Hamstring Research Articles

Immediate Effect of Hamstring Stretching on Q Angle, Flexibility, and Balance in Individuals with Hamstring Tightness

Objective: Hamstring tightness is a common problem that can affect the quadriceps angle, flexibility of knee extension, and balance. The purpose of this study was to investigate the immediate effects of passive static hamstring stretching on the quadriceps angle, knee joint range of motion (ROM), and static and dynamic balance in people with hamstring tightness.Material and Methods: A total of 52 male participants were randomly divided into two groups: a stretching group and a control group. All participants underwent a physical therapy examination before the experiment (Pre-test), including an Active Knee Extension Test, quadriceps angle (Q angle) measurement, and static balance and dynamic balance assessments. After that, the stretching group received passive static hamstring muscle stretching, while the control group received knowledge about the tightness of the hamstring muscle. After the experiment, all participants underwent a physical therapy examination using the same testing method.Results: The study found that passive static hamstring muscle stretching increased the knee extension ROM by 5.54±3.78 degrees (p-value<0.01) and decreased the Q angle by -1.85±1.46 degrees (p-value<0.01) compared to the control group. However, there were no significant differences between the groups for the balance outcomes.Conclusion: This study found that passive static hamstring muscle stretching improved knee extension and decreased the Q angle. These findings can confirm the positive effects of exercise for increasing flexibility among individuals with tight hamstrings and abnormal Q angle.

Increased global posterior tibial slope is significantly associated with higher ACL graft signal intensity on 2-Year postoperative MRI after primary ACL reconstruction using hamstring tendon autografts.

The healing and remodeling process of tendon grafts after anterior cruciate ligament (ACL) reconstruction (ACLR) has received significant attention. This study aims to identify preoperative factors associated with postoperative signal intensity of the ACL graft after primary ACLR. A total of 90 patients underwent primary ACLR using hamstring tendon autografts by the same senior surgeon between January 2013 and December 2020 were included. Patients were followed up and scheduled for a 2-year postoperative magnetic resonance imaging (MRI) scan at our institute. Concomitant injuries were confirmed by arthroscopy. Posterior tibial slope (PTS) and anterior tibial subluxation (ATS) were measured on preoperative MRI, whereas the normalized signal intensity of the ACL graft was evaluated on postoperative MRI and calculated as the ratio of the graft signal intensity to that of the patellar tendon. Multivariable linear regression models were performed to identify preoperative factors associated with the postoperative signal intensity of the ACL graft. Multivariable analyses showed that increased global PTS (GPTS) (P = 0.008) and concomitant articular cartilage injuries (P = 0.005) were associated with higher average signal intensity of the ACL graft on two-year postoperative MRI, while preoperative internal rotational tibial subluxation (IRTS) calculated as the difference between lateral ATS and medial ATS did not show a significant association. Specifically, an increased GPTS was significantly associated with higher signal intensity in the proximal section of the ACL graft (P = 0.005), whereas no significant associations were observed in the middle and distal sections. Increased preoperative GPTS was significantly associated with higher signal intensity of the ACL graft on 2-year postoperative MRI after primary ACLR, suggesting that a steep preoperative tibial slope may contribute to a suboptimal ligamentization process in hamstring tendon autografts. Level III, retrospective cohort study.

A correlation study of weak core muscles with hamstring muscles flexibility in young adults

Abstract Background Hamstring, being a two-joint muscle, tends to shorten over time, resulting in tightness, affecting performance in daily activities and is also capable of generating exaggerated posterior pelvic tilt, leading to decreased lumbar lordosis. Weak core muscles have been associated with hamstring tightness, and strengthening the core has been attempted in an effort to relax the hamstring tightness. It is believed that the hamstrings overact and over a period of time tightens, when the core is weak, to compensate for postural stability. Method Thirty-three subjects, both male and females with and without hamstring tightness, were assessed for their core endurance through McGill’s core endurance test battery. It was followed by active knee extension test to determine degree of hamstring tightness on both sides. Correlation between the two variables was statistically analyzed. Results Pearson’s correlation was used to analyze the collected data. A moderate positive but significant correlation (p = 0.02) was found between flexor endurance test and active knee extension (both sides). A weak positive but significant correlation (p = 0.05) was found between extensor endurance test and active knee extension (both sides). Correlation between the right and left lateral bridge with their respective side hamstring flexibility was negative and not significant (p = 0.916 (right lateral torso endurance); p = 0.339 (left lateral torso endurance)). Conclusion Since there is a moderate positive but significant correlation between the flexion torso endurance test and both side hamstring flexibility and a weak positive but significant correlation between extension torso endurance test and both side hamstring flexibility, the core (flexor, extensor, and lateral) should be thought of as a whole unit when strengthening in order to maintain and improve hamstring flexibility.

