PREVALENCE OF HAMSTRING INJURIES IN SUMMER LEAGUE BASEBALL PLAYERS.

BACKGROUND AND PURPOSE: Hamstring injuries (HSI) occur more commonly in baseball than are often appreciated and can impact the potential career of a player. Little is known about the historical incidence of these injuries in summer league players preparing for their upcoming collegiate season or being drafted by major league team(s). Summer league baseball players have a high historical incidence of HSI which are often unknown at the start of their summer league play. The purpose of this study was to administer a validated questionnaire to assess various factors regarding the prevalence of prior hamstring injuries, current symptoms of posterior thigh pain or hamstring injuries in amateur summer league baseball players, and to provide details on the injury history, time lost from injury, injury reocurrence, position, individual player physical characteristics and physical activities that might be associated with those injuries. STUDY DESIGN: Cross-sectional Observational Study. METHOD: A self-reported, validated questionnaire regarding the history, prevalence, reoccurrence and functional impact of HSI and posterior thigh pain was administered to and completed by 201 out of 251 summer league baseball players associated with the Cape Cod League and the Northwoods League at the start of the 2013-2015 seasons. The questionnaire was administered by certified athletic trainers associated with each team. Participation was voluntary and informed consent was obtained from all players. RESULTS: Forty seven out of 201 players surveyed reported a HSI history. Sixty-six percent of these players (N = 31) reported unilateral injuries and 34% (N = 16) reported bilateral injuries. Reoccurrence rate was 27.7% across all players. Approximately 1/3rd of all position players (catchers 33.3%, infielders 32.6% and outfielders 31.6%) reported a HSI history compared to 12.9% of all pitchers. Significant differences (p<.05) existed between the HSI and Non-HSI groups for self-reported symptoms, soreness, and pain, as well as function and quality of life. Within the HSI history group, players who batted left and threw right reported the most injuries. CONCLUSION: A large number of position players and pitchers who report for summer league baseball have a history of posterior thigh pain and HSI. Those with prior injuries have a high reoccurrence rate. Position players have a higher incidence of injury than do pitchers. LEVEL OF EVIDENCE: 3.

Defending Puts the Anterior Cruciate Ligament at Risk During Soccer: A Gender-Based Analysis.

BACKGROUND: Soccer athletes are at risk for anterior cruciate ligament (ACL) injury. To date, there are limited studies on the mechanisms of ACL injuries in soccer athletes and no video-based analysis or sex-based comparison of these mechanisms. HYPOTHESIS: There is no difference in ACL injury mechanisms among soccer athletes by sex. STUDY DESIGN: Case series. LEVEL OF EVIDENCE: Level 4. METHODS: Fifty-five videos of ACL injuries in 32 male and 23 female soccer players were reviewed. Most athletes were professionals (22 males, 4 females) or collegiate players (8 males, 14 females). Visual analysis of each case was performed to describe the injury mechanisms in detail (game situation, player behavior, and lower extremity alignment). RESULTS: The majority of ACL injuries occurred when the opposing team had the ball and the injured athlete was defending (73%). Females were more likely to be defending when they injured their ACLs (87% vs 63% for males, P = 0.045). The most common playing action was tackling (51%), followed by cutting (15%). Most injuries occurred due to a contact mechanism (56%) with no significant difference for sex. Females were more likely to suffer a noncontact injury in their left knee (54%) than males (33%) (P = 0.05). CONCLUSION: Soccer players are at greatest risk for ACL injury when defending, especially when tackling the opponent in an attempt to win possession of the ball. Females are more likely to injure their ACLs when defending and are at greater risk for noncontact injuries in their left lower extremity. CLINICAL RELEVANCE: Soccer ACL injury prevention programs should include proper defending and tackling techniques, particularly for female athletes.

Doha agreement meeting on terminology and definitions in groin pain in athletes.

