Intramuscular corticosteroid injection for hamstring injuries. A 13-year experience in the National Football League

Percutaneous Interventions for Injuries in Athletes: Implications on Return to Play

For nonsurgical musculoskeletal (MSK) injuries in athletes, image-guided percutaneous intervention may aid in recovery and decrease return to play (RTP) time. These interventions fall into two major categories: to reduce inflammation (and therefore alleviate pain) or to promote healing. This review describes the risks and benefits of the various percutaneous interventions in MSK athletic injury and surveys the literature regarding the implication of these interventions on RTP.

Traumatic muscle injury

Traumatic muscle injury represents a collection of skeletal muscle pathologies caused by trauma to the muscle tissue and is defined as damage to the muscle tissue that can result in a functional deficit. Traumatic muscle injury can affect people across the lifespan and can result from high stresses and strains to skeletal muscle tissue, often due to muscle activation while the muscle is lengthening, resulting in indirect and non-contact muscle injuries (strains or ruptures), or from external impact, resulting in direct muscle injuries (contusion or laceration). At a microscopic level, muscle fibres can repair focal damage but must be completely regenerated after full myofibre necrosis. The diagnosis of muscle injury is based on patient history and physical examination. Imaging may be indicated to eliminate differential diagnoses. The management of muscle injury has changed within the past 5 years from initial rest, immobilization and (over)protection to early activation and progressive loading using an active approach. One challenge of muscle injury management is that numerous medical treatment options, such as medications and injections, are often used or proposed to try to accelerate muscle recovery despite very limited efficacy evidence. Another challenge is the prevention of muscle injury owing to the multifactorial and complex nature of this injury.

Musculoskeletal Injury in American Football: A Bibliometric Analysis of the Most Cited Articles

Background

Textbook knowledge and clinical dogma are often insufficient for effective evidence-based decision making when treating musculoskeletal injuries in American football players, given the variability in presentation and outcomes across different sports and different levels of competition. Key evidence can be drawn directly from high-quality published articles to make the appropriate decisions and recommendations for each athlete's unique situation.

Purpose

To identify and analyze the 50 most cited articles related to football-related musculoskeletal injury to provide an efficient tool in the arsenal of trainees, researchers, and evidence-based practitioners alike.

Study Design

Cross-sectional study.

Methods

The ISI Web of Science and SCOPUS databases were queried for articles pertaining to musculoskeletal injury in American football. For each of the top 50 most cited articles, bibliometric elements were evaluated: citation count and density, decade of publication, journal, country, multiple publications by the same first author or senior author, article content (topic, injury area), and level of evidence (LOE).

Results

The mean ± SD number of citations was 102.76 ± 37.11; the most cited article, with 227 citations, was "Syndesmotic Ankle Sprains" published in 1991 by Boytim et al. Several authors served as a first or senior author on >1 publication, including J.S. Torg (n = 6), J.P. Bradley (n = 4), and J.W. Powell (n = 4). The American Journal of Sports Medicine published the majority of the 50 most cited articles (n = 31). A total of 29 articles discussed lower extremity injuries, while only 4 discussed upper extremity injuries. The majority of the articles (n = 28) had an LOE of 4, with only 1 article having an LOE of 1. The articles with an LOE of 3 had the highest mean citation number (133.67 ± 55.23; F = 4.02; P = .05).

Conclusion

The results of this study highlight the need for more prospective research surrounding the management of football-related injury. The low overall number of articles on upper extremity injury (n = 4) also highlights an area for further research.

London International Consensus and Delphi study on hamstring injuries part 2: operative management

The key indications for surgical repair of hamstring injuries (HSIs) remain unclear in the literature due to a lack of high-level evidence and expert knowledge. The 2020 London International Hamstring Consensus meeting aimed to highlight clear surgical indications and to create a foundation for future research. A literature review was conducted followed by a modified Delphi process, with an international expert panel. Purposive sampling was used with two rounds of online questionnaires and an intermediate round involving a consensus meeting. The initial information gathering (round 1) questionnaire was sent to 46 international experts, which comprised open-ended questions covering decision-making domains in HSI. Thematic analysis of responses outlined key domains, which were evaluated by a smaller international subgroup (n=15) comprising clinical academic sports medicine physicians, physiotherapists and orthopaedic surgeons in a consensus meeting. After group discussion of each domain, a series of consensus statements were prepared, debated and refined. A round 2 questionnaire was sent to 112 international hamstring experts to vote on these statements and determine level of agreement. The consensus threshold was set a priori at 70% agreement. Rounds 1 and 2 survey respondents were 35/46 (76%) and 99/112 (88.4%), respectively. The consensus group agreed that the indications for operative intervention included: gapping at the zone of tendinous injury (87.2% agreement) and loss of tension (70.7%); symptomatic displaced bony avulsions (72.8%); and proximal free tendon injuries with functional compromise refractory to non-operative treatment (72.2%). Other important considerations for operative intervention included: the demands of the athlete/patient and the expected functional outcome (87.1%) based on the anatomy of the injury; the risk of functional loss/performance deficit with non-operative management (72.2%); and the capacity to restore anatomy and function (87.1%). Further research is needed to determine whether surgery can reduce the risk of reinjury as consensus was not reached within the whole group (48.2%) but was agreed by surgeons (70%) in the cohort. The consensus group did not support the use of corticosteroids or endoscopic surgery without further evidence. These guidelines will help standardise treatment of HSIs, specifically the indications and decision-making for surgical intervention.

Hamstring Injuries: Critical Analysis Review of Current Nonoperative Treatments

➢

Hamstring injuries are common among active and athletic individuals, especially those involved in high-speed running, distance running, or sports requiring sudden directional changes. Acute hamstring strains often occur as an eccentric strain during running or a stretch-type injury caused by simultaneous hip flexion and knee extension. Proximal hamstring tendinopathy is an overuse injury of the hamstring tendon as a result of chronic cicatrization of the musculotendinous unit.

➢

Repeated stress to the hamstring tendon leads to increased cellularity of tendon fibers, disruption of collagen, and subsequent microinjury of the tissue that attaches the tendon to bone.

