Knee Muscle Strength Research Articles

Rehabilitation exercise program after surgical treatment of patellar tendon rupture: A case report

ObjectiveThis case report describes in detail a rehabilitation and exercise program following surgical treatment of patellar tendon rupture and offers postoperative therapeutic goals and recommendations, with the aim of expediting the resumption of activities of daily living and sports participation following the surgical procedure. In addition, this report analyzes the cause of the patellar tendon rupture in this case. DesignCase report. ParticipantsThe patient, a 25-year-old male recreational athlete (height: 184 cm; weight: 80 kg; right-hand dominant), experienced a complete rupture of the patellar tendon upon landing on the left lower extremity during an unopposed dribble turn. Rehabilitation exercise programA well-structured rehabilitation program was implemented. Passive knee flexion range of motion (ROM) exceeded 90° at week 5 and was fully recovered at week 16. A second surgery was performed at week 19 to remove the decompression wires, and the patient progressively resumed basic physical and specialized training at 7 months post-surgery. Main outcome measuresMorphometric and functional tests were performed to measure the effectiveness of rehabilitation throughout the postoperative process. ConclusionsEarly surgical repair and an immediate postoperative rehabilitation program have a positive impact on knee ROM, function, and muscle strength. The causes of the patellar tendon rupture in this patient included long-standing uncontrolled patellar tendinopathy, impaired mobility of the ankle and hip joints, poor landing technique, and muscle strength imbalances.

Ab. No. 22 Effectiveness of Combined Core Exercises and Routine Rehabilitation in Improving Muscle Strength and Functionality in Knee Osteoarthritis: A 4-Week Intervention Study

Introduction: KOA is progressively disabling in nature, and developing effective treatment strategies is crucial to impede disease progression. Recent research has explored the role of core muscle exercises in mitigating KOA progression. This study evaluates the effectiveness of integrating core strengthening exercises into standard KOA rehabilitation. The study aims to assess the efficacy of incorporating core strengthening exercises and a routine rehabilitation program for knee osteoarthritis (KOA) over 4 weeks and evaluate its impact on physical function tests, knee muscle strength, and core endurance. Methods: Fifteen participants meeting specific KOA criteria completed a four-week intervention combining conventional rehabilitation and core exercises. Selection criteria included orthopedic diagnosis, incorporating medical history, radiographic imaging, and clinical indicators of KOA. A pre-post analysis was done, wherein a portable dynamometer was used to assess for knee muscle strength and physical function tests (stair climb, 30-second sit-to-stand, 40-meter fast-paced walking, and timed up-and-go), and core endurance was evaluated. Statistical analysis using JAMOVI was done, with a significance level of P < 0.05. Result: Knee muscle strength in the affected knee’s flexors and unaffected knee’s extensors and 30-second sit-to-stand showed no significant difference. In contrast, the timed up-and-go test, stair climb test, 40-second fast-paced walking test, and endurance test showed statistically significant differences. Conclusion: After a four-week supervised exercise program, participants exhibited enhanced core endurance and physical function, showcasing the positive effects of exercise in these domains. However, knee muscle strength did not significantly differ, resulting in the need for longer follow-up studies. The study implies that integrating core exercises into routine KOA rehabilitation can enhance physical function and endurance, emphasizing the need for their inclusion in long-term treatment plans for KOA patients.

Impact of lower limb alignment abnormality (physiologic knee valgus) on the functional recovery outcome of athletes with meniscal injuries.

