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Background and study aim: Isometric strength exercises engage the intricate knee joint, including the femur, tibia, and patella, along with multiple muscles and ligaments, aiding in the rehabilitation of knee injuries while supporting movement and injury prevention. The specific objective of this research is to investigate the effectiveness of isometric strength exercises in rehabilitating the knee injuries among football players, assessing their impact on recovery and performance. Material and methods: Thirty male ACL Knee injured football players were randomly assigned to isometric strength exercise group (ISEG) (N=15) (Age; 20±1.9, Height;171±4.5, Weight; 60±6.0) and control group (Age;21±1.3, Height;173±4.4, Weight; 63±8.2) and their age ranged between 18 and 23. Subjects were randomly selected from various football academies in Coimbatore, Tamil Nadu, India. Thirty subjects who will diagnosed by a physiotherapist and help of orthopaedician as having knee injuries in football players and who showed a typical restriction of Range of motion (ROM). Fifteen subjects underwent rehabilitation (Isometric Strength exercise Group) and the other 15 underwent cryotreatment (Control Group). Analysis was based on the active and passive flexion Range of motion (ROM) were measured by kinovea-0.9.5 software. Means and standard deviations (±) described all data, with Shapiro-Wilk tests checking for normality (p< 0.05). A dependent 't' test determined significant mean differences between experimental and control groups (p < 0.05). Results: The participants who underwent a regimen of Isometric strengthening exercises exhibited notable enhancements in their range of motion (ROM), highlighting the effectiveness of this comprehensive approach significantly improved in active and passive flexion Range of motion (p < 0.05). Conclusion: Isometric strength exercises demonstrate promise in enhancing knee rehabilitation outcomes among football players, warranting further exploration and implementation compared to control group.

Background/Objectives: Evaluations allowing patients to return to sport (RTS) after anterior cruciate ligament reconstruction (ACLR) should be multimodal, including a psychological evaluation. The goal of this study was to determine if there is a correlation between the ACL–return to sport after injury (ACL-RSI) score at 6 months post-ACLR and mid-term functional results. Methods: A total of 498 patients were assessed 6 months after primary ACLR using a composite test including isokinetics, hops, and ACL-RSI. A minimum of 3 years of follow-up was necessary. At the last follow-up, each patient completed clinical and functional evaluations, including the subjective International Knee Documentation Committee (IKDC) score, Tegner Activity Scale, Self Knee Value (SKV), and ACL-RSI score. The results were compared overall and item by item. Results: At the last follow-up, the mean SKV, Tegner, IKDC, and ACL-RSI scores were 86.8 ± 14.3%, 6 ± 2.1, 77 ± 11.9%, and 68.8 ± 25.7%, respectively. A significant correlation existed between the 6-month ACL-RSI score and each functional test (respectively, ρ = 0.189 p < 0.001; ρ = 0.174 p < 0.001; ρ = 0.237 p < 0.001). The ACL-RSI score was significantly higher than at 6 months after surgery (p < 0.001). Over half (59.2%) of the cohort returned to an equal or greater level of activity, and there was a significant correlation between the 6-month ACL-RSI score and post-surgery level of activity. Conclusions: Patients with better ACL-RSI scores at 6 months post-ACLR have better functional results in the medium term and are more likely to RTS. Our results show a correlation between psychological factors at 6 months, measured through the ACL-RSI score, and activity level at mid-term follow-up. This study underlines the relationship between RTS and psychological effects, and the importance of ACLR rehabilitation to focus on decreasing apprehension and fear. [ABSTRACT FROM AUTHOR]

ObjectiveIn order to address the issues of inconvenience, high medical costs, and lack of universality associated with traditional knee rehabilitation equipment, a portable intelligent wheelchair for knee rehabilitation was designed in this study. MethodsBased on the analysis of the knee joint’s structure and rehabilitation mechanisms, an electric pushrod-driven rehabilitation institution was developed. A multi-functional module was designed with a modular approach, and the control of the wheelchair body and each functional module was implemented using an STM32 single-chip microcomputer. A three-dimensional model was established using SolidWorks software. In conjunction with Adams and Ansys simulation software, kinematic and static analyses were conducted on the knee joint rehabilitation institution and its core components. A prototype was constructed to verify the equipment’s actual performance. ResultsAccording to the prototype testing, the actual range of motion for the knee joint swing rod is 15.1°~88.9°, the angular speed of the swing rod ranges from −7.9 to 8.1°/s, the angular acceleration of the swing rod varies from −4.2 to 1.6°/s², the thrust range of the electric pushrod is −82.6 to 153.1 N, and the maximum displacement of the load pedal is approximately 1.7 mm, with the leg support exhibiting a maximum deformation of about 1.5 mm. ConclusionThe intelligent knee joint rehabilitation wheelchair meets the designed functions and its actual performance aligns with the design criteria, thus validating the rationality and feasibility of the structural design.

