Recurrent Hamstring Strain Research Articles

Biomechanical Parameters Assessed During Running Among Running-Related Athletes with Recurrent Hamstring Strain Injury: A Scoping Review

Biomechanical Parameters Assessed During Running Among Running-Related Athletes with Recurrent Hamstring Strain Injury: A Scoping Review

Previous hamstring muscle strain injury alters passive tissue stiffness and vibration sense

BackgroundHamstring strain is one of the most common among sports injuries. A previous history of this injury is considered a strong predictor of recurrent hamstring strain injury. It has been suggested that fascial tissue alters after muscle strain injury. However, the association between previous hamstring strain injury and tissue stiffness and vibration sense detection has not been investigated. ObjectivesWe aimed to determine whether a previous history of hamstring strain injury affects tissue stiffness and vibration sense in professional soccer players. MethodThe stiffness (MyotonPRO®) and vibration disappearance threshold (tuning fork) were measured in eight professional soccer players with previous history of hamstring strain and eight uninjured players. The differences between two groups’ means were analyzed. Side-to-side differences between injured and uninjured legs were also analyzed. Results: The tissue stiffness was higher, and the vibration disappearance threshold was lower, in previously injured players when compared to uninjured players. Similar differences were found between injured and uninjured legs. No significant relationship was detected between the age or body mass index (BMI) for both tissue stiffness and vibration disappearance threshold (all P < 0.05). ConclusionsSoccer players with a previous history of hamstring strain injury exhibited higher tissue stiffness and lower vibration sensitivity in the injured leg, regardless of the age and BMI. The results that players who have a previous hamstring strain injury with altered tissue stiffness and vibration sense will be useful and feasible evaluation for chronic muscle strain condition.

Hamstring strains in professional rugby players result in increased fascial stiffness without muscle quality changes as assessed using shear wave elastography

IntroductionHamstring strain injury is common among sports injuries. A previous history of this injury is considered a strong predictor of recurrent hamstring strain injury. Fascial tissue reportedly becomes stiffer after hamstring strain injury. However, the association between fascial stiffness and previous hamstring strain injury has not been investigated in clinical studies. We aimed to determine whether a previous history of hamstring strain injury affects fascial tissue and muscle tissues using shear wave elastography. MethodIn eleven male professional rugby players, the stiffness as a shear modulus (kPa) of fascial tissue and muscle was measured on the specific injured area measured by magnetic resonance imaging (MRI) at resting position by using shear wave elastography. The side-to-side differences between the injured and the uninjured side were analyzed. The length and area of the muscle scar tissue were evaluated by MRI in relation to fascial stiffness. ResultsThe shear elastic modulus of fascia was stiffer in the injured vs. the uninjured side; however, no difference was observed in the muscle. No significant relationship was detected between the length and area of the muscle scar tissue (all P > 0.05). DiscussionRugby players with a previous history of hamstring strain injury exhibited passive stiffness of fascial tissues in the injured leg, regardless of the length or area of the muscle scar tissue. However, the passive stiffness of muscles was same between the injured and the uninjured leg. ConclusionThe results can be beneficial to consider future risk for hamstring strain injuries.

Preventing the seemingly unpreventable – challenging the return-to-play criteria for recurrent hamstring strain prevention

&#x0D; Background: Hamstring strains are one of the most common injuries in sport. Previous injury has been found to be one of the greatest risk factors associated with recurrent hamstring strains. Although rehabilitation programmes have been developed and implemented to aid safe and efficient return-to-play, the incidence of hamstring injuries has not decreased. &#x0D; Discussion: As hamstring strains most commonly occur during the eccentric phase of muscle action, rehabilitation should focus on eccentric muscle strengthening. The L-protocol and the Nordic Hamstring Exercise protocol strengthen the hamstring muscles eccentrically. They have been found to be effective in decreasing the incidence of new hamstring strains as well as the rate of recurrence. This commentary therefore aims to suggest changes to the return-to-play criteria following hamstring strains to prevent the seemingly unpreventable.

Hamstring Injury Prevention Practices in Elite Sport: Evidence for Eccentric Strength vs. Lumbo-Pelvic Training.

Hamstring strain injuries are endemic in running-based sports. Given the economic and performance implications of these injuries, a significant body of research has emerged in recent years in an attempt to identify risk factors and develop or optimise injury prevention strategies. Surveys of injury prevention practices among medical and conditioning staff in elite sport suggest that many sporting clubs invest significant efforts in eccentric hamstring conditioning and lumbo-pelvic or trunk stability programmes. The purpose of this narrative review was to critically evaluate the evidence underpinning these practices. Single-exercise eccentric training interventions have proven effective in the prevention of primary and recurrent hamstring strains, when compliance is adequate. However, despite its almost universal acceptance, the authors are aware of only one, very recent, prospective risk factor study examining the effect of lumbo-pelvic motion during sprinting on hamstring injury risk. Furthermore, the interventions exploring the effect of lumbo-pelvic training on hamstring injury rates have not measured stability in any way. An improved understanding of the evidence underpinning commonly employed hamstring injury prevention practices may enable clinicians and coaches to better prioritise effective strategies in the increasingly complex environment of elite sport.

