Advanced Knee Osteoarthritis Research Articles

A Randomized Double-Blind Prospective Study Comparing the Efficacy of Subperiosteal and Periarticular Injections of a Local Anesthetic for Postoperative Pain Management after Total Knee Arthroplasty.

Total knee arthroplasty (TKA) serves as an effective surgical treatment method for advanced osteoarthritis (OA). Nonetheless, it is associated with postoperative pain that can influence patients' functional outcome. This study aimed to compare the analgesic effect of subperiosteal and periarticular injection methods of a special local anesthetic in patients who underwent TKA. This double-blind prospective clinical study was conducted on patients with advanced knee OA who underwent TKA. Patients were randomly divided into two groups, with a local anesthetic (21 ml) administered either in periarticular (P group) or subperiosteal (S group) forms prior to wound closure. The local anesthetic consisted of lidocaine 2% (15 cc), dexmedetomidine (1 cc), and marcaine 0.5% (5 cc). A study-blinded orthopedic resident recorded postoperative pain levels using a 10-point visual analogue score (VAS) (0 indicating no pain, 10 indicating worst pain) at 6, 12, 24, and 48 hours after surgery. A total of 40 patients (P and S group; n=20 each), consisting of 10 males (mean age=67.4 years old), were included in this study. The intensity of pain in the S group was significantly lower than in the P group 24 hours after surgery (mean VAS scores in the P group: 4±1 vs. the S group: 3.3±0.7, P=0.024). Furthermore, VAS scores at 6, 12, and 48 hours post-surgery were lower in the S group compared to the P group; however, the difference was not statistically significant (P>0.05). Our study indicated that subperiosteal injection of lidocaine, dexmedetomidine, and marcaine is more effective than periarticular injection, providing effective postoperative pain management after TKA.

Body Composition and Bone Mineral Density in Postmenopausal Women with Advanced Knee Osteoarthritis Undergoing Surgical Treatment.

This study aimed to demonstrate the bone mineral density (BMD) and body composition in postmenopausal women with knee osteoarthritis (OA) who underwent surgical treatment, such as total knee arthroplasty, osteotomy, or meniscectomy. A total of 254 women with OA aged 50 years who underwent surgical treatment were enrolled in this study. We evaluated obesity-related factors, muscle components, and BMD using dual-energy X-ray absorptiometry. No significant differences were noted in the BMD of the hip joint between the symptomatic side of the leg with knee OA and the contralateral side. However, when comparing the BMD of each component, the results indicated a significantly higher BMD in the obesity group based on body mass index (BMI). When defining sarcopenic obesity (SO) using various indicators of obesity (BMI, the estimated visceral adipose tissue area, android/gynoid ratio, and total body fat percentage), the prevalence of SO in the OA group who underwent surgical treatment ranged from 22.0% to 49.6%. This study investigated obesity-related factors in patients with advanced knee OA who underwent surgery, revealing a high prevalence of overweight/obese individuals, the presence of SO, and a complex relationship between obesity, body composition, and bone density, highlighting the potential protective effects of weight-bearing on bone health while exploring the impact of sarcopenia on bone density differences in the context of OA. Depending on various definitions of obesity, diverse proportions of SO in patients with OA have been observed, and further detailed research is required to understand its impact on the condition.

No-synovectomy improves the health-related quality of life after total knee arthroplasty: A randomised clinical trial