➢

Management of hamstring injuries generally begins with nonoperative modalities consisting of eccentric rehabilitative exercise programs. Although various other treatment modalities are available, the comparative efficacy of these supportive measures is not well differentiated at this time.

➢

In this article, we review the current literature with regard to the nonoperative treatment of hamstring injuries, specifically focusing on acute hamstring muscle strains and proximal hamstring tendinopathy in order to provide supplementary insight on the effectiveness of current modalities.

Anaesthesia for elite athletes

BACKGROUND

Sports participation has been growing rapidly since the 1960s. Anaesthesiologists are increasingly confronted with athletes in a peri-operative setting. The right choice of type of anaesthesia technique, pain management of injuries, specific physiologic adaptations of the athlete and knowledge of prohibited substances are eminent for a correct approach of this subpopulation.

PURPOSE

This review aims to give an overview of athletes' specific anaesthetic management in peri-operative and postoperative settings and to guide the nonspecialised anaesthetist.

METHODS

We comprehensively reviewed the literature, gathered all the information available on, and synthesised it in a narrative way, regarding preoperative evaluation, intraoperative implications and postoperative pain management of the elite athlete undergoing a surgical procedure.

RESULTS

An anaesthesiologist should recognise the most common benign ECG findings in athletes like bradycardia, isolated left ventricle hypertrophy on voltage criteria and early repolarisation as normal features in the athlete's heart. Isotonic physiology typically produces four-chamber dilation. In contrast, isometric stress creates high intravascular pressure leading to left ventricular hypertrophy. Pre-operative evaluation should also identify possible consumers of performance-enhancing drugs. Intraoperative points of interest for the anaesthesiologist is mainly avoiding drugs on the prohibited list of the World Anti-Doping Agency (WADA). Postoperative and chronic pain management are still developing fields in this population. The International Olympic Committee (IOC) proposed treating acute pain with a combination of paracetamol, non-steroidal anti-inflammatory drugs (NSAIDs), topical analgesics, injectable NSAIDs and local anaesthetics. It may be suggested that chronic pain management in elite athletes could benefit from treatment in specialised multidisciplinary pain clinics.

CONCLUSION

This literature review aims to serve as a guide for the anaesthesiologist taking care of the elite athlete.

Hamstring Strain Injury (HSI) Prevention in Professional and Semi-Professional Football Teams: A Systematic Review and Meta-Analysis

Hamstring Strain Injuries (HSIs) are the most common type of lesion in professional footballers and the leading cause of absence days from sports. However, recent studies have shown that high-level football teams apparently do not apply any HSI prevention protocol. The aim of the study was to determine the effect of preventive strategies and protocols in reducing the incidence of hamstring muscle injuries in professional and semi-professional football teams. A literature search of PubMed/MEDLINE, ISI/Web of Science and Scopus databases was conducted with the keywords “hamstring* and (injury* or strain) and prevent* and (soccer or football)”. Quality and bias assessment was completed through the Kennelly modified scale. The Injury Incidence Rate (IIR) and the Incidence Rate Ratio (IRR) were assessed in the statistical analysis. In the meta-analysis, data were extracted, pooled and analysed with “Comprehensive Meta-Analysis Version 3.3.070” software. In total, 8 of the 1017 original search studies met the inclusion criteria of this review. The total exposure of the studies was 170,221.8 h, while the number of HSIs recorded was 165 in the intervention groups and 224 in the control groups. The average score of the quality assessment was 23.6/34. The meta-analysis of six of the eight included studies provided strong evidence that interventions are effective in reducing hamstring injuries. The IRR of the effect size was 0.443, with p-value = 0.001. The studies analysed applied different preventive strategies: the Nordic hamstring exercise, the FIFA 11+ programme and exercises for core stability or balance training. All these interventions proved to have a successful effect on prevention of hamstring injuries.

Injectable Ketorolac and Corticosteroid Use in Athletes: A Systematic Review

CONTEXT

The use of injectable medications to help athletes quickly return to the field of play after injury is common. Understanding the effects and risks of these medications will help providers make informed decisions regarding their use in this patient population.

OBJECTIVE

To evaluate the utilization, efficacy, and adverse effects of injectable ketorolac and corticosteroids in athletes.

DATA SOURCES

This systematic review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A systematic search of the literature was performed using multiple databases (PubMed, Embase, Cochrane, Web of Science, and ClinicalTrials.gov). Secondary references were appraised for relevant articles. No randomized controlled trials or other prospective studies were identified. Articles included retrospective database reviews and physician survey studies.

STUDY SELECTION

A total of 6 studies met the inclusion and exclusion criteria and were reviewed by 2 independent reviewers with a third consulted in the case of disagreement, which was not needed.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 5.

DATA EXTRACTION

Two reviewers recorded rate of use, effectiveness of treatment, and reported side effect data.

RESULTS

Most studies centered around the football athlete, either professional or collegiate. Professional football game day use of intramuscular ketorolac declined from 93.3% (28/30) in 2002 to 48% in 2016. Collegiate football game day use of intramuscular ketorolac declined from 62% in 2008 to 26% in 2016. Game day corticosteroid injection was far lower than ketorolac usage. Both medications were reported to be effective with few adverse events.

CONCLUSION

Use of injectable ketorolac is common but declining in professional and college football. Pain control efficacy is good, and risk of adverse events is low. The incidence of injectable corticosteroid use in athletes is unknown. Use of injectable corticosteroids in athletes allows for early return to sport activities with no reported complications.

Platelet-Rich Plasma Shortens Return to Play in National Football League Players With Acute Hamstring Injuries

Background:

Hamstring injuries are prevalent in professional athletes and can lead to significant time loss, with recurrent injury being common. The efficacy of platelet-rich plasma (PRP) for augmentation of nonoperative treatment of partial musculotendinous hamstring injuries is not well established.