Limb Mass And Passive Muscle Tension Contributions To Knee Flexion Torque At Long Muscle Lengths

PURPOSE: During isokinetic and isometric strength testing it is important to correct torque for the contribution of limb mass and passive muscle tension. This is particularly important in testing hamstring strength since weakness at long muscle lengths is a factor in recurrent hamstring strains. The purpose of this study was to quantify the relative contributions of passive muscle tension and limb mass during strength testing with the hamstrings in a stretched position. METHODS: Isometric strength tests were performed on 50 athletes (30 men, 20 women) prior to return to sport after a hamstring strain. Strength was assessed at 80o, 60o, 40o, and 20o knee flexion in sitting with the test thigh flexed 40o above horizontal and the seat back at 90o to the horizontal. In this set up the leg was horizontal at 50o knee flexion. Passive torque (limb mass + passive hamstring tension) was recorded at each angle. Passive torque at 80o was defined as limb mass with no muscle tension; limb mass at 80o and 20 o were equal (30o below/above horizontal); limb mass at 60o and 40o were calculated [(passive torque at 80o/cos 30o) *cos 10o]. Torque due to passive muscle tension = measured passive torque - limb mass. RESULTS: Passive muscle tension contributed 21%, of total torque at 20o with limb mass contributing 16% and contractile torque accounting for only 63% of total torque. Angle of peak torque occurred at a significantly shorter muscle length (P<0.01) when calculated from contractile torque (62o) versus total torque (49o).Table: No title available.Conclusions: Currently “gravity correction” functions for isokinetic testing measure passive torque at only one joint angle and therefore cannot account for changing passive muscle tension from short to long muscle lengths. This invalidates isokinetic assessment of hamstring angle of peak torque or weakness at long muscle lengths where passive muscle tension is considerable.

THE EFFECT OF EXERCISE PRESCRIPTION ON FORCE OUTPUT AND MUSCLE ACTIVATION DURING THE NORDIC HAMSTRING EXERCISE

BackgroundThe Nordic hamstring exercise (NHE) is employed to increase eccentric strength and reduce the risk of recurrent hamstring strain injury. Currently, the prescription of the NHE offering most benefit is...

Epidemiology of Hamstring Strains in 25 NCAA Sports in the 2009-2010 to 2013-2014 Academic Years

Background: The epidemiology of hamstring strains among student-athletes has been extensively researched. However, there is a paucity of recent data describing patterns of hamstring strains. Purpose: To describe the epidemiology of hamstring strains in 25 National Collegiate Athletic Association (NCAA) championship sports. Study Design: Descriptive epidemiology study. Methods: Hamstring strains data were analyzed from the NCAA Injury Surveillance Program during the 2009-2010 to 2013-2014 academic years. Hamstring strain injury rates, rate ratios (RRs), and injury proportion ratios were reported with 95% CIs. Results: During the study period, 1142 hamstring strains were reported, leading to an injury rate of 3.05 per 10,000 athlete-exposures (AEs). Most hamstring strains occurred during practices (68.2%). However, the competition rate (5.24 per 10,000 AEs) was larger than the practice rate (2.56 per 10,000 AEs; RR = 2.05; 95% CI, 1.81-2.32). A slight majority occurred during the regular season (52.9%). However, the preseason rate (5.00 per 10,000 AEs) was larger than the regular season/postseason rate (2.34 per 10,000 AEs; RR = 2.14; 95% CI, 1.90-2.40). Men’s football, men’s soccer, and women’s soccer contributed the greatest proportion of hamstring strains (35.3%, 9.9%, and 8.3%, respectively). Most hamstring strains were due to noncontact (72.3%). Of all hamstring strains, 12.6% were recurrent, 37.7% resulted in a time loss of <24 hours, and 6.3% resulted in a time loss >3 weeks. Variations in hamstring strain patterns existed by sport. The hamstring strain rate was larger in men than in women in soccer (RR = 1.60; 95% CI, 1.22-2.11), baseball/softball (RR = 1.66; 95% CI, 1.07-2.59), and indoor track (RR = 1.88; 95% CI, 1.26-2.78). In addition, proportions of hamstring strains that were recurrent were higher among men in most sex-comparable sports, but this difference was not significant. Conclusion: Hamstring strain rates were higher in the preseason and in competition. Student-athletes should be acclimatized to the rigors of preseason participation. Meanwhile, further surveillance should investigate the effectiveness of prospective prevention programs in an effort to reduce the prevalence of initial and recurrent hamstring strain injuries.