Knee osteoarthritis is among the most prevalent chronic diseases. Total knee arthroplasty is a common solution that effectively addresses the continued structural degeneration of the articular cartilage. However, effective physical therapy is critical for recovery. Despite participating in physical therapy, many patients fail to recover. This study investigated the potential efficacy of a behaviorally informed approach to surface electromyographic biofeedback following total knee arthroplasty relative to the clinical standard, neuromuscular electrical stimulation. The surface electromyographic biofeedback procedure incorporated improved techniques for establishing a baseline and individualized and adjusting criteria for feedback. The findings suggest some advantages for surface electromyographic biofeedback over neuromuscular electrical stimulation in quadriceps strength, range of motion, functional recovery, and quality of life. Behaviorally informed surface electromyographic biofeedback holds promise for total knee arthroplasty recovery and these data suggest considerable room for collaboration between behavior analysts and physical therapists. [ABSTRACT FROM AUTHOR]

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Background and study aim. Isometric strength exercises engage the intricate knee joint, including the femur, tibia, and patella, along with multiple muscles and ligaments, aiding in the rehabilitation of knee injuries while supporting movement and injury prevention. The specific objective of this research is to investigate the effectiveness of isometric strength exercises in rehabilitating the knee injuries among football players, assessing their impact on recovery and performance. Material and methods. Thirty male ACL Knee injured football players were randomly assigned to isometric strength exercise group (ISEG) (N=15) (Age; 20±1.9, Height;171±4.5, Weight; 60±6.0) and control group (Age;21±1.3, Height;173±4.4, Weight; 63±8.2) and their age ranged between 18 and 23. Subjects were randomly selected from various football academies in Coimbatore, Tamil Nadu, India. Thirty subjects who will diagnosed by a physiotherapist and help of orthopaedician as having knee injuries in football players and who showed a typical restriction of Range of motion (ROM). Fifteen subjects underwent rehabilitation (Isometric Strength exercise Group) and the other 15 underwent cryotreatment (Control Group). Analysis was based on the active and passive flexion Range of motion (ROM) were measured by kinovea-0.9.5 software. Means and standard deviations (±) described all data, with Shapiro-Wilk tests checking for normality (p<0.05). A dependent 't' test determined significant mean differences between experimental and control groups (p<0.05). Results. The participants who underwent a regimen of Isometric strengthening exercises exhibited notable enhancements in their range of motion (ROM), highlighting the effectiveness of this comprehensive approach significantly improved in active and passive flexion Range of motion (p < 0.05). Conclusion. Isometric strength exercises demonstrate promise in enhancing knee rehabilitation outcomes among football players, warranting further exploration and implementation compared to control group. [ABSTRACT FROM AUTHOR]

Contemporary total knee arthroplasty patients have increased expectations of returning to predisease function, including sexual activity (SA). The purpose of this study was to determine whether patients using a digital care management platform (DCMP) were more likely to have a higher rate and frequency of return to SA. We conducted an exploratory analysis of a prospective, multicenter, randomized controlled trial that enrolled patients undergoing total knee arthroplasty. A total of 304 patients were randomized to a DCMP (n = 119) providing preoperative and postoperative education regarding return to SA or standard postoperative care (control group; n = 185). Return to SA, assessed via questionnaire, patient-reported outcome measures, Timed Up and Go test, single leg stance, active range of motion and need for manipulation under anesthesia were assessed at 90 days postoperatively. More patients in the DCMP group returned to SA compared to control at 90 days (58.4 versus 39.6%, P =.018); however, the control group resumed SA sooner (33.1 versus 42.0 days, P =.023). Patients who returned to SA were younger (61.6 versus 65.9 year), more often men (56 versus 35%) (P <.001), higher performing on the Timed Up and Go and single leg stance tests (P <.001), and had greater active range of motion (P =.007). There were no differences in patient-reported outcome measures or need for manipulation under anesthesia between patients that returned to SA and those who did not. More patients using a DCMP resumed SA at 90 days; however, patients in the control group returned to SA sooner. Those who returned to SA were younger, possessed greater physical function, and were more often men. [ABSTRACT FROM AUTHOR]

The menisci increase the contact area of load bearing in the knee and thus disperse the mechanical stress via their circumferential tensile fibers. Traumatic meniscus injuries cause mechanical symptoms in the knee, and are more prevalent amongst younger, more active patients, compared to degenerative tears amongst the elderly population. Traumatic meniscus tears typically result from the load-and-shear mechanism in the knee joint. The treatment depends on the size, location, and pattern of the tear. For non-repairable tears, partial or total meniscal resection decreases its tensile stress and increases joint contact stress, thus potentiating the risk of arthritis. A longitudinal vertical tear pattern at the peripheral third red-red zone leads to higher healing potential after repair. The postoperative rehabilitation protocols after repair range from immediate weight-bearing with no range of motion restrictions to non-weight bearing and delayed mobilization for weeks. Pediatric and adolescent patients may require special considerations due to their activity levels, or distinct pathologies such as a discoid meniscus. Further biomechanical and biologic evidence is needed to guide surgical management, postoperative rehabilitation protocols, and future technology applications for traumatic meniscus injuries.