BACKGROUND: Heterogeneous taxonomy of groin injuries in athletes adds confusion to this complicated area. AIM: The 'Doha agreement meeting on terminology and definitions in groin pain in athletes' was convened to attempt to resolve this problem. Our aim was to agree on a standard terminology, along with accompanying definitions. METHODS: A one-day agreement meeting was held on 4 November 2014. Twenty-four international experts from 14 different countries participated. Systematic reviews were performed to give an up-to-date synthesis of the current evidence on major topics concerning groin pain in athletes. All members participated in a Delphi questionnaire prior to the meeting. RESULTS: Unanimous agreement was reached on the following terminology. The classification system has three major subheadings of groin pain in athletes: 1. Defined clinical entities for groin pain: Adductor-related, iliopsoas-related, inguinal-related and pubic-related groin pain. 2. Hip-related groin pain. 3. Other causes of groin pain in athletes. The definitions are included in this paper. CONCLUSIONS: The Doha agreement meeting on terminology and definitions in groin pain in athletes reached a consensus on a clinically based taxonomy using three major categories. These definitions and terminology are based on history and physical examination to categorise athletes, making it simple and suitable for both clinical practice and research.

An interval kicking progression for return to soccer following lower extremity injury.

BACKGROUND AND PURPOSE: The majority of all soccer injuries affect the lower extremities. Regardless of whether the injured limb is an athlete's preferred kicking or stance leg, a lower extremity injury may affect their ability to impact the ball. Sport-specific biomechanical progressions to augment loading and gradually reintroduce a player to the demands of sport have been developed for upper extremity sports such as baseball, softball, tennis, and golf. Generalized return to soccer progressions have also been published in order to assist clinicians in safely returning athletes to sport; however, there are no specific progressions for the early stages of kicking designed to introduce stance leg loading and kicking leg impact. Thus, the purpose of this clinical commentary was to review the existing literature elucidating the biomechanics of kicking a soccer ball and propose a progressive kicking program to support clinicians in safely returning their soccer athletes to the demands of sport. DESCRIPTION OF TOPIC: The interval kicking program (IKP) describes clinical guidelines for readiness to begin a kicking program as well as possible readiness to return to sport measures. The program is performed on alternate days integrating therapeutic exercise and cardiovascular fitness. The IKP gradually introduces a player to the loading and impact of kicking. The progression increases kicking distance (using the markings of a soccer field as a guide), volume, and intensity and uses proposed soreness rules, effusion guidelines, and player feedback in order to assist clinicians in determining readiness for advancement though the stages. The IKP also recommends utility of specific tests and measures to determine readiness for return to sport. DISCUSSION: Gradual reintroduction to sport specific demands is essential for a safe return to soccer. This return to sport progression provides a framework integrating injury specific therapeutic exercise, cardiovascular fitness, and the return to kicking progression, to assist clinicians in initiating an athletes' return to soccer. LEVEL OF EVIDENCE: Level 5.

Viscosupplementation during rehabilitation.

CONTEXT: Viscosupplementation (VS) and physical therapy are both used to treat pain associated with knee osteoarthritis (OA). EVIDENCE ACQUISITION: PubMed and EMBASE searches were performed to July 2013. Search terms included hyaluronic acid OR hylan, physical therapy OR exercise, AND osteoarthritis. STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 4. RESULTS: The efficacy and safety of VS in painful knee OA is well documented, as are the appropriate candidates for this intervention. Studies suggest that adding VS to physical therapy and therapeutic exercise may lead to improved pain reduction and increased functionality compared with physical therapy alone. CONCLUSION: Appropriately selected patients undergoing physical therapy for knee OA may benefit from VS.

Return to competitive football after major knee surgery: more questions than answers?

Despite significant advances in the diagnostics and treatment of knee injuries over the last decade, several challenges related to the subject "return to sport" remain largely unknown. For example, how should "return to sport" be defined precisely? What is the optimal timing and progression to enable a return to sport? Which criteria should be used during this process? What type of training is indicated? Which measurements can support the decision-making process? How do we optimally prepare athletes for competition without risking re-injury? This paper critically addresses these questions, and proposes a return to play model to prepare football players to compete after major knee surgery (anterior cruciate ligament reconstruction, cartilage repair). The goal is to re-integrate the player gradually into the game, taking into account his individual characteristics. Several evidence-based and empirical criteria are needed to plan and monitor the efficient return to competitive football. Injury-prevention education should be part of this process to maximise the chance of a durable career and decrease the risk of re-injury. However, because of the paucity of research on "return to sport", further research is more than warranted.