Abstract Background This study assessed the clinical outcomes of total knee replacement with and without synovectomy among patients with osteoarthritis. Methods A randomised controlled trial of 70 patients with advanced knee osteoarthritis was conducted by individually randomizing (simple randomization) patients to either no synovectomy (group 1 n=35) or synovectomy (group 2 n=35). Clinical outcomes were assessed by Western Ontario and McMaster Universities Arthritis Index, WOMAC score, knee pain by visual analogue score, health related quality of life by Short Form 12, postoperative blood loss, and hemoglobin levels immediately after surgery and one year postoperative. Results Postoperatively, The WOMAC score was 87 (82, 97) in group 1 and 84 (76, 96) in group 2. The VAS score was 6 (5.00, 8.00) and 7 (5.00, 8.00) in group 1 and 2 respectively. The physical composite score (PCS) of the SF-12 score was 52 (46, 56) in group 1 and 50 (43, 54) in group 2. The mental composite score of the SF-12 was 58(55, 61) and 51 (45, 57) in group 1 and 2 respectively with significant difference between groups. The median hemoglobin drop was 1.7 (1.35, 2.00) grams in group 1 and 3 (2.45, 3.30) grams in group 2. The median drain blood loss was 250 ml (200, 350) and 800 ml (450, 1200) in group 1 and 2 respectively. Patients in group 1 had a better flexion range than group 2. Conclusion Total knee arthroplasty performed without synovectomy reduces postoperative blood loss, improves the flexion range and patients’ quality of life scores.

Static Plantar Pressure Distribution and Position Correlations in Early and Mid-term Knee Osteoarthritis Patients

Background: Knee osteoarthritis (KOA) is the most common degenerative joint disease, and patients will develop abnormalities in the movement model. Plantar pressure distribution and body postural characteristics may differ in patients with KOA compared to healthy adults and may affect physical function in these patients. At present, most related studies focus on patients with advanced KOA, and there are few studies on patients in early and middle stages. This study aims to apply the plantar pressure detection and human joint point identification technology to explore the characteristics of body posture and plantar pressure distribution in the early and middle-term KOA patients. Materials and Methods: Data from 38 middle and early KOA patients (age =54.58 ± 7.32 years) and 28 healthy volunteers (age =54.93 ± 7.90 years including), lower limb weight bearing, peak foot pressure distribution, pressure center (center of pressure [CoP]) offset, offset area, Q angle, pelvic position, spine offset, and other data were compared by statistical analysis of independent sample t-test and Pearson’s Chi-square test. Result: The results showed that the foot pressure in the early and mid-term KOA patients tended to be distributed in the medial heel, and the body CoP swing range was smaller than that in the control group (P < 0.05). In addition, patients in the KOA group had a larger left Q angle than the control group and had a smaller rate of right pelvis bias (P < 0.05). There was no statistical difference in lower limb weight bearing and spinal posture between the two groups. Conclusion: In standing conditions, patients in the KOA group have exhibited abnormal postural patterns and foot pressure distribution in the early and middle stages compared with healthy volunteers. Assessment of plantar pressure distribution, pelvic position, and positioning of lower limb joints may be important for evaluating patients with KOA. Keywords: Knee osteoarthritis, Plantar pressure, Posture

The Effect of Intramedullary vs Extramedullary Tibial Guides on the Alignment of Lower Extremity and Functional Outcomes Following Total Knee Arthroplasty: A Randomized Clinical Trial.

Total knee arthroplasty (TKA) has been known as a definitive treatment for advanced knee osteoarthritis. Both intramedullary (IM) and extramedullary (EM) tibial guides have been used to restore the desired extremity alignment. However, controversy exists regarding the superiority of either technique We aimed to compare the functional outcomes and accuracy of IM and EM tibial guides in providing neutral alignment after TKA. In a randomized, double-blinded clinical trial, we studied 98 patients undergoing primary TKA in two groups of IM and EM. We measured the medial proximal tibial angle (MPTA), varus angle (VA), and joint-line convergence angle with normal ranges of 90°±3°, 0-2°, and 0±3°, respectively, on a three-joint alignment view after three months. We also assessed the functional outcomes at the last follow-up. Finally, we compared these outcomes between the two groups. Eighty-four patients (IM=42, EM=42) were included in the final analysis (16 males, 68 females, mean age: 63.9±8.6 years, mean follow-up: 13±2.9 months). The mean postoperative (post-op) alignment angles showed no significant difference, although MPTA outliers were significantly more frequent in the EM group (26.2% vs. 9.5% in IM, P=0.04). None of the functional outcomes showed a significant difference between the two groups. However, the mean increase in knee range of motion (ROM) was significantly higher in the knees with VAs within ±3° of neutral than those outside this range (30.8 vs. 27.4, respectively, P=0.039). We conclude that both techniques were not different regarding the mean alignment angles and functional outcomes. However, fewer MPTA outliers can be seen with the IM technique. A post-op mechanical axis within ±3° of neutral can result in a more ROM increase after one year.

