Search Results (27)

Objectives: This study aimed to evaluate longitudinal changes in knee muscle strength following open wedge high tibial osteotomy (OWHTO) for medial compartment knee osteoarthritis with varus deformity, with particular emphasis on differences between the operated and non-operated knees. Methods: This retrospective study included 78 patients who underwent OWHTO. All patients followed a standardized rehabilitation protocol consisting of protected weight-bearing for six weeks, followed by closed kinetic chain exercises and subsequent open kinetic chain exercises from three months postoperatively. Isokinetic knee extension and flexion strength were assessed preoperatively and at 3, 6, and 12 months postoperatively using a Biodex System IV dynamometer at angular velocities of 60°/s and 180°/s. Absolute muscle strength values and inter-limb strength deficits were analyzed. Statistical analyses were performed using the Shapiro–Wilk, Friedman, and Wilcoxon signed-rank tests, with significance set at p ≤ 0.05. Results: At 60°/s, knee extensor and flexor strength deficits significantly increased after surgery, peaking at three months postoperatively, and gradually improved; however, deficits remained significantly greater than preoperative values at one year (p < 0.05). Similar trends were observed at 180°/s, although they did not reach statistical significance. These deficits were primarily attributable to reduced muscle strength in the operated knee, while strength in the non-operated knee remained unchanged throughout follow-up. Conclusions: Knee muscle strength in the operated limb markedly declined during the first three months following OWHTO, particularly in maximal power, and generally required more than six months to recover toward preoperative levels. These findings emphasize the importance of targeted postoperative rehabilitation strategies focusing on early muscle power recovery after OWHTO. Full article

Background/Objective: Kinesiology tape (KT) is commonly used in sports medicine and rehabilitation, but its impact on muscle strength over time remains unclear. Female futsal athletes experience high quadriceps demands and are at risk of anterior cruciate ligament injury; however, this population remains understudied. The purpose of this study was to investigate the longitudinal effect of repeated kinesiology taping applications on quadriceps muscle strength and lower limb function in female futsal players. Method: A longitudinal pilot randomized controlled trial was conducted during the Saudi Universities Sports Federation Futsal Championship. Twelve female athletes (aged 19–25 years) were randomly allocated to a KT (n = 6) or control group (n = 6). The KT protocol followed the standardized quadriceps facilitation guidelines and was applied repeatedly over 30 days. We measured isometric strength (hand-held dynamometer), eccentric/concentric torque and power (Biodex System), and functional performance (single-leg hop). Nonparametric tests (Wilcoxon signed-rank and Mann–Whitney U) and mixed ANOVA were used for analysis. Result: Post-intervention, the KT group demonstrated significant improvements in isometric strength (p = 0.03, r = 0.90), eccentric/concentric strength (p = 0.03, r = 0.90), and lower limb function (p = 0.03, r = 0.90). The between-group comparisons showed significant advantages for the KT group in isometric (p = 0.01, r = 0.83) and eccentric/concentric strength (p < 0.05, r = 0.67–0.74), but not in lower limb function (p = 0.20, r = 0.37). Conclusions: Repeated kinesiology taping over a 30-day period led to statistically greater longitudinal improvements in quadriceps muscle strength but did not affect functional performance. Kinesiology taping represents a non-invasive, low-cost treatment option for quadriceps strength measures in sports characterized by higher demands on the quadriceps, especially for female athletes with contributing injury risks. Further trials with more participants and a longer follow-up should be conducted. Full article