This study aimed to investigate the impact of lower limb alignment abnormalities, specifically physiological knee valgus, on the functional recovery outcomes of athletes with meniscal injuries. It also examined the factors influencing these abnormalities to provide scientific evidence for treatment and rehabilitation of related sports injuries. We conducted a retrospective study of 118 athletes from Guizhou Normal University, who were divided into two groups based on the presence or absence of lower limb alignment abnormalities. The Simple group comprised athletes with isolated meniscal injuries, while the Combined group included athletes with meniscal injuries and concurrent lower limb alignment abnormalities. We assessed the functional status of both groups and analyzed factors influencing lower limb alignment abnormalities. Of the 118 athletes, 46 (38.98%) exhibited lower limb alignment abnormalities, and 72 (61.02%) did not. No significant differences in general characteristics were found between the groups (all P > 0.05). The Combined group displayed higher Visual Analog Scale (VAS) scores and Functional Performance Test (FPT) results (coordinated contraction, shuttle run, CarioCa) compared to the Simple group (P < 0.05). Conversely, joint range of motion (ROM), knee muscle strength (flexors), and International Knee Documentation Committee (IKDC) scores were lower in the Combined group (all P < 0.05). Multivariate logistic regression analysis identified active ROM < 105.32°, passive ROM < 101.66°, and knee muscle strength (flexors) < 84.41 N as risk factors for lower limb alignment abnormalities (P < 0.05), while FPT acted as a protective factor (P < 0.05). The combined testing model demonstrated higher predictive efficacy (AUC = 0.903, 95% CI: 0.852-0.955, P < 0.001). Lower limb alignment abnormalities significantly affect the functional recovery outcomes of athletes with meniscal injuries. Factors such as ROM, knee muscle strength, and IKDC score may pose risks for these abnormalities, whereas FPT can provide protective benefits. Timely detection and correction of lower limb alignment abnormalities during the rehabilitation process from meniscal injuries are crucial to enhance recovery and improve prognosis.

Importance of muscle strength to maintain mobility, but not to maintain postural balance in older women: Cross-sectional study

BackgroundAcknowledging the relationship between postural control and muscle strength in lower limbs is important to find persons with high fall risk and to design fall prevention exercise programs. ObjectiveTo investigate the connection between knee muscle strength, semi-static postural balance, and functional mobility in irregularly active older women. MethodsOne hundred and ten older women aged 60 to 85 years underwent a semi-static postural balance test in a force and functional mobility measured by Timed Up & Go (TUG) with and without Cognitive Tasks (CT). Muscle strength of the knee was assessed by isokinetic dynamometry at 60°/s. ResultsA negative correlation between the functional mobility (TUG with and without CT) and the muscular strength of the knee was observed. Regarding semi-static balance, there was a low negative correlation with peak torque corrected for body weight of the extensors with the following variables with eyes open: Mean Velocity Dominant limb (D) (r = -0.19; p = 0.03); and anteroposterior range Non-Dominant limb (ND) (r = -0.19; p = 0.04); with eyes closed: mediolateral range ND limb (r = -0.21; p = 0.02) and Mean Velocity ND limb (r = -0.18; p = 0.05). ConclusionsThis study found that better functional mobility was associated with greater muscle strength in the knee in elderly women. There were weak negative correlations between knee extensor strength and some measures of semi-static postural balance, suggesting that different motor control actions are required to maintain semi-static balance and mobility. In the case of semi-static balance, a lower level of muscle response is required than in functional mobility.

Association between muscle strength and depression in a cohort of young adults.

The study investigated the association between knee joint muscle strength and the prevalence of depression in a cohort of young adults. The observational, population-based study was performed with 909 participants (29.02 ± 2.03 years; 48.73% male) from the Central European Longitudinal Studies of Parents and Children: Young Adults (CELSPAC: YA), who were retained to analysis. Quadriceps and hamstring knee muscle strength were assessed by isokinetic dynamometry, and depression by Beck's Depression Inventory (BDI-II). Statistical comparisons (Mann-Whitney and Chi-squared test) and effect size analyses (Eta-Squared, and Odds Ratio) were conducted. The main findings revealed an inverse association between knee joint muscle strength and depression, with individuals who had low muscle strength having 3.15 (95% CI = 2.74-3.62) times higher odds of experiencing depression. Specifically, participants with low extensor strength had 4.63 (95% CI = 2.20-9.74) times higher odds, and those with low flexor strength had 2.68 (95% CI = 1.47-4.89) times higher odds of experiencing depression compared to those individuals with high muscle strength. Furthermore, gender-specific analyses revealed that males with low muscle strength had 2.51 (95% CI = 1.53-4.14) times higher odds, while females had 3.46 (95% CI = 2.93-4.08) times higher odds of experiencing depression compared to individuals with high muscle strength. Strong knee muscles seems to be a key factor in preventing depression, specially in female young adults. The results support the importance of promoting an increase in muscle strength through physical activity as a preventive strategy against depression in this population.

