Quadriceps muscle weakness is related to increased risk of radiographic knee OA but not its progression in both women and men: the Matsudai Knee Osteoarthritis Survey

A scoping review and evaluation of open-source transtibial amputation musculoskeletal models for female populations

Musculoskeletal modeling is often used to study people with transtibial amputations. Females in this population are of particular interest as they are underrepresented in research, experience unique challenges, and demonstrate gait biomechanics distinct from males. Because generic models often neglect innate variations between populations, it is important to determine whether data used to develop a model are representative of the population studied. The objective of this study was to review and analyze existing transtibial amputation musculoskeletal models, establish a database from the information compiled, and use the database to select the model most relevant for studying female populations. A scoping search was performed and a database was created based on data detailing the eligible models. Models were evaluated through a weighted decision process based on criteria of their representation of females with transtibial amputations, prosthetic functionality, development transparency, overall functionality, and experimental validation methods. The scoping review identified 3 studies, Willson et al., LaPrè et al., and Miller and Esposito. A database detailing these models was established. The Willson model scored highest on all criteria except overall functionality, where the LaPrè model outscored it. Based on the established weightings, the Willson model was classed most appropriate for the stated goals. The created database can be used by other researchers to guide their own modeling studies, irrespective of the population of focus. Of the 3, the Willson model was found most relevant for studying females with transtibial amputations. This model will be used in future work investigating and addressing challenges of females with transtibial amputations.

The Differences in Parameters in Ultrasound Imaging and Biomechanical Properties of the Quadriceps Femoris with Unilateral Knee Osteoarthritis in the Elderly: A Preliminary Observational Study

Purpose

Our study aims to evaluate differences in muscle parameters of the quadriceps muscles in patients with knee osteoarthritis (KOA) in older adults.

Methods

The study included 40 patients diagnosed with unilateral knee osteoarthritis in the KOA group (KG) and 40 asymptomatic elderly individuals in the control group (CG). Muscle ultrasonic mean echo intensity and shear modulus, as well as tone and stiffness of the rectus femoris (RF), vastus medialis (VM), and vastus lateralis (VL) were analyzed. Additionally, clinical correlations were performed.

Results

In the KG group, there were significant differences in echo intensity, shear modulus, and tone between the affected and unaffected sides for RF (p=0.003, 0.019, 0.014), while VM showed significant differences in shear modulus and tone (p=0.006, 0.002). Additionally, VL exhibited significant differences in echo intensity, shear modulus, and stiffness (p=0.007, 0.006, 0.010). Compared to the CG group, the KG group showed significant differences in echo intensity of the affected side RF (p=0.001). VM exhibited statistically significant differences in echo intensity and shear modulus (p < 0.001, p=0.008), while VL showed statistically significant differences in echo intensity, tone, and stiffness (p < 0.001, p=0.028, p < 0.001). The correlation results showed that patients with unilateral KOA, VM, and VL echo intensity were correlated with K-L grade (r = 0.443, p=0.004; r = 0.469, p=0.002). The tone of VL was correlated with VAS and WOMAC (r = 0.327, p=0.039; r = 0.344, p=0.030).

Conclusion

The parameters of the quadriceps femoris muscle exhibit asymmetry between the affected and unaffected sides in patients with unilateral KOA, as well as a difference between the dominant side of healthy older individuals and the affected side of KOA.

Accuracy of a portable lower-limb muscle strength measuring device with a training function

[Purpose] Quadriceps muscle strength is essential for daily living activities. Therefore, we developed a compact and simple lower limb muscle strength measuring device (LocomoScan [LCS]). This study aimed to compare LCS with other instruments to analyze its simplicity, reproducibility, and accuracy. [Participants and Methods] One hundred and four healthy university students (56 males and 48 females) were included in the study. The knee extension force was measured using LCS, and the knee extension torque was measured using other devices (Cybex). In addition, lower leg muscle mass was measured using a body composition meter. The reproducibility of LCS and the correlation between the knee extension torque and lower leg muscle mass were evaluated. [Results] The measurement reproducibility of LCS was significantly higher. The knee extension force confirmed the proportional relative reliability of Cybex with knee extension torque. A relationship between knee extension force and lower limb muscle mass was also observed, indicating that muscle mass cannot be estimated as muscle strength. [Conclusion] The high reproducibility of the knee extension force measurement using LCS demonstrates its potential as a portable alternative instrument for muscle strength measurement in clinical practice. Therefore, LCS device is a simple and effective tool for assessing muscle strength.

Causal relationship between sarcopenia with osteoarthritis and the mediating role of obesity: a univariate, multivariate, two-step Mendelian randomization study

BACKGROUND

Recent genetic evidence supports a causal role for sarcopenia in osteoarthritis, which may be mediated by the occurrence of obesity or changes in circulating inflammatory protein levels. Here, we leveraged publicly available genome-wide association study data to investigate the intrinsic causal relationship between sarcopenia, obesity, circulating inflammatory protein levels, and osteoarthritis.

METHODS

In this study, we used Mendelian randomization analyses to explore the causal relationship between sarcopenia phenotypes (Appendicular lean mass [ALM], Low hand-grip strength [LHG], and usual walking pace [UWP]) and osteoarthritis (Knee osteoarthritis [KOA], and Hip osteoarthritis [HOA]). Univariable Mendelian randomization (UVMR) analyses were performed using the inverse variance weighted (IVW) method, MR-Egger, weighted median method, simple mode, and weighted mode, with the IVW method being the primary analytical technique. Subsequently, the independent causal effects of sarcopenia phenotype on osteoarthritis were investigated using multivariate Mendelian randomization (MVMR) analysis. To further explore the mechanisms involved, obesity and circulating inflammatory proteins were introduced as the mediator variables, and a two-step Mendelian randomization analysis was used to explore the mediating effects of obesity and circulating inflammatory proteins between ALM and KOA as well as the mediating proportions.

RESULTS

UVMR analysis showed a causal relationship between ALM, LHG, UWP and KOA [(OR = 1.151, 95% CI: 1.087-1.218, P = 1.19 × 10-6, PFDR = 7.14 × 10-6) (OR = 1.215, 95% CI: 1.004-1.470; P = 0.046, PFDR = 0.055) (OR = 0.503, 95% CI: 0.292-0.867; P = 0.013, PFDR = 0.027)], and a causal relationship between ALM, UWP and HOA [(OR = 1.181, 95% CI: 1.103-1.265, P = 2.05 × 10-6, PFDR = 6.15 × 10-6) (OR = 0.438, 95% CI: 0.226-0.849, P = 0.014, PFDR = 0.022)]. In the MVMR analyses adjusting for confounders (body mass index, insomnia, sedentary behavior, and bone density), causal relationships were observed between ALM, LHG, UWP and KOA [(ALM: OR = 1.323, 95%CI: 1.224- 1.431, P = 2.07 × 10-12), (LHG: OR = 1.161, 95%CI: 1.044- 1.292, P = 0.006), (UWP: OR = 0.511, 95%CI: 0.290- 0.899, P = 0.020)], and between ALM and HOA (ALM: OR = 1.245, 95%CI: 1.149- 1.348, P = 7.65 × 10-8). In a two-step MR analysis, obesity was identified to play a potential mediating role in ALM and KOA (proportion mediated: 5.9%).

CONCLUSIONS

The results of this study suggest that decreased appendicular lean mass, grip strength, and walking speed increase the risk of KOA and decreased appendicular lean mass increases the risk of HOA in patients with sarcopenia in a European population. Obesity plays a mediator role in the occurrence of KOA due to appendicular lean body mass reduction.