The menisci increase the contact area of load bearing in the knee and thus disperse the mechanical stress via their circumferential tensile fibers. Traumatic meniscus injuries cause mechanical symptoms in the knee, and are more prevalent amongst younger, more active patients, compared to degenerative tears amongst the elderly population. Traumatic meniscus tears typically result from the load-and-shear mechanism in the knee joint. The treatment depends on the size, location, and pattern of the tear. For non-repairable tears, partial or total meniscal resection decreases its tensile stress and increases joint contact stress, thus potentiating the risk of arthritis. A longitudinal vertical tear pattern at the peripheral third red-red zone leads to higher healing potential after repair. The postoperative rehabilitation protocols after repair range from immediate weight-bearing with no range of motion restrictions to non-weight bearing and delayed mobilization for weeks. Pediatric and adolescent patients may require special considerations due to their activity levels, or distinct pathologies such as a discoid meniscus. Further biomechanical and biologic evidence is needed to guide surgical management, postoperative rehabilitation protocols, and future technology applications for traumatic meniscus injuries. [ABSTRACT FROM AUTHOR]

Background: Knee pain is a prevalent issue affecting adolescents and adults, with various causes ranging from acute injuries to chronic conditions like osteoarthritis. The knee is particularly susceptible to injury, especially among athletes. Aquatic therapy has gained attention as a promising approach to knee rehabilitation because of its unique properties, including buoyancy, hydrostatic pressure, and viscosity, which can aid in reducing pain and enhancing recovery. This narrative review explores the effectiveness of aquatic therapy in knee rehabilitation across different knee conditions and presents findings from several studies conducted between 2006 and 2022. Methodology: A comprehensive search strategy was implemented using keywords in Google Scholar and PubMed. The search was limited to randomized controlled trials, systematic reviews, and pilot studies conducted between 2006 and 2022, published in English. Inclusion criteria encompassed original research with outcomes related to knee rehabilitation and aquatic therapy, while articles that did not focus on knee rehabilitation and aquatic therapy or were published prior to 2006 were excluded. Results: Several studies were reviewed to assess the effectiveness of aquatic therapy in knee rehabilitation for different conditions. A total of 7 articles were selected that said the effectiveness of aquatic therapy in knee rehabilitation. Conclusion: In this review, aquatic therapy is effective in all knee conditions. [ABSTRACT FROM AUTHOR]

In this work, an IoT system with edge computing capability is proposed, facilitating the postoperative surveillance of patients who have undergone knee surgery. The main objective is to reliably identify whether a set of orthopedic rehabilitation exercises is executed correctly, which is critical since it is often necessary to supervise patients during the rehabilitation period so as to avoid injuries or long recovery periods. The proposed system leverages the Internet of Things (IoT) paradigm in combination with deep learning and edge computing to classify the extension–flexion movement of one's knee via embedded machine learning (ML) classification algorithms. The contribution of the proposed work is multilayered, as this paper proposes a system tackling the challenges at the embedded system level, algorithmic level, and user-friendliness level considering a performance evaluation, including the metrics at the power consumption level, delay level, and throughput requirement level, as well as its accuracy and reliability. Furthermore, as an outcome of this work, a dataset of labeled knee movements is freely available to the research community with no limitations. It also provides real-time movement detection with an accuracy reaching 100%, which is achieved with an ML model trained to fit a low-cost off-the-shelf Bluetooth Low Energy platform. The proposed edge computing approach allows predictions to be performed on device rather than solely relying on a Cloud service. This yields critical benefits in terms of wireless bandwidth and power conservation, drastically enhancing device autonomy while delivering reduced event detection latency. In particular, the "on device" implementation is able to yield a drastic 99.9% wireless data transfer reduction, a critical 39% prediction delay reduction, and a valuable 17% increase in the event prediction rate considering a reference period of 60 s. Finally, enhanced privacy comprises another significant benefit from the implemented edge computing ML model, as sensitive data can be processed on site and only events or predictions are shared with medical personnel. [ABSTRACT FROM AUTHOR]

Movement is an essential characteristic that has developed over the course of human evolution. With the inclusion of various populations in sports activities, sports have become an important part of people’s daily lives. Knee injuries are common among athletes, with knee joint being the most vulnerable to various injuries. Knee injuries require appropriate treatment to allow the athlete to return to their sports activities. Additionally, this study aimed to increase awareness of the importance of preventing knee injuries in sports and to highlight the potential impact of such injuries on an athlete’s ability to participate in their sport. A cross-sectional study was conducted to evaluate the functional outcomes of athletes with knee injuries. The study included 38 patients with knee injuries (ACL, meniscal injuries, collateral ligament injuries) out of which 21 were physically active athletes, 9 were not, but they were athletes who were not involved in sports at the time of the testing and 8 were recreational athletes. The majority of respondents (76%) reported that they sustained the injury during sports activities. Knee pain was reported as at least once a week by most respondents. The study highlights the importance of proper knee injury prevention measures during sports activities and the need for prompt and effective rehabilitation for those who do suffer injuries. Overall, these findings have important implications for the treatment and management of knee injuries among athletes and individuals seeking to maintain an active lifestyle.