Variation in the utilisation of physiotherapy in patients with advanced knee osteoarthritis prior to total knee arthroplasty a systematic review.

Due to demographic changes and increasing knee osteoarthritis (KOA) prevalence, the incidence of total knee arthroplasties (TKA) is constantly rising. Clinical practice guidelines for the treatment of KOA unanimously recommend non-surgical interventions such as exercise, education, and weight reduction in overweight patients. The aim of this systematic review is to determine the proportion of patients with end-stage KOA who attended physiotherapy (PT) prior to TKA. A systematic literature search was carried out in the medical databases MEDLINE (via Pubmed), PEDro, and EBSCO in August of 2022. Studies were included regardless of their design, if they reported the proportion of patients with a diagnosis of primary KOA, who participated in PT prior to undergoing TKA. Study quality assessment was performed by two independent authors using the Joanna Briggs Institutes Checklist for studies reporting prevalence data. Results were presented by using a narrative synthesis. Eighteen studies, comprising 579,718 patients, were identified in this systematic review. PT utilisation prior to TKA ranged from 10% to 73% for patients with advanced KOA. Only two studies showed PT utilisation rates of 60% or higher. Female gender, higher income, better socioeconomic status, higher education levels, older age were associated with PT utilisation. Data for other predicting factors was conflicting. This review shows substantial variation in the utilisation of PT in patients with end-stage KOA. This is concerning, considering the uniform recommendation from clinical practice guidelines for non-surgical treatments like exercise and education in patients with KOA, which are mostly provided by physiotherapists.

Acute postoperative pain and dorsal root ganglia transcriptomic signatures following total knee arthroplasty (TKA) in rats: An experimental study.

Total knee arthroplasty (TKA) is the final treatment option for patients with advanced knee osteoarthritis (OA). Unfortunately, TKA surgery is accompanied by acute postoperative pain that is more severe than arthroplasty performed in other joints. Elucidating the molecular mechanisms specific to post-TKA pain necessitates an animal model that replicates clinical TKA procedures, induces acute postoperative pain, and leads to complete functional recovery. Here, we present a new preclinical TKA model in rats and report on functional and behavioral outcomes indicative of pain, analgesic efficacy, serum cytokine levels, and dorsal root ganglia (DRG) transcriptomes during the acute postoperative period. Following TKA, rats exhibited marked deficits in weight bearing that persisted for 28 days. Home cage locomotion, rearing, and gait were similarly impacted and recovered by day 14. Cytokine levels were elevated on postoperative days one and/or two. Treatment with morphine, ketorolac, or their combination improved weight bearing while gabapentin lacked efficacy. When TKA was performed in rats with OA, similar functional deficits and comparable recovery time courses were observed. Analysis of DRG transcriptomes revealed upregulation of transcripts linked to multiple molecular pathways including inflammation, MAPK signaling, and cytokine signaling and production. In summary, we developed a clinically relevant rat TKA model characterized by resolution of pain and functional recovery within five weeks and with pain-associated behavioral deficits that are partially alleviated by clinically administered analgesics, mirroring the postoperative experience of TKA patients.

Variability of functional knee phenotype for coronal alignment in advanced varus knee osteoarthritis in the Japanese population.