Comparative Analysis of Suboccipital Muscle Inhibition Technique and Static Hamstring Stretching in Normal Healthy Individuals with Hamstring Tightness: A Randomised Clinical Trial

BACKGROUNDHamstring tightness is a major contributing factor for lower back pain, lumbar spine disorders and sports related injuries. Many studies has been done to improve the flexibility of hamstring muscle by various techniques such as different stretching techniques myofascial Release Therapy, neuro-muscular therapy and Muscle Energy Technique etc. All of these technique mentioned act at the hamstring muscle level to provide its effectiveness. In a present study we aimed at to find out the effectiveness of suboccipital muscle inhibition technique for improving tightness in hamstring muscle. Hence this study is done to find out the effectiveness of applying suboccipital muscle inhibition technique on distant muscle flexibility in turn to prove the distant muscle relationship. Study is done with the aim to find whether suboccipital muscle inhibition technique can be used along with conventional methods for improving tightness of hamstring muscle.AIMTo compare the effectiveness of suboccipital muscle inhibition technique and static hamstring stretching in normal individuals with hamstring tightness.MethodsIn this comparative study total 165 individuals were screened for tightness of hamstring. Individuals who satisfied the inclusion criteria were selected from the normal healthy population. A total of 100 healthy subjects of both genders between the age of 18 and 25 were recruited in this trial. After doing block randomization subjects were assigned to two groups ,in Group A 50 subjects were given suboccipital muscle inhibition technique for 5 sessions for 5 consecutive days. Another group 50 subjects were given static stretching to both the lower limbs for 30 seconds followed by 15 seconds relaxation, for 5 sessions for 5 consecutive days.RESULTSActive knee extension test using Mann Whitney U test in both suboccipital muscle inhibition technique and static hamstring stretching group shows no difference(p=0.623) for pretreatment, while significant result immediately post treatment (0.002) and statistically significant result in baseline parameters after 5 sessions of treatment (0.000)Forward flexion distance test using Mann Whitney U test in both suboccipital muscle inhibition technique and static hamstring stretching group shows no significant difference(p=0.088) for pretreatment and also for immediately post treatment (0.893) but shows statistically significant result in baseline parameters after 5 sessions of treatment (0.009)CONCLUSIONSuboccipital muscle inhibition technique and static hamstring stretching are both effective in improving the flexibility of hamstring muscle. The Suboccipital muscle inhibition technique is more effective compared to static hamstring stretching in normal healthy individuals with hamstring tightness.

A Study to Compare the Effects of Mulligan Traction Straight Leg Raise Technique, and Propeoceptive Neuromuscular Facilitation (Hold Relax) Technique on Tightness, and Strength of Hamstring Muscle among Young Adults

Flexibility is defined as the ability of a muscle to lengthen, allowing one joint or more to move through a range of motion (ROM), and is an essential component of normal biomechanical functioning. Hamstring tightness can occur due to the sedentary lifestyle which is the main reason for postural abnormalities. Therefore, it is important to have optimal muscle flexibility for optimal performance. In this line of thought, the present study is designed to compare the effects of Mulligan Traction Straight Leg Raise Technique and Proprioceptive Neuromuscular Facilitation hold relax technique on hamstring tightness among young adults. AIM OF THE STUDY- “To compare the effects of mulligan traction straight leg raise technique and proprioceptive neuromuscular facilitation (hold relax) technique on tightness and strength of hamstring muscle among young adults”. METHODOLOGY- The total duration of the study was one and a half year. Subjects meeting the inclusion and exclusion criteria were selected in the study. A minimum of 60 subjects, both male and female with age between 18-25 years, were selected for the study and subsequently divided into three groups with minimum of 20 subjects in each group. Group A (control group) was given warm up and hot pack for 15 minutes. Groups B and C were experimental groups. Group B was given Mulligan Traction Straight Leg Raise technique in addition to warm up and hot pack. Group C was given PNF hold relax technique in addition to warm up and hot pack. The baseline data was recorded on first day (pre intervention) and on last day of second week (post intervention). All the interventions were performed once a day, five days a week for two weeks. DATA ANALYSIS- The collected data will be analysed using ANOVA and other statistical tests as appropriate (SPSS software). RESULT- The result of present study shows that PNF hold relax is more effective in improving flexibility of the hamstring muscle than Mulligan TSLR.

The Effect of the Nordic Hamstring Exercise on Hamstring Muscle Activity Distribution During High-Speed Running Estimated Using Multichannel Electromyography: A Pragmatic Randomized Controlled Trial.