Objectives: This study aimed to evaluate the effect of a superior ankle traction manipulation on the strength and electrical activity (surface EMG) of the peroneus longus, gluteus medius, and tensor fasciae latae muscles in healthy young adults. Methods: In total, 30 healthy participants (26 men and 4 women) were enrolled in a prospective, randomized, double-blind, controlled study. Participants were randomly assigned to a Manipulation or Sham group. Muscle activity was recorded using surface EMG, and isometric strength was assessed with a Biodex dynamometer. EMG signals were normalized to session-specific maximal voluntary isometric contractions (MVIC) and expressed as %MVIC for amplitude and median frequency. Baseline differences were examined with Welch’s t-tests. The primary analysis used analysis of covariance (ANCOVA) on POST values adjusted for PRE, with partial eta squared (η²_p) as an effect size. Change-score comparisons (Δ = POST − PRE) and Hedges-corrected Cohen’s d were reported as sensitivity analyses. False discovery rate (FDR) correction was applied across outcomes. Results: No significant between-group differences were observed after adjustment for baseline in any %MVIC amplitude or median frequency outcome (p > 0.05, all FDR-adjusted q > 0.05). Within-group analyses showed small, nonsignificant changes in both groups, with the Manipulation group tending toward slightly greater increases in peroneus longus %MVIC amplitude (Δ = +3.1%, p = 0.033, d = 0.79, not significant after FDR correction). Descriptive data indicated similar PRE and POST values across groups for all muscles. Conclusions: When EMG activity is expressed relative to MVIC and baseline differences are controlled, a single superior ankle traction manipulation does not produce statistically significant acute changes in peroneus longus, gluteus medius, or tensor fasciae latae activity compared with a sham procedure. These findings suggest that previously reported differences may have reflected unadjusted baseline variability rather than true intervention effects. Full article

Background/Objectives: Despite a substantial duration of recovery following the modified Broström procedure (MBP), many individuals do not entirely recover their preinjury sports performance. Return to sports (RTS) can be affected by multiple elements apart from a patient’s motivation. This study aimed to investigate the factors influencing RTS after anatomical ligament repair for chronic ankle instability. Methods: Sixty-two patients aged under 35 who underwent the MBP were regularly monitored for up to 3 years. Of these, 51 patients (82.3%) returned to their preinjury level of sports activity (return group), while 11 patients (17.7%) complained of partial or significant limitations (non-return group). Clinical outcomes were measured by the Foot and Ankle Outcome Score (FAOS) and the Foot and Ankle Ability Measure (FAAM). Mechanical stability was examined through physical examination and stress radiography. Peroneal strength was evaluated with an isokinetic dynamometer. Static and dynamic postural control abilities were tested using Biodex posturography. Results: Significant group differences were found in FAOS pain (94.7 points in the return group vs. 85.1 points in the non-return group; p = 0.004) and sports (91.2 vs. 78.8 points; p < 0.001) subscales. In the FAAM, the sports activity subscale also showed significant disparities (90.5 vs. 77.4 points, p < 0.001). Mechanical instability recurred in 2 patients (3.9%) in the return group and 4 patients (36.4%) in the non-return group, indicating a significant difference (p < 0.001). No notable differences were identified in stress radiography values or peroneal strength measurements. Posturographic evaluation showed that static postural control ability (overall stability index) did not differ significantly between the groups (1.22 in the return group vs. 1.43 in the non-return group); however, dynamic postural control ability differed substantially (1.41 vs. 2.33, p = 0.002). Conclusions: Residual pain, recurrence of mechanical instability, and insufficient recovery of dynamic postural control ability were associated with the return to preinjury level of sports activity after the MBP. Comprehensive rehabilitation protocols should address these factors to facilitate optimal postoperative sports participation. Full article

Background/Objectives: Although considerable progress has been made in understanding lateral ankle sprains (LAS) and chronic ankle instability (CAI), recurrent injury rates remain high. This highlights the need to explore additional contributors such as comprehensive lower-limb gait analysis, including multisegmented foot models and proximal joint kinematics and strength. This study aimed to assess multisegmented foot and lower-limb kinematics throughout the gait cycle in individuals with CAI compared to healthy controls. Additionally, associations between hip abductor strength and frontal plane ankle kinematics were examined. Methods: Fifty males (25 with CAI and 25 healthy controls) participated in this cross-sectional study. Gait analysis was conducted using a BTS SMART 3D motion capture system to assess multisegmented foot and proximal joint kinematics. Isometric hip strength was measured using a Biodex dynamometer. Statistical Parametric Mapping (SPM) was used to assess group differences, and correlations were calculated between hip abductor strength and ankle kinematics. Results: The CAI group demonstrated significantly greater calcaneus abduction relative to the shank in the transverse plane between 88% and 93% of the gait cycle (MD = −3.50°, 95% CI [−5.60, −1.40], d = −0.95, p = 0.037). No other statistically significant between-group differences in hip, knee, or foot segment kinematics were detected. Furthermore, correlations between hip abductor strength and ankle frontal plane kinematics were not significant. Conclusions: Males with CAI demonstrated altered rearfoot kinematics in the transverse plane during the terminal swing phase. The multisegmented foot model was valuable in detecting subtle deviations and emphasized the importance of including the swing phase. Hip abductor strength was not associated with ankle kinematics, suggesting that its potential role in CAI may involve other mechanisms. These findings may support clinical gait assessment and rehabilitation planning by highlighting the importance of evaluating all foot segments and the entire lower limb, rather than focusing solely on the ankle joint. Segment-specific deviations, particularly those emerging during the swing phase, may help guide targeted interventions aimed at improving foot positioning in males with CAI. Full article