Curcumin regulates autophagy through SIRT3-SOD2-ROS signaling pathway to improve quadriceps femoris muscle atrophy in KOA rat model

Knee osteoarthritis (KOA) usually leads to quadriceps femoris atrophy, which in turn can further aggravate the progression of KOA. Curcumin (CUR) has anti-inflammatory and antioxidant effects and has been shown to be a protective agent for skeletal muscle. CUR has been shown to have a protective effect on skeletal muscle. However, there are no studies related to whether CUR improves KOA-induced quadriceps femoris muscle atrophy. We established a model of KOA in rats. Rats in the experimental group were fed CUR for 5 weeks. Changes in autophagy levels, reactive oxygen species (ROS) levels, and changes in the expression of the Sirutin3 (SIRT3)-superoxide dismutase 2 (SOD2) pathway were detected in the quadriceps femoris muscle of rats. KOA led to quadriceps femoris muscle atrophy, in which autophagy was induced and ROS levels were increased. CUR increased SIRT3 expression, decreased SOD2 acetylation and ROS levels, inhibited the over-activation of autophagy, thereby alleviating quadriceps femoris muscle atrophy and improving KOA. CUR has a protective effect against quadriceps femoris muscle atrophy, and KOA is alleviated after improvement of quadriceps femoris muscle atrophy, with the possible mechanism being the reduction of ROS-induced autophagy via the SIRT3-SOD2 pathway.

Short-Term Impact of Low-Intensity Exercise with Blood Flow Restriction on Mild Knee Osteoarthritis in Older Adults: A Pilot Study

This pilot study aimed to investigate the immediate impact of low-intensity exercises with blood flow restriction (BFR) on older adults with knee osteoarthritis (KOA). Fifteen patients with KOA who were over 50 years old, participated and underwent low-intensity resistance knee exercises at 30% of their one-repetition maximum with BFR three times/week for two weeks. Pre- and post-exercise assessments included pain levels, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores, isokinetic knee strength, lower extremity muscle volume (via leg circumference and muscle thickness), functional performance tests (timed up-and-go [TUG] and sit-to-stand [STS]), skeletal muscle index (SMI) using bioelectrical impedance analysis, and handgrip strength (HGS). Post-exercise, there was a significant reduction in pain. WOMAC scores showed significant improvements across all three domains: pain, stiffness, and physical function. In the TUG and STS tests, completion times were significantly reduced. Thigh and calf circumferences, as well as thigh muscle thickness significantly increased after exercise. Post-exercise SMI and HGS also significantly increased. However, isokinetic knee strength did not show significant changes. In conclusion, low-intensity BFR exercises provide immediate benefits in symptoms and physical performance for patients with KOA, potentially inducing local and systemic muscle mass increase, even after a short-term intervention.

Muscle strength and osteoarthritis of the knee: a systematic review and meta-analysis of longitudinal studies

OBJECTIVE

To evaluate the sex-specific association between low knee extensor and flexor muscle strength and the risk of knee structural worsening.

MATERIALS AND METHODS

Systematic searches in five databases identified longitudinal studies (≥ 1 year follow-up) reporting an association between knee extensor or flexor strength and structural decline in individuals with, or at risk of, knee osteoarthritis. Results were pooled for tibiofemoral and patellofemoral osteoarthritis worsening (and stratified by sex/gender where possible) using a random-effects meta-analysis estimating the risk ratio and 95% confidence interval or a best-evidence synthesis. Risk of bias and overall certainty of evidence were assessed.

RESULTS

Fourteen studies were included with participants (mean age 27-72 years) with osteoarthritis (n = 8), at risk of osteoarthritis (n = 3), or a combination with, or at risk of, osteoarthritis (n = 3). Low knee extensor strength was associated with an increased risk of worsening tibiofemoral (12 studies: RR 1.18, 95% CI 1.04 to 1.35) and patellofemoral osteoarthritis (4 studies: RR 1.62, 95% CI 1.01 to 2.61). Significant associations between low knee extensor strength and worsening tibiofemoral osteoarthritis were observed for women (4 studies: RR 1.25, 95% CI 1.04 to 1.51) but not men (4 studies: RR 1.10, 95% CI 0.87 to 1.39). Low knee flexor strength increased the risk of worsening tibiofemoral osteoarthritis (5 studies: RR 1.16, 95% CI 1.07 to 1.26). Ten studies were high risk of bias, and all estimates were graded as very low certainty of evidence.

CONCLUSION

Low knee extensor and flexor strength increased the risk of worsening tibiofemoral osteoarthritis. Low knee extensor strength increased the risk of worsening patellofemoral osteoarthritis. The relationship between low knee extensor strength and worsening tibiofemoral osteoarthritis may be modified by sex/gender.

Effectiveness of Kinesio taping and conventional physical therapy in the management of knee osteoarthritis: a randomized clinical trial

BACKGROUND

Knee osteoarthritis (OA) is the most common kind of arthritis that occurs due to degeneration of the joint articular cartilage, producing pain, stiffness, and impaired movement. The objective of the study was to evaluate the short-term effectiveness of Kinesio taping (KT) plus conventional physical therapy (CPT) and CPT alone in subjects with knee OA.

MATERIALS AND METHODS

Forty male subjects were divided into two groups at random using a parallel assignment, double-blinded study design, viz., KT with CPT (transcutaneous electrical nerve stimulation and exercise therapy), and CPT alone for the period of 6 weeks of treatment. At baseline, third, and sixth weeks, the following outcome measures were taken, such as pain intensity (NPRS), knee range of motion (goniometry), Western Ontario and McMaster Osteoarthritis Index (WOMAC), and the Time Up and Go (TUG) test.

STATISTICAL ANALYSIS

To reveal the patient's demographic profile concerning the outcome parameters, a descriptive statistic was applied. Furthermore, two-way mixed ANOVA and Tukey HSD post hoc tests were used to analyze within and between-group comparisons in SPSS 20.0.

RESULTS

In both groups, pain and knee flexion were significantly improved during the 6-week period of interventions (p < 0.05). WOMAC and TUG test scores improved only in the KT plus CPT group.

CONCLUSION

KT combined with CPT was found to be more effective than CPT alone in the third and sixth weeks of the treatment. In knee OA, this combination of treatments was found to reduce pain, enhance range of motion, and improve physical functioning.

Favorable Patient-Reported, Clinical, and Functional Outcomes 2 Years After ACL Repair and InternalBrace Augmentation Compared With ACL Reconstruction and Healthy Controls

BACKGROUND

Recently, interest in anterior cruciate ligament (ACL) preservation and repair after proximal ACL tears has been resurrected. Although good clinical outcomes have been reported in the literature with adequate patient selection, to date detailed scientific evidence for the functional benefit of primary ACL repair with ligament augmentation is scarce.

PURPOSE

To compare patient-reported, clinical, and functional outcomes in patients 2 years after ACL repair and InternalBrace augmentation (ACL-IB) with age- and sex-matched patients 2 years after ACL reconstruction (ACL-R) and with matched healthy controls.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

In total, 29 patients 2 years after ACL-IB, 27 sex- and age- matched patients 2 years after ACL-R (hamstring autografts), and 29 matched healthy controls were included. Patient-reported outcomes were assessed using the International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, EQ-5D-5L, Tegner Activity Scale, and Anterior Cruciate Ligament Return to Sports after Injury scale. Surgery time was recorded. For clinical outcomes, range of motion and thigh and shank circumference were measured, and passive anterior translation was determined using the Rolimeter. Isokinetic muscle strength was measured using a Biodex dynamometer. The limb symmetry index (operated/contralateral or nondominant/dominant × 100), side-to-side differences (operated - contralateral, nondominant - dominant), and hamstring-quadriceps ratios were calculated for functional parameters. Failure and reoperation rates were not compared.