New concept of functional knee phenotypes in Caucasians demonstrated the variability of coronal alignment in knee osteoarthritis (OA), but it remains unclear in Japanese. This study aims to analyze the knee phenotype in advanced varus knee OA for Japanese. In addition, the ethnical difference is discussed. This study analyzed 879 knees involving 186 males (74years) and 693 females (74years). The knee phenotypes were assessed by the definition in Hirschmann's group. The hip-knee-ankle angle (HKA), femoral mechanical angle (FMA) and tibial mechanical angle (TMA) were assessed in CT data according to the coordinate system. The neutral angle was 180° in HKA, 93° in FMA and 87° in TMA. The smaller angle means larger varus angles. The average angle (males, females) of the HKA (170.9 ± 4.3°, 169.4 ± 5.0°), FMA (91.5 ± 2.7°, 90.6 ± 3.0°), and TMA (82.4 ± 3.6°, 82.7 ± 3.7°) demonstrated varus angles with the sex difference (HKA, p < 0.001; FMA, p = 0.001). The phenotypes were 73 types in males and 150 types in females with a mild correlation between the HKA and the FMA or TMA. In 61.3% of males and 52.2% of females, the TMA was greater than the FMA, while the FMA was greater in 16.7% of males and 23.1% of females. There were many functional knee phenotypes with sex differences for advanced varus knee OA in Japanese, showing ethnical differences of larger varus angles compared to those for Caucasians in the previous report. IV.

What's New in Adult Reconstructive Knee Surgery.

What's New in Adult Reconstructive Knee Surgery.

Overcoming the Technical Challenges of Total Knee Arthroplasty in Patients Affected by Hereditary Multiple Exostoses: a Case Report and Literature Review

Hereditary multiple exostoses (HME), also known as familiar osteochondromatosis or diaphyseal aclasis, are an autosomal dominant inherited genetic pathology that is characterized by the presence of multiple benign osteochondromas. Knee deformity is common in patients with HME, with nearly a third of patients developing genu valgus. Total knee arthroplasty (TKA) has been used to correct valgus deformities with advanced knee osteoarthritis (OA). However, concomitant limb deformities and altered anatomy of the knee make this surgery particularly challenging. We present a case report and a mini-review of the literature on this topic. We present the case of a 50-year-old Caucasian woman, affected by hereditary multiple exostoses, who came to our attention for progressive pain in the right knee. Upon further examination, the knee had a prominent valgus alignment, concomitant valgus instability, and flexion contraction. The patient was treated with total knee arthroplasty using a semi-constrained design. The patient was re-evaluated at 24-month follow-up, and there were no signs of implant loosening, the knee function improved significantly, and the patient was very satisfied. Given the recurring technical difficulties of such procedure in these patients, we describe our experience as well as the need for preoperative planning, the use of appropriate constraint when required, the high frequency of ligament instability, bony defects, and patellar maltracking. TKA must be considered when necessary, in these patients, as good to excellent clinical results can be achieved and maintained, allowing for significant improvements in quality of life.Core Tips- TKA in HME-affected patients carries specific but manageable challenges.- Due to bone deformities and frequent severe valgus knee alignment, TKA should be considered even in younger patients.- Revision implants provide the flexibility and the necessary fixation, not always achievable with primary implants.- Bigger size components may be necessary in HME patients compared with patients of the same height.- Lateral ligament releases may often be necessary due to long-standing valgus deformity. If stability cannot be achieved, the use of a hinged implant should be considered.- Cementation of the metaphysis or the use of sleeves can provide additional rotational stability to the implant.

Lateral shift of the femoral condyle after total knee arthroplasty: simulation using 2D-templates of the medial pivot design on knee radiographs of young Japanese patients

BackgroundTotal knee arthroplasty (TKA) is an established surgical treatment for advanced knee osteoarthritis by which patients can expect improvement of knee pain and function. Although many surgeons have investigated limb alignment after TKA, changes in coronal positional relation between the femur and tibia are not known well.MethodsRadiographs of 105 knees of young Japanese patients between 20 and 49 years-old (60 men and 45 women) without osteoarthritic changes who received arthroscopic surgeries at our hospital were used in this study. Using 2D-templates of the medial pivot design (the FINE total knee), we simulated TKA on a SYNAPSE-PACS software. First, the femoral component was placed in normal knee alignment and then was merged to the medial concave of the insert where the tibial component was placed in neutral alignment. The length of the mediolateral shift of the femoral component was measured as an estimate of lateral shift of the femoral condyle, of which association with radiographic parameters including the femorotibial angle (FTA), lateral distal femoral angle (LDFA), and medial proximal tibial angle (MPTA) was analyzed. Subjects were classified into three groups according to the femoral component size that was chosen in simulation of TKA, and the lateral shift of the femoral condyle was compared between groups.ResultsThe estimated mean lateral shift of the femoral condyle was 5.99 ± 1.98 mm and was greater in males than females (p < 0.05). Also, it was most highly correlated with the medial proximal tibial angle (MPTA) (r = − 0.553, p < 0.01). A group receiving larger component sizes significantly shifted more laterally compared with a group receiving smaller component sizes (p < 0.01).ConclusionsThese results suggest that the coronal positional relation between the femur and tibia is altered and subsequent ligament imbalance may occur after mechanically aligned TKA using the medial pivot design.