To evaluate the effect of the Nordic hamstring exercise on normalized muscle activity and relative contribution of the biceps femoris long head, semitendinosus, and semimembranosus through multichannel electromyography in the late-swing phase of high-speed running. A pragmatic, 2-arm, single-center randomized controlled trial. Participants were randomly assigned to a Nordic group or control group. Dutch male basketball. Twenty injury-free players (mean age 18 ± 3 years). A 12-week Nordic hamstring exercise intervention. Level of normalized muscle activity (percentage maximal voluntary isometric contraction [%MVIC]) and relative contribution (%con) of hamstring muscles for 12 weeks. The Nordic hamstring exercise intervention did not result in significant changes for 12 weeks. For normalized muscle activity, between-group differences (compared with the control group) for 12 weeks were 11.4 %MVIC (95% confidence interval [95% CI]: -11.0, 33.8) for the biceps femoris long head, -9.4 %MVIC (95% CI: -23.3, 5.2) for the semitendinosus, and -2.7 %MVIC (95% CI: -15.8, 10.3) for the semimembranosus, P = 0.151. For relative contribution, between-group differences for 12 weeks were -6.1 %con (95% CI: -2.4, 14.6) for the biceps femoris long head, -7.0 %con (95% CI: -13.6, -0.4) for the semitendinosus, and 0.9 %con (95% CI: -9.2, 11.0) for the semimembranosus P = 0.187. Positive values are in favor of the Nordic group. A 12-week Nordic hamstring exercise intervention did not affect the level of muscle activity and relative contribution of hamstring muscles in the late-swing phase of high-speed running. Because of the low amount of data sets, results should be interpreted cautiously.

Determining Maximal Outcome Improvement Thresholds for Patient-Reported Outcome Measures After Primary ACL Reconstruction: A Mid-Term Follow-up Study Using the Anchor Method.

The clinical interpretation of patient-reported outcome measures (PROMs) after anterior cruciate ligament (ACL) reconstruction (ACLR) can be challenging. This study aimed to establish the clinical relevance of PROMs by determining maximal outcome improvement (MOI) thresholds at mid-term follow-up after primary ACLR. A total of 343 patients who underwent primary single-bundle ACLR using hamstring tendon autograft at our institute were included. Patients were queried with a 2-option anchor question regarding satisfaction with their current knee symptom state. The MOI of a PROM was calculated for each patient as the percentage of improvement normalized by the maximal possible improvement. The MOI threshold for each PROM was determined as the optimal cutoff value for predicting patient satisfaction based on receiver operating characteristic curve analysis. Multivariable logistic regression analyses were performed to identify predictors of achieving these thresholds. Subgroup analyses that stratified the time from injury to surgery within the cohort were performed, and MOI thresholds were recalculated within each of these subgroups. The PROMs evaluated in this study were the modified Lysholm Knee Score and the International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC) score. The calculated MOI threshold was 35.1% for the Lysholm score and 46.7% for the IKDC score. A longer time from injury to surgery reduced the odds of achieving the MOI threshold for the Lysholm score (odds ratio [OR] per time bracket = 0.7114, p < 0.0001) and IKDC score (OR = 0.8038, p = 0.0003). Male sex was associated with higher odds of achieving the MOI threshold for the IKDC score (OR = 1.9645, p = 0.0143). For patients with chronicity of ≤6 months, the MOI threshold was 35.1% for the Lysholm score and 57.9% for the IKDC score, and for patients with chronicity of >6 months, the thresholds were 24.5% and 27.1%, respectively. The calculated MOI thresholds for the Lysholm and IKDC scores at mid-term follow-up after primary ACLR were 35.1% and 46.7%, respectively. Greater chronicity of the ACL injury was associated with lower odds of achieving the MOI thresholds for the PROMs at mid-term follow-up. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

How statistically fragile are randomized controlled trials comparing quadriceps tendon autografts with hamstring or bone-patellar tendon-bone autografts in anterior cruciate ligament reconstruction?