RESULTS

Two years after surgery, patients treated with ACL-IB showed good to excellent patient-reported outcomes comparable with those of patients after ACL-R. Surgery time, including concomitant surgeries, was significantly shorter in the ACL-IB group (mean, 81 minutes) compared with the ACL-R group (mean, 97 minutes) (P = .024). Isokinetic muscle strength was comparable between patient groups without significant differences in extensor and flexor strength or in hamstring-quadriceps ratios.

CONCLUSION

These results suggest that ACL-IB achieves comparable patient-reported, clinical, and functional outcomes with ACL-R at 2 years postoperatively and, after careful patient selection, should be considered as a valuable early treatment alternative for proximal ACL tears.

REGISTRATION

NCT04429165 (ClinicalTrials.gov identifier).

Sensory-motor training versus resistance training in the treatment of knee osteoarthritis: A randomized controlled trial

OBJECTIVE

To compare the effectiveness of sensory-motor training and resistance training in patients with knee osteoarthritis.

DESIGN

Randomized controlled trial.

SETTING

Istanbul University, Department of Physiotherapy and Rehabilitation.

SUBJECTS

Forty-eight participants with knee osteoarthritis.

INTERVENTIONS

Following baseline assessment, participants were randomly allocated to sensory-motor training (n  =  24) and resistance training (n = 24). Both groups received training three times a week for 8 weeks.

MAIN MEASURES

The primary outcome measure was the Western Ontario and McMaster Universities Arthritis Index (WOMAC). The secondary outcome measures were pain level, muscle strength, proprioception, range of motion, quality of life, and patient satisfaction with treatment. Patients were assessed before and after four- and eight-week interventions.

RESULTS

There was no significant difference between the groups' total WOMAC scores after four- and eight-week interventions (respectively, p = 0.415, p = 0.828). There was a significant improvement in pain level during movement and in the energy subscale SF-36 for resistance training after the four-week intervention (respectively, p = 0.012, p = 0.007). After the eight-week intervention, a significant difference was noted in favor of resistance training in the secondary outcome measure quality of life (QoL). No significant difference was found in other secondary outcomes.

CONCLUSIONS

At the end of the treatment, it was observed that sensory-motor training had a similar effect in the treatment of knee osteoarthritis symptoms to resistance training. These findings may suggest that sensory-motor training is an effective new method to treat patients with knee osteoarthritis.

LncRNA ZFAS1 protects chondrocytes from IL-1β-induced apoptosis and extracellular matrix degradation via regulating miR-7-5p/FLRT2 axis

BACKGROUND

Increasing evidence suggested that long non-coding RNAs (lncRNAs) played vital roles in osteoarthritis (OA) progression. In this study, we aimed to reveal the protective roles of lncRNA ZFAS1 in osteoarthritis (OA) and further investigated its underlying mechanism.

METHODS

The chondrocytes were stimulated by IL-1β to establish an in vitro OA model. Then, the expression of ZFAS1, miR-7-5p, and FLRT2 in chondrocytes was determined by qRT-PCR. Gain- and loss-of-function assays of ZFAS1, miR-7-5p and FLRT2 were conducted. CCK-8 assay and flow cytometry analysis were performed to detect cell viability and apoptosis rate. The expression levels of cartilage-related proteins, including MMP13, ADAMTS5, Collagen II, and Aggrecan, were measured by western blot analysis. The interaction between ZFAS1 and miR-7-5p, as well as miR-7-5p and FLRT2, was confirmed by dual-luciferase reporter assay and RNA immunoprecipitation assay.

RESULTS

The expression of ZFAS1 and FLRT2 was down-regulated, while the expression of miR-7-5p was up-regulated in chondrocytes exposed to IL-1β. ZFAS1 overexpression promoted cell viability and suppressed apoptosis in IL-1β-treated chondrocytes. Besides, ZFAS1 overexpression suppressed the expression of MMP13 and ADAMTS5, but promoted the expression of Collagen II and Aggrecan to suppress ECM degradation. The mechanistic study showed that ZFAS1 sponged miR-7-5p to regulate FLRT2 expression. Furthermore, the overexpression of miR-7-5p could neutralize the effect of ZFAS1 in IL-1β-treated chondrocytes, and suppression of FLRT2 counteracted the miR-7-5p down-regulation role in IL-1β-treated chondrocytes.

CONCLUSIONS

ZFAS1 could promote cell viability of IL-1β-treated chondrocytes via regulating miR-7-5p/FLRT2 axis. Trial registration Not applicable.

The roles of Runx1 in skeletal development and osteoarthritis: A concise review

Runt-related transcription factor-1 (Runx1) is well known for its functions in hematopoiesis and leukemia but recent research has focused on its role in skeletal development and osteoarthritis (OA). Deficiency of the Runx1 gene is fatal in early embryonic development, and specific knockout of Runx1 in cell lineages of cartilage and bone leads to delayed cartilage formation and impaired bone calcification. Runx1 can regulate genes including collagen type II (Col2a1) and X (Col10a1), SRY-box transcription factor 9 (Sox9), aggrecan (Acan) and matrix metalloproteinase 13 (MMP-13), and the up-regulation of Runx1 improves the homeostasis of the whole joint, even in the pathological state. Moreover, Runx1 is activated as a response to mechanical compression, but impaired in the joint with the pathological progress associated with osteoarthritis. Therefore, interpretation about the role of Runx1 could enlarge our understanding of key marker genes in the skeletal development and an increased understanding of Runx1 could be helpful to identify treatments for osteoarthritis. This review provides the most up-to-date advances in the roles and bio-mechanisms of Runx1 in healthy joints and osteoarthritis from all currently published articles and gives novel insights in therapeutic approaches to OA based on Runx1.

The coronal inclination of the medial tibial plateau affects coronal gait kinematics for varus osteoarthritic knees

PURPOSE

This study aims to (1) measure the kinematics of lower extremity alignment and the bony position relative to the ground during walking, focusing on the coronal plane, and (2) determine the correlation between the kinematics and coronal inclination of the medial tibial plateau (coronal inclination) for healthy and varus knee osteoarthritis (OA).

METHODS

In this study, 43 women (non-OA, 9 knees; early OA, 13 knees; advanced OA, 21 knees; mean age 58 ± 17 years) were examined. The knee phenotypes in varus knee OA were varied. Three-dimensional (3D) knee kinematics were calculated in gait analysis by combining the motion capture system and the 3D lower extremity alignment assessment system via biplanar long-leg X-rays, applying the 3D-2D registration technique. The main parameters were the kinematics of the bony axes relative to the ground in the coronal plane during the stance phase of the gait. The differences in overall kinematics were assessed using repeated measures ANOVA with Tukey's post hoc test. The association between kinematic parameters and coronal inclination was evaluated by multiple linear regression after univariate analysis.

RESULTS

The tibia tilted laterally during the loading response, and a plateau area subsequently appeared until the terminal stance phase, whereas the femur slowly tilted laterally until the terminal stance phase. The dynamic alignment showed a relatively large varus angular change during the loading response in all groups. The trend of motion was similar among all groups (p = n.s.), although to varying degrees. The coronal inclination was the more dominant factor than the Kellgren-Lawrence (K-L) grades (β =  - 0.423, p = 0.005) when the change in dynamic alignment was determined.

CONCLUSIONS

The TAA plateau area after the loading response implies that the tibial articular surface may become horizontal. The femur slowly tilted laterally until the terminal stance phase in response to the tibial motion. Consequently, the dynamic alignment showed a varus angular change, in which coronal MCT was more involved than K-L grades.

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

PURPOSE

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.

METHODS

This study analyzed 879 knees involving 186 males (74 years) and 693 females (74 years). 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.

RESULTS

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.

CONCLUSION

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.

LEVEL OF EVIDENCE

IV.