Tibial condylar valgus osteotomy for the treatment of intra-articular varus deformity of the knee.

The increasing incidence and distribution of primary and post-traumatic knee osteoarthritis (OA) in the young, active population has renewed interest in joint-preserving procedures. High tibial osteotomy (HTO) represents the most common treatment for medial knee OA associated with varus tibial deformity. However, deformities may also be related to intra-articular defects that an extra-articular procedure could not correct. The tibial condylar valgus osteotomy (TCVO) represents an intra-articular surgical technique for treating advanced medial knee OA with lateral joint subluxation. Currently, only a few papers with small samples and limited follow-up report the use of TCVO for the treatment of intra-articular deformities. Indications and operative techniques are various and not standardized. After an extensive search of PubMed, Scopus and Cochrane library, the main purpose of this paper is to summarize and discuss the indications, surgical techniques, and outcomes of intra-articular osteotomies while also reporting the preoperative planning and surgical procedure performed at our institution. These characteristics allow earlier weight-bearing and faster complete recovery. TCVO is an effective procedure to correct lower limbs' intra-articular defects from degenerative conditions developmental and post-traumatic deformities. This surgical technique, working at the intra-articular level, leads to some benefits related to restoring joint congruence and stability by realigning the axis of the lower limb and reducing the lateral joint subluxation. Moreover, the improved valgisation and lateralization of the mechanical axis and the limitation of the osteotomy to the medial condyle led to a better load distribution to the not osteotomy-involved compartment.

Protocol for the POMELO (Prevention Of MusclE Loss in Osteoarthritis) randomized pilot feasibility trial

ObjectiveIndividuals with advanced knee osteoarthritis (OA) and a large body size [a body mass index (BMI) ≥35 ​kg/m2] have a higher risk of complications with total knee arthroplasty (TKA), and hence may be ineligible for surgery unless they reduce their BMI. However, pre-TKA weight-loss has not been shown to reduce surgical infection risk and may inadvertently increase risk for muscle loss and development of sarcopenic obesity (low muscle and low strength with higher fat mass). This suggests that a knee OA management approach that doesn't focus on weight change (weight-neutral) may be beneficial. This study examines if a weight-neutral behavioural intervention is feasible and acceptable to participants, and improves muscle mass and physical function in comparison to usual care. DesignThis pilot randomized clinical trial compares a 12-week multimodal intervention [including targeted nutrition, progressive resistance exercise, and arthritis self-management support] to usual care. Co-primary outcomes are feasibility and acceptability, with secondary outcomes of change in lean soft tissue and physical function within and between groups at 3-months and 9-months from baseline. Change in waist circumference, fat mass, blood biomarkers, energy metabolism, OA-related pain and function, health-related quality of life, self-efficacy for arthritis management, and interest in pursuing a TKA within and between groups will be explored. ConclusionThis study will inform future development of more personalized knee OA treatment approaches for adults with larger bodies. Further, this will contribute to effective alternative treatment pathways that reduce inequities in access to OA care for this understudied patient population.

Screening of key pathogenic genes in advanced knee osteoarthritis based on bioinformatics analysis.