Examination and management considerations in the chronic, recurrent hamstring strain

Chronic hamstring injuries are widely acknowledged as requiring a multi-factorial approach to their management. This practical workshop will explore both common and unusual clinical presentations that have been shared with other practitioners in a high performance setting. This has highlighted the need for an individualised approach to management approaches. Emerging awareness of anatomical deficits as well as varied clinical presentations of motor patterning anomalies will be explored, along with the more common muscle strength issues and kinetic chain considerations.

Comparison of Hamstring Strain Injury Rates Between Male and Female Intercollegiate Soccer Athletes

Background: Hamstring strains are common among soccer athletes, and they have a high incidence of recurrence. Among American collegiate soccer players, men have an overall higher incidence rate of hamstring strains than women. Purpose: This research compares the hamstring strain injury rates in event and athlete characteristics between male and female college soccer athletes. Study Design: Descriptive epidemiology study. Methods: Data describing partial and complete hamstring strains were obtained from the National Collegiate Athletic Association (NCAA) Injury Surveillance System (ISS) for men’s and women’s soccer from 2004 to 2009. Incidence rate ratios (IRRs) comparing the incidence of hamstring strains between the sexes as well as during games versus practices and the preseason versus the in-season were calculated. χ2 tests were used to compare the occurrence of hamstring strains across different event and athlete characteristics. Results: Men were 64% more likely than women to sustain a hamstring strain (IRR, 1.64; 95% CI, 1.37-1.96). Men had significantly higher rates of hamstring strains than women during both games (IRR, 2.42; 95% CI, 1.82-3.23) and practices (IRR, 1.34; 95% CI, 1.06-1.68). There were no differences between men and women in injury rates during the preseason, but men were significantly more likely to sustain a hamstring strain during the in-season (IRR, 1.98; 95% CI, 1.56-2.52). Men had a significantly higher proportion of recurrent hamstring strains compared with women (men, 22%; women, 12%; P = .003). There were no significant differences in the distribution of strains in event or athlete characteristics between men and women for first-time or recurrent hamstring strains. Conclusion: In collegiate soccer, men have significantly higher rates of hamstring strains than women, and regardless of the recurrence status, the event and athlete characteristics were similar for both sexes. Identifying common characteristics may assist in the targeted development of preventive and rehabilitative programs as well as continued research on hamstring strains among collegiate soccer players.

Editor's Note

Welcome to the Sports Medicine Special Topics Issue of the Strength and Conditioning Journal. In keeping with the journal's mission, this issue features articles from outstanding experts in the field presenting the latest evidence-based and practical applications on a variety of sports medicine topics. This issue contributes to the ever-growing knowledge base required of strength and conditioning professionals seeking to safely and effectively progress the training regimens of their athletes and clients while recognizing the need to be aware of common injuries and prevention strategies. Given the continuum of care after injury, it is essential that strength and conditioning professionals at all levels possess knowledge of risks specific to common medical interventions and rehabilitation procedures. Moreover, we recognize that open and clear communication between medical professionals and strength and conditioning professionals is critical, particularly at the time of transition from medical care. In this issue, 2 articles address sport and exercise injury rates, with one addressing the latest findings on high school and college sport-specific injuries while the other article presents the incidence and risk factors for and prevention strategies for youth resistance training injuries. Five articles focus on foundational concepts, testing issues, injury prevention, and/or special considerations for exercise technique and program design in dealing with common joint-specific injuries or impairments. These evidence-based and practical application-specific articles address postrehabilitation strength and conditioning for the shoulder, prevention of recurrent hamstring strains, exercise and training considerations for neck pain, an overview of total knee replacement and the role of the strength and conditioning professional, and techniques for preventing anterior cruciate ligament injuries in female athletes. Other sports medicine current issues we expect you will find both intriguing and useful are presented in specific articles addressing exercise guidelines for pregnant and postpartum women; proprioception and how it is affected by injury, rehabilitation, and training; and the role of instability rehabilitative resistance training for the core musculature. We would like to thank all authors in graciously accepting the invitation to write for this special issue and their extensive work in preparing and revising their articles in a timely manner to meet all deadlines. Our thanks also go to the reviewers who provided valuable insight and comments on the articles. Last, we recognize Dr. Jeff Chandler for his support and for developing the idea of publishing a Sports Medicine Special Topics Issue and to Managing Editor Britt Chandler for always providing prompt editorial support. Whether you are a physical therapist, athletic trainer, personal trainer, strength coach, or other health professional working in the strength and conditioning field, we entrust you will find this issue informative and useful in your particular area of practice. Respectfully,Caption not available.John P. McCarthyCaption not available.Morey J. Kolber Guest Editors—Special Topics Issue on Sports Medicine

Perceived risk factors for hamstring muscle strain injuries in the Australian Football League (AFL)

Introduction: Hamstring muscle strain injuries are a significant problem in the AFL and research to date has demonstrated that the cause of such injuries is complicated and multi-factorial. The lack of a clear understanding of the risk factors associated with hamstring strains may be a feature in the high rate of hamstring strain incidence and recurrence. The purpose of this study was to survey the physiotherapists of all AFL clubs to understand their perceptions of risk factors for first-time and recurrent hamstring strain.