Environmental Risk Factors for Osteoarthritis: The Impact on Individuals with Knee Joint Injury

Osteoarthritis is a debilitating chronic condition involving joint degeneration, impacting over 300 million people worldwide. This places a high social and economic burden on society. The knee is the most common joint impacted by osteoarthritis. A common cause of osteoarthritis is traumatic joint injury, specifically injury to the anterior cruciate ligament. The purpose of this review is to detail the non-modifiable and modifiable risk factors for osteoarthritis with particular focus on individuals after anterior cruciate ligament injury. After reading this, health care providers will better comprehend the wide variety of factors linked to osteoarthritis.

Strain sonoelastography in asymptomatic individuals and individuals with knee osteoarthritis: an evaluation of quadriceps and patellar tendon

An advanced ultrasound imaging technique, sonoelastography (SE) is used to evaluate tissue elasticity. To determine SE potential to detect pathological-related changes, and characteristics related to tendon pathology we aimed to (1) compare quadriceps and patellar tendon findings in individuals with knee osteoarthritis (KOA) and asymptomatic older adults (AC), and (2) explore associations between SE, participant characteristics (age, BMI, and leg circumference) and KOA status. 84 participants (47; KOA and 37; asymptomatic older adults) underwent SE examination of quadriceps (distal) and patellar (distal, proximal) tendon in a supine position with the knee bent at 30°. Colour score (CS) and Elasticity Ratio (ER) analysis were performed by a blinded experienced operator using Esaote Mylab 70 XVG Ultrasound equipment. Significantly reduced elasticity in the distal quadriceps (median (IQR) 2(2), 3(1), p = 0.033 for KOA and AC, respectively) and proximal patellar (3(1), 3(0), p = 0.001) tendons and more elastic distal patellar (1.50 (0.55), 1.87 (0.72), p = 0.034) tendons were observed in the KOA group. Significant associations) were identified between SE and participant BMI (Rs = − 0.249–0.750, p < 0.05) and leg circumference (Rs = − 0.260–0.903, p < 0.05). Age, BMI and KOA status, were independent explanatory variables of SE CS findings at the distal quadriceps tendon patellar tendon, proximal patellar tendon and distal patellar tendon, explaining 66%, 81% and 64% of variance, respectively. Age, BMI and KOA status were independent explanatory variables of SE ER findings at the distal patellar tendon explaining 19% of variance. Potentially clinically relevant altered tendon stiffness were observed between individuals with KOA and asymptomatic controls. Key KOA risk factors and participant characteristics explained variance in tendon stiffness. Findings provide context for future studies to investigate the potential for targeted SE detected early clinical management based on associated participant characteristics.

The association between diabetes mellitus and functionality in knee osteoarthritis: a cross-sectional study

Objective: The aim of this study was to determine the roles of diabetes mellitus (DM) on quality of life, function of knee, and muscle strength in patients with knee osteoarthritis (OA). Material and Method: This single-center, case-control study prospectively enrolled outpatients with knee OA visiting a physical therapy and rehabilitation clinic. The patients were grouped according to the presence of DM diagnosis. Demographic data, disease duration, and medical treatments of patients were recorded. Clinical parameters, radiographic grading (Kellgren-Lawrence grades), functional scales of the knee and quality of life were evaluated. Results: The study included 82 participants [age: 61.3±6.7 years; female: 76.8%]. The mean Western Ontario and McMaster Universities Osteoarthritis Index of OA patients with (n=37) and without DM (n=45) were 45.79±18.04 vs. 65.94±16.23, respectively (p=0.003). The Hb A1c levels showed a negative correlation with Knee Injury and Osteoarthritis Outcome Score components (pain, quality of life, sports, daily activities, symptom duration) (p

Epidemiology of osteoarthritis

OBJECTIVE

To summarize the current state of the evidence regarding osteoarthritis (OA) prevalence, incidence and risk factors at the person-level and joint-level.

DESIGN

This was a narrative review that took a comprehensive approach regarding inclusion of potential risk factors. The review complements prior reviews of OA epidemiology, with a focus on new research and emerging topics since 2017, as well as seminal studies.

RESULTS

Studies continue to illustrate the high prevalence of OA worldwide, with a greater burden among older individuals, women, some racial and ethnic groups, and individuals with lower socioeconomic status. Modifiable risk factors for OA with the strongest evidence are obesity and joint injury. Topics of high interest or emerging evidence for a potential association with OA risk or progression include specific vitamins and diets, high blood pressure, genetic factors, metformin use, bone mineral density, abnormal joint shape and malalignment, and lower muscle strength/quality. Studies also continue to highlight the heterogenous nature of OA, with strong interest in understanding and defining OA phenotypes.

CONCLUSIONS

OA is an increasingly prevalent condition with worldwide impacts on many health outcomes. The strong evidence for obesity and joint injury as OA risk factors calls for heightened efforts to mitigate these risks at clinical and public health levels. There is also a need for continued research regarding how potential person- and joint-level risk factors may interact to influence the development and progression of OA.

Assessment of central aponeurosis curvature as an index of rectus femoris muscle overstrain in individuals with knee osteoarthritis

BACKGROUND

In medial knee osteoarthritis (knee OA), compensatory overstrain of the rectus femoris (RF) muscle leads to its hypertrophy. We hypothesize that besides hypertrophy of the RF, a prominent flattening of the central aponeurosis (CA) curvature is also indicative of RF. This study aims to evaluate the structural changes in the CA and clarify the conditions associated with RF overstrain in knee OA.

OBJECTIVE

Twenty-three legs of 20 elderly without knee OA (elderly group) and 26 legs of 20 individuals with K-L grade II knee OA (knee OA group) with typical "comma"-shaped CA participated in this study.

METHODS

The knee extension torque (Nm/kg) in the sitting position, the thickness of the RF and vastus intermedius (VI) muscles (VI), and change in CA curvature (%Curvature) were measured at the mid-thigh by ultrasonography.

RESULTS

The knee extension torque was not significantly different between the two groups. Compared to the elderly group, the knee OA group had significantly thicker RF at rest, while the VI thickness during contraction was significantly smaller. The %Curvature was significantly higher in the knee OA group than in the elderly group.

CONCLUSIONS

In the knee OA group, the RF was hypertrophic with a more pronounced CA flattening during muscle contraction, although the other quadriceps muscles were atrophic, suggesting an overstrained RF. Assessing thickness and CA curvature of the RF is, therefore, useful and simple for evaluating overstrain caused by RF compensation.

Effect of low-load resistance training with different degrees of blood flow restriction in patients with knee osteoarthritis: study protocol for a randomized trial

BACKGROUND

Knee osteoarthritis (KOA) is a common degenerative disease that causes pain, functional impairment, and reduced quality of life. Resistance training is considered as an effective approach to reduce the risk of muscle weakness in patients with KOA. Blood flow restriction (BFR) with low-load resistance training has better clinical outcomes than low-load resistance training alone. However, the degree of BFR which works more effectively with low-load resistance training has not been determined. The purpose of this study is to evaluate the effectiveness of different degrees of BFR with low-load resistance training in patients with KOA on pain, self-reported function, physical function performance, muscle strength, muscle thickness, and quality of life.

METHODS

This is a study protocol for a randomized, controlled trial with blinded participants. One hundred individuals will be indiscriminately assigned into the following groups: two training groups with a BFR at 40% and 80% limb occlusion pressure (LOP), a training group without BFR, and a health education group. The three intervention groups will perform strength training for the quadriceps muscles twice a week for 12 weeks, while the health education group will attend sessions once a week for 12 weeks. The primary outcome is pain. The secondary outcomes include self-reported function, physical function performance, muscle strength of the knee extensors, muscle mass of the quadriceps, quality of life, and adverse events. Intention-to-treat analysis will be conducted for individuals who withdraw during the trial.

