It was hypothesized that there was no clinically important difference in the primary outcome, the total WOMAC, when comparing KJD with HTO and with TKA.

RESULTS

Both trials were completed, with 114 patients (19 KJD_TKA; 34 TKA; 20 KJD_HTO; 41 HTO) available for 2-year analyses. At 2 years, the total WOMAC score (KJDTKA: +30.4 [95% CI 23.0-37.9] points; TKA: +42.4 [95% CI 38.1-46.8]; KJDHTO: +21.6 [95% CI 13.8-29.4]; HTO: +29.2 [95% CI 23.6-34.8]; all: P < 0.05) and radiographic minimum JSW (KJDTKA: +0.9 [95% CI 0.2-1.6] mm; KJDHTO: +0.9 [95% CI 0.5-1.4]; HTO: +0.6 [95% CI 0.3-0.9]; all: P < 0.05) were still increased for all groups. The net collagen type-II synthesis 2 years after KJD was increased (P < 0.05). Half of KJD patients experienced pin tract infections, successfully treated with oral antibiotics.

CONCLUSIONS

Sustained improvement of clinical benefit and (hyaline) cartilage thickness increase after KJD is demonstrated. KJD was clinically noninferior to HTO and TKA in the primary outcome.

Modelling the cost-effectiveness of total knee arthroplasty: A systematic review

Objective

Osteoarthritis causes a significant healthcare burden and the number of total knee arthroplasty (TKA) procedures is predicted to increase significantly in the coming years. We conducted a systematic review to assess the scope and quality of all current TKA cost-effectiveness analysis (CEA) studies, identify trends, and identify areas for improvement.

Methods

An electronic database search of MEDLINE, Embase, the CEA registry and Scopus was used to identify all CEA studies where TKA was used with a comparator. Studies were included from January 1, 1997 to February 2, 2020. The Quality of Health Economic Analysis Studies (QHES) instrument was used to assess their quality. Thirty-three studies were included that offered both a QALY and cost calculation. The main findings, incremental-cost effectiveness ratios and other important study characteristics were then ascertained, and trends identified.

Results

Certain surgical interventions were suggested to be more cost-effective than TKA. This included unicompartmental knee arthroplasty for unicompartmental osteoarthritis, computer-assisted TKA compared to conventional TKA, and resurfacing the patella compared to no resurfacing. TKA was more cost-effective compared to non-operative management regardless of specific patient variables.

Conclusions

The analyses of the CEAs included in the study have to be interpreted with caution. Overall, certain surgical methods within TKA and alternative methods to TKA appear to be favoured for treating particular knee osteoarthritic conditions due to their suggested greater cost-effectiveness but this should be interpreted within local contexts. Our results should help guide future policy-making as healthcare associated costs continue to rise.

Gait Analysis after Total Knee Arthroplasty Assisted by 3D-Printed Personalized Guide

Background

With the development of three-dimensional printing (3DP) technology, the patient-specific instrumentation (PSI) has been widely applied in total knee arthroplasty (TKA). The purpose of this study was to compare the gait parameters of patients with 3DP personalized guide-assisted and standard TKA.

Methods

Retrospective analysis of the advanced knee OA cases in our hospital between June 2017 and June 2018 was conducted. 30 cases received 3DP personalized guide-assisted TKA (group A), and 60 patients who underwent standard TKA during the same period were in group B and group C according to the computed tomography (CT) measurement results, each with 30 cases. Hip–knee–ankle angle (HKA), patella transverse axis-femoral transepicondylar axis angle (PFA), and gait parameters were statistically analyzed. The function was assessed by Hospital for Specific Surgery (HSS) and Knee Society Score (KSS).

Results

The mean follow-up period was 12.3 months in the three groups. The knee max flexion angle at the swing phase of group A was larger than group B and group C (P < 0.05), there was no statistically significant difference in other gait parameters. The mean PFA of group A was smaller than that of group B and group C (P < 0.05). While, the HKA, HSS, and KSS scores of three groups showed no significant difference.

Conclusion

3DP personalized guide technology could improve the gait parameters after surgery, specifically reflected in the knee max flexion angle at the swing phase. It could also assist in the reconstruction of more accurate patellar tracking and rotational alignment in TKA, avoiding the occurrence of insufficient or excessive extorsion.

Barbed suture versus traditional suture in primary total knee arthroplasty: A systematic review and meta-analysis of randomized controlled studies

BACKGROUND

Barbed suture has been widely used in some surgical fields, and it has achieved good results, but the application in total knee arthroplasty is still controversial.

OBJECTIVE

Literature is collected for statistical analysis so as to provide evidence for the use of barbed suture in Total knee arthroplasty.