Purpose: To investigate longitudinally the role of mental toughness (MT) in knee rehabilitation in terms of perceived pain and functionality in a sample of older adults with arthritis who adhered to their postsurgery clinic-based rehabilitation protocols and provide suggestions to rehabilitation psychologists. Design: To strengthen the internal validity of this study, we designed our methods and implementation in a way to minimize bias by utilizing the National Institute of Health Quality Assessment Tool for Before–After (Pre–Post) Studies With No Control Group. The data were collected from 92 older-adult patients, who had a diagnosis of osteoarthritis and underwent knee surgery. All patients were diagnosed, underwent surgery, and were evaluated by the same physician. We administered the Oxford Knee Score (OKS) to measure rehabilitation outcomes in terms of pain and functionality and the MT Index (MTI) to measure MT levels three times: 1 day before and 1 and 6 months after the surgery. We used a multilevel growth model to examine the change in the OKS across administrations using MTI scores as a time-varying covariate and sex, age at surgery, and knee as time-invariant covariates. Results: About 62% of the variability in OKS was due to between-patient differences. Of the variability that was attributable to differences within-patient across time, MT accounted for about 38% of the variability. Conclusions: MT could be another, positive psychology-based tool rehabilitation psychologists use to contribute to health promotion efforts to reduce the incidence of disability of older adults with osteoarthritis who undergo knee replacement surgery. Impact and Implications: Following control for in-clinic rehabilitation adherence of patients after total knee replacement surgery, this is the first study to investigate the proportion of variance in knee rehabilitation-related pain and function accounted for by mental toughness (MT) across time and the potential interaction of MT and time on the growth trajectory in knee rehabilitation-related pain and function. The study highlights the importance of considering individual levels of MT in knee rehabilitation outcomes and suggests that nearly 40% of the change across time is accounted for by an individual's MT levels. The findings indicate that healthcare providers, including surgeons and physical therapists, should focus on a multidisciplinary approach to managing the rehabilitation of total knee replacement and consider collaborating with rehabilitation psychologists to develop ways to increase MT levels before surgery. [ABSTRACT FROM AUTHOR]

Based on seminal research from the 1970s and 1980s, the myth that the knees should only move as far anterior during the barbell squat until they vertically align with the tips of the feet in the sagittal plane still exists today. However, the role of both the hip joint and the lumbar spine, which are exposed to high peak torques during this deliberate restriction in range of motion, has remained largely unnoticed in the traditional literature. More recent anthropometric and biomechanical studies have found disparate results regarding anterior knee displacement during barbell squatting. For a large number of athletes, it may be favorable or even necessary to allow a certain degree of anterior knee displacement in order to achieve optimal training outcomes and minimize the biomechanical stress imparted on the lumbar spine and hip. Overall, restricting this natural movement is likely not an effective strategy for healthy trained individuals. With the exception of knee rehabilitation patients, the contemporary literature suggests it should not be practiced on a general basis. [ABSTRACT FROM AUTHOR]

Dynamic loads have short and long-term effects in the rehabilitation of lower limb joints. However, an effective exercise program for lower limb rehabilitation has been debated for a long time. Cycling ergometers were instrumented and used as a tool to mechanically load the lower limbs and track the joint mechano-physiological response in rehabilitation programs. Current cycling ergometers apply symmetrical loading to the limbs, which may not reflect the actual load-bearing capacity of each limb, as in Parkinson's and Multiple Sclerosis diseases. Therefore, the present study aimed to develop a new cycling ergometer capable of applying asymmetric loads to the limbs and validate its function using human tests. The instrumented force sensor and crank position sensing system recorded the kinetics and kinematics of pedaling. This information was used to apply an asymmetric assistive torque only to the target leg using an electric motor. The performance of the proposed cycling ergometer was studied during a cycling task at three different intensities. It was shown that the proposed device reduced the pedaling force of the target leg by 19% to 40%, depending on the exercise intensity. This reduction in pedal force caused a significant reduction in the muscle activity of the target leg (p < 0.001), without affecting the muscle activity of the non-target leg. These results demonstrated that the proposed cycling ergometer device is capable of applying asymmetric loading to lower limbs, and thus has the potential to improve the outcome of exercise interventions in patients with asymmetric function in lower limbs. [ABSTRACT FROM AUTHOR]

Background: The goal of this study was to assess the reliability of electromyography and range of motion measurements obtained using a knee exercise monitoring system. This device was developed to collect data on knee exercise activities. Methods: Twenty healthy individuals performed isotonic quadriceps exercises in this study. The vastus medialis surface electromyography (sEMG) and range of motion (ROM) of the knee were recorded during the exercise using the isotonic knee exercise monitoring device, the Mobi6-6b, and a video camera system. Each subject underwent a second measuring session at least 24 h after the first session. To determine reliability, the intraclass correlation coefficients (ICCs) and standard error of measurement (SEM) at the 95% confidence interval were calculated, and a Bland-Altman analysis was performed. Results: For inter-rater reliability, the ICCs of the mean absolute value (MAV) and root mean square (RMS) of sEMG were 0.73 (0.49, 0.86) and 0.79 (0.61, 0.89), respectively. ROM had an ICC of 0.93 (0.02, 0.98). The intra-rater reliability of the MAV of the sEMG was 0.89 (0.71, 0.96) and the intra-rater reliability of RMS of the sEMG was 0.88 (0.70, 0.95). The ROM between days had an intra-rater reliability of 0.82 (0.54, 0.93). The Bland-Altman analysis demonstrated no systematic bias in the MAV and RMS of sEMG, but revealed a small, systematic bias in ROM (-0.8311 degrees). Conclusion: For sEMG and range of motion measures, the isotonic knee exercise monitoring equipment revealed moderate to excellent inter- and intra-rater agreement. However, the confidence interval of ROM inter-rater reliability was quite large, indicating a small agreement bias; hence, the isotonic knee exercise monitor may not be suitable for measuring ROM. This isotonic knee exercise monitor could detect and collect information on a patient's exercise activity for the benefit of healthcare providers. [ABSTRACT FROM AUTHOR]