DISCUSSION

Previous studies have shown that BFR with low-load resistance training is more effective than low-load resistance training alone; however, a high degree of BFR may cause discomfort during training. If a 40% LOP for BFR could produce similar clinical outcomes as an 80% LOP for BFR, resistance training with a low degree of BFR can be chosen for patients with KOA who are unbearable for a high degree of BFR.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2000037859 ( http://www.chictr.org.cn/edit.aspx?pid=59956&htm=4 ). Registered on 2 September 2020.

Efficacy and Safety of Blood Flow Restriction Training in Patients With Knee Osteoarthritis: A Systematic Review and Meta-Analysis

OBJECTIVE

To evaluate the efficacy and safety of blood flow restriction training (BFRT) in the treatment of patients with knee osteoarthritis (OA).

METHOD

Seven electronic databases were searched to identify trials comparing BFRT and conventional resistance training in a population with knee OA. Studies were selected according to the inclusion and exclusion criteria. Standardized mean differences (SMDs) or risk ratios (RRs) with 95% confidence intervals (95% CIs) were calculated to compare outcome measures of the groups. The methodologic quality of selected studies and the quality of evidence were evaluated for included studies.

RESULTS

A total of 5 studies were included in this meta-analysis, with very low to moderate risk of bias. The pooled results showed no significant difference between BFRT and conventional resistance training for knee OA, including pain (SMD -0.04 [95% CI -0.31, 0.24], P = 0.79), physical function performance (SMD 0.12 [95% CI -0.55, 0.78], P = 0.73), self-reported function (SMD 0.14 [95% CI -0.24, 0.52], P = 0.48), and adverse events (RR 0.45 [95% CI 0.20, 1.01], P = 0.05). In subgroup analysis, BFRT had a lower incidence of adverse events when compared with high-load resistance training (HLRT).

CONCLUSION

Data from pooled studies showed that BFRT may not have greater efficacy for treating patients with knee OA, and it is less likely to have a higher risk of adverse events. However, limited evidence supports the idea that BFRT is likely safer than HLRT. More evidence with high quality is needed in further research on efficacy and safety.

Knee extensor muscle weakness is a risk factor for the development of knee osteoarthritis: an updated systematic review and meta-analysis including 46 819 men and women

OBJECTIVE

To update a systematic review on the association between knee extensor muscle weakness and the risk of incident knee osteoarthritis in women and men.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Systematic searches in PubMed, EMBASE, SPORTDiscus, CINAHL, AMED and CENTRAL in May 2021.

ELIGIBLE CRITERIA FOR SELECTING STUDIES

Longitudinal studies with at least 2 years follow-up including baseline measure of knee extensor muscle strength, and follow-up measure of symptomatic or radiographic knee osteoarthritis. Studies including participants with known knee osteoarthritis at baseline were excluded. Risk of bias assessment was conducted using six criteria for study validity and bias. Grading of Recommendations Assessments, Development and Evaluation assessed overall quality of evidence. Meta-analysis estimated the OR for the association between knee extensor muscle weakness and incident knee osteoarthritis.

RESULTS

We included 11 studies with 46 819 participants. Low quality evidence indicated that knee extensor muscle weakness increased the odds of symptomatic knee osteoarthritis in women (OR 1.85, 95% CI 1.29 to 2.64) and in adult men (OR 1.43, 95% CI 1.14 to 1.78), and for radiographic knee osteoarthritis in women: OR 1.43 (95% CI 1.19 to 1.71) and in men: OR 1.39 (95% CI 1.07 to 1.82). No associations were identified for knee injured populations except for radiographic osteoarthritis in men.

DISCUSSION

There is low quality evidence that knee extensor muscle weakness is associated with incident symptomatic and radiographic knee osteoarthritis in women and men. Optimising knee extensor muscle strength may help to prevent knee osteoarthritis.

PROSPERO REGISTRATION NUMBER

CRD42020214976.

Is there a relationship between hand grip strength and knee osteoarthritis in terms of radiological and functional findings in female patients?

Objectives

The aim of this study was to assess the presence of the relationship between hand grip strength (HGS) and radiological and functional signs of knee osteoarthritis (KOA).

Patients and methods

Between March 2019 and January 2020, a total of 64 female patients (mean age: 63.4±8.8 years; range, 50 to 80 years) with bilateral chronic knee pain who were diagnosed with KOA using radiological and clinical findings according to the 2019 American College of Rheumatology guidelines were included in the study. Patient demographics, body mass index (BMI) values, and hand dominance were recorded. The Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Lower Extremity Functional Scale (LEFS) were used for the assessment of KOA functionality. The Kellgren-Lawrence (KL) grading system was used for the radiological assessment of KOA. Electronic dynamometer was used for HGS measurement and values were normalized according to BMI results.

Results

In the assessment of relationship between HGS and functionality of KOA, a negative, moderate correlation was found between the WOMAC and HGS-Dominant (D) (r=0.312, p<0.05) and HGS-Non-Dominant (ND) (r=0.391, p<0.01). In addition, a positive, moderate correlation was found between the LEFS and HGS-D (r=0.344, p<0.01) and HGS-ND (r=0.371, p<0.01). There was a weak, negative correlation between the HGS-ND, KL-D (r=0.256, p<0.05) and KL-ND (r=0.283, p<0.05), while no significant correlation was found between the HGS-D and KL.

Conclusion

Our study results show that HGS-ND is associated with KOA radiologically and functionally. The HGS should be added in the WOMAC and LEFS scales in the functional assessment of KOA and new scales including HGS assessment should be developed.

New evaluation indices for rotational knee angles in standing anteroposterior knee radiographs

BACKGROUND

Identifying the time course of rotational knee alignment is crucial for elucidating the etiology in knee osteoarthritis.

OBJECTIVE

The aim of this study was to propose new rotational indices for calculating the change in relative rotational angles between the femur and tibia in standing anteroposterior (AP) radiographs.

METHODS

Forty healthy elderly volunteers (20 women and 20 men; mean age, 70 ± 6 years) were assessed. The evaluation parameters were as follows: (1) femoral rotational index: the distance between the sphere center of the medial posterior femoral condyle and the lateral edge of the patella, and (2) tibial rotational index: the distance between the medial eminence of the tibia and the lateral edge of the fibula head. The indices were standardized by the diameter of the sphere of the medial posterior femoral condyle. This study (1) identified the relationship between changes in rotational indices and the simulated rotational knee angles in the standing position, (2) proposed a regression equation for the change in relative rotational angles between the femur and tibia in standing AP radiographs, and (3) verified the accuracy of the regression equation.

RESULTS

The rotational indices increased in direct proportion to simulated rotational knee angles (femoral index: r > 0.9,p < 0.0001; tibial index: r > 0.9, p < 0.0001). Based on the results, the regression equation with the accuracy of 0.45 ± 0.26° was determined.

CONCLUSIONS

The proposed regression equations can potentially predict the change in relative rotational angles between the femur and tibia in a pair of standing AP radiographs taken at different dates in longitudinal studies.

Association of isometric quadriceps strength with stride and knee kinematics during gait in community dwelling adults with normal knee or early radiographic knee osteoarthritis

BACKGROUND

Identifying indicators of early knee osteoarthritis is important for preventing the onset and/or progression of the disease. Although low quadriceps strength and changes in stride and knee kinematics during gait have been suggested as possible indicators, their relevance and relationships have not been fully examined. This study aimed to analyze the association of quadriceps strength with stride and knee kinematics during gait in adults with normal knee or early knee osteoarthritis.

METHODS

A total of 881 knees from 474 community dwelling adults (238 males and 236 females) were included. Radiographic images of the knee in standing position were obtained, and grading of knee osteoarthritis was classified. Isometric quadriceps strength was measured using a force detector device. Three-dimensional knee kinematics during gait was obtained by a motion capture system. Sex-based difference of quadriceps strength, stride and knee kinematics during gait was evaluated by multiple comparison among grades by sex and multiple regression of quadriceps strength was analyzed by stride and knee kinematics during gait.