Effect of Nordic Hamstring Exercises on the Balance of Knee Muscle Strength in Sprinters

Objective: The purpose of this study was to investigate the effect of Nordic hamstring exercises on the balance of knee muscle strength in sprinters. Methods: In this paper, a total of 20 well-trained sprinters were selected as subjects to participate in this experiment, 10 of them were subjected to Nordic hamstring exercise intervention, and the other 10 were treated as control group without any intervention. At different time points before and after intervention, the isokinetic muscle strength and test system were used to analyze the changes of muscle strength of athletes after Nordic hamstring exercise intervention. Results: The H:Q functional ratio changed over time after the intervention: decreased by 0.072 from baseline 24 hours after the intervention, recovered by 0.039 from 24 hours at 48 hours, and recovered by 0.024 from 72 hours at 48 hours. In general, there was a significant decline at 24 hours, and then a gradual recovery at 48 and 72 hours, but a partial recovery was observed overall. Conclusions: After the Nordic hamstring exercise intervention, the H:Q functional ratio showed a significant decline at 24 hours, and then gradually recovered at 48 and 72 hours, but overall partial recovery was observed. It is suggested that the injury risk of sprinters will increase in the short term after intervention, and the injury risk can be avoided by at least 48 hours of recovery.

Effect of eccentric isokinetic exercise on muscle strength and functional recovery after anterior cruciate ligament reconstruction

BackgroundPrevious studies have shown isokinetic exercise forms an important part in reconditioning the patients after anterior cruciate ligament reconstruction (ACLR) in regaining muscle strength and knee function. Although eccentric isokinetic training has been shown to enhance quadriceps muscle strength, the application toward benefiting patients after ACLR remains controversial. The present study aims to investigate the benefits of eccentric over concentric isokinetic exercises on knee muscle strength and its value in later stage of rehabilitation, including the return-to-sport. MethodsThirty-six patients who had undergone ACLR for 4-to-6 months were assigned to receive either eccentric or concentric isokinetic training weekly for six weeks on top of their standardized post-operative exercise programme. The assessments include isokinetic test on the peak torques of quadriceps and hamstrings, single-leg hop test and ability to return-to-sport. ResultsBoth groups demonstrated significant gains on peak torques in quadriceps and hamstrings after training. At post-intervention, the peak torques for both quadriceps (p = 0.005) and hamstrings (p = 0.017) of the ACL-reconstructed limb from eccentric training were significantly higher than concentric training. The significant improvement was similarly demonstrated in the limb symmetry index (LSI) in hamstrings (p = 0.016) of the ACL-reconstructed limb from eccentric training. Moreover, eccentric group performed significantly better in single-leg hop tests (p = 0.042). Most importantly, eccentric group have higher percentages of return-to-sport (55.6 %) than concentric group (27.8 %). ConclusionA 6-week course of eccentric isokinetic training was more effective than concentric isokinetic training in increasing quadriceps and hamstrings strength in terms of peak torques. Importantly, the better functional performance after the eccentric isokinetic exercise account for higher return-to-sport ratio.

Effect of adding hip exercises to general rehabilitation treatment of knee osteoarthritis on patients’ physical functions: a randomized clinical trial

BackgroundHip adductor and abductor strength were both reduced in KOA patients. But to date, most of the researches have only focused on quadriceps combined with hip abductor strengthening versus quadriceps strengthening.ObjectiveThe aim of the study is to evaluate the effect of adding hip abductor and adductor strengthening to quadriceps strengthening on lower limb strength, knee pain and physical function in patients with medial compartmental knee osteoarthritis.MethodsIn this study, 42 participants, were randomly divided into two groups: the general treatment group (GT group) and the added-hip-exercise group (AH group). All participants were given a general rehabilitation treatment. The AH group performed hip abductor and adductor strengthening in addition to the general rehabilitation treatment. Knee and hip muscle strength, Five Times Sit-to-Stand Test (FTSST), the Timed Up and Go Test (TUGT), Numerical Rating Scale (NRS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were assessed at baseline and 6 weeks. A two-sided 2-sample unpaired t test was performed to compare the difference in mean change scores between AH and GT groups.ResultsFinally, 36 participants completed the study: both groups consist of 18 participants. In the per-protocol analysis, the AH group had a greater improvement in knee extension strength (mean changes, 7.84 versus 36.48; P < 0.001) and hip abduction strength (mean changes, 5.05 versus 26.62; P = 0.001) than the control group. Similarly, the AH group had a greater improvement in the FTSST time (mean changes, 0.40 s versus 3.57 s; P < 0.001) and the TUFT time (mean changes, 0.18 s versus 1.67 s; P = 0.002) than the GH group. No statistical difference was found in the change of WOMAC pain scores and NRS between the 2 groups.ConclusionsOlder adults with knee OA in the AH group had superior muscle strength, symptoms and daily activity performance at the 6th week than those in the GT group. And adding hip exercises could expedite improvement of pain at the 2th week, but not at the 6th week.Trial registrationClinical trial registration numbers and date of registration: ChiCTR-IOR-16009124, Registered 30 August 2016.

