Biomechanical Characteristics of the Knee Joint during Gait in Obese versus Normal Subjects

Knee osteoarthritis (OA) is a growing source of pain and disability. Obesity is the most important avoidable risk factor underlying knee OA. The processes by which obesity impacts osteoarthritis are of tremendous interest to osteoarthritis researchers and physicians, where the joint mechanical load is one of the pathways generally thought to cause or intensify the disease process. In the current work, we developed a hybrid framework that simultaneously incorporates a detailed finite element model of the knee joint within a musculoskeletal model to compute lower extremity muscle forces and knee joint stresses in normal-weight (N) and obese (OB) subjects during the stance phase gait. This model accounts for the synergy between the active musculature and passive structures. In comparing OB subjects and normal ones, forces significantly increased in all muscle groups at most instances of stance. Mainly, much higher activation was computed with lateral hamstrings and medial gastrocnemius. Cartilage contact average pressure was mostly supported by the medial plateau and increased by 22%, with a larger portion of the load transmitted via menisci. This medial compartment experienced larger relative movement and cartilage stresses in the normal subjects and continued to do so with a higher level in the obese subjects. Finally, the developed bioengineering frame and the examined parameters during this investigation might be useful clinically in evaluating the initiation and propagation of knee OA.

Determinants of whole-body maximal aerobic performance in young male and female athletes: The roles of lower extremity muscle size, strength and power

This study sought to determine whether lower extremity muscle size, power and strength could be a determinant of whole-body maximal aerobic performance in athletes. 20 male and 19 female young athletes (18 ± 4 years) from various sporting disciplines participated in this study. All athletes performed a continuous ramp-incremental cycling to exhaustion for the determination of peak oxygen uptake (V˙O2peak: the highest V˙O2 over a 15-s period) and maximal power output (MPO: power output corresponding to V˙O2peak). Axial scanning of the right leg was performed with magnetic resonance imaging, and anatomical cross-sectional areas (CSAs) of quadriceps femoris (QF) and hamstring muscles at 50% of thigh length were measured. Moreover, bilateral leg extension power and unilateral isometric knee extension and flexion torque were determined. All variables were normalised to body mass, and six independent variables (V˙O2peak, CSAs of thigh muscles, leg extension power and knee extension and flexion torque) were entered into a forward stepwise multiple regression model with MPO being dependent variable for males and females separately. In the males, V˙O2peak was chosen as the single predictor of MPO explaining 78% of the variance. In the females, MPO was attributed to, in the order of importance, V˙O2peak (p < 0.001) and the CSA of QF (p = 0.011) accounting for 84% of the variance. This study suggests that while oxygen transport capacity is the main determinant of MPO regardless of sex, thigh muscle size also has a role in whole-body maximal aerobic performance in female athletes.

Effects of Kinesio Taping with Squat Exercise on the Muscle Activity, Muscle Strength, Muscle Tension, and Dynamic Stability of Softball Players in the Lower Extremities: A Randomized Controlled Study

Background and purpose: Knee injuries are common among female softball players, and the stability of the lower extremities and the strength of the knee are essential factors for them. The purpose of this study was to investigate the effect of Kinesio taping with squat exercise (KTSE) on lower extremity muscle activity, muscle strength, muscle tone, and dynamic stability of softball players. Methods: In this study, 40 softball players were randomly assigned to the KTSE group and sham taping with squat exercise (SKTSE) group. All subjects were tested three times a week for 6 weeks, i.e., for a total of 18 times. To evaluate the lower-extremity muscle activity, muscle strength, and muscle tone of the lower extremities, as well as dynamic stability, we used Noraxon Mini DTS, a digital muscular meter from JTech Medical, MyotonPRO, and the side hop test (a clinical evaluation method), respectively. These items were measured before the experiment and 6 weeks after the start of the experiment. Results: Both groups showed significant differences in lower-extremity muscle activity, muscle strength, muscle tone, and dynamic stability (p < 0.05). After the experiment, significant effects on lower-extremity muscle activity, muscle strength, muscle tone, and dynamic stability were observed in the KTSE group compared with in the SKTSE group (p < 0.05). Conclusions: KTSE did not have a negative effect on all items of the functional performance test. KTSE improved lower-extremity muscle activity, muscle strength, muscle tone, and dynamic stability.