To determine the statistical fragility of randomized controlled trials (RCTs) which compare the use of quadriceps tendon (QT) autografts to either hamstring tendon (HT) or bone-patellar tendon-bone (BPTB) autografts in anterior cruciate ligament reconstruction (ACLR). A search was conducted across PubMed, MEDLINE and EMBASE databases for RCTs comparing QT autografts to HT or BPTB autografts in ACLR from inception to 21 April 2024. Studies that reported ≥1 statistically significant continuous outcome, statistically significant dichotomous outcome and/or nonsignificant dichotomous outcome were included for analysis. The fragility index (FI), continuous fragility index (CFI) and reverse fragility index (RFI) were calculated for significant dichotomous outcomes, significant continuous outcomes and nonsignificant dichotomous outcomes, respectively. A total of 11 RCTs comprising 716 patients were included. The mean sample size was 65.8 patients. The median FI among nine outcomes from four studies was 1.0 (interquartile range [IQR], 0.5; 95% confidence interval [CI], 0.6-1.4; range 0.5-1.5). The number of patients lost to follow-up at the final follow-up period was more than the study-specific FI in three (75%) studies. The median CFI among 30 outcomes from six studies was 4.9 (IQR, 10.1, 95% CI, 3.9-8.2; range 0-18.2). The number of patients lost to follow-up at the final follow-up period was more than the study-specific CFI in four (66.7%) studies. The median RFI among 10 outcomes from five studies was 5.0 (IQR, 3.5; 95% CI, 3.4-6.6; range 1.0-9.0). The number of patients lost to follow-up at the final follow-up period was more than the study-specific RFI in four (80%) studies. This systematic review revealed that regardless of the metric used, RCTs comparing QT autografts to HT or BPTB autograft options in ACLR are statistically fragile. While the indices of statistical fragility evaluated in this study are important metrics of robustness to consider, their application in research and clinical practice needs to be further elucidated. Level I.

Early versus delayed start of weight-bearing after arthroscopic anterior cruciate ligament reconstruction with hamstring tendons.

The aim of this prospective randomized clinical study was to compare the clinical and second-look arthroscopic outcomes of early weight-bearing and delayed weight-bearing rehabilitation protocols following anterior cruciate ligament (ACL) reconstruction with hamstring tendons. This prospective study involved 90 patients who underwent ACL reconstruction with hamstring tendons. The patients were randomly assigned to either perform weight-bearing exercises at three weeks postoperatively (group A) or at one week postoperatively (group B). Evaluation of the patients was conducted at 3, 6, and 12 months postoperatively, focusing on knee range of motion, thigh circumference, and knee function assessed using the International Knee Documentation Committee (IKDC) form and Lysholm knee score. Graft evaluation was performed based on tension, tear, and synovial coverage via second-look arthroscopy at least one year after reconstruction. Group B exhibited significantly greater knee extension and flexion angles at 3 and 6 months compared to group A. IKDC and Lysholm scores were significantly higher in group B at 3 and 6 months. Additionally, the difference in thigh circumference between groups A and B was smaller at all evaluation periods, indicating less muscle atrophy in group B. Furthermore, there was no significant difference in synovial coverage, graft tear, or tension between the two groups based on second-look arthroscopy findings. This study demonstrates that an early weight-bearing protocol leads to faster recovery of knee joint function and muscle strength, facilitating a quicker return to sports activities. Additionally, there was no significant difference in graft morphology observed at second-look arthroscopy between the two groups at one year postoperative. Therefore, clinicians are encouraged to develop suitable early weight-bearing rehabilitation protocols for patients who have undergone ACL surgery.

Randomized Controlled Study Comparing Hamstring Graft and Peroneus Longus Tendon Graft in Arthroscopic ACL Reconstruction.

Graft choice for anterior cruciate ligament reconstruction (ACLR) has been evolving. The peroneus longus tendon (PLT) has been seen as a suitable choice for ACLR, providing comparable results to those of hamstring tendon (HT) autograft, but its clinical relevance in terms of return to sports, to our knowledge, has not been studied. One hundred and twenty patients who sustained an isolated ACL injury were enrolled and underwent ACLR using tripled or quadrupled PLT autograft (if graft thickness exceeded 10 mm then tripled) or quadrupled HT autograft. Patients were followed for 24 months. Functional scores (International Knee Documentation Committee [IKDC] and Tegner-Lysholm scores) were assessed preoperatively and at 3, 6, 12, and 24-month post-operatively. Graft diameter and graft harvesting time were measured intraoperatively. Donor-site morbidity was evaluated using subjective evaluation. Time to return to sports in both groups was compared. The mean diameter of the PLT autograft was significantly larger than that of the HT autograft, and the mean graft harvesting time was less (P < 0.001). Patients in the PLT group returned to sports a mean of 36 days earlier than those in the HT group (P < 0.001) and had a lower rate of donor-site morbidity, and better patient-reported outcomes at the knee (P < 0.001). There was a significant difference between the groups in IKDC and Tegner-Lysholm scores at the 24-month follow-up. Despite some donor site complications, such as numbness and infection, both PLT and HT grafts offer acceptable knee stability. However, PLT grafts seem to provide superior subjective functional outcomes based on patient-reported scores. More research is needed to further establish these findings and optimize graft choices for individual patients.