This investigation carries out the biomechanical modeling of the knee with the purpose of contributing to rehabilitation therapies for patients who come to the Patronato of Latacunga, through a mathematical model that serves as initial support for the design and the construction of physiotherapy equipment, guaranteeing functionality, safety, and ergonomics to the patients. With the data from the anthropometric study of the population under study, the mathematical variables have been introduced to create a mathematical model with the help of MATLAB/Simulink tool with a focus on the modeling of physical systems, by taking the mechanical system as a biomechanical research because it acts on the bodies in a way that gives them movement, analyzing their laws, variables and elements. A bibliographic method has been used to collect the data, the analytical method to analyze data and variables and the experimental method through the simulation of the model, the developed model is perfectly adaptable to any person, by only changing the variables of the matrix. [ABSTRACT FROM AUTHOR]

We report the case of a 78-year-old woman who presented with a 14-month history of progressive bilateral knee spasms and pain and reduced quality of life. The patient had undergone bilateral total knee arthroplasty after a diagnosis of osteoarthritis and failure of conservative treatment. Symptoms reappeared 8 months postoperatively, and the patient was diagnosed with cervical spondylotic myelopathy. Consequently, she was successfully treated with chiropractic rehabilitation which involved scraping therapy, spinal manipulation, and intermittent motorized traction to relieve cervical nerve pressure. Thus, cervical spondylotic myelopathy should be considered in the differential diagnosis of cases of persistent knee pain. [ABSTRACT FROM AUTHOR]

Knee osteoarthritis (KOA) is a degenerative chronic disease that leads to prolonged pain and permanent damage. Changes in the surrounding muscles of the knee joint may progress together or develop prior to damage in the subchondral bone and articular cartilage. The aim of this review is to review physiotherapeutic interventions that may have a positive effect on muscle function and can improve functional activity in patients with osteoarthritis of the knee. Materials and methods: For the purposes of this publication, an overview of available scientific articles which deal with the application of various physiotherapeutic interventions that may be potentially effective in preventing weakness and affecting muscle function and functional activity in patients with knee osteoarthritis has been reviewed. Results were sought in Pub Med, defining: knee osteoarthritis, functional activity, muscle weakness, prevention, therapeutic exercises, aerobic exercises, resistance ground-based exercises, aquatic exercises, neuromuscular exercises, balance training proprioceptive training, exercises to reduce body weight, tai chi and other traditional exercises. Results: The overview of the available literature found evidence of a positive effect of exercise and therapeutic exercise in patients with knee osteoarthritis, both to prevent the onset and the progression of the disease and to reduce the intensity of the clinical symptoms. Depending on the type of intervention, various mechanisms have been identified that can reduce pain, reduce muscle weakness, improve proprioception, postural balance, and increase functional activity. Conclusion: The use of therapeutic exercises in treatment and rehabilitation of patients with knee osteoarthritis is highly recommended therapy. Therapeutic exercises, depending on their variety, can lead to improved therapeutic outcomes and reduced functional impairment. The application of different type strategies for prevention is an important part of the therapeutic process. When developing strategies for the management of the knee osteoarthritis it is necessary to consider the individual characteristics of the patient and the accompanying comorbidity. There is a need to continue research on the use of therapeutic exercises in order to better understand the mechanism by which they can lead to optimization of functional activity and reduction of adverse effects in patients with knee osteoarthritis. [ABSTRACT FROM AUTHOR]

Three-dimensional human motion analysis provides in-depth understanding in order to optimize sports performance or rehabilitation following disease or injury. Recent developments of statistical methods for functional data allow for novel ways to analyze often complex biomechanical data. Even so, for such methods as well as for traditional well-established statistical methods, the interpretations of the results may be influenced by analysis choices made prior to the analysis. We evaluated the consequences of three such choices when comparing one-leg vertical hop (OLVH) performance in individuals who had ruptured their anterior cruciate ligament (ACL), to that of asymptomatic controls, and also athletes. Kinematic data were analyzed using a statistical approach for functional data, targeting entire curve data. This was done not only for one joint at a time but also for multiple lower limb joints and movement planes simultaneously using a multi-aspect methodology, testing for group differences while also accounting for covariates. We present the results of when an individual representative curve out of three available was either: (1) a mean curve (Mean), (2) a curve from the highest hop (Max), or (3) a curve describing the variability (Var), as a representation of performance stability. We also evaluated choice of sample leg comparison; e.g., ACL-injured leg compared to either the dominant or non-dominant leg of asymptomatic groups. Finally, we explored potential outcome effects of different combinations of included joints. There were slightly more pronounced group differences when using Mean compared to Max, while the specifics of the observed differences depended on the outcome variable. For Var there were less significant group differences. Generally, there were more disparities throughout the hop movement when comparing the injured leg to the dominant leg of controls, resulting in e.g., group differences for trunk and ankle kinematics, for both Mean and Max. When the injured leg was instead compared to the non-dominant leg of controls, there were trunk, hip and knee joint differences. For a more stringent comparison, we suggest considering to compare the injured leg to the non-dominant leg. Finally, the multiple-joint analyses were coherent with the single-joint analyses. The direct effects of analysis choices can be explored interactively by the reader in the Supplementary Material. To summarize, the choices definitively have an impact on the interpretation of a hop test results commonly used in rehabilitation following knee injuries. We therefore strongly recommend well-documented methodological analysis choices with regards to comparisons and representative values of the measures of interests.