Ratio of maximum hamstring torque to maximum quadriceps torque in professional basketball and soccer players

Purpose: The aim of the study was to determine the differences between football players and basketball players in the mean absolute values ​​of maximum torque flexors and extensors, ratio of maximum hamstring torque to maximum quadriceps torque dominant (DOM) non-dominant (ND) leg and differences in bilateral imbalance of flexor muscles and knee extensors. Material and methods: The research included a sample of 39 professional athletes. The first subsample included 19 professional basketball players while the second subsample included 20 professional soccer players. Results: Based on the results of the torques of the extensors in the knee joint of the DOM and ND legs, it was established that there is no statistically significant difference between basketball players and football players. However, a statistically significant difference was found in the torque flexors of the knee joint DOM (p≤0.01) and ND (p≤0.00) of the leg between basketball players and football players. On the other hand, the results of the research indicate that the difference between basketball players and football players in the ratio of Hamstrings peak torque to Quadriceps peak torque was recorded only in the ND leg (p≤0.02), while the difference in the DOM leg is not statistically significant. The results of our study indicate that basketball players have a higher percentage of imbalances compared to football players, especially in m. hamstrings. Conclusion: This study provides normative data on populations specific to soccer and basketball, but does not provide evidence of the ability of the isokinetic assessment of lower extremity muscle strength to predict injuries to football players and basketball players.

Allogeneic haematopoietic stem cell transplantation—clinical outcomes: impact of leg muscle strength

ObjectivesMuscle strength decline is reported to predict mortality in many cancers. However, there is little knowledge of the relation between muscle strength decline and clinical outcomes of allogeneic haematopoietic stem cell transplantation (allo-HSCT). This study aimed to determine the impact of pre-transplant lower extremity muscle strength (LEMS) on post-transplant overall survival (OS) and non-relapse mortality (NRM).MethodsIn this retrospective cohort study, 97 adult patients underwent allo-HSCT during 2012–2020. LEMS was defined as knee extension force divided by patient’s body weight. The patients were divided into low and high LEMS groups based on pre-transplant LEMS. OS was measured using the Kaplan-Meier method and the Cox proportional hazards model. The cumulative incidence of NRM was evaluated using the Fine and Gray method, with relapse considered as a competing risk event.ResultsProbability of OS was significantly lower in the low LEMS groups (HR 2.48, 95% CI 1.20 to 5.12, p=0.014) than in the high LEMS group on multivariate analysis. Five-year OS was 25.8% and 66.4% in the low and high LEMS groups, respectively. Risk of NRM was significantly higher in the low LEMS group (HR 4.49, 95% CI 1.28 to 15.68, p=0.019) than in the high LEMS group. The cumulative incidence of NRM was 41.4% and 11.1% in the low and high LEMS groups, respectively.ConclusionsPre-transplant LEMS was a significant factor in predicting OS and NRM.

Penerapan Latihan Rom Aktif Terhadap Kekuatan Otot Ekstremitas Bawah Pada Lansia Pasca Stroke

Stroke is a brain disorder that occurs due to damage to part of the brain caused by blocked blood vessels so that the flow of oxygen is not met properly. Stroke can cause death, paralysis, impaired speech, and decreased consciousness. The purpose of this case study was to increase lower extremity muscle strength by using ROM exercises. The method used was a case study by providing nursing care to two elderly post-stroke using Active Rom exercises. The results of this case study before doing active ROM on client I experienced a decrease in muscle strength with a percentage of 25 degrees 2 and client II experienced a decrease in muscle strength with a percentage of 25 degrees 2. After doing active ROM there was an increase in muscle strength in client I with a percentage of 75 degrees 4 and on client II with a percentage of 50 degrees 3. This case study can be said that the application of active range of motion (ROM) exercises can increase lower extremity muscle strength in the elderly after stroke. This case study is a consideration for nurses and other health workers to apply active ROM exercises in post-stroke patients.Key words : Gerontic Nursing Care, Elderly Post-Stroke, Active ROM. AbstrakStroke adalah gangguan pada otak yang terjadi karena adanya gangguan kerusakan pada sebagian otak disebabkan karena pembuluh darah yang tersumbat sehingga aliran oksigen tidak terpenuhi dengan baik. Penyakit stroke dapat menyebabkan kematian, kelumpuhan, gangguan berbicara, dan menurunkan kesadaran. Tujuan dari studi kasus ini adalah untuk meningkatkan kekuatan otot ekstremitas bawah dengan menggunakan latihan ROM. Metode yang digunakan adalah studi kasus dengan memberikan asuhan keperawatan pada dua lansia pasca stroke dengan menggunakan latihan Rom Aktif. Hasil studi kasus ini sebelum dilakukan ROM aktif pada klien I mengalami penurunan kekuatan otot dengan presentase 25 derajat 2 dan klien II mengalami penurunan kekuatan otot dengan presentase 25 derajat 2. Setelah dilakukan ROM aktif terjadi peningkatan kekuatan otot pada klien I dengan presentase 75 derajat 4 dan pada klien II dengan presentase 50 derajat 3. Kesimpulan studi kasus ini dapat disimpulkan bahwa penerapan latihan range of motion (ROM) aktif dapat meningkatkan kekuatan otot ekstremitas bawah pada lansia pasca stroke. Studi kasus ini sebagai pertimbangan bagi perawat dan tenaga kesehatan lain untuk menerapkan latihan ROM aktif pada pasien pasca strokeKata kunci: Asuhan Keperawatan Gerontik, Lansia Pasca Stroke, ROM aktif.

