Rehabilitation for hamstring injuries

Clinical Progression and Load Management For Proximal Hamstring Tendinopathy In A Long-Distance Runner: A Case Report

Background and Purpose

The characteristics of Proximal Hamstring Tendinopathy (PHT) include deep, localized pain in the region of the ischial tuberosity. Chronic lesions are often found in long-distance runners. Compression of the tendon and shear force at its insertion at the ischial tuberosity during hip flexion/adduction is a key etiologic factor. The aim of this case report is to analyze the effectiveness of an exercise protocol with progression of tendon loading in PHT in an amateur runner, by assessing pain and functional capacity.

Case Description

The subject was a 30-year-old male runner. After participating in a 10km race, he experienced an insidious onset of deep buttock pain in the right ischial tuberosity. His pain was aggravated by running on sloped roads and prolonged sitting on hard surfaces, particularly while driving. The visual analog scale (VAS) for pain, the Puranen-Orave test (PO), the Bent-Knee stretch test (BK stretch), the supine plank test, the Victorian Institute of Sport Assessment-proximal hamstring tendons (VISA-H) questionnaire, and the sciatic nerve mobility (via the Slump test) were assessed. The intervention involved a 12-week progressive loading exercise program divided into four phases.

Outcomes

The initial pain was reduced at 6 weeks of intervention and further decreased at 12 weeks (VAS from 7, to 5 and to 1). Function increased at 6 weeks and at 12 weeks (VISA-H from 23, to 53, to 80). Sciatic nerve mobility was normal.

Conclusion

The progression of training in a subject with PHT tendon injury based on isometric exercise, concentric/eccentric, energy storage, progressively increasing hip flexion was beneficial, increasing function and decreasing pain. Studies with a larger sample size and a more precise methodological design would be necessary to support this type of intervention in clinical practice.

Level of Evidence

5.

Do athletes with hamstring strain injury have shorter muscle fascicles in the injured limb?

INTRODUCTION

Previous studies have suggested that a reduced length of the biceps femoris long head (BFlh) fascicles may increase the risk of hamstring strain injury (HSI). However, it remains unclear whether the BFlh fascicles of the injured limb are shorter than those of the contralateral limb in athletes with an acute HSI.

OBJECTIVE

To investigate the between-limb asymmetry of BFlh fascicle length in amateur athletes with an acute HSI.

METHODS

Male amateur athletes were evaluated using ultrasound scans within five days following an HSI. The BFlh fascicle length was estimated using a validated equation.

RESULTS

Eighteen injured athletes participated in this study. There was no significant difference (p = 0.27) in the length of BFlh fascicles between the injured limb (9.53 ± 2.55 cm; 95%CI 8.26 to 10.80 cm) and the uninjured limb (10.54 ± 2.87 cm; 95%CI 9.11 to 11.97 cm). Individual analysis revealed high heterogeneity, with between-limb asymmetries (percentage difference of the injured limb compared to the uninjured limb) ranging from -42% to 25%. Nine out of the 18 athletes had a fascicle length that was more than 10% shorter in the injured limb compared to the uninjured limb, five athletes had a difference of less than 10%, and four athletes had a fascicle length that was more than 10% longer in the injured limb compared to the uninjured limb.

CONCLUSION

The architecture characteristics of injured and uninjured muscles is not consistent among athletes with HSI. Therefore, rehabilitation programs focused on fascicle lengthening should be evaluated on a case-by-case basis.

Differences in shear elastic modulus of the latissimus dorsi muscle during stretching among varied trunk positions