Hypothesis:

The addition of PRP injections to nonoperative treatment for acute partial musculotendinous hamstring injuries will lead to a shortened return to play in National Football League (NFL) players.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

NFL players from a single team who sustained acute grade 2 hamstring injuries, as diagnosed on magnetic resonance imaging (MRI) by a musculoskeletal radiologist from 2009 to 2018, were retrospectively reviewed. Average days, practices, and games missed were recorded. Players who did and did not receive PRP (leukocyte-poor) injections were compared. Those who received PRP did so within 24 to 48 hours after injury.

Results:

A total of 108 NFL players had MRI evidence of a hamstring injury, and of those, 69 athletes sustained grade 2 injuries. Thirty players received augmented treatment with PRP injections and 39 players underwent nonoperative treatment alone. Average time missed in those treated with PRP injections was 22.5 days, 18.2 practices, and 1.3 games. In those who did not receive PRP injections, time missed was 25.7 days (P = .81), 22.8 practices (P = .68), and 2.9 games (P < .05).

Conclusion:

Augmentation with PRP injections for acute grade 2 hamstring injuries in NFL players showed no significant difference in days missed or time to return to practice but did allow for faster return to play, with a 1 game overall difference. Owing to the possible large financial impact of returning to play 1 game sooner, PRP injections for treatment of grade 2 hamstring injuries may be advantageous in professional athletes.

Nonbiologic Injections in Sports Medicine

Nonbiologic medications (local anesthetics, corticosteroids, and nonsteroidal anti-inflammatory drugs) are commonly administered to athletes for analgesia after injury. However, the risks of nonbiologic injections often are overlooked simply because of their long-term market availability. A thorough understanding of the mechanism of action, the reported benefits, and the potential risks of nonbiologic medications is crucial prior to their use, especially in the treatment of young athletes. Sports medicine physicians and surgeons must be aware of the systemic and local effects of these medications to ensure an appropriate drug choice that minimizes side effects and avoids recently reported toxicity to myocytes, tenocytes, and chondrocytes.

Additional studies on triamcinolone acetonide use and misuse in sports: Elimination profile after intranasal and high-dose intramuscular administrations

Triamcinolone acetonide (TA) is a glucocorticoid (GC) widely used in sports medicine. GCs are prohibited in sports competitions by oral, intramuscular (IM), intravenous and rectal administrations, and they are allowed by other routes considered of local action such as intranasal administration (INT). We examined the urinary profiles of TA and its metabolites after INT and high-dose IM administrations. We also measured concentrations of TA and cortisol (CORT) in plasma following IM administration. TA was administered to healthy volunteers using INT route (220 μg/day for 3 days, n = 4 males and 4 females) or IM route (single dose of 40 mg, n = 4 males and 4 females and single dose 80 mg, n = 4 males). Urine and plasma samples were collected before and after administration at different time periods, and were analysed by liquid chromatography-tandem mass spectrometry. TA concentrations in urine were constant during 23 days after IM injection (range 1.4-129.0 ng/mL), and were very low after INT administration (range 0.0-3.5 ng/mL). For 6β-hydroxy-triamcinolone, the main TA metabolite, higher concentrations were detected (0.0-93.7 ng/mL and 15.7-973.9 ng/mL after INT and IM administrations, respectively). On the other hand, TA was detected in all plasma samples collected during 23 days after IM administration (range 0.2-5.7 ng/mL). CORT levels were largely suppressed after IM injection, and were recovered in a dose-dependent manner. In view of the results obtained, we propose a reporting level of 5 ng/mL for TA to distinguish forbidden from allowed TA administrations in sports. We also suggest that other GCs with faster urinary elimination from the body should be considered for IM therapies in out-of-competition rather than TA, in order to reduce the possibility of reporting false adverse analytical findings.

A Systematic Review of the Orthopaedic Literature Involving National Football League Players

Background

Orthopaedic injuries of National Football League (NFL) players can have a deleterious effect on their health, with minimal to no high-level evidence on the management of these injuries.

Purpose

To summarize all data published between January 1980 and March 2018 on orthopaedic injuries experienced by NFL candidates and professional players in the NFL.

Study Design

Systematic review; Level of evidence, 4.

Methods

A literature search of studies examining orthopaedic injuries in the NFL was performed through the PubMed, Embase, and CINAHL databases. The review included studies of orthopaedic injuries in college football recruits attending the NFL Combine as well as professional NFL players. Excluded were studies of nonorthopaedic injuries, such as concussions, traumatic brain injury, facial injuries, and vascular injuries, as well as case reports.

Results

A total of 147 articles met the inclusion criteria and were divided into 11 topics based on anatomic site: general (16%), spine (13%), shoulder (13%), elbow (3%), hand and wrist (3%), trunk (0.7%), hip and pelvis (7%), thigh (3%), knee (24%), ankle (5%), and foot (12%). Of these studies, 74% were of level 4 evidence. Most studies obtained data from the NFL Combine database (26%), by searching the internet (24%), and via the NFL Injury Surveillance System (22%). Studies using internet search methods to identify injuries consistently found fewer participants than studies using the NFL Injury Surveillance System.

Conclusion

This systematic review provides National Collegiate Athletic Association and NFL team physicians with a single source of the most current literature regarding orthopaedic injuries in NFL players. Most research was published on knee, spine, shoulder, and foot injuries and consisted of level 4 evidence. A substantial portion of the published literature was based on data obtained from internet searches and may not accurately represent the NFL population.

Development of Microfluidic Stretch System for Studying Recovery of Damaged Skeletal Muscle Cells

The skeletal muscle occupies about 40% mass of the human body and plays a significant role in the skeletal movement control. Skeletal muscle injury also occurs often and causes pain, discomfort, and functional impairment in daily living. Clinically, most studies observed the recovery phenomenon of muscle by massage or electrical stimulation, but there are limitations on quantitatively analyzing the effects on recovery. Although additional efforts have been made within in vitro biochemical research, some questions still remain for effects of the different cell microenvironment for recovery. To overcome these limitations, we have developed a microfluidic system to investigate appropriate conditions for repairing skeletal muscle injury. First, the muscle cells were cultured in the microfluidic chip and differentiated to muscle fibers. After differentiation, we treated hydrogen peroxide and 18% axial stretch to cause chemical and physical damage to the muscle fibers. Then the damaged muscle fibers were placed under the cyclic stretch condition to allow recovery. Finally, we analyzed the damage and recovery by quantifying morphological change as well as the intensity change of intracellular fluorescent signals and showed the skeletal muscle fibers recovered better in the cyclic stretched condition. In total, our in situ generation of muscle damage and induction recovery platform may be a key system for investigating muscle recovery and rehabilitation.