Home-based exercise program and Health education in patients with patellofemoral pain: a randomized controlled trial

BackgroundPatellofemoral pain (PFP) is one of the most common disorders of the knee joint. Home-based exercise is an effective intervention to achieve self-management for chronic diseases. This study evaluated the effects of home-based exercise and health education in patients with PFP.MethodsPatients who had PFP were randomly allocated to an intervention group (IG) or control group (CG). Patients in the IG received a 6-week tailored home-based exercise program with health education via remote support, while patients in the CG group only received health education. Clinical outcomes were compared using the Anterior Knee Pain Scale (AKPS) to measure function and the Visual Analog Scale (VAS) to measure “worst pain” and “pain with daily activity”. Muscle strength was measured according to the peak torque of the knee muscles using an isokinetic system.ResultsAmong a total of 112 participants screened for eligibility, 38 were randomized and analyzed, including 19 participants in the intervention group and 19 participants in the control group. There were no significant differences in baseline characteristics between the groups. At 6-week follow-up, the intervention group showed a greater worst pain reduction (between-group difference, -19.3 [95%CI, -23.2 to -15.5]; P < 0.01) and pain with daily activity (between-group difference, -22.9 [95%CI, -28.3 to -17.4]; P < 0.01) than the control group. Similarly, the intervention group had better improvements in AKPS (between-group difference, 9.0 [95%CI, 4.1 to 13.9]; P < 0.01) and knee extensor strength (between-group difference, 20.1 [95%CI, 14.5 to 25.8]; P < 0.01), compared to the control group. No adverse events were reported.ConclusionHome-based exercise and health education resulted in less pain, better function, and higher knee muscle strength compared with no exercise in patients with PFP. A large randomized controlled trial with long-term follow-up is required to confirm these findings.Trial registrationChinese Clinical Trial Registry, ChiCTR2200056224 (https://www.chictr.org.cn/showproj.aspx?proj=135506). Registered on February 1, 2022.

The effects of strength and balance exercises on the center of pressure and plantar pressure distribution in adolescent ballet dancers

ABSTRACT We aimed to examine whether the changes in neuromuscular strength indices and balance affect the gait patterns of five fundamental ballet techniques performed on a single leg after 8-weeks of strength+balance exercise coupled with traditional ballet classes. Thirty female ballet dancers were recruited (age:12.77 ± 1.52y). Anthropometric parameters, isokinetic ankle, knee, hip, and trunk muscle strength, and static and dynamic gait kinematics were performed using a repeated measures study design. The exercise group revealed greater knee, hip, ankle, and trunk muscle strength and lower center of pressure (COP) during follow-up measurements (p < 0.05, p < 0.001). Hip and trunk muscle strength was inversely correlated with heel impulse parameters (p < 0.05). Reduced R2 values were revealed for the normalized impulse measures of the forefoot, during all five techniques. However, an increase in normalized impulse measures of the heel region of the foot, on average, to a decrease in percent forefoot/rearfoot impulse and explained a significant proportion of variance in passé (R2 = 0.87), développé à la seconde side (R2 = 0.73), développé à la seconde front (R2 = 0.74), développé à la seconde back (R2 = 0.90), and penché (R2 = 0.84) heel impulse parameters. Muscle strengthening exercises and impulse-based load patterns of foot regions and COP may be used to verify the effectiveness of such treatments in redistributing the pressure throughout the foot.

Changes in the Force-Velocity Relationship of Knee Muscles After Anterior Cruciate Ligament Reconstruction Using the Isokinetic 2-Point Model.