A new field-test for assessing the medial and lateral hamstring strength at long-muscle length

This research investigates the influence of tibial rotations with knee flexion (KF) on the electromyographic (EMG) activities of hamstring muscles (HM) groups and the strength ratio between the medial and lateral rotation of the tibia. A cross-sectional design was employed to assess muscle activity, isometric strength and reliability. The research was conducted in a controlled laboratory environment. Thirty-six amateur male athletes were recruited as volunteers. The measures included peak muscle activity of the semitendinosus and biceps femoris long head, the knee flexors’ isometric strength ratio and reliability. The isometric strength ratios of medial (MR) to lateral (LR) tibial rotations were 0.94 ± 0.17 at 90°, and 0.93 ± 0.10 at both 60° and 30° of KF angulation. Tibial position significantly influenced knee flexion strength as well as HM activity, irrespective of KF angulation. Specifically, biceps femoris activity increased by 33.6% in LR compared to MR, while semitendinosus activity increased by 22.6% in MR compared to LR. The Knee-Rotation test (KR-test) can be a valuable tool for evaluating both HM groups (ICC > 0.87), and identifying the primary target for strengthening purposes during the injury prevention process. It provides insights for effective rehabilitation and training interventions.

Posterior Cruciate Ligament Reconstruction Improves Sexual Health Post-Operatively

PurposeThe purpose of this study was to investigate changes in sexual function and quality of life following arthroscopic posterior cruciate ligament (PCL) reconstruction. MethodsPatients aged between 18 and 45 years who underwent PCL reconstruction were considered for inclusion. At the time of hospital admission, each patient was asked to complete the New Sexual Satisfaction Scale-Short Form (NSSS-S), before injury (preinjury) and at the time of hospital admission (preoperative). In addition, patients were followed for a minimum of 24 months (final follow-up). Quality of life was measured using the Anterior Cruciate Ligament Quality of Life Questionnaire (ACL-QOL) at hospital admission (preoperative) and at the 24-month follow-up visit (final follow-up). ResultsA total of 35 patients were included in the study; 24 (68.6%) were male, and 11 were female (31.4%). The mean age at the time of surgery was 29.23 ±7.52 years, and the mean follow-up duration was 52.97 ±22.69 months. In all patients, the hamstring tendon was used. Sexual activity at the last follow-up visit was significantly different from that preoperatively (p=0.024), while no difference was observed between the preinjury and last follow-up values (p=0.243). Sexual activity was more frequent before injury than preoperatively (p=0.009). Quality of life at the last follow-up visit was significantly better than that preoperatively (p<0.001). ConclusionsReconstructive surgery after PCL injury improves the sexual health of patients regardless of age or sex.

Sex-based differences in hamstrings stiffness assessment in football players using ultrasound shear wave elastography.

Hamstring stiffness varies among individuals and can influence athletic performance and injury risk. Sex-based differences in hamstring stiffness among football players have not been thoroughly investigated. This study aimed to assess these differences using shear wave elastography (SWE), a non-invasive ultrasound technique that quantifies tissue stiffness. The study recruited 30 football players (15 male, 15 female) in June 2022 during their annual medical check-up. Participants were aged 18-40 years, engaged in regular training, and had no history of lower limb musculoskeletal injury in the six weeks preceding the study. SWE was used to measure shear wave velocity (SWV) in the hamstring muscles: semitendinosus (ST), semimembranosus (SM), and biceps femoris (BF). Independent t-tests were used to compare the SWV values of the hamstring muscles between sexes and between dominant and non-dominant legs. ST muscle had a statistically significant difference in SWV based on gender and leg dominance with marked differences particularly in the non-dominant leg across both genders (P=0.02; Bonferroni corrected P=0.05). SWV for ST in male group was significantly higher than that in female group; the mean elasticity of the male group for dominant and non-dominant leg were 3.8±1.5 and 4.1±1.2 m/s, respectively; and the mean elasticity of the female group for dominant and non-dominant leg were 2.9±0.7 and 2.8±0.7 m/s respectively. In contrast, SWV differences in the SM and BF muscles were not statistically significant(P=0.187 and 0.760, respectively). The study revealed significant sex-based differences in hamstring stiffness among football players, as assessed by SWE. ST muscle stiffness was associated with higher SWV in male group and show stronger correlation with non-dominance leg. These findings can contribute to individualized training programs and injury prevention strategies.

Evaluating the Importance of Return to Sports and Hamstring Strength in a Discrete Choice Experiment for Anterior Cruciate Ligament Injury.