BackgroundAt present, the progression mechanism of knee osteoarthritis (KOA) has not been fully elucidated, and there is a clinical need for late KOA-specific diagnostic markers to provide reference for preventive treatment. This study aimed to analyze the sequencing results of early- and late-stage KOA synovial tissue based on the key genes of late-stage KOA in combination with a machine learning algorithm.MethodsThe whole transcriptome sequencing results of synovial tissue from KOA patients (GSE176223 and GSE32317) were downloaded from the gene expression omnibus (GEO) database. Thirty-nine early KOA synovial tissue samples and 31 late KOA synovial tissue samples were included in this study. The diagnostic criteria and baseline data balance of early and late KOA were referred to the data source literature, and the two groups of data had good baseline data balance. R software (V3.5.1) and R packages were used for screening and enrichment analysis of differentially expressed genes (DEGs). The key genes were screened by weighted correlation network analysis (WGCNA) and least absolute shrinkage and selection operator (LASSO) regression analysis. A receiver operating characteristic curve (ROC) curve was used to evaluate the diagnostic efficacy of key genes for advanced KOA.Results A total of 211 DEGs related to knee arthritis were screened out. Compared with synovial tissue of early knee arthritis, 111 genes were upregulated and 100 genes were downregulated in the synovial tissue of late knee arthritis. Sixty-six key genes were screened out through WGCNA and 34 key genes were screened out in the LASSO analysis. The genes obtained by the two algorithms combined with three overlapping genes, namely interleukin- 6 (IL-6), C-X-C chemokine ligand 12 (CXCL12), and macrophage migration inhibitor factor (MIF). The areas under the ROC curves of CXCL12, IL-6, and MIF were 0.96, 0.944, and 0.961, respectively (P<0.001).ConclusionsIL-6, CXCL12, and MIF are the key pathogenic genes of KOA, which have good diagnostic efficacy for advanced KOA.

Simultaneous Femoral Osteotomy and Primary Total Knee Arthroplasty in Patient with Severe Extra-articular Deformity : A Case Report

Correction of an extra-articular deformity of the femur and tibia during total knee arthroplasty (TKA) in advanced knee osteoarthritis (OA) is a technically demanding procedure. The challenge is in the implications of the femoral and tibial realignment osteotomy in both coronal and sagittal planes either as step-by-step or simultaneous procedure. We herein describe an unusual case of knee OA characterized by fixed severe varus knee deformity, tibio-femoral bowing, and lower limb internal rotation. The patient underwent distal femoral osteotomy correction accompanied by TKA to restore mechanical and rotational alignment at the same time. A standard primary posterior stabilized (PS) implant was used. The procedure successfully provided stability, restored alignment and delivered good functional outcome. This case highlights the arthroplasty surgeon’s challenges, especially those who work in limited facilities.

Total Knee Arthroplasty After Genicular Nerve Radiofrequency Ablation: Reduction in Prolonged Opioid Use Without Increased Postsurgical Complications.

Introduction:Genicular nerve radiofrequency ablation (GNRFA) is an increasingly used nonsurgical treatment modality for patients with advanced knee osteoarthritis. Previous studies have demonstrated this to be an effective and safe method to decrease pain and increase functionality in this patient population. The purpose of this study was to compare 2-year postoperative complication rates and rates of prolonged postoperative opioid usage between patients undergoing total knee arthroplasty (TKA) after previous GNRFA and those undergoing TKA alone.Methods:Patients who underwent primary TKA after prior GNRFA (GNRFA-TKA) of the ipsilateral knee were identified in a national all-payer claims database from 2010 to 2019. Univariate and multivariable analyses were conducted comparing those with prior GNRFA and those without. Outcomes of interest included prolonged postoperative opioid usage, 2-year revision rates, and 90-day medical complications. Statistical analysis was conducted using R software provided by the PearlDiver Database.Results:In total, 675 patients in the GNRFA-TKA cohort were compared with a control cohort of 255,351 patients. Genicular nerve radiofrequency ablation-total knee arthroplasty patientshad lower odds of prolonged opioid use postoperatively (OR: 0.478; 95%: 0.409 to 0.559; P < 0.001). No notable difference was observed in the 2-year surgical outcomes between cohorts. Patients in the GNRFA-TKA cohort had lower odds of requiring a blood transfusion and having postoperative anemia, all arrhythmias, and urinary infections compared with primary TKA control patients.Conclusion:Preoperative GNRFA leads to a lower rate of prolonged postoperative opioid use in patients undergoing TKA, without an increased risk of complications. Future prospective studies are needed to validate the findings of this database study.