Magnetic resonance imaging of muscle injury in elite American football players: Predictors for return to play and performance

Muscle injury accounts for about one-third of total sports-related injuries. The lower limb muscles have one of the highest predisposition for injury in high-level professional athletic sports, such as the National Football League. The commonest group of muscles injured among football players include the hamstrings, followed by the quadriceps. Muscle injuries lead to significant time, off the field and affect return to play. Sports physicians and teams have been keen on assessing such injuries and also relying on multiple tools to safely return the player back to the field. MRI plays a key role in evaluation, follow-up, and assessment for return to play (RTP). In this review, we will discuss details of muscle anatomy, incidence of muscle injuries, injury mechanisms, and use of MRI in assessment, grading, follow-up and in predicting the natural course of muscle injuries in the high-end athletic players. While the use of MRI is clear in diagnosis, and for follow up of muscle injuries, there is some limitation in its ability to predict RTP, based on current MRI classification systems. Footballers who have clinical injuries without MRI evidence of significant muscle injury (grade 0 and 1) have a shorter period of RTP. Injuries classified as high grade (3 and 4) on MRI do not correlate well with time to RTP. Further trials are required to improve the capability of MRI in its prediction of RTP.

Injectable Corticosteroids in Sport

OBJECTIVE

To review the literature guiding all aspects of the use of injectable corticosteroids for painful musculoskeletal conditions, with a focus on the treatment of athletes.

DATA SOURCES

An extensive search of the literature was completed including search terms of corticosteroid, steroid, athlete, and injection, among others. Additional articles were used after being identified from previously reviewed articles.

MAIN RESULTS

Injections of corticosteroids for a variety of painful conditions of the extremities and the axial spine have been described. Numerous minor and major complications have been reported, including those with a high degree of morbidity. There is a dearth of published research on the use of corticosteroid injections in athletes, with most of the research on this topic focused on older, nonathlete populations. Generally, these injections are well tolerated and can provide short-term pain improvement with little or no long-term benefits.

CONCLUSIONS

Corticosteroid injections should be used cautiously in athletes and only after a full consideration of the pharmacology, pathogenesis of disease, potential benefits, complications, factors specific to the athlete, and rules of athletic governing bodies. Corticosteroid injections are just one component of a comprehensive rehabilitation plan available to the physician providing care to athletes.

Analgesic Management of Pain in Elite Athletes: A Systematic Review

OBJECTIVE

To identify the prevalence, frequency of use, and effects of analgesic pain management strategies used in elite athletes.

DESIGN

Systematic literature review.

DATA SOURCES

Six databases: Ovid/Medline, SPORTDiscus, CINAHL, Embase, Cochrane Library, and Scopus.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Empirical studies involving elite athletes and focused on the use or effects of medications used for pain or painful injury. Studies involving recreational sportspeople or those that undertake general exercise were excluded.

MAIN RESULTS

Of 70 articles found, the majority examined the frequency with which elite athletes use pain medications, including nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, anesthetics, and opioids. A smaller set of studies assessed the effect of medications on outcomes such as pain, function, and adverse effects. Oral NSAIDs are reported to be the most common medication, being used in some international sporting events by over 50% of athletes. Studies examining the effects of pain medications on elite athletes typically involved small samples and lacked control groups against which treated athletes were compared.

CONCLUSIONS

Existing empirical research does not provide a sufficient body of evidence to guide athletes and healthcare professionals in making analgesic medication treatment decisions. Based on the relatively robust evidence regarding the widespread use of NSAIDs, clinicians and policymakers should carefully assess their current recommendations for NSAID use and adhere to a more unified consensus-based strategy for multidisciplinary pain management in elite athletes. In the future, we hope to see more rigorous, prospective studies of various pain management strategies in elite athletes, thus enabling a shift from consensus-based recommendations to evidence-based recommendations.

Nonoperative treatment of muscle injuries - recommendations from the GOTS expert meeting

BACKGROUND

Muscle injuries are some of the most common injuries in sports; they have a high recurrence rate and can result in the loss of ability to participate in training or competition. In clinical practice, a wide variety of treatment strategies are commonly applied. However, a limited amount of evidence-based data exists, and most therapeutic approaches are solely based on "best practice". Thus, there is a need for consensus to provide strategies and recommendations for the treatment of muscle injuries.

METHODS

The 2016 GOTS Expert Meeting, initiated by the German-Austrian-Swiss Society for Orthopaedic Traumatologic Sports Medicine (GOTS), focused on the topic of muscle and tendon injuries and was held in Spreewald/Berlin, Germany. The committee was composed of twenty-two medical specialists. Nine of them were delegated to a subcommittee focusing on the nonoperative treatment of muscle injuries. The recommendations and statements that were developed were reviewed by the entire consensus committee and voted on by the members.

RESULTS

The committee reached a consensus on the utility and effectiveness of the management of muscle injuries.

MAIN RESULTS

the "PRICE" principle to target the first inflammatory response is one of the most relevant steps in the treatment of muscle injuries. Haematoma aspiration may be considered in the early stages after injury. There is presently no clear evidence that intramuscular injections are of use in the treatment of muscle injuries. The ingestion of non-steroidal anti-inflammatory drugs (NSAIDs) should be regarded critically because there is currently no hard evidence to support their use, although they are appropriate in exceptional cases.