After anterior cruciate ligament reconstruction (ACL-R), knee muscle strength symmetry is used as part of the return-to-sport criteria. However, little is known about the changes in the force-velocity (F-V) relationship, which could affect athletic performance. This study investigated the F-V relationship of knee muscles at 4 and 8months after ACL-R, using the 2-point method tested by isokinetic dynamometry. A total of 103 physically trained individuals (24.6 [9.3]y, 59.2% male) who underwent primary ACL-R were included. Demographic information and surgery characteristics were collected at 6weeks postoperatively. Isokinetic knee flexors' and extensors' peak torques were measured at 60° and 240° per second in the concentric mode at 4 and 8 monthspostoperative. Peak torques and angular velocities were converted to force and linear velocity for calculating maximum isometric force (F0) and the slope of the regression line (F-V slope). At 4 and 8 months postoperative, F0 was significantly lower and F-V slope was significantly less steep (less negative) on the operated leg compared with the nonoperated leg for knee extensors (P < .001) and flexors (P < .001-.002). The limb symmetry index calculated using F0 was lower than the limb symmetry indexes assessed at 60° and 240° per second, especially for knee flexors (P < .001). The use of patellar tendon grafts was associated with lower F0 and a less steep F-V slope compared with hamstring tendon grafts (P < .010). The isokinetic 2-point model assessing the F-V relationship provides additional and relevant insight for evaluating knee muscle strength after ACL-R.

Effectiveness of exercise for improving physical and renal function in older adults with pre-dialysis chronic kidney disease: A systematic review and meta-analysis

Purpose : Exercise may prevent the worsening of chronic kidney disease (CKD) and progression of cardiovascular diseases in patients with CKD. This review aims to identify the best type of exercise modality and summarizes the beneficial effects of exercise on physical and renal function among older adults with pre-dialysis CKD.Methods : A systematic search of PubMed, Embase, CINAHL, Cochrane Library, Web of Science, SCOPUS, and domestic database was performed for randomized controlled trials (RCTs) assessing the effect of exercise intervention on older adults with pre-dialysis CKD published until February 2023. A random-effects metaanalysis was conducted. The risk of bias was assessed using a Cochrane tool for assessing the risk of bias in RCTs (RoB 2.0).Results : The systematic review included 11 RCTs (n = 591, average age 60.2–76), of which 8 could be included for meta-analysis. Exercise was significant in increasing peak oxygen consumption and knee muscle strength among physical functions, and also in improving glomerular filtration rate among kidney functions.Conclusion : Exercise has beneficial effects on physical and renal function among older adults with pre-dialysis CKD. In the future, it is necessary to verify the effectiveness of exercise by subdividing it by type, intensity, duration, and delivery.

The association between knee muscle performance and clinical outcomes of knee function 1–4 years after a sport-related knee joint injury

ObjectiveEstimate the association between index leg knee muscle strength and rate of torque development (RTD), and self-reported and performance-based (i.e., hop) knee function in persons 1–4 years after a sport-related knee joint injury. MethodsData were collected at baseline of a clinical trial. Assessments included the Knee injury and Osteoarthritis Outcome Score Sport & Recreation subscale (KOOSsport), 6-m timed hop (TH), and peak concentric isokinetic knee extensor and flexor torque and isometric RTD. Associations between peak torque and RTD with KOOSsport and TH were assessed using multivariable regression with nonlinear transformations. Results53 participants (64.2% female) were included. Knee extensor peak torque was nonlinearly related to TH time, with a strong inverse relationship at lower torque values that changed as torque increased. Results were inconsistent for flexor peak torque, extensor RTD and flexor RTD, with inconsistencies in relationship shape and estimates of association between primary and sensitivity analyses. There was no association between strength/RTD and KOOSsport. ConclusionThere was a nonlinear relationship between knee extensor strength and hop function, with lower strength being associated with a stronger relationship. As strength values increased, the relationship attenuated. Knee extensor and flexor strength, or RTD, were not associated with self-reported function.

The Addition of the Gracilis Tendon to a Semitendinosus Tendon Autograft Is Not Associated With Knee Muscle Strength, Subjective Knee Function, or Revision Surgery After Anterior Cruciate Ligament Reconstruction

