for 4.0% to 17.6% of all injuries in this population. 2 , 3 The number of hamstring strains has doubled in the 4 seasons from 2012 to 2015 when compared with the previous 4 seasons. 6 Hamstring injuries also lead to a significant time loss from Gaelic football, with 38.5 days absent per 1000 hours
Siobhán O’Connor, Noel McCaffrey, Enda F. Whyte, Michael Fop, Brendan Murphy and Kieran A. Moran
Kevin M. Cross, Kelly K. Gurka, Susan Saliba, Mark Conaway and Jay Hertel
college-age and professional soccer, hamstring strains alone account for as many as 16% of all reported injuries. 8 , 16 – 18 As college-age and professional soccer athletes are more likely to strain their hamstring, most analysis of thigh muscle strains has been specific to the hamstrings. Among college
Jennifer W. Cuchna, Lauren Welsch, Taylor Meier, Chyrsten L. Regelski and Bonnie Van Lunen
Are Nordic hamstring exercises more effective than standardized training in reducing hamstring strain injury rates in competitive soccer players over the course of at least one season?
Clinical Bottom Line:
The evidence supports the use of Nordic hamstring exercises to reduce hamstring injury incidence rates over a competitive soccer season. Therefore, progressive Nordic hamstring exercises should be included within some aspect of a practice to prevent the occurrence of hamstring injuries.
Siobhán O’Connor, Róisín Leahy, Enda Whyte, Paul O’Donovan and Lauren Fortington
Camogie is one of Ireland’s most popular sports, and the full contact nature presents a high potential for injury. This study aims to present the first overview of elite and nonelite camogie injuries by examining adult players’ self-reported worst injuries from one season. At least one injury was sustained by 88.2% of camogie players during the previous season and 60.0% sustained 2+ injuries. Knee and ankle ligaments, hamstring strains and hand/fingers/thumb fractures were key injuries identified, which can lead to substantive health and economic impacts. Further research to establish the mechanism of these injuries is required in order to start shaping potential measures for their prevention.
Simone Ciacci, Rocco Di Michele, Silvia Fantozzi and Franco Merni
Kinematic asymmetry is believed to be associated with elevated risk for muscle injury, but little is known about the links between hamstring injuries and asymmetry of sprinting mechanics.
To evaluate the value of kinematic analysis of sprinting for the detection of injury-related asymmetry in athletes with a history of hamstring strain.
Six sub-elite male sprinters, including two who sustained a hamstring strain injury.
Absolute differences between left and right symmetry indices and symmetry angles were both calculated for ground contact time and selected angular displacements. Measurements were acquired at foot strike, during the stance phase, and at toe-off.
At toe-off, injured athletes exhibited greater knee flexion and less hip extension for the injured extremity compared to the uninjured extremity. Symmetry indices for these variables markedly exceeded an established 15% threshold for clinically relevant asymmetry. Each of the uninjured athletes exhibited a high degree of symmetry for all parameters, with mean values for symmetry indices significantly lower than the 15% threshold (P < 0.05).
Kinematic analysis of sprinting asymmetry appears to be valuable for identification of elevated risk for hamstring injury.
Sports medicine assessment and treatment techniques are ever developing and becoming more holistic. Traditional musculoskeletal assessment is changing to incorporate neural tissue pathology. Neural tension tests assess the mobility of neural tissue in the extremities and spinal canal. Positive adverse neural tension tests suggest poor mobility of neural tissue. Athletes with adverse neural tension often present with pain and decreased range of motion. These disorders can occur individually or can be associated with sports injuries. Ankle sprains, hamstring strains, tennis elbow, and thoracic outlet syndrome are some conditions that respond well to treatment of adverse neural tension. Reports of improved treatment outcomes following neural tension assessment and treatment suggest that adverse neural tension should be considered as a possible source of pain and dysfunction. This paper outlines concepts necessary to understand adverse neural tension including neuroanatomy, pathology, assessment techniques, and common sports injuries that may have an adverse neural tension component.
Paul Comfort, Amy Regan, Lee Herrington, Chris Thomas, John McMahon and Paul Jones
Regular performance (~2×/wk) of Nordic curls has been shown to increase hamstring strength and reduce the risk of hamstring strain injury, although no consensus on ankle position has been provided.
To compare the effects of performing Nordic curls, with the ankle in a dorsiflexed (DF) or plantar-flexed (PF) position, on muscle activity of the biceps femoris (BF) and medial gastrocnemius (MG).
15 male college athletes (age 22.6 ± 2.1 y, height 1.78 ± 0.06 m, body mass 88.75 ± 8.95 kg).
A repeated-measures design was used, with participants performing 2 sets of 3 repetitions of both variations of Nordic curls, while muscle activity was assessed via surface electromyography (EMG) of the BF and MG. Comparisons of muscle activity were made by examining the normalized EMG data as the percentage of their maximum voluntary isometric contraction.