CONCLUSIONS

The present work provides a structured overview of the various nonoperative treatment strategies of muscle injuries and evaluates their effectiveness with respect to the existing scientific evidence and clinical expertise in the context of basic science on the healing process of muscle injuries. The committee agreed that there is a compelling need for further studies, including high-quality randomized investigations to completely evaluate the effectiveness of the existing therapeutic approaches. The given recommendations may be updated and adjusted as further evidence will be generated.

Does Platelet-Rich Plasma Lead to Earlier Return to Sport When Compared With Conservative Treatment in Acute Muscle Injuries? A Systematic Review and Meta-analysis

PURPOSE

To compare the time to return to sport and reinjury rate after platelet-rich plasma (PRP) injection versus control therapy (i.e., physiotherapy or placebo injection) in patients with acute grade I or II muscle strains.

METHODS

All eligible studies comparing PRP against a control in the treatment of acute (≤7 days) grade I or II muscle strains were identified. The primary outcome was time to return to play. The secondary outcome was the rate of reinjury at a minimum of 6 months of follow-up. Subgroup analysis was performed to examine the efficacy of PRP in hamstring muscle strains alone. The checklist to evaluate a report of a nonpharmacologic trial (CLEAR-NPT) was used to assess the quality of studies.

RESULTS

Five randomized controlled trials including a total of 268 patients with grade I and II acute muscle injuries were eligible for review. The pooled results revealed a significantly earlier return to sport for the PRP group when compared with the control group (mean difference, -5.57 days [95% confidence interval, -9.57 to -1.58]; P = .006). Subgroup analysis showed no difference in time to return to sport when comparing PRP and control therapy in grade I and II hamstring muscle strains alone (P = .19). No significant difference was noted in the rate of reinjury between the 2 groups (P = .50) at a minimum of 6 months of follow-up.

CONCLUSIONS

Evidence from the current literature, although limited, suggests that the use of PRP may result in an earlier return to sport among patients with acute grade I or II muscle strains without significantly increasing the risk of reinjury at 6 months of follow-up. However, no difference in time to return to sport was revealed when specifically evaluating those with a grade I or II hamstring muscle strain.

LEVEL OF EVIDENCE

Level II, meta-analysis of level I and II studies.

Hamstring Injuries in the Athlete: Diagnosis, Treatment, and Return to Play

Hamstring injuries are very common in athletes. Acute hamstring strains can occur with high-speed running or with excessive hamstring lengthening. Athletes with proximal hamstring tendinopathy often do not report a specific inciting event; instead, they develop the pathology from chronic overuse. A thorough history and physical examination is important to determine the appropriate diagnosis and rule out other causes of posterior thigh pain. Conservative management of hamstring strains involves a rehabilitation protocol that gradually increases intensity and range of motion, and progresses to sport-specific and neuromuscular control exercises. Eccentric strengthening exercises are used for management of proximal hamstring tendinopathy. Studies investigating corticosteroid and platelet-rich plasma injections have mixed results. Magnetic resonance imaging and ultrasound are effective for identification of hamstring strains and tendinopathy but have not demonstrated correlation with return to play. The article focuses on diagnosis, treatment, and return-to-play considerations for acute hamstring strains and proximal hamstring tendinopathy in the athlete.

Acute Gastrocnemius-Soleus Complex Injuries in National Football League Athletes

BACKGROUND

Lower extremity muscle injuries are common in professional football. Although less common than hamstring or quadriceps injuries in National Football League (NFL) athletes, calf injuries occur with relative frequency and have not previously been studied.

PURPOSE

To evaluate gastrocnemius-soleus complex muscle injuries over the past 13 years from a single NFL team to determine the incidence of such injuries, their imaging characteristics, and return to play after such injuries and any correlation between imaging findings and prolonged return to play.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A retrospective review of all acute calf muscle injuries on a single NFL team from 2003 to 2015 was performed. Player demographics and return-to-play data were obtained from the medical records. All available magnetic resonance images (MRIs) were reviewed by a musculoskeletal radiologist for specific imaging findings that correlated with return to play.

RESULTS

A total of 27 calf injuries in 24 NFL players were reviewed, yielding an incidence of 2.3 acute calf injuries per year on a single NFL team. Of these 27 injuries, 20 (74%) were isolated injuries to the gastrocnemius muscle, 4 (15%) were isolated injuries to the soleus muscle, and the remaining 3 injuries (11%) involved both. Defensive players were more likely to sustain injuries (P = .043). The mean time to return to play for all 27 players was 17.4 ± 14.6 days (range, 3-62 days). MRIs were available in 14 of the 27 injuries. The average size of the fascial defect (P = .032) and the presence of a fluid collection (P = .031) both correlated with return to play of longer than 2 weeks.

CONCLUSION

Although less common than hamstring or quadriceps muscle injuries, calf muscle injuries occur with relative frequency in the NFL, and more so in defensive players. The majority of these injuries occur in the gastrocnemius and result in significant disability, with at least 2 weeks of missed playing time on average. MRI may have an important role in the evaluation of calf injuries in NFL players, as certain injury imaging characteristics, including the anteroposterior size of any fascial tear and the presence of a fluid collection, are associated with longer return-to-play times after injury.

Surgical Management of Recurrent Musculotendinous Hamstring Injury in Professional Athletes

BACKGROUND

Hamstring injury is the most common muscular lesion in athletes. The conservative treatment is well described, and surgical management is often indicated for proximal tendinous avulsions. To our knowledge, no surgical treatment has been proposed for failure of conservative treatment in musculotendinous hamstring lesions.

PURPOSE

To describe the surgical management of proximal and distal hamstring musculotendinous junction lesions in professional athletes after failure of conservative treatment.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A consecutive series of 10 professional athletes, including 4 soccer players, 4 rugby players, and 2 handball players, underwent surgical intervention between October 2010 and June 2014 for the treatment of recurrent musculotendinous hamstring injuries. All athletes had failed at least 3 months of conservative treatment for a recurrent musculotendinous hamstring injury. Surgical resection of the musculotendinous scar tissue was performed using a longitudinal muscular suture. Lower Extremity Functional Scale (LEFS) and Marx scores were obtained at the 3-month follow-up, and a final phone interview was completed to determine recurrence of hamstring injury and return to previous level of play.