Study Design: Pilot randomized clinical trial. Objective: To examine the effect of electrically evoked muscle hypertrophy on indices of spasticity, as measured by Biodex after spinal cord injury (SCI). Setting: Medical research center. Methods: Thirteen males with chronic SCI were randomized into sixteen weeks of either surface neuromuscular resistance training (NMES-RT) + testosterone treatment (TT) (n = 7) or a TT-only group (n = 6). A Biodex isokinetic dynamometer was used to measure knee extensor and flexor muscle spasticity at the beginning (baseline; BL) and at the end (post-intervention; PI) of 16 weeks. The passive tension of the right knee extensor and flexor muscle groups were evaluated at angles of 5°, 30°, 60°, 90°, 180°, and 270° per second (sec). Dual energy X-ray absorptiometry and magnetic resonance imaging were used to measure leg lean mass and thigh muscle cross-sectional areas (CSAs). Results: Robust muscle hypertrophy was noted in leg lean mass [11%, p = 0.023] as well as whole thigh [17%, p = 0.001] and knee extensor muscle [28%, p = 0.001] CSAs in the NMES-RT+TT compared to the TT-only group. There was no difference in extensor or flexor spasticity between the NMES-RT+TT or TT-only groups at different angular velocities following 16 weeks of intervention. Collapsing the extensor passive torques indicated an (24–28%) increase (p < 0.004) in response to angular velocities at BL and following PI measurements [180 deg/sec (23%; p = 0.03) and 270 deg/sec (32%; p = 0.009)] compared to 5 deg/sec. The extensor slope showed a non-significant (p > 0.05) decrease of 15–28% across all angular velocities. The catch-AB slopes were non-significantly lower in the TT-only group compared to the NMES-RT+TT at higher speeds [90 deg/sec and 270 deg/sec] and attained a trend towards lower passive torque at 180 deg/sec [180 deg/sec: 15.5%, p = 0.05]. Conclusions: Evoking skeletal muscle hypertrophy did not increase spasticity indices at different angular velocities following sixteen weeks of NMES-RT+TT or TT in persons with chronic SCI. Augmenting muscle hypertrophy is likely to attenuate the hyper reflexive slope of the extensor spasticity. The findings may suggest that evoking muscle hypertrophy following NMES-RT does not increase indices of spasticity after SCI. The clinical implications are highly important in managing spasticity after SCI. Full article

Background and Objectives: A prominent area of research in adolescent ACL reconstruction (ACLR) involves graft selection, with particular interest in the quadriceps tendon (QT) as an alternative to hamstring tendon (HT) autografts, although comparative studies on muscle strength outcomes and patient satisfaction in adolescents remain limited. This study aims to evaluate the influence of QT and HT autografts on muscle strength and satisfaction outcomes post-ACLR in adolescents. Methods: This prospective study was conducted at the Lithuanian University of Health Sciences, enrolling 68 patients aged 12–17. ACLRs were performed using QT or HT autografts. Muscle strength was assessed using an isokinetic dynamometer (Biodex), while patient satisfaction was evaluated through IKDC, Lysholm, and ACL-RSI surveys preoperatively and 12 months postoperatively. Results: 54 patients (24 QT and 30 HT) completed the study. The data are non-parametric and are presented as median (IQR). Isokinetic measurements indicated that QT harvesting led to significantly lower extension strength compared to HT 6 months (p = 0.019) and 12 months post-op (p < 0.001) but showed better H/Q ratios 6 months (p = 0.019) and 12 months post-op (p < 0.001). There was no significant difference between the QT and HT groups in ACL-RSI and Lysholm scores. IKDC scores were significantly higher in the HT group (p = 0.009). Conclusions: QT autografts provide favorable H/Q ratios, yet they exhibit weaker extension strength and lower satisfaction outcomes compared to HT. These results suggest a need for individualized rehabilitation protocols and further research to optimize ACLR graft selection for adolescents. Full article