The latissimus dorsi (LD) can be divided into the upper, middle, and lower parts, but the effective stretching positions for each part are unknown. In this study, we aimed to investigate effective trunk positions for stretching of the LD. A total of 14 healthy males participated in this study. The following seven trunk positions were chosen as the LD stretching positions; upright of the trunk (Baseline), flexion of the trunk (Flex), contralateral bending of the trunk (LB), contralateral rotation of the trunk (Rot), flexion and contralateral bending of the trunk (Flex + LB), flexion and contralateral rotation of the trunk (Flex + Rot), and contralateral bending and contralateral rotation of the trunk (LB + Rot). Maximal elevation of the upper limb was passively added to all positions. The shear elastic modulus, used as the index of muscle elongation, was measured at the four parts (upper, middle, lower, distal parts) of the LD. The shear elastic moduli showed obviously high values in Rot and LB + Rot at the upper, middle, and distal parts, and also in LB, Rot, and LB + Rot at the lower part. These findings suggest that contralateral trunk rotation, or a combination of contralateral trunk bending and rotation are effective trunk positions for stretching all parts of the LD. Contralateral trunk bending was also effective for stretching the lower part of the LD.

Platelet-Rich Plasma Injection for the Treatment of Hamstring Injuries: A Systematic Review and Meta-analysis With Best-Worst Case Analysis

BACKGROUND

Hamstring injuries are common and account for considerable time lost to play in athletes. Platelet-rich plasma has potential as a means to accelerate healing of these injuries.

PURPOSE

(1) To present the evidence of platelet-rich plasma injection in the treatment of hamstring injuries, (2) evaluate the "best-case scenario" in dichotomous outcomes, and (3) evaluate the "worst-case scenario" in dichotomous outcomes.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

Two authors systematically reviewed the PubMed, Embase, and Cochrane Library databases according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, with any discrepancies resolved by mutual consensus. The level of evidence was assessed per the criteria of the Oxford Centre for Evidence-Based Medicine and the quality of evidence by the Coleman Methodology Score. Meta-analysis by fixed effects models was used if heterogeneity was low (I² < 25%) and random effects models if heterogeneity was moderate to high (I²≥ 25%). P values <.05 were considered statistically significant.

RESULTS

A total of 10 studies were included with 207 hamstring injuries in the platelet-rich plasma group and 149 in the control group. Random-effects model for mean time to return to play that compared platelet-rich plasma + physical therapy to physical therapy alone non-significantly favored platelet-rich plasma + physical therapy (mean difference, -5.67 days). The fixed effects model for reinjury rates, which also compared platelet-rich plasma + physical therapy with physical therapy alone nonsignificantly favored platelet-rich plasma + physical therapy (risk ratio, 0.88). The best-case scenario fixed effects model for reinjury rates nonsignificantly favored platelet-rich plasma + physical therapy (risk ratio, 0.82). The worst-case scenario fixed effects model for reinjury rates nonsignificantly favored physical therapy alone (risk ratio, 1.13). The mean ± SD complication rate for either postinjection discomfort, pain, or sciatic nerve irritation was 5.2% ± 2.9% (range, 2.7% to 9.1%).

CONCLUSION

There has been statistically nonsignificant evidence to suggest that PRP injection ± PT reduced mean time to RTP or reinjury rates compared to no treatment or PT alone for hamstring injuries in a short-term follow-up. The complication profiles were favorable. Further studies of high quality and large cohorts are needed to better support or disprove the consensus of the systematic review and meta-analysis.

Effects of low-level laser therapy on hamstring strain injury rehabilitation: A randomized controlled trial

OBJECTIVES

To evaluate the effects of low-level laser therapy (LLLT) on functional rehabilitation following hamstring strain injury (HSI) in amateur athletes treated with an exercise-based rehabilitation program.

DESIGN

Randomized controlled trial.

METHODS

Male athletes (18-40 years old) who sustained HSI were randomized in LLLT or placebo groups. All patients were engaged in the same exercise-based rehabilitation program until they met specific criteria to return to sport. Hamstring muscles were treated with LLLT or placebo immediately after each rehabilitation session. The primary outcome was time-to-return to sport. Secondary outcomes were the number of rehabilitation sessions, hamstring flexibility, hamstring strength, and re-injury rate.

RESULTS

Twenty-four athletes began rehabilitation, and 22 (11 per group) completed the study schedule. Participants of LLLT and placebo groups had similar age, body size, injury characteristics, and baseline levels of hamstring flexibility and strength. The two groups increased flexibility and strength similarly throughout the rehabilitation program. Time-to-return to sport was the same for athletes treated with LLLT (23 ± 9 days) and placebo (24 ± 13 days). There were no re-injuries within 6 months after return to sport.