RESULTS

The mean age at surgery was 25.2 years (range, 19-35 years). The musculotendinous hamstring lesions involved 8 semitendinosus and 2 biceps femoris, with 6 injuries located proximally and 4 distally. Conservative treatment lasted a mean 5.1 months (range, 3-9 months) after last recurrence, and the patients had an average of 2.7 (range, 2-5) separate incidents of injury recurrence before surgical intervention was decided upon. At the 3-month follow-up, all patients had Marx activity scores of 16 and LEFS scores of 80. All 10 patients returned to the same level of play at a mean 3.4 months (range, 2-5 months). At a mean follow-up of 28.7 months, none of the athletes had suffered a recurrence. No surgical complication was encountered.

CONCLUSION

In cases of failed conservative treatment of musculotendinous hamstring lesions, surgical intervention may be a viable treatment option in professional athletes and allows the patient to return to the same level of play.

Perspectives in ultrasound-guided musculoskeletal interventions

Ultrasonography (USG) is a safe, easily available, and cost-effective modality, which has the additional advantage of being real time for imaging and image-guided interventions of the musculoskeletal system. Musculoskeletal interventions are gaining popularity in sports and rehabilitation for rapid healing of muscle and tendon injuries in professional athletes, healing of chronic tendinopathies, aspiration of joint effusions, periarticular bursae and ganglia, and perineural injections in acute and chronic pain syndromes. This article aims to provide an overview of the spectrum of musculoskeletal interventions that can be done under USG guidance both for diagnostic and therapeutic purposes.

Clinical principles in the management of hamstring injuries

PURPOSE

Hamstring injuries are among the most common muscle injuries seen in sports clinical practice. This narrative review covers essential knowledge of hamstring injuries, ranging from strains to total proximal three-tendon ruptures. The primary aim is to provide basic information for clinicians and sports medicine therapists dealing with hamstring problems.

METHODS

In this review, existing literature of hamstring injuries was taken together. Emphasis was given to subjects less well covered in previous reviews, such as preventive measures, as well as the most relevant information needed in the treatment of these injuries.

RESULTS

Occasionally, symptoms remain after hamstring injuries which can be successfully treated with surgery. Knowledge of the effectiveness of preventive measures and nonsurgical and surgical treatment is limited by small studies of low evidence level.

CONCLUSIONS

Evidence-based treatment algorithms are not available. Larger studies of better quality with more concrete grading of hamstring tears are needed to improve knowledge in prevention and treatment of hamstring injuries.

LEVEL OF EVIDENCE

IV.

Return to sport after muscle injury

Skeletal muscle injuries are among the most common sports-related injuries that result in time lost from practice and competition. The cellular response to muscle injury can often result in changes made to the muscle fibers as well as the surrounding extracellular matrix during repair. This can negatively affect the force and range of the injured muscle even after the patient's return to play. Diagnosis of skeletal muscle injury involves both history and physical examinations; imaging modalities including ultrasound and magnetic resonance imaging (MRI) can also be used to assess the extent of injury. Current research is investigating potential methods, including clinical factors and MRI, by which to predict a patient's return to sports. Overall, function of acutely injured muscles seems to improve with time. Current treatment methods for skeletal muscle injuries include injections of steroids, anesthetics, and platelet-rich plasma (PRP). Other proposed methods involve inhibitors of key players in fibrotic pathways, such as transforming growth factor (TGF)-ß and angiotensin II, as well as muscle-derived stem cells.

Cytotoxic effects of ropivacaine, bupivacaine, and lidocaine on rotator cuff tenofibroblasts

BACKGROUND

Concern has recently arisen over the safety of local anesthetics used on human tissues.

HYPOTHESIS

Aminoamide local anesthetics have cytotoxic effects on human rotator cuff tenofibroblasts.

STUDY DESIGN

Controlled laboratory study.

METHODS

Cultured human rotator cuff tenofibroblasts were divided into control, phosphate buffered saline (PBS), and local anesthetic study groups; the PBS study group was further subdivided by pH level (pH 7.4, 6.0, and 4.4). The 6 local anesthetic subgroups (0.2% and 0.75% ropivacaine, 0.25% and 0.5% bupivacaine, and 1% and 2% lidocaine) were also studied at 10% dilutions of their original concentrations. Exposure times were 5, 10, 20, 40, or 60 minutes for the higher concentrations and 2, 6, 12, 24, 48, or 72 hours for the lower concentrations. Cell viability was evaluated through live, apoptotic, and necrotic cell rates using the annexin V-propidium iodide double-staining method. Intracellular reactive oxygen species (ROS) and the activity of mitogen-activated protein kinases (MAPKs) and caspase-3/7 were investigated.

RESULTS

The control and PBS groups showed no significant differences in cell viability (P > .999). In the local anesthetic study groups, cell viability decreased significantly with increases in anesthetic concentrations (P < .001) and exposure times (P < .001), with the exception of the lidocaine subgroups, where this effect was masked by the very high cytotoxicity of even low concentrations. Among the studied local anesthetic subgroups, 0.2% ropivacaine was the least toxic. The levels of intracellular ROS of each local anesthetic subgroup also increased significantly (P < .05). The studied local anesthetics showed increases in the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38 as well as in levels of caspase-3/7 activity (P < .001).

CONCLUSION

The cytotoxicity of the anesthetics studied to tenofibroblasts is dependent on exposure time and concentration. Of the evaluated anesthetics, ropivacaine is the least toxic in the clinically used concentration. The studied anesthetics induce tenofibroblast cell death, mediated by the increased production of ROS, by the increased activation of ERK1/2, JNK, and p38 and by the activation of caspase-3/7.

CLINICAL RELEVANCE

This study identified the cytotoxic mechanisms of aminoamide local anesthetics acting on rotator cuff tenofibroblasts. The greatest margin of safety was found in lower anesthetic concentrations in general and more specifically in the use of ropivacaine.