Objective: To evaluate changes in the isokinetic concentric moment of the knee extensors and the moment–velocity curve during the application of no BFR compared to superimposed BFR. Methods: A total of 37 physically active adults [33.73 (10.96) years; 11 females] performed three sets of isokinetic concentric knee extensions, each including three angular velocities (300°/s, 210°/s, and 120°/s; BIODEX dynamometer). BFR at 40% (BFR40) and 80% (BFR80) of the maximal pressure occlusion (MPO) were applied randomly after an equal control protocol without BFR (BFR0). Results: No significant differences were found for any interaction between the BFR condition and angular velocity (p > 0.05); 109.78 ± 32.90 vs. 71.24 ± 11.18, 116.68 ± 27.29 vs. 74.40 ± 15.11, and 113.91 ± 28.43 vs. 72.95 ± 13.76 Nm at 300°/s; 137.60 ± 35.27 vs. 88.85 ± 15.23, 135.40 ± 33.04 vs. 86.32 ± 17.38, and 132.68 ± 31.99 vs. 85.39 ± 16.25 Nm at 210°/s; 177.62 ± 41.40 vs. 114.72 ± 20.10, 166.40 ± 45.39 vs. 198.14 ± 21.80, and 162.60 ± 40.10 vs. 109.09 ± 18.90 Nm at 120°/s, for BFR0, BFR40, and BFR80, respectively. There were significant differences in the interactions by gender. Conclusions: Superimposed application of BFR at 40% MPO and 80% MPO during an isokinetic knee extension did not cause any acute change in the ability to produce maximal moment or power. The use of BFR may not generate an ergogenic effect that is sufficient to cause acute changes in force production. Full article

Background: Over the season, competitive swimmers experience a progressive imbalance in rotator cuff strength, predisposing them to a significant risk factor for a swimmer’s shoulder injury. Objectives: Verify the effectiveness of two 12-week preventive programs on the shoulder rotators’ peak torque and conventional/functional ratios. Design: A care provider- and participant-blinded, parallel, randomized controlled trial with three groups. Participants: Competitive swimmers aged 16 to 35 years with no prior clinical issues related to their shoulders. Interventions: Twice a week, over 12 weeks, the two experimental groups performed five exercises where the only difference was executing the program with weights or elastic bands, and the control group performed a sham intervention. Main outcome measures: The concentric and eccentric peak torque of the internal and external rotators of the dominant shoulder were assessed before and after the intervention using an isokinetic dynamometer Biodex System 3, at 60°/s, 120°/s, and 180°/s. Results: Among the experimental groups, only one test indicated a reduction (p ≤ 0.05) in rotator peak torque, while the control group showed a decrease (p ≤ 0.05) in five tests. Swimmers who completed the prevention programs demonstrated less imbalance in conventional/functional ratios than controls. Conclusions: Implementing a 12-week preventive program minimizes the progressive shoulder rotational imbalance over the season in competitive swimmers. Clinical Trial Registration number: NCT06552585. Full article