Popliteus strain with concurrent deltoid ligament sprain in an elite soccer athlete: a case report.

STUDY DESIGN: Case Report (Differential diagnosis). BACKGROUND AND PURPOSE: Differential diagnosis of knee pathology after trauma may be difficult when diagnosing an isolated popliteus strain and concurrent medial deltoid ligament sprain. Upon a thorough search of the published literature, the authors found no reports delineating a popliteus strain in professional soccer in the United States. The joints most affected by injury in soccer players are the knee and ankle joints. The purpose of this case report is to describe the presentation of and difficulties encountered in diagnosing a popliteus strain in a Major League Soccer athlete. CASE DESCRIPTION: During an in-season away game, an outside defender was slide-tackled from behind when his right shank was caught in an externally rotated position underneath himself and the opposing player. The initial point of contact was made to the proximal third of the posterior right shank with an anteromedially directed force. The medial longitudinal arch of the foot was forced into a more midfoot pronated position and the subtalar joint was forced into eversion. DIAGNOSIS: The athlete was diagnosed with a moderate strain of the right popliteus muscle with a concurrent medial deltoid ligament sprain of the right ankle. This mechanism of injury, pain with passive knee flexion and internal rotation during McMurray's test, pain with Garrick's Test and magnetic resonance imaging (MRI) study confirmed the diagnosis. The athlete returned to full ninety-minute game participation after an intensive 15-day rehabilitation program. DISCUSSION: This case is unique because the injury manifested itself at multiple joints and specifically involved the popliteus muscle. The mechanism of injury can be associated with many other soft tissue injuries to the knee, and thus, may not lead the clinician initially to consider the diagnosis of a popliteus strain. Diagnosis of this entity may be difficult due to the possible shared attachment of the popliteus muscle to the lateral meniscus, and the lack of available testing methods to assess damage to the popliteus muscle. LEVEL OF EVIDENCE: Level 5.

Current concepts for rehabilitation and return to sport after knee articular cartilage repair in the athlete.

Articular cartilage injury is observed with increasing frequency in both elite and amateur athletes and results from the significant acute and chronic joint stress associated with impact sports. Left untreated, articular cartilage defects can lead to chronic joint degeneration and athletic and functional disability. Treatment of articular cartilage defects in the athletic population presents a therapeutic challenge due to the high mechanical demands of athletic activity. Several articular cartilage repair techniques have been shown to successfully restore articular cartilage surfaces and allow athletes to return to high-impact sports. Postoperative rehabilitation is a critical component of the treatment process for athletic articular cartilage injury and should take into consideration the biology of the cartilage repair technique, cartilage defect characteristics, and each athlete's sport-specific demands to optimize functional outcome. Systematic, stepwise rehabilitation with criteria-based progression is recommended for an individualized rehabilitation of each athlete not only to achieve initial return to sport at the preinjury level but also to continue sports participation and reduce risk for reinjury or joint degeneration under the high mechanical demands of athletic activity.

The prevalence of radiographic hip abnormalities in elite soccer players.

BACKGROUND: Hip injuries, both intra- and extra-articular, are becoming a more commonly recognized, diagnosed, and treated injury in athletes of all competitive levels. Our goal is to establish a previously undefined value in this athletic population--the prevalence of radiographic hip abnormalities in elite soccer athletes. PURPOSE: To provide a foundation for the future body of literature regarding hip pathologic abnormalities and "at-risk" hips in athletes of all ages and levels of participation. STUDY DESIGN: Descriptive epidemiology study. METHODS: We retrospectively reviewed the anteroposterior pelvis and frog-leg lateral radiographs of 95 elite male and female soccer players to determine the prevalence of hip abnormalities. Athletes with a history of hip or groin injuries were included. Multiple radiographic parameters were used to assess the presence of cam and pincer-type femoroacetabular impingement. Measurements were conducted by a blinded, sports medicine fellowship-trained orthopaedic surgeon with experience in treating hip disorders. RESULTS: In total, 72% (54/75) of male and 50% (10/20) of female players demonstrated some evidence of radiographic hip abnormality. Cam lesions were present in 68% (51/75) of men (76.5% [39/51] bilateral involvement) and 50% (10/20) of women (90% [9/10] bilateral involvement). Pincer lesions were present in 26.7% (20/75) of men and 10% (2/20) of women. The average male alpha angle overall was 65.6°. Cam-positive hips averaged 70.7°. The average female alpha angle overall was 52.9°, with cam-positive hips averaging 60.8°. CONCLUSION: The prevalence of radiographic hip abnormalities in elite soccer athletes is considerable, particularly in young male athletes. The establishment of the prevalence of these findings represents the first step in identifying the relationship between radiographic abnormalities and injuries of the hip and groin in athletes.