Corticosteroid and Anesthetic Injections for Muscle Strains and Ligament Sprains in the NFL

BACKGROUND

Administering local anesthetic or corticosteroid injections in professional athletes to allow return to play is common but has traditionally been viewed as suspect and taboo. The skepticism surrounding therapeutic injections stems predominantly from anecdotal experience as opposed to scientific data.

QUESTIONS/PURPOSES

The purpose of this paper is to evaluate the current use of corticosteroid injections for muscle strains and ligaments sprains in the National Football League to document player's ability to return to play and possible adverse effects.

PATIENTS AND METHODS

Athletes from a single National Football League team who received at least one corticosteroid or anesthetic injection for either a muscle strain or ligament sprain during three consecutive seasons were retrospectively reviewed. Thirty-seven injections were given over the three seasons. Injections were either performed blindly or by using ultrasound guidance.

RESULTS

Twice as many defensive players were injected than offensive players. The average number of days of conservative treatment before injection was 6.5 days. All players returned to play after injection. There were no complications from any of the injections. Seventeen (55%) players did not miss a single game, and nine (30%) did not miss a single day. Quadriceps strains were associated with the most missed games (four) and the most missed days (36.5). Proximal hamstring strains were second with an average of three missed games and 28 missed days.

CONCLUSION

Corticosteroid injections are a safe and effective therapeutic intervention for treating muscle strains and ligament sprains in order to enable athletes to return to competition earlier.

Muscle injuries in athletes: enhancing recovery through scientific understanding and novel therapies

Context:

Muscle injuries are extremely common in athletes and often produce pain, dysfunction, and the inability to return to practice or competition. Appropriate diagnosis and management can optimize recovery and minimize time to return to play.

Evidence Acquisition:

Contemporary papers, both basic science and clinical medicine, that investigate muscle healing were reviewed. A Medline/PubMed search inclusive of years 1948 to 2012 was performed.

Results:

Diagnosis can usually be made according to history and physical examination for most injuries. Although data are limited, initial conservative management emphasizing the RICE principles and immobilization of the extremity for several days for higher grade injuries are typically all that is required. Injection of corticosteroids may clinically enhance function after an acute muscle strain. Additional adjunctive treatments (nonsteroidal anti-inflammatory drugs, platelet-rich plasma, and others) to enhance muscle healing and limit scar formation show promise but need additional data to better define their roles.

Conclusion:

Conservative treatment recommendations will typically lead to successful outcomes after a muscle injury. There is limited evidence to support most adjunctive treatments.

Medical interventions in the management of hamstring muscle injury

Acute muscle belly injuries to the semitendinosus, semimembranosus and biceps femoris (the 'hamstring' muscles) remain a common problem in the sporting population. Physiotherapy-led rehabilitation remains the mainstay of treatment, and the physician's input is often minimal. Anecdotally, many different topical, oral and injectable therapies are used around the world in an effort to accelerate the healing of these injuries and to prevent their recurrence. This article reviews the evidence available to support some of the most commonly used medical therapies and the pathophysiological basis for their use. It also presents the evidence behind some of the more promising future treatments for muscle injury, including stem cell therapy, growth factor delivery and potential novel uses of current medication not traditionally used in the musculoskeletal setting.

Evaluation and management of hamstring injuries

Muscle injuries are the most common injuries in sports, with hamstring injuries accounting for 29% of all injuries in athletes. These injuries lead to prolonged impairment and have a reinjury risk of 12% to 31%. They range from mild muscle damage without loss of structural integrity to complete muscle tearing with fiber disruption. Novel MRI scores are increasingly being used and allow a more precise prediction of return to sport. In this article, the authors review the history, mechanisms of injury, and classification systems for hamstring injuries as well as present the latest evidence related to the management of hamstring injuries, including intramuscular and both proximal and distal insertional injuries. Indications for surgical treatment of certain proximal and distal avulsions, biological augmentation to the nonoperative treatment of midsubstance injuries, and advances in risk reduction and injury prevention are discussed.

Platelet-rich plasma as an effective treatment for proximal hamstring injuries

Proximal hamstring injuries can be disabling, and several traditional conservative treatments, including physiotherapy and nonsteroidal anti-inflammatory drugs, have been inconsistent. Corticosteroid injections have demonstrated success but can adversely affect local tissues. Platelet-rich plasma (PRP) has emerged as a safe, effective treatment for several orthopedic pathologies. The authors propose a PRP injection at the muscle origin as a novel treatment for proximal hamstring injuries. A retrospective review yielded 15 patients with 17 proximal hamstring injuries. Twelve injuries failed traditional conservative treatment and were ultimately treated with a PRP injection at the hamstrings muscle origin. Five patients were treated with traditional conservative treatment alone. Analysis included pre- and posttreatment visual analog scale scores, Nirschl Phase Rating Scale scores, and return to sport. No significant difference existed between the groups' pretreatment visual analog scale scores (P=.28) and Nirschl Phase Rating Scale scores (P=.15) and their posttreatment visual analog scale scores (P=.38) and Nirschl Phase Rating Scale scores (P=.22). The PRP group demonstrated a reduction in visual analog scale scores (P<.01) and Nirschl Phase Rating Scale scores (P<.01), but the traditional conservative treatment group did not demonstrate the same reduction (P=.06 and .06, respectively). All athletes returned to their desired activity level with no major complications.

Rehabilitation for hamstring injuries

BACKGROUND

Hamstring injuries are a common musculoskeletal disorder, particularly amongst athletes. Many factors have been associated with these injuries, including motor control and strength, soft tissue length and postural alignment. Well-established rehabilitation protocols are commonly used in the treatment of this condition, but their effectiveness remains questionable. This is an update of a Cochrane review first published in 2007.

OBJECTIVES

To evaluate the effectiveness of all rehabilitation strategies employed to promote the return to full strength, range of movement and function of those individuals presenting with all forms of hamstring injury, regardless of site, severity, onset or level of chronicity.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (to September 2011), the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2011 Issue 3), MEDLINE (including in-process & other non-indexed citations: 1966 to August 2011), EMBASE (1980 to September 2011), PEDro (2006 to June 2012), CINAHL (1937 to September 2011), AMED (1985 to September 2011), SPORTDiscus (1859 to February 2006), and the World Health Organisation International Clinical Trials Registry platform (April 2012).