Purpose: To present the results of a return to sports bridge program designed to reduce knee injuries following ACL reconstruction and physical therapy. Methods: One hundred and fifty (male = 83, female = 67) patients participated in a whole body neuromuscular control, progressive resistance strength and agility training program. Post-program testing included functional movement form, dynamic knee stability, lower extremity power, agility, and sports skill assessments. Participants completed the Knee Outcome Survey–Sports Activity Scale (KOS-SAS) before and after program initiation. Pre-participation scores were re-estimated following program completion. Results: Global rating KOS-SAS score at program entry was 75 ± 13. Post-program global rating and calculated KOS-SAS were 91.0 ± 9.8 and 90.9 ± 9.7, respectively (p < 0.0001). Pre-participation KOS-SAS score re-estimates at program completion were 54.5 ± 23.3 and 57.3 ± 18.5, respectively. The approximately 20% lower pre-program KOS-SAS score re-estimates (p < 0.0001) observed at program completion suggests that subjects had inaccurately high sports readiness perceptions at program entry. Perceived overall sports activity knee function ratings improved from 2.9 ± 0.6 (abnormal) at program entry to 1.3 ± 0.5 (normal) at completion (p < 0.0001). Most subjects returned back to sports at or above their pre-injury performance skill/performance level (84%, 126/150). By 6.8 ± 3.2 years (range = 2–13 years) post-surgery, ten subjects had sustained an ipsilateral knee re-injury or contralateral knee injury (6.7%). The 2.7% non-contact contralateral and 1.3% non-contact ipsilateral knee injury rates observed were significantly lower than those cited in previous reports. Conclusion: Supplementing primary ACL reconstruction and standard physical therapy with a return to sports bridge program prior to release to unrestricted sports performance was effective at improving patient outcomes and decreasing ipsilateral knee re-injury and contralateral knee injury rates. Level of evidence: II. [ABSTRACT FROM AUTHOR]

This paper presents a knee rehabilitation device to reproduce four exercises generally used in the rehabilitation therapies. The device consists of a mechanical structure based on a 2 DOF parallel mechanism, a controller with PIC-SERVO motion control boards, and a GUI that commands the device to reproduce the rehabilitation exercises. The position kinematic analysis of the mechanism is developed as well as its dimensioning synthesis to cover various leg sizes. This work proposes a technological alternative with significant advantages that responds to the global need for improving physical knee rehabilitation process. A prototype was manufactured and its mobility was validated using a mannequin.

Background: An anti-gravity treadmill has been used in orthopedic and neurological rehabilitation. However, little literature on its use in post-operative knee rehabilitation is available. Objectives: The purpose of this investigation was to study an effect of anti-gravity treadmill on balance in an early phase of postoperative knee rehabilitation. Methods: Forty-nine patients who underwent knee surgery participated in this study (study design: cohort study; level of evidence: level II). At one week post-operatively, each patient was tested for timed single leg stance (SLS) on surgical knee on a floor. Patients were placed onto either AlterG group (AG) or control group (CG) after the test based on their pain level. The patients in AG underwent a balance exercise on AlterG, with the pressure adjusted to a pain-free or minimal pain level, once a day at least 5 days a week. Those in CG underwent their balance exercise on a floor in the same manner. All patients were tested again for SLS at 2 week post-operatively. The lengths of SLS were recorded and analyzed. Results: The lengths of SLS were 38.8 seconds and 19.9 seconds for CG and AG, respectively, at 1 week post-operatively. They improved to 50.5 seconds (CG) and 35.0 seconds (AG) at 2 week post-operatively. There was statistically significant between-group difference at both 1 week and 2 week post-operatively. However, there was no significant between-group difference in improvement from week 1 to week 2. Conclusions: A use of anti-gravity treadmill may have a positive effect on balance in an acute phase of post-operative knee recovery in patients who had an increased level of pain during full weight-bearing immediately after knee operation. [ABSTRACT FROM AUTHOR]

This study suggested a new EMG-signal-based evaluation method for knee rehabilitation that provides not only fragmentary information like muscle power but also in-depth information like muscle fatigue in the field of rehabilitation which it has not been applied to. In our experiment, nine healthy subjects performed straight leg raise exercises which are widely performed for knee rehabilitation. During the exercises, we recorded the joint angle of the leg and EMG signals from four prime movers of the leg: rectus femoris (RFM), vastus lateralis, vastus medialis, and biceps femoris (BFLH). We extracted two parameters to estimate muscle fatigue from the EMG signals, the zero-crossing rate (ZCR) and amplitude of muscle tension (AMT) that can quantitatively assess muscle fatigue from EMG signals. We found a decrease in the ZCR for the RFM and the BFLH in the muscle fatigue condition for most of the subjects. Also, we found increases in the AMT for the RFM and the BFLH. Based on the results, we quantitatively confirmed that in the state of muscle fatigue, the ZCR shows a decreasing trend whereas the AMT shows an increasing trend. Our results show that both the ZCR and AMT are useful parameters for characterizing the EMG signals in the muscle fatigue condition. In addition, our proposed methods are expected to be useful for developing a navigation system for knee rehabilitation exercises by evaluating the two parameters in two-dimensional parameter space. [ABSTRACT FROM AUTHOR]