Rehabilitation after Articular Cartilage Repair of the Knee in the Football (Soccer) Player.

BACKGROUND: Participation in football can put both male and female players at an increased risk for knee osteoarthritis. There is a higher prevalence of focal chondral defects in the knee of athletes compared to nonathletes. The management of chondral defects in the football player is complex and multifactorial. OBJECTIVE: The aim of this study is to provide an overview of the current strategies for rehabilitation after articular cartilage repair of the knee in the football player. DESIGN: A review of current literature and the scientific evidence for rehabilitation after articular cartilage repair of the knee. CONCLUSIONS: Articular cartilage repair has been shown to allow return to sport but rehabilitation timescales are lengthy. Successful rehabilitation for a return to football after articular cartilage repair of the knee requires the player to be able to accept the load of the sport. This necessitates a multidisciplinary approach to rehabilitation, especially in the transition from therapy to performance care. It should be recognized that not all players will return to football after articular cartilage repair. The evidence base for rehabilitative practice after articular cartilage repair is increasing but remains sparse in areas.

Gender influences: the role of leg dominance in ACL injury among soccer players.

OBJECTIVE: This study intends to look at the role of leg dominance in anterior cruciate ligament (ACL) injury risk among soccer (football) athletes. The purpose of this study was to test the hypothesis that soccer players rupture the ACL of their preferred support leg more frequently than the ACL in their preferred kicking leg, particularly in non-contact injuries, despite differences in gender. DESIGN: Retrospective observational study. SETTING: Outpatient orthopaedic practice. PATIENTS: Subjects who had sustained an ACL injury due to direct participation in soccer. N=93 (41 male, 52 female). INTERVENTIONS: These noncontact injuries were sustained while playing soccer. RESULTS: For non-contact injuries, roughly half of the injuries occurred in the preferred kicking leg (30) and the contralateral leg (28). However, by gender, there was a significant difference in the distribution of non-contact injury, as 74.1% of males (20/27) were injured on the dominant kicking leg compared with 32% (10/31) of females (p<0.002). CONCLUSIONS: When limited to a non-contact injury mechanism, females are more likely to injure the ACL in their supporting leg, whereas males tend to injure their kicking leg. This research suggests that limb dominance does serve as an aetiological factor with regard to ACL injuries sustained while playing soccer. If follow-up studies confirm that females are more likely to injure their preferred supporting leg, future research should investigate the cause for this discrepancy, which could result from underlying gender-based anatomical differences as well as differences in neuromuscular patterns during cutting manoeuvres or kicking.

Anterior cruciate ligament injuries: etiology and prevention.

The relatively high risk of noncontact anterior cruciate ligament (ACL) rupture among female athletes has been a major impetus for investigation into the etiology of this injury. A number of risk factors have been identified, both internal and external to the athlete, including neuromuscular, anatomical, hormonal, shoe-surface interaction, and environmental, such as weather. The anatomic and neuromuscular risk factors, often gender related, are the focus of most ACL injury prevention programs. Although studies have shown that biomechanic- centered prevention programs can reduce the risk of ACL injury, many questions remain unanswered. More research is needed to increase our understanding of the risk factors for ACL injury; how injury prevention programs work and can the clinical application of such programs be optimized.

Groin injuries in sports medicine.