PurposeTo evaluate and compare isokinetic knee muscle (extension and flexion) strength, single-leg-hop (SLH) test performance, anterior knee laxity, subjective knee function and the 2-year revision surgery risk between patients who underwent anterior cruciate ligament (ACL) reconstruction (ACLR) with a semitendinosus tendon autograft (ST) or a semitendinosus and gracilis tendon autograft (ST+G). MethodsPatients aged 16 years or older who underwent primary ACLR with a hamstring tendon autograft at our institution from January 2005 to December 2020, with no associated ligament injuries, were identified. Isokinetic knee muscle strength and SLH test performance were assessed 6 months postoperatively. Anterior knee laxity (KT-1000 arthrometer, 134-N) was assessed preoperatively and 6 months postoperatively. The Knee injury and Osteoarthritis Outcome Score (KOOS) was collected preoperatively and 1 and 2 years postoperatively. Patients who underwent revision ACLR at any institution in the country within 2 years of primary surgery were identified through the Swedish National Knee Ligament Registry. ResultsA total of 6,974 patients (5,479 ST and 1,495 ST+G) were included. There were no significant differences in extension and flexion strength or SLH test performance between the groups. Preoperatively, there was no significant difference in knee laxity between the ST and ST+G groups. Postoperatively, the ST+G group had a significantly increased mean side-to-side (STS) laxity (2.1 ± 2.3 mm vs 1.7 ± 2.2 mm; P <.001) and showed a trend towards an increased STS laxity according to the IKDC form, with significantly fewer patients with an STS laxity of ≤ 2 mm (58.4% vs 65.8%) and significantly more patients with an STS laxity of between 3 and 5 mm (35.0% vs 29.9%) or > 5 mm (6.6% vs 4.3%) (P < .001). The only significant difference in subjective knee function was for the KOOS Quality of Life score in favor of the ST group preoperatively (37.3 ± 21.4 vs 35.1 ± 19.9; P = .001). No other significant differences between the groups were found preoperatively and 1 and 2 years postoperatively for any of the KOOS subscales. The overall revision ACLR rate within 2 years of primary surgery was 2.0% (138/6,974). The revision ACLR risk for the ST+G group (1.7%; 25/1,495) was not significantly different from that of the ST group (2.1%; 113/5,479) (Hazard Ratio [HR] 0.80; 95%, CI, 0.50-1.24; P = .32). ConclusionThe addition of the gracilis tendon to an ST autograft was not associated with knee muscle strength, SLH test performance, subjective knee function or the risk of revision surgery after ACLR. Level of EvidenceLevel III, retrospective comparative study

Exploring Isokinetic Test, Joint Position of Sense and Dynamic Balance in Anterior Cruciate Ligament Reconstruction versus Healthy Subjects

Reduced knee muscle strength, joint position sense (JPS), and dynamic balance are some of the impacts of anterior cruciate ligament (ACL) rupture that remained in patients after surgery. The goal of this study was to assess patients who had finished a sport rehabilitation programme and were back exercising with their healthy partners for the JPS, dynamic balance, and knee muscle strength. In this study, 40 male soccer players—20 participants with autograft reconstruction of the hamstring or surgery, and 20 uninjured participants—took part. By using isokinetic dynamometry, the flexor and extensor peak torque of the knee at angular velocities of 60 deg. s-1, JPS at 60°, and dynamic stability were assessed in the dominant leg by using Y balance test. The independent t-test was utilized to compare the outcomes between the two groups. The findings demonstrated that there were no differences in any of the test parameters for determining muscle strength and JPS between the two groups at 60 degrees per second in the dominant leg. (p &amp;gt; 0.05). Furthermore, there was no observed difference in all directions of YBT between Injured and healthy groups in dominant leg (p &amp;gt; 0.05). The results of this study allow us to make the conclusion that when a rehabilitation programme has been completed successfully, surgically induced outcomes may be improved and the risk of re-injury in athletes may be decreased.

Effect of isokinetic muscle strength training on knee muscle strength, proprioception, and balance ability in athletes with anterior cruciate ligament reconstruction: a randomised control trial.