METHODS

We searched PubMed, the Cochrane library and EMBASE database for randomized controlled trials (RCTs) using barbed suture and conventional suture to close incisions after primary total knee arthroplasty, and the retrieval time was from July 2019 to the establishment of the database. Literature was screened according to inclusion and exclusion criteria, quality evaluation and data extraction were conducted for the final included literature, and statistical analysis was conducted using RevMan 5.3 software.

RESULTS

A total of six RCTs (826 knees) were included in our meta-analysis. The results showed that the re-negative conversion could shorten the wound closure time (MD -4.41, 95% CI -5.11 to -3.72, P < .00001) and reduce the wound closure total cost (MD -282.61, 95% CI -445.36 to -119.85, P = .0007) and acupuncture injury (RR 0.14, 95% CI 0.03-0.78, P = .02), and did not significantly increasing the incidence of complications (RR 0.80, 95% CI 0.05-0.96, P = .38) or suture breakages (RR 4.58, 95% CI 0.16-128.29, P = .37). There were no significant differences in ROM at postoperative 6 weeks and 3 months (MD -0.74, 95% CI -4.19 to 2.71, P = .67; MD -0.30, 95% CI -2.62 to 2.02, P = .80) and no significant differences in KSS at postoperative 6 weeks (MD -0.22, 95% CI -3.10 to 2.66, P = .88).

CONCLUSIONS

Our study shows that barbed suture is a fast, low-cost, safe and effective suture method in total knee arthroplasty compared with traditional suture, we also need more literature and longer follow-up to confirm this conclusion.

The molecular profile of synovial fluid changes upon joint distraction and is associated with clinical response in knee osteoarthritis

OBJECTIVE

Surgical knee joint distraction (KJD) leads to clinical improvement in knee osteoarthritis (OA) and also apparent cartilage regeneration by magnetic resonance imaging. We investigated if alteration of the joint's mechanical environment during the 6 week period of KJD was associated with a molecular response in synovial fluid, and if any change was associated with clinical response.

METHOD

20 individuals undergoing KJD for symptomatic radiographic knee OA had SF sampled at baseline, midpoint and endpoint of distraction (6 weeks). SF supernatants were measured by immunoassay for 10 predefined mechanosensitive molecules identified in our previous pre-clinical studies. The composite Knee injury and OA Outcome Score-4 (KOOS₄) was collected at baseline, 3, 6 and 12 months.

RESULTS

13/20 (65%) were male with mean age 54°±°5yrs. All had Kellgren-Lawrence grade ≥2 knee OA. 6/10 analytes showed statistically significant change in SF over the 6 weeks distraction (activin A; TGFβ-1; MCP-1; IL-6; FGF-2; LTBP2), P < 0.05. Of these, all but activin A increased. Those achieving the minimum clinically important difference of 10 points for KOOS₄ over 6 months showed greater increases in FGF-2 and TGFβ-1 than non-responders. An increase in IL-8 during the 6 weeks of KJD was associated with significantly greater improvement in KOOS₄ over 12 months.

CONCLUSION

Detectable, significant molecular changes are observed in SF following KJD, that are remarkably consistent between individuals. Preliminary findings appear to suggest that increases in some molecules are associated with clinically meaningful responses. Joint distraction may provide a potential opportunity in the future to define regenerative biomarker(s) and identify pathways that drive intrinsic cartilage repair.

Knee joint distraction in regular care for treatment of knee osteoarthritis: A comparison with clinical trial data

Objectives

Knee joint distraction (KJD) has been evaluated as a joint-preserving treatment to postpone total knee arthroplasty in knee osteoarthritis patients in three clinical trials. Since 2014 the treatment is used in regular care in some hospitals, which might lead to a deviation from the original indication and decreased treatment outcome. In this study, baseline characteristics, complications and clinical benefit are compared between patients treated in regular care and in clinical trials.

Methods

In our hospital, 84 patients were treated in regular care for 6 weeks with KJD. Surgical details, complications, and range of motion were assessed from patient hospital charts. Patient-reported outcome measures were evaluated in regular care before and one year after treatment. Trial patients (n = 62) were treated and followed as described in literature.

Results

Patient characteristics were not significantly different between groups, except for distraction duration (regular care 45.3±4.3; clinical trials 48.1±8.1 days; p = 0.019). Pin tract infections were the most occurring complication (70% regular care; 66% clinical trials), but there was no significant difference in treatment complications between groups (p>0.1). The range of motion was recovered within a year after treatment for both groups. WOMAC questionnaires showed statistically and clinically significant improvement for both groups (both p<0.001 and >15 points in all subscales) and no significant differences between groups (all differences p>0.05). After one year, 70% of patients were responders (regular care 61%, trial 75%; p = 0.120). Neither regular care compared to clinical trial, nor any other characteristic could predict clinical response.