Background and Objective: Stroke, a major contributor to long-term disability worldwide, often results in significant impairments in motor function. These impairments can include weakness, impaired balance, and decreased coordination, which can have a significant influence on one’s quality of life and independence. Finding an effective protocol for rehabilitation to improve these points will decrease the impact of stroke and its coast of rehabilitation. Materials and Methods: This study was conducted to assess the effect of lower limb plyometric exercises on strength, postural control, and risk of falling in stroke patients. Materials and Methods: This study involved 40 chronic left stroke patients randomly divided into two equal groups. The experimental group participated in a 12-week supervised plyometric training program, while the control group received conventional physical therapy program. Lower limb muscle strength was measured using a handheld dynamometer, and balance and fall risk were assessed via the Biodex Balance System (BBS). These measurements were conducted before and after the intervention period to evaluate treatment effects. Results: The results of this study demonstrated significant improvements in muscle strength and balance parameters among stroke patients who underwent plyometric exercise compared to those receiving a conventional program. The plyometric group exhibited significantly greater increases in knee extension strength (p < 0.05), hip abduction strength (p < 0.05), ankle dorsiflexion strength (p < 0.05), and ankle eversion strength (p < 0.05). Furthermore, the plyometric group showed significant improvements in overall stability (p < 0.05), mediolateral stability (p < 0.05), and anteroposterior stability (p < 0.05), as measured by the Biodex Balance System (BBS). Conclusions: The results of this study suggest that plyometric exercise may be an effective intervention for decreased risk of falling and enhancing muscle strength and balance during recovery from stroke. Full article

Strength assessment is one of the main fields in sports performance, physical rehabilitation, physical activity, and health. We aimed to compare maximal voluntary isometric contractions (MVICs) and paired voluntary isometric contractions (VICs) of knee extensors between an isokinetic dynamometer (BIODEX) and a portable and lightweight device (DINABANG). From 19 volunteers (age: 28.7 ± 7 years; body mass: 72 ± 10 kg; and height: 173 ± 7 cm) we obtained 114 paired MVIC measures and, from the force–time curves of these repetitions, 22,507 paired VIC measures of knee extensors. We observed “excellent” repeatability for MVICs (ICC:1.00; p < 0.001) between BIODEX (247 ± 79.5 Nm) and DINABANG (247 ± 74.8 Nm), with “trivial” effect (mean difference: 0.12 Nm (0.02%); 95%CI: −0.13 to 0.23 Nm; p = 0.606; d = 0.048). Bland–Altman plots revealed high accuracy for MVIC (bias: 0.12 Nm) and consistent distribution (precision) inside the limits of agreement (−4.81 to 5.06 Nm) and respective 95%CI. “Excellent” repeatability was also observed for VICs (ICC:1.00; p < 0.001) between BIODEX (219 ± 84.1 Nm) and DINABANG (218 ± 84.0 Nm), with “trivial” effect (0.24 Nm (0.11%); 0.08 to 0.11 Nm; p < 0.001; d = 0.100). Bland–Altman plots revealed high accuracy for VICs (bias: 0.24 Nm) and consistent distribution (precision) inside the limits of agreement (−4.5 to 4.9 Nm) and respective 95%CI. DINABANG is accurate, precise, and reliable in torque measurement. Full article

Background and Objectives: Biodex System^® is an advanced dynamometer used for testing various biomechanical parameters of muscles. Test outcomes allow for the identification of muscle pathology and consequently lead to a clinical diagnosis. Despite being widely used for the testing and rehabilitation of the human musculoskeletal system, no universal and acceptable protocol for wrist examination has been proposed for patients with wrist pathology. In this study, the authors aim to identify the most appropriate protocol for testing the biomechanical parameters of flexors and extensors of the wrist. Materials and Methods: A group of 20 patients with symptomatic tennis elbow and 26 healthy volunteers were examined using three different protocols: isokinetic, isometric and isotonic. Protocol order for each study participant was assigned at random with a minimum of a 24 h break between protocols. All protocol parameters were set according to data obtained from a literature review and an earlier pilot study. Following completion of each protocol, participants filled out a questionnaire-based protocol, assessing pain intensity during the exam, difficulty with exam performance and post-exam muscle fatigue. Results: The isotonic protocol showed the best patient tolerance and the highest questionnaire score. There was a significant difference (p < 0.05) between the three protocols in average pain intensity reported by study participants. All participants completed the isotonic protocol, but not all patients with symptomatic tennis elbow were able to complete the isometric and isokinetic protocols. The isotonic protocol was deemed “difficult but possible to complete” by study participants. Conclusions: The isotonic protocol is most suitable for testing the flexors and extensors of the wrist. It gives the most biomechanical data of all protocols, is well tolerated by patients and rarely causes pain during examination even in symptomatic participants. Full article