FINDINGS

Stride length and quadriceps strength were significantly reduced with higher grade in both sexes, and changes in knee kinematics during gait differed by sex from early knee osteoarthritis. Quadriceps strength in both sexes was significantly correlated with changes in stride length and knee kinematics during gait.

INTERPRETATION

Improving quadriceps strength in early knee osteoarthritis was related with maintaining gait ability and restraining abnormal knee kinematics during gait. This may help to develop clinical approaches to prevent the onset and/or progression of knee osteoarthritis.

Empirical study of the 30-s chair-stand test as an indicator for musculoskeletal disorder risk of sedentary behaviour in Japanese office workers: a cross-sectional empirical study

Objectives

Sedentary behaviour among office workers and the risk of adverse health outcomes are public health problems. However, risk indicators for these outcomes require invasive biochemical examination. A proactive screening tool using a non-invasive, easy-to-use method is required to assess the risk focused on musculoskeletal health for primary prevention. However, middle-aged adults have insufficient awareness of musculoskeletal disorders. This study examined to determine whether the 30-s chair-stand test (CS-30) can be used as a proactive screening index for musculoskeletal disorder risk of sedentary behaviour in office workers.

Design

Cross-sectional study using self-administered questionnaires and physical measurements.

Setting

Four workplaces located in a metropolitan area of Japan.

Participants

431 Japanese office workers aged 20–64 years. 406 valid sets of results remained (valid response rate: 94.2%).

Primary and secondary outcome measures

Musculoskeletal function was measured using the CS-30, quadriceps muscle strength. Receiver operating characteristic curve analysis was used to determine the sensitivity, specificity and optimal cut-off value for the CS-30. The risk of future incidence of musculoskeletal disorders was calculated using current quadriceps muscle strength.

Results

In total participants, 47.0% were male and the mean sitting time in work duration was 455.6 min/day (SD=111.2 min). The mean lower limb quadriceps muscle strength was 444.8 N (SD=131.3 N). For the optimum cut-off value of 23 on the CS-30 for all participants, sensitivity was 0.809 and specificity was 0.231. For men, the optimum cut-off was 25, with a sensitivity of 0.855 and a specificity 0.172. For women, the optimum cut-off was 21, with a sensitivity of 0.854 and a specificity 0.275.

Conclusions

Sensitivity was high, but specificity was insufficient. The CS-30 may be a potential proactive screening index for musculoskeletal disorder risk of sedentary behaviour, in combination with other indicators.

Comparison of proprioception between osteoarthritic and age-matched unaffected knees: a systematic review and meta-analysis

PURPOSE

Theoretically, proprioceptive acuity could decrease in patients with knee osteoarthritis. However, there have been conflicting results in terms of proprioceptive deficit in osteoarthritic knees. The purpose of this systematic review and meta-analysis was to compare knee proprioception between osteoarthritic and healthy control knees.

METHODS

Studies comparing proprioception in osteoarthritic and healthy knees of age-matched control group using thresholds to detect passive motion (TTDPM) or joint position sense (JPS) tests were identified. JPS was assessed by measuring the reproduction of passive positioning (RPP) or active positioning (RAP) of the knees.

RESULTS

Seventeen studies were finally included in this meta-analysis. The pooled results of the analyses of the TTDPM for both 30° and 45° knee flexion showed that the mean angle of error was 0.83° greater (95% confidence interval: 0.44 to 1.23°; p < 0.001) in the osteoarthritic knees than in control knees. The pooled data of the RAP and RPP also showed that the mean angle of error was 1.89° greater in the osteoarthritic knees than in the control group. The mean difference in the angle of error between the osteoarthritic knees and control group was 1.06° greater in the JPS test than in the TTDPM (p < 0.001).

CONCLUSION

The knee proprioceptive acuity of the patients with knee osteoarthritis was poorer than that of the patients with unaffected knees in the age-matched control group both in terms of the TTDPM and JPS; clinical relevance of these deficits needs to be clarified in further studies.

LEVEL OF EVIDENCE

Meta-analysis, Level II.

Meta-analysis on the association between knee extensor strength and structural changes of knee osteoarthritis

This study aimed to perform a meta-analysis to evaluate whether knee extensor (KE) strength weakness was associated with increased structural worsening in knee osteoarthritis (KOA) including joint space narrowing (JSN) and cartilage loss. PubMed, Embase, Scopus, ScienceDirect, Web of Science, and Cochrane library were searched from their inception to May 2020, to identify eligible studies. Odds ratios (ORs) accompanied by 95% confidence intervals (CIs) were calculated for the relationship between KE strength and outcomes. Totally eleven longitudinal studies were included. The pooled crude OR indicated no significant association between KE strength weakness and KOA progression of JSN (OR: 1.13, 95% CI: 0.90, 1.42), and this result duplicated after confounders were adjusted (OR: 1.10, 95% CI: 0.87, 1.39). Subgroup analysis showed the association remained non-significant in sex-specific outcomes and subsets of neutral and malaligned knees, but there was a trend toward increased risk of JSN progression in female knees with low strength (OR: 1.24, 95% CI: 0.87, 1.76, I² = 82%). The pooled crude OR showed that KE strength weakness was associated with increased risk of cartilage loss (OR:1.43, 95% CI: 1.05, 1.95). After adjustment, we found a non-significant trend that low KE strength could increase the risk of cartilage loss (OR: 1.25, 95% CI: 0.95, 1.64), and this trend was separately observed in tibiofemoral or patellofemoral compartments. This meta-analysis suggested that KE strength weakness was not significantly associated with an increased risk of radiographic structural KOA progression in patients with KOA or known risk factors for KOA. However, there was a trend that women with weaker KE strength displayed a higher risk of JSN worsening and that KE strength weakness had an association with an increased risk of cartilage damage. Key points • Knee extensor strength weakness is not significantly associated with an increased risk of radiographic structural KOA progression in patients with or at risk of knee osteoarthritis. • There is a non-significant trend toward an increased risk of JSN progression in female knees with low knee extensor strength. • There is a trend that low KE strength can increase the risk of cartilage loss no matter in tibiofemoral or patellofemoral compartments, but it's not significant.

LncRNA HOTTIP leads to osteoarthritis progression via regulating miR-663a/ Fyn-related kinase axis

BACKGROUND

Long non-coding RNA (lncRNA) has been implicated in the progression of osteoarthritis (OA). This study was aimed to explore the role and molecular mechanism of lncRNA HOXA terminal transcriptional RNA (HOTTIP) in the development of OA.

METHODS

The expression of HOTTIP, miR-663a and Fyn-related kinase (FRK) in the OA articular cartilage and OA chondrocyte model induced by IL-1β was determined by qRT-PCR. CCK-8, colony formation and flow cytometry were used to determine the cell proliferation and apoptosis of OA chondrocytes. The specific molecular mechanism of HOTTIP in OA chondrocytes was determined by dual luciferase reporter assay, qRT-PCR, western blotting and RNA pull-down.

RESULTS

The expression of HOTTIP and FRK were up-regulated, while miR-663a was down-regulated in OA cartilage tissues. Knockdown of HOTTIP decreased the proliferation and induced the apoptosis of OA cartilage model cells, while overexpression of HOTTIP increased the proliferation and reduced the apoptosis of OA cartilage model cells. Moreover, HOTTIP could bind to miR-663a as competitive endogenous RNA. Inhibition of miR-663a expression could alleviate the effect of HOTTIP knockdown on the proliferation and apoptosis of OA cartilage model cells. Furthermore, FRK was found to be a direct target of miR-663a, which could markedly down-regulate the expression of FRK in OA chondrocytes, while HOTTIP could remarkably up-regulate the expression of FRK. In addition, miR-663a inhibition increased the proliferation and reduced the apoptosis of OA cells, while FRK knockdown reversed the effect of miR-663a inhibition on the proliferation and apoptosis of OA cells. Meanwhile, overexpression of miR-663a decreased the proliferation and induced the apoptosis of OA cells, while overexpression of FRK reversed the effect of miR-663a overexpression on the proliferation and apoptosis of OA cells.