With emerging treatments for anterior cruciate ligament (ACL) injury, analysis of patient preferences is lacking to align clinical care and research with patient priorities. To identify patient priorities for outcomes after surgical intervention if they were to sustain an ACL tear, analyze what outcome measures influenced preferences, and determine whether patient demographics influenced preferences. Cross-sectional study. The authors screened patients aged 18 to 30 years who presented for upper extremity complaints to a single institution in 2023. Patients were excluded for current lower extremity injury or history of a knee injury requiring surgical consultation. The authors designed a discrete choice experiment through literature review of outcome measures for bridge-enhanced ACL restoration (BEAR) and ACL reconstruction (ACLR) with hamstring tendon autograft. Measures included return to sports, risk of arthritis, risk of reinjury, and hamstring strength. Patients chose surgery A (ACLR with hamstring tendon autograft) or surgery B (BEAR) and then rated the importance of each outcome measure on their selection. In total, 100 participants (36 female; mean age, 25.1 ± 4.0 years) completed the discrete choice experiment. Overall, 56.0% participated in sports and 80.0% were employed. Based on surgery choice group, there were no significant differences in sex, age, Marx Activity Scale score, sports participation, or employment status between patients who selected BEAR or ACLR with hamstring tendon autograft (all P > .361). Return to sports and hamstring strength were significant priorities for patients in procedure selection (P ≤ .011). Of the patients who selected ACLR with hamstring tendon autograft, 31.6% would not elect to undergo this procedure. In this discrete choice experiment of adults without prior ACL injury, return to sports and hamstring strength were identified as patient priorities when selecting a procedure for ACL injury. Risk of reinjury, however, was not a significant factor in procedure selection. Importantly, these priorities were maintained regardless of patient characteristics, activity level, or employment status.

Comparison of Medial Hamstring Length Between Harvesting Methods Using Anterior and Posterior Approaches.

Medial hamstring tendons harvesting can be performed through either an anterior or a posterior approach. It has been suggested that using a posterior approach may result in a longer length of harvestable tendon compared with an anterior approach. There would be no difference in the length of the harvestable tendon between the anterior and posterior approaches. Case-control study; Level of evidence, 3. A retrospective study was conducted at the primary institution using prospectively collected data from skeletally mature Chinese patients who underwent medial hamstring tendons harvesting between January 2008 and December 2021. Patients were excluded if they had experienced graft harvesting complication or if only 1 medial hamstring tendon was harvested. One-to-one exact matching was performed between the 2 approaches based on body height and sex. The outcome assessed was the length of the harvested tendon. A total of 536 patients underwent medial hamstring tendons harvesting using an anterior approach, while 58 underwent it using a posterior approach, all of whom met the inclusion criteria. A group of 54 matched pairs were identified. The length of the harvested semitendinosus tendon was 263 ± 29 mm in the anterior approach and 256 ± 28 mm in the posterior approach (P = .09; Student t test). The mean difference in the length of the harvested semitendinosus tendon between the 2 approaches was 7 mm. The length of the gracilis tendon was 226 ± 29 mm and 223 ± 29 mm in the anterior approach and the posterior approach, respectively (P = .30; Student t test). In a retrospective 1:1 case-control study with exact matching of body height and sex, it was found that there was no difference in the length of the semitendinosus tendon and the gracilis tendon harvested using a posterior approach compared with an anterior approach. The mean difference between the 2 approaches was 7 mm for the semitendinosus tendon and 3 mm for the gracilis tendon, respectively.

Evaluation of Lateral and Medial Parts of the Hamstring Muscle Fatigue Symmetry in Professional Footballers Cleared to Play After ACL Reconstruction.

Objectives: Rupture of the anterior cruciate ligament (ACL) is a severe injury common in sports. It also has a high rate of re-injury. The aim of this work was to assess hamstring muscle fatigue in active football players after ACL reconstruction who were cleared to play and to determine symmetry between the lateral and medial hamstring muscles. Methods: In professional football players post ACL reconstruction (n = 25) and non-injured players (n = 26), the bioelectrical activity of the medial (biceps femoris-BF) and lateral (semimembranosus and semitendinosus-SEM) hamstring muscles was measured during 60 s of isometric contraction. The fatigue variables were calculated using the Continuous Wavelet Transform (CWT) tool. Results: The football players following ACL reconstruction demonstrated significant asymmetry in fatigue of the lateral and medial hamstring muscles, with greater fatigue in the SEM compared to the BF muscle. Moreover, in those after reconstruction, the changes are more pronounced, with higher muscle fatigue in both limbs (they have lower MDF than non-injured players) and more severe SEM muscle insufficiency (noted in both limbs but with greater intensity in the non-operated one). Conclusions: The higher SEM muscle fatigue observed in this study influenced the lateral-to-medial activation ratio within the hamstring muscle, which may be a probable cause of this muscle's insufficiency in laterally stabilizing the knee in the frontal and transverse plane. Furthermore, the hamstring muscles after reconstruction were more fatigued in both limbs, which may be another risk factor for ACL graft rupture. Therefore, increased fatigue in specific hamstring muscles may indicate the direction in which knee stabilization is compromised due to ACL overload. A muscle that becomes fatigued and inefficient more quickly also becomes ineffective in performing its function sooner, which can lead to increased overloading forces acting on the ACL graft.