Magnetic Resonance Imaging Parameters for Assessing Risk of Recurrent Hamstring Injuries in Elite Athletes

Background Magnetic resonance (MR) imaging has established its usefulness in diagnosing hamstring muscle strain and identifying features correlating with the duration of rehabilitation in athletes; however, data are currently lacking that may predict which imaging parameters may be predictive of a repeat strain. Purpose This study was conducted to identify whether any MR imaging-identifiable parameters are predictive of athletes at risk of sustaining a recurrent hamstring strain in the same playing season. Study Design Cohort study; Level of evidence, 3. Methods Forty-one players of the Australian Football League who sustained a hamstring injury underwent MR examination within 3 days of injury between February and August 2002. The imaging parameters measured were the length of injury, cross-sectional area, the specific muscle involved, and the location of the injury within the muscle-tendon unit. Players who suffered a repeat injury during the same season were reimaged, and baseline and repeat injury measurements were compared. Comparison was also made between this group and those who sustained a single strain. Results Forty-one players sustained hamstring strains that were positive on MR imaging, with 31 injured once and 10 suffering a second injury. The mean length of hamstring muscle injury for the isolated group was 83.4 mm, compared with 98.7 mm for the reinjury group (P = .35). In the reinjury group, the second strain was also of greater length than the original (mean, 107.5 mm; P = .07). Ninety percent of players sustaining a repeat injury demonstrated an injury length greater than 60 mm, compared with only 58% in the single strain group (P = .01). Only 7% of players (1 of 14) with a strain <60 mm suffered a repeat injury. Of the 27 players sustaining a hamstring strain >60 mm, 33% (9 of 27) suffered a repeat injury. Of all the parameters assessed, only a history of anterior cruciate ligament sprain was a statistically significant predictor for suffering a second strain during the same season of competition. Conclusion A history of anterior cruciate ligament injury was the only statistically significant risk factor for a recurrent hamstring strain in our study. Of the imaging parameters, the MR length of a strain had the strongest correlation association with a repeat hamstring strain and therefore may assist in identifying which athletes are more likely to suffer further reinjury.

Bilateral and Recurrent Myositis Ossificans in an Athlete: A Case Report and Review of Treatment Options

Miller AE, Davis BA, Beckley OA. Bilateral and recurrent myositis ossificans in an athlete: a case report and review of treatment options. An unusual case of recurrent myositis ossificans (MO) bilaterally in the hamstring muscles of a 47-year-old athlete secondary to trauma is presented with a review of the literature of current treatment options. MO is a common condition that occurs among athletes in association with muscle and/or tendon strain or contusion. After an extensive literature review, we believe this to be the first case reported of recurrent and bilateral MO in a nonsurgical setting from recurrent hamstring strains. Plain radiographs and physical examination revealed the appearance and chronology of this pathology. Treatment options to improve flexibility and decrease morbidity are discussed along with prophylaxis for future injury. Treatment of mobility and flexibility, rehabilitation goals and treatment with nonsteroidal anti-inflammatory drugs, bisphosphonates, and magnesium are discussed along with prophylaxis.

The Football Association Medical Research Programme: an audit of injuries in professional football—analysis of hamstring injuries

Objective: To conduct a detailed analysis of hamstring injuries sustained in English professional football over two competitive seasons. Methods: Club medical staff at 91 professional football clubs annotated player injuries...

An Analysis of Hamstring Strains and Their Rehabilitation

The recurrent hamstring strain is a problem that is dealt with at all levels of athletics. The complex action of the hamstrings, as evident by EMG data, as well as a poor understanding of the mechanism of injury, are possible reasons for this high rate of reinjury. Another possible cause deals with the rehabilitation protocol utilized in treating this injury. Early controlled motion and specific exercises designed to apply to the unique characteristics of the hamstring muscles are necessary to completely rehabilitate the athlete and successfully prevent a recurrence. This program must include a progressive resumption of activity with an emphasis on high speed movements. A model hamstring rehabilitation program is proposed. J Orthop Sports Phys Ther 1987;9(2):77-85.