CONTEXT: An in-season groin injury may be debilitating for the athlete. Proper diagnosis and identification of the pathology are paramount in providing appropriate intervention. Furthermore, an adductor strain that is treated improperly can become chronic and career threatening. Any one of the 6 muscles of the adductor muscle group can be involved. The degree of injury can range from a minor strain (grade 1), where minimal playing time is lost, to a severe strain (grade 3), in which there is complete loss of muscle function. Persistent groin pain and muscle imbalance may lead to athletic pubalgia. EVIDENCE ACQUISITION: Relevant studies were identified through a literature search of MEDLINE and the Cochrane database from 1990 to 2009, as well as a manual review of reference lists of identified sources. RESULTS: Ice hockey and soccer players seem particularly susceptible to adductor muscle strains. In professional ice hockey and soccer players throughout the world, approximately 10% to 11% of all injuries are groin strains. These injuries have been linked to hip muscle weakness, a previous injury to that area, preseason practice sessions, and level of experience. This injury may be prevented if these risk factors are addressed before each season. CONCLUSION: Despite the identification of risk factors and strengthening intervention for athletes, adductor strains continue to occur throughout sport. If groin pain persists, the possibility of athletic pubalgia needs to be explored, because of weakening or tears in the abdominal wall muscles. A diagnosis is confirmed by exclusion of other pathology.

Injection of platelet-rich plasma in patients with primary and secondary knee osteoarthritis: a pilot study.

OBJECTIVE: To evaluate the clinical effects of intraarticular platelet-rich plasma (PRP) injections in a small group of patients with primary and secondary osteoarthritis. Most of the current treatments for osteoarthritis are palliative and attack the symptoms rather than influencing the biochemical environment of the joint. Autologous platelet-rich plasma has emerged as a treatment option for tendinopathies and chronic wounds. In addition to release of growth factors, platelet-rich plasma also promotes concentrated anti-inflammatory signals including interleukin-1ra, which has been a focus of emerging treatments for osteoarthritis. DESIGN: In this single-center, uncontrolled, prospective preliminary study, 14 patients with primary and secondary knee osteoarthritis who met the study criteria received three platelet-rich plasma injections in the affected knee at ∼4-wk intervals. Outcome measures included the Brittberg-Peterson Visual Pain (Visual Analog Scale [VAS]), Activities, and Expectations score and the Knee Injury and Osteoarthritis Outcome Scores at preinjection visit at 2-, 5-, 11-, 18-, and 52-wk follow-up visits. Musculoskeletal ultrasound was used to measure cartilage thickness. RESULTS: There were no adverse events reported. The study demonstrated significant and almost linear improvements in Knee Injury and Osteoarthritis Outcome Scores, including pain and symptom relief. Brittberg-Peterson VAS showed many improvements including reduced pain after knee movement and at rest. Cartilage assessment was limited because of the small sample size. The majority of the patients expressed a favorable outcome at 12 mos after treatment. CONCLUSIONS: The positive trends and safety profile demonstrated could potentially be used to inspire a larger, blinded, and randomized clinical trial to determine whether platelet-rich plasma is safe and effective for the treatment of knee osteoarthritis.

Return to sports participation after articular cartilage repair in the knee: scientific evidence.

BACKGROUND: Articular cartilage injury in the athlete's knee presents a difficult clinical challenge. Despite the importance of returning injured athletes to sports, information is limited on whether full sports participation can be successfully achieved after articular cartilage repair in the knee. HYPOTHESIS: Systematic analysis of athletic participation after articular cartilage repair will demonstrate the efficacy of joint surface restoration in high-demand patients and help to optimize outcomes in athletes with articular cartilage injury of the knee. STUDY DESIGN: Systematic review. METHODS: A comprehensive literature review of original studies was performed to provide information about athletic participation after articular cartilage repair. The athlete's ability to perform sports postoperatively was assessed by activity outcome scores, rate of return to sport, timing of the return, level of postoperative sports participation, and the continuation of athletic activity over time. RESULTS: Twenty studies describing 1363 patients were included in the review, with an average follow-up of 42 months. Return to sports was possible in 73% overall, with highest return rates after osteochondral autograft transplantation. Time to return to sports varied between 7 and 18 months, depending on the cartilage repair technique. Initial return to sports at the preinjury level was possible in 68% and did not significantly vary between surgical techniques. Continued sports participation at the preinjury level was possible in 65%, with the best durability after autologous chondrocyte transplantation. Several factors affected the ability to return to sport: athlete's age, preoperative duration of symptoms, level of play, lesion size, and repair tissue morphology. CONCLUSION: Articular cartilage repair in the athletic population allows for a high rate of return to sports, often at the preinjury level. Return to sports participation is influenced by several independent factors. The findings provide pertinent information that is helpful for the clinical decision-making process and for the management of the athlete's postoperative expectations.