The Additional Effect of Neurodynamic Slump and Suboccipital Muscle Inhibition to Passive Stretching of the Short Hamstring: A Single-Blind, Randomized Controlled Trial.

Hamstring shortening is a significant musculoskeletal condition affecting the posture and mobility of the spine and lower extremities. This study examined the impact of incorporating neurodynamic slump stretch and suboccipital muscle inhibition into passive static stretching on hamstring flexibility in individuals with short hamstrings. 117 female participants were classified into three groups: the control group, which received passive static stretch of the hamstring muscle; the neurodynamic slump group, which received neurodynamic slump stretch with passive static stretch; and the suboccipital muscle inhibition group, which received suboccipital muscle inhibition with passive static stretch, for three sessions a week, 10 min each, for four weeks. The outcome measures were the popliteal angle test (PAT), straight leg raising (SLR) test, and forward bending test (FBT) at baseline, immediately following the first session and after four weeks. Statistically significant differences were found within groups (p < 0.001) for all outcome measures. Between the groups, there was a more significant improvement in the PAT and the SLR tests, favoring the neurodynamic slump and suboccipital muscle inhibition groups in comparison with the passive static stretch group (p < 0.001) with no significant difference between the two groups after the first session and at four weeks of treatment. However, the FBT showed no significant differences immediately following the first session or at four weeks of treatment (p > 0.05). This study found that incorporating neurodynamic slump stretch and suboccipital muscle inhibition into passive static stretch techniques effectively treats short hamstrings in healthy individuals.

Functional Assessment of Anterior Cruciate Ligament Reconstruction Using Peroneus Longus vs. Hamstring Tendon at 6, 12, And 24 Months Follow Up: A Meta-Analysis

Background: Anterior cruciate ligament (ACL) tear occurs between 29 to 38 cases per 100.000 people annually with more than half of cases requiring an ACL reconstruction. Peroneus longus tendon (PLT) has growing popularity as an autograft for ACL reconstruction providing comparable outcomes with proper graft diameter size, lack of donor site morbidity and uncomplicated harvesting technique. Unfortunately, certain studies did not agree with the superiority of PLT to the standard hamstring tendon (HT). Objective: The aim of study is to compare the knee functional outcome of an ACL reconstruction using peroneus longus and hamstring tendon according to recent publications. Methods: This study conducted a thorough systematic search for relevant scientific reports on multiple medical databases, including PubMed, Embase, and Google Scholar, using a combination of keywords such as "peroneus longus," “hamstring tendon,” "ACL reconstruction," “IKDC,” and “Lysholm”. The search was performed in April 2013-2023, resulting in 1567 studies. Two reviewers (RR, WA) independently screened the abstracts and reference lists, with any discrepancies resolved through consensus, concluding 5 included studies. Results: Five studies are included with a total of 538 patients consisting of 267 patients who underwent ACL reconstruction with PLT and 271 patients who underwent ACL reconstruction with HT. Up to 24 months follow-up, there are equally balanced satisfactory functional outcomes between ACL reconstruction using peroneus longus and hamstring tendon, in terms of IKDC (I2 = 74%; SMD = 0.08 95%CI, -0.21 to 0.38; p = 0.57) and Lysholm score (I2 = 75%; SMD = 0.06 95%CI, -0.27 to 0.39; p = 0.73). Conclusion: ACL reconstruction using the peroneus longus tendon is a safe and effective procedure with excellent short to long term functional outcome of the knee. Keywords: Anterior Cruciate Ligament Reconstruction, Functional Outcome, Hamstring tendon, Human, Peroneus Longus Tendon Keywords: Anterior Cruciate Ligament Reconstruction, Functional Outcome, Hamstring tendon, Human, Peroneus Longus Tendon.