Objective: This study aimed to investigate the effects of regular isokinetic muscle strength training on knee muscle strength, proprioception, and balance ability in athletes after anterior cruciate ligament (ACL) reconstruction. Methods: Forty-one athletes who underwent ACL reconstruction were randomly divided into the experimental (n = 21) and control (n = 20) groups. The experimental group used an isokinetic muscle strength tester for 4weeks (five times/ week) of knee flexion and extension isokinetic muscle strength training. The control group used the knee joint trainer (pneumatic resistance) for the same exercise regimen as the experimental group. Results: 1) Four weeks when compared with the baseline. Experimental group: the knee flexion and extension PT (60°/s and 240°/s) increased by 31.7%, 40.3%, 23.4%, and 42.9% (p < 0.01), and the flexion muscular endurance increased by 21.4% and 19.7% (p < 0.01). The flexion and extension kinaesthesia and the 30° and 60° position sense decreased by 36.2%, 32.3%, 40.0%, and 18.9% (p < 0.05). The anterior-posterior and medial-lateral displacement and speed decreased by 30.2%, 44.2%, 38.4%, and 24.0% (p < 0.05). Control group: the knee peak torque (60°/s) increased by 18.8% (p < 0.01). The anterior-posterior and medial-lateral displacement and speed decreased by 14.9%, 40.0%, 26.8%, and 19.5% (p < 0.01). 2) After 4weeks, compared with the control group, the knee flexion and extension peak torque (60°/s), extension, peak torque (240°/s), and extension muscular endurance of the treatment group increased to varying degrees (p < 0.05). However, the kinaesthesia, 30° position sense, and anterior-posterior displacement decreased to varying degrees (p < 0.05). Conclusion: Adding regular isokinetic muscle strength training to rehabilitation training further improved the knee flexion and extensor strength and extensor endurance of athletes with ACL reconstruction, as well as enhanced the kinaesthesia and 30° position sense and the balance between the anterior and posterior directions. However, the treatment had limited effects on knee flexion kinaesthesia and muscle endurance.

Effectiveness of a theory-driven mHealth intervention in promoting post-surgery rehabilitation adherence in patients who had anterior cruciate ligament reconstruction: A randomized clinical trial

RationalePatients with anterior cruciate ligament (ACL) reconstruction often have poor adherence to post-surgery rehabilitation. ObjectiveThis study applied the integrated model of self-determination theory and the theory of planned behavior to examine the effects of a smartphone-delivered intervention on the recovery outcomes of patients with an ACL rupture during post-surgery rehabilitation period. Additionally, we explored the effects of the intervention on participants with different beliefs toward rehabilitation at baseline. MethodsThe randomized control trial recruited 96 eligible participants (M age = 27.82 years, SD = 8.73; female = 39%) who underwent ACL reconstruction surgery. Participants were randomly assigned to an intervention group (n = 41), which received standard post-surgical treatment (usual-care) and smartphone application (“ACL-Well”), or a usual-care control group (n = 55). The primary outcomes were recovery outcomes from ACL surgery measured by knee muscle strength and laxity, and subjective knee evaluation completed 4-month post-intervention. Secondary outcomes were the psychological and behavioral outcomes measured at baseline, at 2- and 4-month post-intervention. ResultsANCOVA indicated no significant between-group differences in primary outcomes: knee muscle strength, knee laxity and subjective knee evaluation, Fs(1, 27 to 55) = 0.01 to 1.36, p = .25 to .99, η2 = 0.01 to 0.03. For the secondary outcomes, growth mixture modelling revealed self-determined treatment motivation declined significantly over the intervention period in the control group (M slope = −0.39 to −0.12, p = .01 to .04), but not in the intervention group (M slope = −0.19 to −0.08, p = .06 to .38). ConclusionsThe smartphone application fell short in promoting orthopedic outpatients' recovery outcomes. Yet, it shows some promises as a mean to maintain patients’ motivation and adherence to treatment.

Factors Associated With Sports Function and Psychological Readiness to Return to Sports at 12 Months After Anterior Cruciate Ligament Reconstruction: A Cross-sectional Study