Prevention of non-contact anterior cruciate ligament injuries in soccer players. Part 2: a review of prevention programs aimed to modify risk factors and to reduce injury rates.

Soccer is the most commonly played sport in the world, with an estimated 265 million active soccer players participating in the game as on 2006. Inherent to this sport is the higher risk of injury to the anterior cruciate ligament (ACL) relative to other sports. ACL injury causes a significant loss of time from competition in soccer, which has served as the strong impetus to conduct research that focuses to determine the risk factors for injury, and more importantly, to identify and teach techniques to reduce this injury in the sport. This research emphasis has afforded a rapid influx of literature aimed to report the effects of neuromuscular training on the risk factors and the incidence of non-contact ACL injury in high-risk soccer populations. The purpose of the current review is to sequence the most recent literature relating the effects of prevention programs that were developed to alter risk factors associated with non-contact ACL injuries and to reduce the rate of non-contact ACL injuries in soccer players. To date there is no standardized intervention program established for soccer to prevent non-contact ACL injuries. Multi-component programs show better results than single-component preventive programs to reduce the risk and incidence of non-contact ACL injuries in soccer players. Lower extremity plyometrics, dynamic balance and strength, stretching, body awareness and decision-making, and targeted core and trunk control appear to be successful training components to reduce non-contact ACL injury risk factors (decrease landing forces, decrease varus/valgus moments, and increase effective muscle activation) and prevent non-contact ACL injuries in soccer players, especially in female athletes. Pre-season injury prevention combined with an in-season maintenance program may be advocated to prevent injury. Compliance may in fact be the limiting factor to the overall success of ACL injury interventions targeted to soccer players regardless of gender. Thus, interventional research must also consider techniques to improve compliance especially at the elite levels which will likely influence trickle down effects to sub-elite levels. Future research is also needed for male soccer athletes to help determine the most effective intervention to reduce the non-contact ACL injury risk factors and to prevent non-contact ACL injuries.

Prevention of non-contact anterior cruciate ligament injuries in soccer players. Part 1: Mechanisms of injury and underlying risk factors.

Soccer is the most commonly played sport in the world, with an estimated 265 million active soccer players by 2006. Inherent to this sport is the higher risk of injury to the anterior cruciate ligament (ACL) relative to other sports. ACL injury causes the most time lost from competition in soccer which has influenced a strong research focus to determine the risk factors for injury. This research emphasis has afforded a rapid influx of literature defining potential modifiable and non-modifiable risk factors that increase the risk of injury. The purpose of the current review is to sequence the most recent literature that reports potential mechanisms and risk factors for non-contact ACL injury in soccer players. Most ACL tears in soccer players are non-contact in nature. Common playing situations precluding a non-contact ACL injury include: change of direction or cutting maneuvers combined with deceleration, landing from a jump in or near full extension, and pivoting with knee near full extension and a planted foot. The most common non-contact ACL injury mechanism include a deceleration task with high knee internal extension torque (with or without perturbation) combined with dynamic valgus rotation with the body weight shifted over the injured leg and the plantar surface of the foot fixed flat on the playing surface. Potential extrinsic non-contact ACL injury risk factors include: dry weather and surface, and artificial surface instead of natural grass. Commonly purported intrinsic risk factors include: generalized and specific knee joint laxity, small and narrow intercondylar notch width (ratio of notch width to the diameter and cross sectional area of the ACL), pre-ovulatory phase of menstrual cycle in females not using oral contraceptives, decreased relative (to quadriceps) hamstring strength and recruitment, muscular fatigue by altering neuromuscular control, decreased "core" strength and proprioception, low trunk, hip, and knee flexion angles, and high dorsiflexion of the ankle when performing sport tasks, lateral trunk displacement and hip adduction combined with increased knee abduction moments (dynamic knee valgus), and increased hip internal rotation and tibial external rotation with or without foot pronation. The identified mechanisms and risk factors for non-contact ACL injuries have been mainly studied in female soccer players; thus, further research in male players is warranted. Non-contact ACL injuries in soccer players likely has a multi-factorial etiology. The identification of those athletes at increased risk may be a salient first step before designing and implementing specific pre-season and in-season training programs aimed to modify the identified risk factors and to decrease ACL injury rates. Current evidence indicates that this crucial step to prevent ACL injury is the only option to effectively prevent the sequelae of osteoarthritis associated with this traumatic injury.