This paper reports a novel hybridized flexible electromagnetic–triboelectric generator for vibration/deflection monitoring as it is implemented in a cantilever or clamped-clamped configuration. The proposed self-powered sensor operates based on the concepts of electromagnetism and triboelectricity. The fabricated device consists of a stack of magnets and coils, a flexible tube as the main body, and also, highly flexible, mechanically and thermally durable, and cost-effective polymeric materials. The configuration of the electromagnetic component is optimized based on the magnetization direction of the utilized magnets. The device can effectively convert the shear force and bending moment to electrical voltage through the hybridized system with exerting an external force. The performance of the self-powered sensor is investigated for different cases including a single stack and also a double stack of magnetic components. The design of the triboelectric component of the device is based on the vertical contact separation mode. Results of the paper show how the change of configuration of the magnetic components alters the electrical output of the sensor. A detailed experimental analysis is provided to show the capability of the device under different excitation conditions for both triboelectric nanogenerator (TENG) and electromagnetic generator (EMG) components of the sensor. As the experimental analysis shows, the proposed self-powered system has the potential to be utilized for knee rehabilitation, as it shows explicit results under periodical bending load with different frequencies and amplitudes of excitation. [ABSTRACT FROM AUTHOR]

Background: Almost all patients experience neuromuscular disorders of the quadriceps after knee trauma or surgery such as anterior cruciate ligament (ACL) reconstruction. This phenomenon is described in literature as arthrogenic muscle inhibition (AMI). It can be detrimental to patients and cause complications. However, few studies have evaluated the long-term persistence of deficits arising from this, following ACL reconstruction., Purpose: By comparing neuromuscular activation in the lower limb after ACL reconstruction with the unaffected lower limb, after more than 3-years of follow-up, this study aimed to evaluate the possible persistence of long-term deficits after surgery., Methods: Fifty-one patients who underwent ACL reconstruction in 2018 were included in the study, with a minimum follow-up of 3 years. The neuromuscular activation deficit was assessed using the Biarritz Activation Score-Knee (BAS-K), whose intra- and inter-observer reproducibility was also evaluated. The ACL-RSI, KOOS, SANE Leg, Tegner and IKDC scores were also evaluated., Results: The mean BAS-K score of the knee that underwent surgery was 21.8/50 versus 37.9/50 in the healthy knee (p < 0.05). The SANE leg score was 76.8/100 versus 97.6/100 (p < 0.05). The mean IKDC was 84.17 (±12.7). The mean KOOS was 86.2 (±9.2). The mean ACL-RSI was 70 (±7.9) and the Tegner score was 6.3 (±1.2). Intra- and inter-observer reproducibility was satisfactory for the BAS-K score., Conclusion: We found that the neuromuscular activation deficit was high (roughly 42%) at more than 3-years of follow-up after ACL reconstruction. The deficit is not limited to the quadriceps and affects the whole limb. Our findings highlight the need for appropriate rehabilitation after ACL surgery, targeting the corticospinal level in particular., Level of Evidence Iii: prognostic retrospective case-control study., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: As the knee joint is a common site for injury among younger people, the purpose of this study was to measure the skeletal muscle endurance and strength on people with prior anterior cruciate ligament (ACL) knee reconstruction surgery. Method: Young healthy female subjects who reported having knee reconstruction surgery more than one-year prior were tested. The skeletal muscle endurance index (EI) of the hamstrings and quadriceps muscles was determined as the decline in the specific muscle acceleration in response to 2 Hz, 4 Hz, and 6 Hz electrical stimulation. Maximal isometric muscle strength (MVC) was measured in the hamstrings and quadriceps muscles. Results: The hamstrings muscles in the injured leg had less endurance than the non-injured leg at 6 Hz stimulation (55.5 ± 13.2% versus 78.0 ± 13.3%, p < 0.01). Muscle endurance was not reduced in the quadriceps muscles in the injured leg compared to the non-injured leg at 6 Hz stimulation (78.0 ± 13.3% versus 80.3 ± 10.0%, p = 0.45). There were no differences in MVC between the injured and non-injured legs for either the hamstrings (p = 0.20) or quadriceps muscles (p = 0.67). Conclusions: Muscle endurance was reduced in the hamstrings muscles at least one-year post injury, while hamstrings strength was recovered. Reduced hamstrings muscle endurance could be a result of lack of endurance training during rehabilitation. This may contribute to re-injury in the muscle, even in people who have recovered muscle strength.

