Functional Anatomy of the Hamstring Muscle and Its Correlation with the Various Yogic Postures: A Narrative Review

Yoga is believed to be a safe practice; nonetheless, as the number of yoga practitioners has grown, so has the incidence of yoga-related injuries. Overall, lower extremity injuries comprised 64% of total injuries; specifically, the hip, hamstring, knee, ankle, feet and toe. Although a few research studies have quantified the hamstring muscle activities in various yoga asanas, evidence correlating it to functional anatomy is scarce. Therefore, the objective of this narrative review is to examine the literature and analyse hamstrings activity and its relationship to yogic postures, as well as yoga-related injuries, to establish which poses provide the most risk of damage, and to suggest injury-prevention techniques. The following electronic databases were used to conduct the literature search: Cochrane Library, PubMed, Google Scholar, EMBASE, and Web of Science. hamstring muscle injuries OR yoga and rehabilitation OR intervention AND electromyography was among the search phrases utilized. Such information is important for yoga teachers, yoga therapists to help selecting yoga posture for hamstring muscle imbalance condition and avoiding posture to prevent hamstring muscle injury.

Estimation Method for Optimal Length of Hamstring Muscles in vivo / 医用生物力学

Objective To build a method for calculating the optimal length of hamstring muscles in vivo, and make comparison with other indirect parameters which represent the optimal length. Methods By synchronously recording knee flexion torque and kinematic data, the musculoskeletal model of lower limbs was built to obtain hamstring strength and muscle length, and to further calculate the optimal length of hamstring muscles. Results Flexion angle at peak knee flexion torque was significantly greater than that at peak hamstring strength and their correlation coefficient was 0.741. The optimal lengths of each bi-articulated hamstring muscles were significantly greater than the corresponding muscle lengths during standing and their correlation coefficients was low. Conclusions The established estimating method for optimal length of hamstring muscles provided references for future studies on injury mechanism and risk factors. Flexion angle at peak knee flexion torque could partly represent the optimal length of hamstring. It is not suggested that hamstring muscle length during standing should be used as an approximation of hamstring optimal length.

Effect Of Padahastasana In Improving Hamstring Muscle Flexibility Among Young Adults

CONTEXT: Hamstring muscle is actively involved in various activities of daily living like walking, stair climbing etc. The flexibility of Hamstring muscle is found to be commonly compromised among various age groups. This may be due to ineffective use of the muscle to full extensibility in routine activities. Padahastasana is a yogasana in standing position which induces maximum stretch to posterior structures of thigh including Hamstring muscle. AIMS:This study aims to investigate the effect of Padahastasana in improving flexibility of Hamstring muscle SETTINGS AND DESIGN:Experimental Design with random sampling method conducted among 20 subjects. METHODS AND MATERIAL: Subjects were recruited for the study based on inclusion and exclusion criteria. Hamstring flexibility was assessed using sit and reach box - a standardized tool to measure Hamstring flexibility. The selected subjects were taught the technique of Padahastasana and practiced for twelve weeks – six times in a day and minimum five days per week. After twelve weeks of practice, hamstring flexibility was assessed using sit and reach box. STATISTICALANALYSIS:Analysis was conducted using't' test Results: The study showed significant improvement (t value – 13.01 at p≤0.05) in Hamstring muscle flexibility by performing 12 weeks Padahastasana practice. CONCLUSIONS: Padahastasana can be recommended to prevent and treat Hamstring muscle tightness

Comparative effect of ultrasound therapy versus static stretching on the extensibility of hamstring muscles.

Background: Many peoples suffer from tight hamstring muscles which predispose them to injury when they engage in vigorous physical activity. Ultrasound therapy have been used to enhance the effectiveness of muscle stretching, but evidence supporting their benefits is confusing. Aims & Objective: The Objective of the current study is to compare the immediate effect of ultrasound (US) and static stretching exercise on the extensibility of hamstring muscles. Materials and Methods: Forty normal Participants between the ages of 18 and 21 who demonstrated at least 15 degrees of unilateral hamstring tightness. They were randomly assigned to 1 of 4 groups: (1) ultrasound therapy; (2) 30 second static stretching; (3) ultrasound therapy and 30 second static stretching; and (4) control group which don't receive any treatment. The Main Outcome Measure was Hamstring extensibility measured by active knee extension test (AKE). Differences were compared within groups and between treatment groups using one way analysis of variance. Results: There was a significant difference between pre and post-treatment in all treatment groups (p<0.05), but there was no significant difference regarding the control group (p>0.05). 30 second Static stretching exercise followed by 1 MHZ ultrasound therapy showed a significant increase in AKE when compared by sole treatment or control group (p<0.05). Conclusion: The use of ultrasound therapy followed by 30 second static stretching enhance the flexibility of hamstring muscle. This results can aid in designing physical therapy protocols for similar conditions.

Localization of the Motor Nerve Branches and Motor Points of the Hamstring Muscles and Triceps Surae Muscle

OBJECTIVE: To identify the precise locations of the motor branches and motor points of hamstring and triceps surae muscles to the bony landmarks. METHOD: Twenty-eight limbs of 14 adult cadavers were anatomically dissected. The adult cadavers were selected randomly without regard to gender and age. The cadravers which were unable to obtain a neutral position or which received a trauma to the posterior thighs or the lower legs were excluded from the study. The number and location of the motor branches and motor points from sciatic nerve to each hamstirng muscles and from tibial nerve to each triceps surae muscles were identified related to the bony landmarks. Bony landmarks were ischial tuberosity, medial and lateral epicondyles of femur, and medial and lateral malleolli of tibia. The length of femur was defined as the distance from the ischial tuberosity to the intercondylar line of femur and the length of lower leg was defined as the distance from the intercondylar line of femur to the intermalleolar line of tibia. The locations of the muscular branches and the motor points were expressed as the percentage of the length of femur and lower leg. RESULTS: One muscular branch from the sciatic nerve to the semimembranosus muscle and from the posterior tibial nerve to the soleus muscle, and one or two muscular branches to the biceps femoris, semitendinosus, and semimembranosus, medial gastrocnemius, lateral gastrocnemius and soleus muscle were located at 23.0+/-5.7%, 21.0+/-10.5%, 25.0+/-10.3% of the femur from the ischial tuberosity and 2.0+/-6.2%, 4.0+/-3.3% and 10.0+/-3.3% of the lower leg from the intercondylar line of femur. There were one to four motor points in the hamstring and triceps surae muscles. The motor points of biceps femoris, semitendinosus and semimembranosus were located at 33.0+/-7.8%, 28.0+/-14.5% and 48.0+/-19.0% of the femur. The motor points of the medial gastrocnemius, lateral gastrocnemius and soleus were located in 5.0+/-0.6%, 10.0+/-3.0% and 18.0+/-4.3% of the lower leg below the intercondylar line of femur. CONCLUSION: The identification of the locations of muscular branches and motor points related to the bony landmarks from this study would increase the accuracy of the motor branch blocks or motor point blocks to the hamstrings and triceps surae muscles.

Accessory Hamstring Muscle: A Case Report / 대한정형외과학회잡지

Accessory hamstring muscle is rare in incidence. In the popliteal region, it often simulates soft tissue tumor since it may be manifest as popliteal swelling. We experienced a case of accessory hamstring muscle which simulated popliteal tumor on physical examination.