Conclusions

KJD as joint-preserving treatment in clinical practice, to postpone arthroplasty for end-stage knee osteoarthritis patient below the age of 65, results in an outcome similar to that thus far demonstrated in clinical trials. Longer follow-up in regular care is needed to test whether also long-term results remain beneficial and comparable to trial data.

Downregulation of the long noncoding RNA MBNL1-AS1 protects sevoflurane-pretreated mice against ischemia-reperfusion injury by targeting KCNMA1

Total knee arthroplasty (TKA) is the most common and cost-effective treatment for older adults with long-standing osteoarthritis. During TKA, muscle cells suffer from prolonged oxygen deficiency, which leads to altered cell metabolism that reduces the energy demand and maintains cell homeostasis before blood flow is restored. This study focused on the role of the lncRNA muscleblind-like 1 antisense RNA 1 (MBNL1-AS1) in protecting sevoflurane-pretreated mice against ischemia-reperfusion (I/R) injury after TKA, as well as the elucidation of the potential associated mechanism. Identification of differentially expressed lncRNAs was performed using the microarray dataset GSE21164, which was extracted from the GEO database. Target genes of the lncRNA were determined using Multi-Experiment Matrix (MEM), a dual-luciferase reporter gene assay, and KEGG enrichment analyses. The results showed that MBNL1-AS1 was overexpressed in skeletal muscle cells in mice, while KCNMA1, which was enriched in the cGMP-PKG signaling pathway, was negatively regulated by MBNL1-AS1. Furthermore, I/R mice displayed serious inflammatory reactions. Down-regulation of MBNL1-AS1 increased the expression of KCNMA1, PKGII, VASP, VEGF, Bcl-2, Cyclin D1, Cyclin D3, and Cdc 42 but decreased the expression of Bax, cleaved caspase-3, and cleaved PARP. Furthermore, upon MBNL1-AS1 upregulation, the rate of cell apoptosis increased while the rate of cell proliferation decreased. Our data suggested that down-regulated lncRNA MBNL1-AS1 might promote the proliferation and inhibit the apoptosis of skeletal muscle cells by upregulating KCNMA1 expression via activation of the cGMP-PKG signaling pathway, thus protecting sevoflurane-pretreated mice against I/R injury after TKA.

A potential therapeutic target identified by researchers in China could help limit damage to tissues following osteoarthritic knee surgery. A total knee arthroplasty can alleviate symptoms of end-stage osteoarthritis, but the surgery requires use of a tourniquet. This temporarily cuts blood supply to tissues and can trigger severe ischemia-reperfusion (I/R) injury, tissue damage caused by blood flow returning after oxygen deficiency. Shao-Nan Yu and co-workers at the China-Japan Union Hospital of Jilin University, Changchun, demonstrated that lowering expression of a particular RNA molecule following surgery could limit I/R damage. They found that the molecule was over-expressed in mice during I/R injury. This overexpression limited activation of a signalling pathway and an associated protein vital to the chemical balance of cell membranes and healthy muscle cell contraction.

Disease burden of knee osteoarthritis patients with a joint replacement compared to matched controls: a population-based analysis of a Dutch medical claims database

OBJECTIVE

On a population level, the incidence of knee prostheses (KPs) has increased, but excess health care costs per patient, compared to matched controls without a KP, in the years surrounding these procedures and their determinants are largely unknown. We therefore aimed to provide estimates of age- and sex-specific incidence of KPs, revision KPs, and prosthesis complications in patients with knee osteoarthritis (OA) and to determine excess health care costs in the years surrounding surgery compared with matched controls.

METHODS

All KPs in OA patients in the Achmea Health Database were identified as well as up to four controls. Incidence rates of KPs, revisions, and complications from 2006 to 2013 were determined. Annual health care cost and excess costs (over matched controls) preceding, during, and after surgery were calculated and their determinants were evaluated.

RESULTS

The increased incidence of KPs, revisions, and complications was strongest in younger age categories and men. The average costs per patient were relatively stable between 2006 and 2012. KP patient's annual health care costs increased towards the year of surgery. After surgery, costs decreased, but remained higher as compared to costs prior to surgery. High post-surgery costs were mainly associated with subsequent revisions or additional KPs, but costs were also higher in females, lower age categories, and lower social economic status.

CONCLUSION

These results underscore the increasing burden and medical need associated with end-stage OA, especially in younger age categories. Improvement of guidelines tailored to individual patient groups aimed at avoiding complications and revisions is required to counteract this increasing burden.