Comprehensive warm-up programme to prevent injuries in young female footballers: cluster randomised controlled trial.

OBJECTIVE: To examine the effect of a comprehensive warm-up programme designed to reduce the risk of injuries in female youth football. DESIGN: Cluster randomised controlled trial with clubs as the unit of randomisation. SETTING: 125 football clubs from the south, east, and middle of Norway (65 clusters in the intervention group; 60 in the control group) followed for one league season (eight months). PARTICIPANTS: 1892 female players aged 13-17 (1055 players in the intervention group; 837 players in the control group). INTERVENTION: A comprehensive warm-up programme to improve strength, awareness, and neuromuscular control during static and dynamic movements. MAIN OUTCOME MEASURE: Injuries to the lower extremity (foot, ankle, lower leg, knee, thigh, groin, and hip). RESULTS: During one season, 264 players had relevant injuries: 121 players in the intervention group and 143 in the control group (rate ratio 0.71, 95% confidence interval 0.49 to 1.03). In the intervention group there was a significantly lower risk of injuries overall (0.68, 0.48 to 0.98), overuse injuries (0.47, 0.26 to 0.85), and severe injuries (0.55, 0.36 to 0.83). CONCLUSION: Though the primary outcome of reduction in lower extremity injury did not reach significance, the risk of severe injuries, overuse injuries, and injuries overall was reduced. This indicates that a structured warm-up programme can prevent injuries in young female football players. TRIAL REGISTRATION: ISRCTN10306290.

A randomized controlled trial to prevent noncontact anterior cruciate ligament injury in female collegiate soccer players.

BACKGROUND: Neuromuscular and proprioceptive training programs can decrease noncontact anterior cruciate ligament injuries; however, they may be difficult to implement within an entire team or the community at large. HYPOTHESIS: A simple on-field alternative warm-up program can reduce noncontact ACL injuries. STUDY DESIGN: Randomized controlled trial (clustered); Level of evidence, 1. METHODS: Participating National Collegiate Athletic Association Division I women's soccer teams were assigned randomly to intervention or control groups. Intervention teams were asked to perform the program 3 times per week during the fall 2002 season. All teams reported athletes' participation in games and practices and any knee injuries. Injury rates were calculated based on athlete exposures, expressed as rate per 1000 athlete exposures. A z statistic was used for rate ratio comparisons. RESULTS: Sixty-one teams with 1435 athletes completed the study (852 control athletes; 583 intervention). The overall anterior cruciate ligament injury rate among intervention athletes was 1.7 times less than in control athletes (0.199 vs 0.340; P = .198; 41% decrease). Noncontact anterior cruciate ligament injury rate among intervention athletes was 3.3 times less than in control athletes (0.057 vs 0.189; P = .066; 70% decrease). No anterior cruciate ligament injuries occurred among intervention athletes during practice versus 6 among control athletes (P = .014). Game-related noncontact anterior cruciate ligament injury rates in intervention athletes were reduced by more than half (0.233 vs 0.564; P = .218). Intervention athletes with a history of anterior cruciate ligament injury were significantly less likely to suffer another anterior cruciate ligament injury compared with control athletes with a similar history (P = .046 for noncontact injuries). CONCLUSION: This program, which focuses on neuromuscular control, appears to reduce the risk of anterior cruciate ligament injuries in collegiate female soccer players, especially those with a history of anterior cruciate ligament injury.