Effects of total knee arthroplasty on skeletal muscle structure and function at the cellular, organellar, and molecular levels.

Total knee arthroplasty (TKA) is an important treatment option for knee osteoarthritis (OA) that improves self-reported pain and physical function, but objectively measured physical function typically remains reduced for years after surgery due, in part, to precipitous reductions in lower extremity neuromuscular function early after surgery. The present study examined intrinsic skeletal muscle adaptations during the first 5 weeks post-TKA to identify skeletal muscle attributes that may contribute to functional disability. Patients with advanced stage knee OA were evaluated prior to TKA and 5 weeks after surgery. Biopsies of the vastus lateralis were performed to assess muscle fiber size, contractility, and mitochondrial content, along with assessments of whole muscle size and function. TKA was accompanied by marked reductions in whole muscle size and strength. At the fiber (i.e., cellular) level, TKA caused profound muscle atrophy that was approximately twofold higher than that observed at the whole muscle level. TKA markedly reduced muscle fiber force production, contractile velocity, and power production, with force deficits persisting in myosin heavy chain (MHC) II fibers after expression relative to fiber size. Molecular level assessments suggest reduced strongly bound myosin-actin cross bridges and myofilament lattice stiffness as a mechanism underlying reduced force per unit fiber size. Finally, marked reductions in mitochondrial content were apparent and more prominent in the subsarcolemmal compartment. Our study represents the most comprehensive evaluation of skeletal muscle cellular adaptations to TKA and uncovers novel effects of TKA on muscle fiber size and intrinsic contractility early after surgery that may contribute to functional disability.NEW & NOTEWORTHY We report the first evaluation of the effects of total knee arthroplasty (TKA) on skeletal muscle at the cellular and subcellular levels. We found marked effects of TKA to cause skeletal muscle fiber atrophy and contractile dysfunction in older adults, as well as molecular mechanisms underlying impaired contractility. Our results reveal profound effects of TKA on muscle fiber size and intrinsic contractility early after surgery that may contribute to functional disability.

Establishment of a qualified integrated care system after total knee arthroplasty as a role of regional rheumatoid and degenerative arthritis centers

BackgroundThe geriatric population and advanced knee osteoarthritis are rapidly increasing in Korea, and the socioeconomic burden of total knee arthroplasty (TKA) is increasing. This study aimed to analyze the demographic, clinical and socioeconomic characteristics of patients who underwent TKA and to differentiate the factors affecting participation in inpatient-intensive rehabilitation programs after TKA in the Jeju regional rheumatoid and degenerative arthritis center established by the government.MethodsThis retrospective cohort study included 845 patients (735 females; 72.0 ± 5.8 years) diagnosed with primary osteoarthritis (OA) of the knee who underwent elective unilateral primary TKA between January 2013 and June 2016. Demographic, clinical, and socioeconomic characteristics, including age, body mass index, obesity, length of stay, OA severity, underlying disease, education level, occupation, and location of residence were reviewed. Patients were allocated to the TKA-only group (home discharge) and to the TKA + rehab group (participation in post-TKA rehabilitation). The variables were analyzed and compared before and after the establishment of the center and according to participation in intensive rehabilitation.ResultsPatients who underwent TKA were mostly female, in the 60 s, and had a high prevalence of comorbidities and obesity. After the rehabilitation center's establishment, the intensive post-TKA participation increased profoundly from 3% to 59.2%. Participants after the center establishment had lower mean BMI and a higher proportion of K-L grade 4 compared to those before the center establishment. The location of residence was the only factor differentiating the participation in the intensive rehabilitation.ConclusionThe regional rheumatoid and degenerative arthritis center was appropriate to satisfy the high unmet need for participating in the intensive rehabilitation after TKA and to execute the qualified integrated post-TKA care system. Policy support should ensure the early rehabilitation and a qualified integrated care system and prepare for the increased burden of revision. Future longitudinal studies should be conducted to assess the long-term effect of the integrated post-TKA rehabilitation program on functional outcomes and patient survivorship free from revision.