Anthropometric predictors of hamstring graft size in anterior cruciate ligament reconstruction

Background: The anterior cruciate ligament (ACL) is commonly injured in the knee joint, necessitating surgical reconstruction where quadrupled hamstring tendon autografts are frequently utilized for their favourable outcomes. Predicting the appropriate dimensions of these grafts is essential for surgical success. This study aims to investigate whether simple anthropometric measurements-height, weight, body mass index (BMI), thigh length, and circumference-can predict the length and diameter of quadrupled hamstring tendons used in ACL reconstruction. Methods: This cross-sectional study included 45 patients undergoing ACL reconstruction with quadrupled hamstring autografts at department of orthopaedics, Renai Medicity Kerala, India. Preoperative anthropometric measurements were correlated with intraop graft dimensions using Pearson correlation and SPSS statistical software (version 22). Results: Taller patients exhibited a positive correlation with graft diameter (p=0.028). Height and thigh length correlated positively with both gracilis and semitendinosus tendon lengths (p&lt;0.001). Thigh circumference correlated positively with semitendinosus length (p=0.005), while weight, BMI, and other measures did not significantly correlate with graft dimensions. Conclusions: Anthropometric measurements, particularly height and thigh length, serve as valuable predictors for hamstring graft dimensions in ACL reconstruction. These findings may assist surgeons in selecting appropriate grafts and optimizing surgical outcomes.

Physiologic Preoperative Knee Hyperextension Is Not Associated With Postoperative Laxity, Subjective Knee Function, or Revision Surgery After ACL Reconstruction With Hamstring Tendon Autografts.

There is concern that physiologic knee hyperextension may be associated with inferior outcomes after anterior cruciate ligament reconstruction (ACLR) using hamstring tendon (HT) autografts. To assess whether there is an association between contralateral passive preoperative knee hyperextension (≤-5°) and postoperative anterior knee laxity, subjective knee function, or revision surgery after ACLR using HT autografts. Cohort study; Level of evidence, 3. Patients without concomitant ligament injuries who underwent primary ACLR using an HT autograft at Capio Artro Clinic, Stockholm, Sweden, between January 1, 2005, and December 31, 2018, were identified. The cohort was dichotomized into the hyperextension group (≤-5°) and the no hyperextension group (>-5°) depending on preoperative contralateral passive knee extension degree. Anterior knee laxity (KT-1000 arthrometer; 134 N) was assessed preoperatively and at 6 months postoperatively. The Knee injury and Osteoarthritis Outcome Score (KOOS) was collected preoperatively and at 1, 2, and 5 years postoperatively. Patients who underwent revision ACLR at any institution in Sweden within 5 years of the primary surgery were identified in the Swedish National Knee Ligament Registry. A total of 6104 patients (53.5% male) for whom knee range of motion measurements were available were identified (hyperextension group [≤-5°]: 2350 [38.5%]; mean extension, -6.1°± 2.3° [range, -20° to -5°]; no hyperextension group [>-5°]: 3754 [61.5%]; mean extension, 0°± 1.4° [range, -4° to 15°]). There were no intergroup differences in anterior knee laxity preoperatively (hyperextension group, 3.6 ± 2.8 mm; no hyperextension group, 3.7 ± 2.7 mm; P = .24) or postoperatively (hyperextension group, 1.8 ± 2.3 mm; no hyperextension group, 1.8 ± 2.2 mm; P = .41). The only significant but nonclinically relevant intergroup differences were seen in the KOOS Symptoms subscale at the 1-year follow-up (hyperextension group, 81.4 ± 16.0; no hyperextension group, 80.3 ± 16.5; P = .03) and in the Sport and Recreation subscale at the 5-year follow-up (hyperextension group, 73.0 ± 25.6; no hyperextension group, 75.7 ± 24.3; P = .02). No other significant intergroup differences were noted preoperatively or at 1, 2, or 5 years postoperatively in any of the KOOS subscales. The overall revision ACLR rate at ≤5 years after the primary surgery was 4.9% (302 of 6104 patients). The hazard for revision ACLR in the no hyperextension group (4.5%; 170 of 3754 patients) was not significantly different from that in the hyperextension group (5.6%; 132 of 2350 patients) (hazard ratio, 0.89; 95% CI, 0.71 to -1.12; P = .34). A subsequent subanalysis showed that the hazard of revision ACLR in patients with no hyperextension was not significantly different from that of patients with ≤-10° of extension (5.8%; 27 of 467 patients) (hazard ratio, 0.91; 95% CI, 0.61 to 1.36; P = .65). Preoperative passive contralateral knee hyperextension (≤-5°) was not associated with postoperative anterior knee laxity, subjective knee function, or revision surgery ≤5 years after ACLR using HT autografts. Therefore, the presence of knee hyperextension alone should not be considered a contraindication per se for the use of HT autografts in ACLR.