Feasibility of the modified 30-second sit-to-stand test in an isolation ward of moderate COVID-19

BACKGROUND The recovery after prolonged immobilization during hospitalization because of COVID-19 is the primary goal of moderate to severe COVID-19 rehabilitation. Lower extremity muscle function assessment after immobilization is needed before starting mobilization. Hence, this study aimed to evaluate the feasibility of the modified 30-second sit-to-stand test (m30STS) as one of the prospective tools of functional capacity assessment in moderate COVID-19. METHODS This cross-sectional study recruited the subjects consecutively. All eligible subjects with oxygen saturation (SaO2) ≥95% with or without oxygen supplementation performed the m30STS following the Bohannon’s guidelines. The score of m30STS was calculated based on the number of stands completed within 30 sec. A higher score of the m30STS indicated better lower extremity function. RESULTS Mean score of m30STS was 13.3. No subjects had oxygen desaturation or increased heart rate, and no fall incidents occurred. CONCLUSIONS The m30STS is feasible and safe to evaluate lower extremity for moderate COVID-19 patients with SaO2 >95%. The absence of oxygen desaturation and increase in heart rate showed no increased oxygen consumption during the test.

Combining Exercise, Protein Supplementation and Electric Stimulation to Mitigate Muscle Wasting and Improve Outcomes for Survivors of Critical Illness - the ExPrES Study

Background: The combination of neuromuscular electrical stimulation (NMES) with high protein supplementation (HPRO) to preserve muscle mass and function has not been assessed in ICU patients. We compared the effects of a multimodal intervention combining NMES and HPRO with mobility and strength rehabilitation program (NMES+HPRO+PT) to standardized ICU care (SC). Methods: Over 14 days the SC group received usual critical care and rehabilitation while the NMES+HPRO+PT received 30 minutes NMES twice daily for 10 days applied to the quadriceps and dorsiflexors bilaterally and a mean 1.3±0.4 HPRO g/kg body weight in addition to SC. Nonresponsive patients received passive exercises and once responsive were encouraged to exercise actively. Primary outcome measures were muscle volume and cross-section area (CSA) measured using CT-imaging. Secondary outcomes included nutritional status, nitrogen balance, effect on delirium, and days on mechanical ventilation (MV).Results: On day 14, the NMES+HPRO+PT group lost significantly less muscle volume of both thighs and lower legs compared to SC group. The mean combined left and right thigh CSA and volume of the NMES+HPRO+PT group was significantly larger than the SC group on day 14. The nitrogen balance of the SC group was negative throughout the study duration, while the NMES+HPRO+PT group was positive on days 5, 9, and 14. At any time during their ICU stay SC patients experienced more delirium than the PT+NMES+HPRO group (46% vs 32%, p=0.09) although not statistically significant. There were no differences between groups when comparing length of stay or days on MV. Conclusion: The combination of NMES, HPRO and PT resulted in mitigation of lower extremity muscle loss and amelioration of clinical status of patients admitted to the ICU. The value of NMES, HPRO and PT independently in the initial and ongoing care of ICU survivors beyond 14 days of admission remains to be evaluated.Trial Registration: Clinicaltrials.gov identifier: NCT3195127