Paired-samples t test revealed no significant difference in normalized muscle activity of the BF (124.5% ± 6.2% vs 128.1 ± 5.0%, P > .05, Cohen d = 0.64, power = .996) or MG (82.1% ± 3.9% vs 83.5 ± 4.8%, P > .05, Cohen d = 0.32, power = .947) during the Nordic curls in a PF or DF position, respectively.
Ankle position does not influence muscle activity during the Nordic curl; however, performance of Nordic curls with the ankle in a DF position may be preferential, as this replicates the ankle position during terminal leg swing during running, which tends to be the point at which hamstring strains have been reported.
Paul W.M. Marshall, Ric Lovell and Jason C. Siegler
Passive muscle tension is increased after damaging eccentric exercise. Hamstring-strain injury is associated with damaging eccentric muscle actions, but no research has examined changes in hamstring passive muscle tension throughout a simulated sport activity. The authors measured hamstring passive tension throughout a 90-min simulated soccer match (SAFT90), including the warm-up period and every 15 min throughout the 90-min simulation.
Passive hamstring tension of 15 amateur male soccer players was measured using the instrumented straight-leg-raise test. Absolute torque (Nm) and slope (Nm/°) of the recorded torque-angular position curve were used for data analysis, in addition to total leg range of motion (ROM). Players performed a 15-min prematch warm-up, then performed the SAFT90 including a 15-min halftime rest period.
Reductions in passive stiffness of 20–50° of passive hip flexion of 22.1−29.2% (P < .05) were observed after the warm-up period. During the SAFT90, passive tension increased in the latter 20% of the range of motion of 10.1−10.9% (P < .05) concomitant to a 4.5% increase in total hamstring ROM (P = .0009).
The findings of this study imply that hamstring passive tension is reduced after an active warm-up that includes dynamic stretching but does not increase in a pattern suggestive of eccentric induced muscle damage during soccer-specific intermittent exercise. Hamstring ROM and passive tension increases are best explained by improved stretch tolerance.
Derek N. Pamukoff, Sarah E. Bell, Eric D. Ryan and J. Troy Blackburn
Hamstring musculotendinous stiffness (MTS) is associated with lower-extremity injury risk (ie, hamstring strain, anterior cruciate ligament injury) and is commonly assessed using the damped oscillatory technique. However, despite a preponderance of studies that measure MTS reliably in laboratory settings, there are no valid clinical measurement tools. A valid clinical measurement technique is needed to assess MTS and permit identification of individuals at heightened risk of injury and track rehabilitation progress.
To determine the validity and reliability of the Myotonometer for measuring active hamstring MTS.
Descriptive laboratory study.
33 healthy participants (15 men, age 21.33 ± 2.94 y, height 172.03 ± 16.36 cm, mass 74.21 ± 16.36 kg).
Main Outcome Measures:
Hamstring MTS was assessed using the damped oscillatory technique and the Myotonometer. Intraclass correlations were used to determine the intrasession, intersession, and interrater reliability of the Myotonometer. Criterion validity was assessed via Pearson product–moment correlation between MTS measures obtained from the Myotonometer and from the damped oscillatory technique.
The Myotonometer demonstrated good intrasession (ICC3,1 = .807) and interrater reliability (ICC2,k = .830) and moderate intersession reliability (ICC2,k = .693). However, it did not provide a valid measurement of MTS compared with the damped oscillatory technique (r = .346, P = .061).
The Myotonometer does not provide a valid measure of active hamstring MTS. Although the Myotonometer does not measure active MTS, it possesses good reliability and portability and could be used clinically to measure tissue compliance, muscle tone, or spasticity associated with multiple musculoskeletal disorders. Future research should focus on portable and clinically applicable tools to measure active hamstring MTS in efforts to prevent and monitor injuries.
Whitney Williams and Noelle M. Selkow
Context: Decreased hamstring flexibility can lead to a plethora of musculoskeletal injuries, including low back pain, hamstring strains, and patellofemoral pain. Lack of flexibility may be the result of myofascial adhesions. The fascia connected to the hamstrings is part of the superficial back line that runs from the cranium to the plantar aspect of the foot. Any disruption along this chain may limit the flexibility of the hamstring. Objective: To investigate if self-myofascial release (SMR) of the plantar surface of the foot in addition to the hamstring group was more effective at improving the flexibility of the hamstrings when compared with either intervention alone. Design: Cross-over study. Setting: Athletic training facility. Participants: Fifteen college students (5 males and 10 females; age: 20.9 [1.4] y, height: 173.1 [10.3] cm, mass: 80.0 [24.9] kg) who were not older than 30, with no history of low back pain or injury within the past 6 months, no history of leg pain or injury within the past 6 months, no current signs or symptoms of cervical or lumbar radicular pain, no current complaint of numbness or tingling in the lower-extremity, and no history of surgery in the lower-extremity or legs. Interventions: Each participant received each intervention separated by at least 96 hours in a randomized order: hamstring foam rolling, lacrosse ball on the plantar surface of the foot, and a combination of both. Main Outcome Measures: The sit-and-reach test evaluated hamstring flexibility of each participant before and immediately after each intervention. Results: There were no significant differences found among the SMR techniques on sit-and-reach distance (F
2,41 = 2.7, P = .08,