Semiactive robotic-arm system versus patient-specific instrumentation in primary total knee arthroplasty: Efficacy and accuracy

To compare the difference in efficacy and accuracy during total knee arthroplasty (TKA) among robotic-arm system, patient-specific instrumentation (PSI) and conventional TKA (COTKA). Retrospective analysis of 90 advanced knee osteoarthritis (OA) patients in our hospital between June 2019 and December 2020 was conducted. Patients were divided into robotic arm-assisted (RA)TKA (group A), PSITKA (group B) and COTKA (group C), 30 cases in each group. The operation time, intraoperative bleeding, and length of hospital stay were counted. Imaging data of hip-knee-ankle angle (HKA), posterior condylar angle (PCA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), and sagittal tibial component angle (sTCA) were statistically analyzed. The postoperative recovery of the patients was evaluated by Knee Society Score (KSS) and the Western Ontario Mac Master University Index Score (WOMAC). Group A had the least intraoperative bleeding. For operation time, group A was the longest compared with group B and group C (P<0.05), while group B was longer than group C (P<0.05). There was no significant difference in HKA, LDFA, and MPTA among the three groups, and the lower limb alignments were all restored to the neutral position. PCA of group A and B were both smaller than that of group C and closer to 0° (P<0.05), but the difference between group A and B was not statistically significant. The sTCA in group A was significantly better than group B, and group B was significantly better than group C (P<0.05). There were no significant differences in function scores among the three groups. Compared to the PSI and CO, RA is more minimally invasive and more accurate in radiographic results.

Contralateral advanced radiographic knee osteoarthritis predicts radiographic progression and future arthroplasty in ipsilateral knee with early-stage osteoarthritis.

To explore whether the severity of contralateral knee osteoarthritis (OA) is associated with OA progression in ipsilateral knee with early OA. Knees in early OA (Kellgren-Lawrence grade (KLG):1-2) with intact baseline demographic and clinical data were retrieved from OAI database and defined as target knees. The target knees were divided into the exposure group (contralateral knees KLG 3 to 4) and the control group (contralateral knees KLG 0 to 2). Both groups underwent propensity score matching (PSM) concerning demographic data, as well as radiographic and clinical outcomes at the baseline. The primary outcome was the upgrade of KLG in the target knee in the first 12 and 24months. The secondary outcome was the incidence of knee arthroplasty in ipsilateral knee during the first 108months. One thousand seven hundred fifty-two knees were included, with 449 in the exposure cohort and 1276 in the control cohort. Four hundred thirty-four knees in each group were matched after PSM. Target knees in the exposure cohort showed a significantly higher rate of radiographic progression in the first 12months (12.9% vs. 5.1%, P < 0.001) and 24months (19.6% vs. 8.1%, P < 0.001). As for the risk of future arthroplasty, a significant difference was also found between the two groups (7.8% vs. 4.0%, P = 0.02). Kaplan-Meier analysis showed that the 108-month accumulated knee survival rate was significantly lower in the exposure group (P = 0.01). The ipsilateral knee with early-stage OA is prone to have worse early to mid-, and long-term prognosis in the circumstance of contralateral radiographic advanced knee OA. Key Points •Identifying early knee osteoarthritis (OA) with a high risk of radiographic progression and future arthroplasty enables early personalized intervention. •This is a novel study to investigate the relationship between the risk of future arthroplasty and contralateral knee status. •Propensity score matching holds promise to minimize selection bias in observational studies. •Knees with early OA are prone to have a high risk of radiographic progression and future arthroplasty in the circumstance of contralateral advanced knee OA.