SELECTION CRITERIA

Randomised clinical trials investigating the effect of at least one rehabilitation strategy, in isolation or combination with another, compared with another strategy or control, performed on individuals presenting with hamstring injuries.

DATA COLLECTION AND ANALYSIS

Two review authors performed study selection. All review authors performed data extraction and assessed risk of bias. Any disagreement was resolved by discussion.

MAIN RESULTS

Two trials were included in the review, totaling 104 participants. One trial assessed additional (four times a day) versus once daily stretching and the other assessed exercise for movement dysfunction versus stretching and strengthening. The first trial, involving 80 elite athletes, suggested additional stretching could reduce time to return to full activity (mean difference (MD) -1.8 days, 95% confidence interval (CI) -2.1 to -1.5, P < 0.001). The second trial, involving 24 participants from a diverse sporting background, did not find conclusive evidence of a difference (MD -14.5 days, 95% CI -30.64 to 1.64, P = 0.08). It did, however, report reduced re-injury rates using exercise for movement dysfunction of 8% versus 64% (odds ratio (OR) 0.05, 95% CI 0.00 to 0.52, P = 0.01). No other outcomes relevant to this review were reported by either study: most notably pain and participant satisfaction.

AUTHORS' CONCLUSIONS

Most proposed physiotherapy techniques for rehabilitation of hamstring injuries have not been assessed using randomised trials. Those that have only have single studies with a limited range of participants and outcomes. There is limited evidence to suggest that time to recovery for elite athletes can be reduced with an increased daily frequency of hamstring stretching exercises. There is preliminary evidence from another small study of mixed ability athletes to suggest that exercise to correct movement dysfunction could reduce time to return to full activity and the risk of re-injury. Further studies are required to check these findings. Until further evidence is available, current practice and widely published rehabilitation protocols cannot either be supported or refuted.

An evidence-based approach to hamstring strain injury: a systematic review of the literature

Background:

Hamstring strain injury is a common problem within sport. Despite research interest, knowledge of risks for and management of hamstring strain is limited, as evidenced by high injury rates.

Objective:

To present the current best evidence for hamstring strain injury risk factors and the management of hamstring strain injury.

Methods:

MEDLINE, AMED, SportDiscus, and AUSPORT databases were searched (key terms “hamstring” and “strain,” “injury,” “pull,” or “tear”) to identify relevant literature published between 1982 and 2007 in the English language. Studies of adult athlete populations (older than 18 years) pertaining to hamstring strain incidence, prevalence, and/or intervening management of hamstring strain injury were included. Articles were limited to full-text randomized, controlled studies or cohort studies. Twenty-four articles were included. Articles were critically appraised using the McMaster Quantitative Review Guidelines instrument. Data pertaining to injury rates and return to sport outcomes were extracted. Each author undertook independent appraisal of a random selection of articles after establishing inter-rater agreement of appraisal.

Results:

Previous strain, older age, and ethnicity were consistently reported as significant risks for injury, as was competing in higher levels of competition. Associations with strength and flexibility were conflicting. Functional rehabilitation interventions had preventive effects and resulted in significantly earlier return to sport. Additionally, weak evidence existed for other interventions.

Conclusion:

Current evidence is inconclusive regarding most interventions for hamstring strain injury, while the effect of potentially modifiable risks is unclear. Further high-quality prospective studies into potential risks and management are required to provide a better framework within which to target interventions.

Rehabilitation of running injuries

Rehabilitating the injured runner involves a thorough evaluation of the runner. The running history is at least as critical as the physical examination to determine the risk factors for injury and goals for rehabilitation. The medical assessment should include an office situation in which the runner can be seen walking and running to ensure that the rehabilitation program is complete and successful.

High hamstring tendinopathy: MRI and ultrasound imaging and therapeutic efficacy of percutaneous corticosteroid injection

OBJECTIVE

The goals of this study were to review the MRI and sonographic findings in patients diagnosed clinically with high hamstring tendinopathy and to evaluate the efficacy of ultrasound-guided corticosteroid injections in providing symptomatic relief.

CONCLUSION

MRI is more sensitive than ultrasound in detecting peritendinous edema and tendinopathy at the proximal hamstring origin. Fifty percent of patients had symptomatic improvement lasting longer than 1 month after percutaneous corticosteroid injection, and 24% of patients had symptom relief for more than 6 months.

Doping and musculoskeletal system: short-term and long-lasting effects of doping agents

Doping is a problem that has plagued the world of competition and sports for ages. Even before the dawn of Olympic history in ancient Greece, competitors have looked for artificial means to improve athletic performance. Since ancient times, athletes have attempted to gain an unfair competitive advantage through the use of doping substances. A Prohibited List of doping substances and methods banned in sports is published yearly by the World Anti-Doping Agency. Among the substances included are steroidal and peptide hormones and their modulators, stimulants, glucocorticosteroids, β₂-agonists, diuretics and masking agents, narcotics, and cannabinoids. Blood doping, tampering, infusions, and gene doping are examples of prohibited methods indicated on the List. Apart from the unethical aspect of doping, as it abrogates fair-play's principle, it is extremely important to consider the hazards it presents to the health and well-being of athletes. The referred negative effects for the athlete's health have to do, on the one hand, by the high doses of the performance-enhancing agents and on the other hand, by the relentless, superhuman strict training that the elite or amateur athletes put their muscles, bones, and joints. The purpose of this article is to highlight the early and the long-lasting consequences of the doping abuse on bone and muscle metabolism.

The natural history and management of hamstring injuries

Hamstring injuries in sport can be debilitating. The anatomical complexity of this muscle makes uniform assessment of injury epidemiology difficult and insures that post-injury management strategies must be individually focused. This article reviews the anatomy of the hamstring, its role in athletic movement, common mechanisms of injury, and management guidelines with the goal of return into sporting activity in mind.