Background: Sports function and psychological readiness to return to sports (RTS) are important outcomes when evaluating rehabilitation after anterior cruciate ligament reconstruction (ACLR). It is, however, unclear which specific factors contribute most to these outcomes. Purpose: To determine associations between demographic characteristics, objective measurements of physical function, patient-reported outcome measure scores, sports-related function assessed with the Knee injury and Osteoarthritis Outcome Score (KOOS) Sport and Recreation subscale, and psychological readiness to RTS assessed with the Anterior Cruciate Ligament–Return to Sport after Injury (ACL-RSI) scale at 1 year after ACLR. Study Design: Cross-sectional study; Level of evidence, 3. Methods: At a mean of 12.5 ± 2.0 months after ACLR, 143 participants (50.3% female), with a mean age of 25.0 ± 5.7 years, were assessed for demographic characteristics, physical factors (hop performance, muscle strength, ankle and hip range of motion), and psychological factors (KOOS Pain and Symptoms subscales, Perceived Stress Scale, fear of reinjury) as well as the KOOS Sport and Recreation subscale and ACL-RSI scale. Backward linear regression models were used to evaluate factors associated with sports function and psychological readiness to RTS. Results: Lower isokinetic knee extension peak torque (limb symmetry index) (B = 18.38 [95% CI, 3.01-33.75]), lower preinjury activity level (B = 2.00 [95% CI, 0.87-3.14]), greater knee pain (B = 0.90 [95% CI, 0.70-1.10]), shorter time between injury and reconstruction (B = 0.16 [95% CI, 0.05-0.26]), and greater fear of reinjury (B = 0.11 [95% CI, 0.01-0.20]) were associated with a worse KOOS Sport and Recreation subscore (R2 = 0.683). A shorter hop distance (B = 0.15 [95% CI, 0.00-0.29]) was associated with a lower ACL-RSI score (R2 = 0.245). Conclusion: A combination of knee muscle strength, activity level, knee pain, timing of surgery, and fear of reinjury accounted for approximately 70% of the variation in sports function at 1 year after ACLR. In contrast, there was only 1 weak association between physical function and psychological readiness to RTS at this time point. Thus, factors associated with current sports function are much better known than features related to psychological readiness to RTS.

Longitudinal Development of Physical Characteristics and Function in Japanese Junior Rugby Union Players.

To longitudinally investigate the development of physical characteristics and function during 3years of high school among Japanese junior rugby players and examine the differences in these parameters between the positions. In 83 junior rugby players (forwards: n = 46, backs: n = 37) from one Japanese high school team who had participated in national high school competitions, anthropometric variables (height, body mass, fat and lean body mass, and body mass index), upper- and lower-body strength (eg,1-repetition-maximum [1RM] bench press, isokinetic knee muscle strength at 60°/s and 180°/s), and sprint and jump performance were measured. Upper- and lower-body strength relative to body mass and lean body mass were also calculated. All anthropometric indices improved with increasing age, and the values were higher in forwards than in backs (all P < .05). The 1-repetition maximum bench press (forwards: 40.8%, backs: 52.5%) and isokinetic knee strength (eg,extension at 60°/s, forwards: 15.4%, backs: 10.0%) improved with age (from 16 to 18y), and they were higher in forwards than in backs (all P < .05). Meanwhile, the 1RM bench press relative to lean body mass did not differ between the positions. Isokinetic knee muscle strength at 60°/s and 180°/s relative to lean body mass and sprint and jump performance did not improve with age. These results indicate that Japanese junior rugby players need to develop larger physiques and continuously increase their lower-body strength to improve sprint and jump performance.

A comparison between hypertonic dextrose prolotherapy and conventional physiotherapy in patients with knee osteoarthritis.

The aim of the present study was to compare the efficacy of hypertonic dextrose prolotherapy (HDP) with conventional physiotherapy (CPT) in improving symptoms in females with knee osteoarthritis (OA). The present study included 60 patients with a diagnosis of knee OA. The patients were randomly assigned to the HDP (n=30) and CPT (n=30) groups. The patients in the HDP group were treated with a dextrose injection into the knee joint (25% dextrose) and around the knee (15% dextrose) in two sessions for 1 month, while those in the CPT group received a hot pack, transcutaneous electrical nerve stimulation and therapeutic ultrasound in five sessions a week for 4 weeks. Prior to commencing the treatment, and at 1 and 3 months post-treatment, all the patients were evaluated using the visual analog scale (VAS), Western Ontario and McMaster Osteoarthritis Index (WOMAC), the goniometric measurement of active knee range of motion (ROM), a 50-m walking test and isokinetic knee muscle strength measurements. There were no statistically significant differences between the two groups as regards the demographic characteristics at pre-treatment (P>0.05). However, at 1 and 3 months post-treatment, the scores of all the outcome parameters were significantly improved in the HDP group compared with the CPT group (P<0.05 for all). In both groups, a significant improvement was observed in the VAS scores, WOMAC total values and ROM following the treatments, with the greatest improvement observed in the HDP group (P<0.001). The isokinetic quadriceps peak torque measurements were increased in both groups following treatment. All the scores exhibited a statistically significant improvement in the HDP group at both 1 and 3 months post-treatment. On the whole, the results of the present study demonstrate that both HDP and CPT are effective treatment modalities to relieve pain, and increase functionality and strength in patients with knee OA. However, greater improvements in pain and functionality can be achieved with prolotherapy.