CONCLUSION

HOTTIP was involved in the proliferation and apoptosis of OA chondrocytes via miR-663a/ FRK axis, and HOTTIP/miR-663a/FRK might be a potential target for the treatment of OA.

Chondroprotective Effects of Combination Therapy of Acupotomy and Human Adipose Mesenchymal Stem Cells in Knee Osteoarthritis Rabbits via the GSK3β-Cyclin D1-CDK4/CDK6 Signaling Pathway

Adipose-derived stem cells (ASCs) are highly chondrogenic and can be used to treat knee osteoarthritis (KOA) by alleviating cartilage defects. Acupotomy, a biomechanical therapy guided by traditional Chinese medicine theory, alleviates cartilage degradation and is widely used in the clinic to treat KOA by correcting abnormal mechanics. However, whether combining acupotomy with ASCs will reverse cartilage degeneration by promoting chondrocyte proliferation in KOA rabbits is unknown. The present study aimed to investigate the effects of combination therapy of acupotomy and ASCs on chondrocyte proliferation and to determine the underlying mechanism in rabbits with KOA induced by knee joint immobilization for 6 weeks. After KOA modeling, five groups of rabbits (acupotomy, ASCs, acupotomy + ASCs, model and control groups) received the indicated intervention for 4 weeks. The combination therapy significantly restored the KOA-induced decrease in passive range of motion (PROM) in the knee joint and reduced the elevated serum level of cartilage oligomeric matrix protein (COMP), a marker for cartilage degeneration. Furthermore, magnetic resonance imaging (MRI) and scanning electron microscopy (SEM) images showed that the combination therapy inhibited cartilage injury. The combination therapy also significantly blocked increases in the mRNA and protein expression of glycogen synthase kinase-3β (GSK3β) and decreases in the mRNA and protein expression of cyclin D1/CDK4 and cyclin D1/CDK6 in cartilage. These findings indicated that the combination therapy mitigated knee joint immobility, promoted chondrocyte proliferation and alleviated cartilage degeneration in KOA rabbits, and these effects may be mediated by specifically regulating the GSK3β-cyclin D1-CDK4/CDK6 pathway.

Cortical thickness of the tibial diaphysis reveals age- and sex-related characteristics between non-obese healthy young and elderly subjects depending on the tibial regions

PURPOSE

This study aimed to evaluate the age- and sex-related characteristics in cortical thickness of the tibial diaphysis between non-obese healthy young and elderly subjects as reference data.

METHODS

The study investigated 31 young subjects (12 men and 19 women; mean age, 25 ± 8 years) and 54 elderly subjects (29 men and 25 women; mean age, 70 ± 6 years). Three-dimensional estimated cortical thickness of the tibial diaphysis was automatically calculated for 5000-9000 measurement points using the high-resolution cortical thickness measurement from clinical computed tomography data. In 12 assessment regions created by combining three heights (proximal, central, and distal diaphysis) and four areas of the axial plane at 90° (medial, anterior, lateral, and posterior areas) in the tibial coordinate system, the standardized thickness was assessed using the tibial length.

RESULTS

As structural characteristics, there were no differences in the medial and lateral thicknesses, while the anterior thickness was greater than the posterior thickness in all groups. The sex-related difference was not shown. As an age-related difference, elderly subjects showed greater or lesser cortical thickness than the young subjects, depending on the regions of the tibia.

CONCLUSIONS

Cortical thickness was different depending on sex, age, and regions in the tibia. The results of this study are of clinical relevance as reference points to clarify the causes of various pathological conditions for diseases.

LEVEL OF EVIDENCE

Level 3.

Michigan Initiative for Anterior Cruciate Ligament Rehabilitation (MiACLR): A Protocol for a Randomized Clinical Trial

OBJECTIVE

Restoring quadriceps muscle strength following anterior cruciate ligament reconstruction (ACLR) may prevent the posttraumatic osteoarthritis that affects over 50% of knees with ACLR. However, a fundamental gap exists in our understanding of how to maximize muscle strength through rehabilitation. Neurological deficits and muscle atrophy are 2 of the leading mechanisms of muscle weakness after ACLR. High-intensity neuromuscular electrical stimulation (NMES) and eccentric exercise (ECC) have been shown to independently target these mechanisms. If delivered in succession, NMES and then ECC may be able to significantly improve strength recovery. The objectives of this study were to evaluate the ability of NMES combined with ECC to restore quadriceps strength and biomechanical symmetry and maintain cartilage health at 9 and 18 months after ACLR.

METHODS

This study is a randomized, double-blind, placebo-controlled, single-center clinical trial conducted at the University of Michigan. A total of 112 participants between the ages of 14 and 45 years and with an anterior cruciate ligament rupture will be included. Participants will be randomly assigned 1:1 to NMES combined with ECC or NMES placebo combined with ECC placebo. NMES or NMES placebo will be delivered 2 times per week for 8 weeks beginning 10 to 14 days postoperatively and will be directly followed by 8 weeks of ECC or ECC placebo delivered 2 times per week. The co-primary endpoints are change from baseline to 9 months and change from baseline to 18 months after ACLR in isokinetic quadriceps strength symmetry. Secondary outcome measures include isometric quadriceps strength, quadriceps activation, quadriceps muscle morphology (cross-sectional area), knee biomechanics (sagittal plane knee angles and moments), indexes of patient-reported function, and cartilage health (T1ρ and T2 relaxation time mapping on magnetic resonance imaging).

IMPACT

The findings from this study might identify an intervention capable of targeting the lingering quadriceps weakness after ACLR and in turn prevent deterioration in cartilage health after ACLR, thereby potentially improving function in this patient population.

Comparison of the added effects of kinesio taping and extracorporeal shockwave therapy to exercise alone in knee osteoarthritis

INTRODUCTION

Pain and functional limitations affect quality of life of patients with knee osteoarthritis (OA).

PURPOSE

The purpose of this study was to compare the effects of two different applications (Kinesio taping; KT and Extracorporeal Shock Wave Therapy; ESWT) added to an home-exercise program on pain, strength and function in patients with knee OA.

METHODS

Sixty voluntary female subjects were randomly assigned into groups of; KT (n = 22), ESWT (n = 18) and control (CON) (n = 20) respectively. KT and ESWT were applied for 6 weeks and all the groups were taken home exercise program during 12 weeks in all groups. The outcome measures were; Visual Analog Scale for pain (during squat, rest and sleep), Isokinetic strength for quadriceps and hamstring strength, 'The Knee Injury and Osteoarthritis Outcome Survey', Timed Up & Go and 10 m Walk tests for function. The assessments were carried out at baseline, 6th and 12th weeks.

RESULTS

The mean age was 58.8 ± 6.2 years. Significant improvements were observed in all groups in all tests (p < .05). There was no difference found between groups (p > .05) except pain levels during sleep. CON group showed significant reduction in pain during sleep compared to ESWT group (p < .05).

CONCLUSION

KT and ESWT have similar effects in terms of decreasing pain, improving knee strength and function in patients with knee OA. However it can be said that if a well-designed home exercise program were done by the patients correctly and regularly then it will be the best treatment option for patients with knee OA.