Purpose: Quadriceps strength deficits persist for years after anterior cruciate ligament (ACL) reconstruction, and patients with these deficits often shift torque demands away from the knee extensors to the hip during functional tasks. However, it is not clear how quadriceps strength deficits may affect hip strength. Therefore, the purpose of this study was to investigate differences in lower extremity strength in individuals with ACL reconstruction with differing levels of quadriceps strength asymmetry. Methods: Isometric strength was recorded bilaterally in 135 participants (73 control and 62 with unilateral ACL reconstruction, time from surgery = 30.9 T 17.6 months) from the knee extensors and flexors, hip extensors and abductors, and hip internal and external rotator muscle groups. Symmetry indices (limb symmetry index (LSI)) were created based on quadriceps strength, and subjects with ACL reconstruction were subdivided (high quadriceps (LSI ≥ 90%), n = 37; low quadriceps (LSI < 85%), n = 18). Individual group (control vs high quadriceps vs low quadriceps) by limb (reconstructed/nondominant vs healthy/dominant) repeated-measures ANOVA was used to compare strength (%BW) for each of the six joint motions of interest (knee extensors/flexors, hip abductors/extensors/external, and internal rotators) while controlling for time from surgery. Results: An interaction was observed for quadriceps strength (P < 0.001), and the reconstructed limb in the low quadriceps group was weaker than all other limbs. A main effect for group was observed with the low quadriceps group having greater hip extension (P = 0.007) strength in both limbs compared with the other groups. Knee flexion strength was weaker in the reconstructed limb of the high quadriceps group (P = 0.047) compared with all other groups and limbs. Conclusions: Individuals with ACL reconstruction and involved limb quadriceps weakness have greater hip extension strength in both limbs compared with patients with bilateral strength symmetry and controls. [ABSTRACT FROM AUTHOR]

A 1-DoF robot is designed and fabricated to be used for knee rehabilitation training. The mechanism (robot) is designed to perform specific set of exercises while the patient is sitting on a chair. The therapy process for patients has different stages; each stage consists of specific exercises to recover the knee to its condition before injury. The maximum torque of healthy joint during the extension/flexion exercise is evaluated by simulation and suitable actuator is selected based on the results. A prototype is then fabricated as a platform to evaluate the design and control concepts. The experiment procedure consisting of three stages of therapy indicates good tracking performance and safe operation of the system.Implication for RehabilitationA 1-DoF mechanism for knee rehabilitation has been designed to perform three stages of therapy: passive, active assist and active resist.The assistive and resistive torque, during active assist and active resist stages, can be set according to the progress in therapy.The results of this study suggest the system has the potential to result in various benefits including reduction of physical workload of physiotherapists and improved repeatability. [ABSTRACT FROM PUBLISHER]

This paper presents the design of an innovative device that applies dynamic mechanical load to human knee joints. Dynamic loading is employed by applying cyclic and periodic force on a target area. The repeated force loading was considered to be an effective modality for repair and rehabilitation of long bones that are subject to ailments like fractures, osteoporosis, osteoarthritis, etc. The proposed device design builds on the knowledge gained in previous animal and mechanical studies. It employs a modified slider-crank linkage mechanism actuated by a brushless Direct Current (DC) motor and provides uniform and cyclic force. The functionality of the device was simulated in a software environment and the structural integrity was analyzed using a finite element method for the prototype construction. The device is controlled by a microcontroller that is programmed to provide the desired loading force at a predetermined frequency and for a specific duration. The device was successfully tested in various experiments for its usability and full functionality. The results reveal that the device works according to the requirements of force magnitude and operational frequency. This device is considered ready to be used for a clinical study to examine whether controlled knee-loading could be an effective regimen for treating the stated bone-related ailments. [ABSTRACT FROM AUTHOR]

Purpose: Despite significant rehabilitation, many athletes experience protracted weakness and faulty mechanics after anterior cruciate ligament reconstruction (ACLR). Clinical tests performed early in rehabilitation, which predict knee mechanics at return-to-sport, are virtually unknown and critically needed to guide clinical decision making. The purpose of this study is to determine if quadriceps strength, Y balance anterior (YB-A) reach distance, and single-leg step-down test performance (SLSD) conducted 3 months post-ACLR are predictive of knee flexion excursion (KFLEX) and knee extensor moment (KEM) during running 6 months post-ACLR. Methods: Thirty (16 females) subjects were collected 3 and 6 months post-ACLR. Age, 21.3 ± 7.6 yr; mass, 69.85 ± 11.4 kg; height, 1.73 ± 0.09 m. At 3 months post-ACLR, subjects performed isometric quadriceps strength testing, YB-A, and SLSD assessments. At 6 months post-ACLR, subjects underwent three-dimensional motion analysis while running on an instrumented treadmill. Pearson correlation coefficients and stepwise multiple regression were used to assess the relationships of 3-month and 6-month variables. Results: Quadriceps strength (r = 0.493, P < 0.01), YB-A (r = 0.394, P = 0.03), and SLSD (r = 0.648, P < 0.01) were significantly correlated to KFLEX. Quadriceps strength (0.505, P < 0.01) and SLSD (.541, P < 0.01) were significantly correlated with KEM, whereas YB-A (.276, P = 0.06) was not. SLSD and quadriceps strength were predictive of KEM (adj R², 0.36; P = 0.001) whereas only SLSD was predictive of KFLEX (adj R², 0.40; P < 0.001). Conclusions: After ACLR, better performance in SLSD and quadriceps strength 3 months postsurgery is predictive of improved sagittal plane knee mechanics during running 6 months postsurgery. [ABSTRACT FROM AUTHOR]