Background and Objectives: Lean body mass loss after bariatric surgery (BS) is remarkable, despite an effective long-term mass reduction and significant declines in comorbidities. A person’s functional capacity is adversely affected when their skeletal muscle strength declines by up to 30%. This study aimed to assess the isokinetic trunk muscle strength and fatigue rate in individuals after BS. Materials and Methods: This study included fifty-eight patients, both male and female, ranging in age from 19 to 45. Twenty-seven individuals had BS and twenty-seven healthy people served as the control group. The primary outcomes were the measurement of the concentric and eccentric isokinetic muscle strength of the trunk flexor and extensor muscles. An isokinetic dynamometer (Biodex Rehabilitation and Testing System 3) was used for the assessment of the isokinetic muscle strength. Noraxon EMG was used to determine a secondary outcome, which was the median frequency slop (MF/time) and root mean square slop (RMS/time) of the lumbar erector spinea muscle at 50% of the Maximum Voluntary Isometric Contraction (MVIC). Outcome measures were assessed for both groups. Results: Compared to the control group, the bariatric group showed a lower mean value of both concentric and eccentric isokinetic muscle strength for the flexor and extensor trunk muscles (p < 0.05). In terms of the EMG fatigue rate, the RMS slope increased significantly more than that of the control group, while the MF slope decreased (p > 0.05). Conclusions: The current study found that, in comparison to the healthy subjects, the BS group showed reduced levels of fatigue and isokinetic strength in the trunk muscles. Based on these results, it is recommended that individuals who underwent BS take part in tailored rehabilitation programs to avoid potential musculoskeletal issues in the future. Full article

Background: Evidence suggests that COVID-19 infection can cause lasting health consequences. Multidisciplinary rehabilitation services have been recommended to reduce the sequalae. However, the effectiveness of physical exercise interventions remains insufficiently documented. The aim of this study was to develop and implement a specific and well-tolerated protocol-based intervention to reduce muscle weakness in older adults impacted by COVID-19. Methods: Forty-six older adults were randomized into intervention and control groups. Isometric and isokinetic strength assessments were conducted for selected muscle groups using a JBA Staniak^® torquemeter and Biodex System 3 dynamometer. Functional abilities were evaluated with the Time Up and Go test and Chair Stand Tests. Results: Men in the intervention group demonstrated a significant improvement in static conditions for knee flexors (KFs), trunk extensors (TEs) and trunk flexors (TFs) and in dynamic conditions for knee extensors (KEs). Women in the intervention group showed a significant improvement in static conditions for EFs, KFs, TEs and TFs and in dynamic conditions for a KE and a KF. The interaction GROUP × TESTING SESSION was significant for the Chair Test (s) and Chair Test (n). Conclusions: Our results demonstrate the effectiveness of a well-tolerated, protocol-based approach that can be used to diminish long-lasting functional deficits in post-COVID survivors. Full article

Background: the study determined the validity and reliability of measurements obtained using the portable traction dynamometer (PTD) (E-Lastic, E-Sports Solutions, Brazil) and the reproducibility between evaluators (precision) in the evaluation of the isometric muscle strength of the knee extensors of healthy male adults, compared to measurements obtained with the “gold standard” computerized dynamometer (CD) (Biodex System 3, Nova York, NY, USA). Methods: we evaluated sixteen recreationally active men (29.50 ± 7.26 years). The test–retest reliability of both equipment to determine quadriceps strength, agreement analysis, and the minimal important difference were verified. Results: excellent test–retest interrater reliability was observed for absolute and relative measurements, with a low absolute error for both sets of equipment and excellent validity of the PTD against the CD, as verified by linear regression and Pearson’s correlation coefficient. Conclusions: PTD is a valid and reliable instrument for assessing the isometric strength of knee extensors, with results similar to the isometric CD “gold standard”. Full article