Knee Osteoarthritis Grade does not Correlate with Quadriceps Muscle Strength or Bone Properties of the Calcaneus in Men Aged 80 Years or More who Can Walk independently

Purpose: Muscle weakness and bone deterioration in the elderly are related to falls and fractures, resulting in decreased mobility. Knee osteoarthritis also may contribute to falls and fractures and thereby affect mortality rates. The Kellgren–Lawrence (KL) classification is widely used in the radiographic evaluation of knee osteoarthritis. Aims: This study aimed to evaluate the quadriceps strength and bone properties of the calcaneus for each KL grade, and to clarify the impact of knee osteoarthritis grade on quadriceps strength and bone properties. Methods: This prospective cross-sectional study included data on 108 male patients (213 knees), aged ≥80 years, who could walk independently. A handheld dynamometer was used to measure quadriceps strength. Bone properties were evaluated using broadband ultrasound attenuation with a portable bone densitometer. Weight-bearing standing knee radiographs were evaluated using KL classification. Quadriceps strength and bone properties were evaluated for each KL grade and the correlations between the grade and quadriceps strength and bone properties were assessed simultaneously. Results: The numbers of participants in KL grades I–IV were 46, 102, 45, and 20, respectively. There were no differences among grades for either quadriceps strength or bone properties. Conclusions: Participants exhibited good quadriceps strength and bone properties regardless of their KL grade. Relatively high mechanical loading of muscle and bone incurred while walking independently, likely explaining this result. Clinically, this study demonstrated the absence of correlations between KL grade and quadriceps strength and bone properties, as was previously reported in studies showing the absence of a correlation between KL grade and pain.

Early knee osteoarthritis prevalence is highest among middle-aged adult females with obesity based on new set of diagnostic criteria from a large sample cohort study in the Japanese general population

PURPOSE

A few new criteria for early detection and prevention of early knee osteoarthritis (EKOA) have been proposed. However, its prevalence, risk factors, relationship with function and prognosis have not been clarified. The purpose of this study was to investigate the prevalence of EKOA and its risk factors in the Japanese general population.

METHODS

A total of 1104 volunteers (443 males, 661 females) who participated in the Iwaki cohort study in Japan were enrolled in this cross-sectional study. Their bilateral weight-bearing anterior-posterior knee radiographs were classified by Kellgren-Lawrence (KL) grade. EKOA (KL grade 0/1) was defined according to the following criteria: knee injury and osteoarthritis outcome score < 85%, joint line tenderness, and crepitus and its prevalence among age-sex groups was calculated. Logistic regression analyses were performed to determine the risk factors for EKOA.

RESULTS

Eight hundred and twenty-two participants had KL grade 0/1, and the EKOA prevalence was 9.5% in males and 15.0% in females (p = 0.011). The prevalence of EKOA increased with age. The highest prevalence was noted in females aged 50-59 years. Logistic regression analysis showed that the risk factors for EKOA were age (p < 0.001, odds ratio (OR) 1.1), female sex (p = 0.002, OR 2.5), high body mass index (p < 0.001, OR 1.2), and history of knee injury (p < 0.001, OR 21.7).

CONCLUSIONS

The highest EKOA prevalence was observed in middle adult females (50-59 years old). The risk factors for EKOA were female sex, ageing, obesity and knee injury history, which were extremely similar to those of definitive knee osteoarthritis.

LEVEL OF EVIDENCE

Level I in diagnostic studies-investigating a diagnostic test.

Jumping Joints: The Complex Relationship Between Osteoarthritis and Jumping Mechanography

We investigated the relationship between lower limb osteoarthritis (OA) and muscle strength and power (assessed by jumping mechanography) in UK community-dwelling older adults. We recruited 249 older adults (144 males, 105 females). OA was assessed clinically at the knee according to ACR criteria and radiographically, at the knee and hip, using Kellgren and Lawrence grading. Two-footed jumping tests were performed using a Leonardo Mechanography Ground Reaction Force Platform to assess maximum muscle force, power and Esslinger Fitness Index. Linear regression was used to assess the relationship between OA and jumping outcomes. Results are presented as β (95% confidence interval). The mean age of participants was 75.2 years (SD 2.6). Males had a significantly higher maximum relative power during lift off (mean 25.7 W/kg vs. 19.9 W/kg) and maximum total force during lift off (mean 21.0 N/kg vs. 19.1 N/kg) than females. In adjusted models, we found significant associations in males between clinical knee OA and maximum relative power [- 6.00 (CI - 9.10, - 2.94)] and Esslinger Fitness Index [- 19.3 (- 29.0, - 9.7)]. In females, radiographic knee OA was associated with total maximum power [- 2.0 (- 3.9, - 0.1)] and Esslinger Fitness Index [- 8.2 (- 15.9, - 0.4)]. No significant associations were observed for maximum total force. We observed significant negative associations between maximum relative power and Esslinger Fitness Index and clinical knee OA in males and radiographic knee OA in females. We have used novel methodology to demonstrate relationships between muscle function and OA in older adults.

Effect on inclined medial proximal tibial articulation for varus alignment in advanced knee osteoarthritis

BACKGROUND

The inclination of the medial compartment of the proximal tibia (MCT) is assumed to be a critical factor for varus alignment in advanced knee osteoarthritis (OA). This study was aimed at investigating; (1) whether the inclination of MCT is aligned parallel to the ground under weight-bearing (WB) conditions; (2) whether this is associated with the change in alignment and the relative position between the bones; and (3) whether the tibia or femur mainly contributes to the changes.

METHODS

We examined 102 knees (84 women, 18 men; mean 75 years). A three-dimensional (3D) assessment system was applied on biplanar whole lower extremity radiographies using 3D-to-2D image registration technique. The evaluation parameters were 1) MCT angle, 2) femorotibial angle (FTA), 3) medial-lateral femoral location to the tibia (M-L femoral location), 4) WB line passing point, and 5) tibial position to WB line (tibial position) and 6) femoral postion to WB line (femoral position). Each parameter was evaluated in non-WB and WB conditions, and the differences (Δ-parameters).

RESULTS

MCT angle in the world coordinate system was larger than that in the tibial coordinate system (p <  0.0001). ΔMCT angle was correlated with ΔFTA (p = 0.002) and ΔM-L femoral location (p = 0.004). The tibial position was the more dominant factor for ΔMCT angle (p = 0.001), ΔFTA (p <  0.0001), and ΔWB line passing point (p <  0.0001) .

CONCLUSIONS

The inclination in MCT was aligned parallel to the ground under WB conditions (tibial parallel phenomenon). The parallel phenomenon was associated with the change of alignment and the relative position between the bones in the coronal plane. These phenomena were produced mainly by the tibia, not the femur.

LEVEL OF EVIDENCE

Level IV.

Contribution of sex and body constitution to three-dimensional lower extremity alignment for healthy, elderly, non-obese humans in a Japanese population

BACKGROUND

Humans support their bodies exclusively by vertical balance in bipedal locomotion, and the body, especially the lower extremity, generally changes with age. Sex and body constitution are assumed to be associated with lower extremity alignment, but this association remains to be elucidated. This study sought to clarify this association in healthy, elderly, non-obese humans in a Japanese population.

METHODS

The present study investigated 55 healthy volunteers (mean age: 70 ± 6 years). A 3D extremity alignment system was applied under weight-bearing conditions on biplane long lower extremities X-rays using a 3D-to-2D image registration technique. The evaluation parameters included 3D hip-knee-ankle angle (3DHKA) alignment in the coronal (coronal alignment) and sagittal planes (sagittal alignment) and rotational alignment between the femur and tibia. The influences of sex and body constitution on all the alignment were analyzed.

RESULTS

Multiple linear regression analysis with the dependent variable of each alignment showed that sex was the dominant factor for coronal and rotational alignment (coronal: p <  0.01; rotational: p <  0.01), and body weight was the dominant factor for sagittal alignment (p <  0.01).

CONCLUSIONS

The association of sex with coronal and rotational alignment and of body constitution with sagittal alignment were proved in healthy, elderly, non-obese humans in a Japanese population. This finding can lead to further understanding of the etiology of many diseases and age-related changes.