CONCLUSION

LLLT, as used in this study, did not optimize functional rehabilitation following HSI in amateur athletes treated with an exercise-based rehabilitation program.

The Construction of Sham Dry Needles and Their Validity

Appropriate control interventions are necessary to show the treatment effect of dry needling. Different control procedures, such as dry needling of the contralateral side, and sham treatments, such as random and superficial needle insertion, have been utilized in trials. However, those methods might elicit a physiological response and are subsequently not ideal for use as a control. This descriptive study illustrates the construction of low-cost sham dry needles and evaluates their validity. Forty-two healthy asymptomatic subjects received either sham or real dry needling intervention to their right gluteal muscles and reported if they felt that the needle pierced the skin. They also graded the severity and qualified (sharp or dull) the pain associated with the intervention. The results showed that most of the subjects in both groups believed the needle penetrated the skin. The quantity of pain associated with the treatment was similar in both groups, but the quality assigned was different. The authors conclude that sham dry needling can be accomplished and used as a valid control treatment in dry needling research using these low-cost sham needles.

Recurrent hamstring muscle injury: applying the limited evidence in the professional football setting with a seven-point programme

Recurrent hamstring injuries are a major problem in sports such as football. The aim of this paper was to use a clinical example to describe a treatment strategy for the management of recurrent hamstring injuries and examine the evidence for each intervention. A professional footballer sustained five hamstring injuries in a relatively short period of time. The injury was managed successfully with a seven-point programme—biomechanical assessment and correction, neurodynamics, core stability, eccentric strengthening, an overload running programme, injection therapies and stretching/relaxation. The evidence for each of these treatment options is reviewed. It is impossible to be definite about which aspects of the programme contributed to a successful outcome. Only limited evidence is available in most cases; therefore, decisions regarding the use of different treatment modalities must be made by using a combination of clinical experience and research evidence.

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.

Shockwave therapy for the treatment of chronic proximal hamstring tendinopathy in professional athletes

BACKGROUND

Chronic proximal hamstring tendinopathy is an overuse syndrome that is usually managed by nonoperative methods. Shockwave therapy has proved to be effective in many tendinopathies.

HYPOTHESIS

Shockwave therapy may be more effective than other nonoperative treatments for chronic proximal hamstring tendinopathy.

STUDY DESIGN

Randomized controlled clinical study; Level of evidence, 1.

METHODS

Forty professional athletes with chronic proximal hamstring tendinopathy were enrolled between February 1, 2004, and September 30, 2006. Patients were randomly assigned to receive either shockwave therapy, consisting of 2500 impulses per session at a 0.18 mJ/mm² energy flux density without anesthesia, for 4 weeks (SWT group, n = 20), or traditional conservative treatment consisting of nonsteroidal anti-inflammatory drugs, physiotherapy, and an exercise program for hamstring muscles (TCT group, n = 20). Patients were evaluated before treatment, and 1 week and 3, 6, and 12 months after the end of treatment. The visual analog scale (VAS) score for pain and Nirschl phase rating scale (NPRS) were used as primary outcome measures.

RESULTS

The patients were observed for a mean of 10.7 months (range, 1-12 months). Six patients were lost to follow-up because they underwent a surgical intervention: 3 (all in TCT group) were lost at 3 months; 2 (1 in each group), at 6 months; and 1 (in the TCT group), at 12 months. Primary follow-up was at 3 months after the beginning of treatment. The VAS scores in the SWT and TCT groups were 7 points before treatment (P = .84), and 2 points and 5 points, respectively, 3 months after treatment (P < .001). The NPRS scores in the SWT and TCT groups were 5 points in either group before treatment (P = .48), and 2 points and 6 points, respectively, 3 months after treatment (P < .001). At 3 months after treatment, 17 of the 20 patients (85%) in the SWT group and 2 of the 20 patients (10%) in the TCT group achieved a reduction of at least 50% in pain (P < .001). There were no serious complications in the SWT group.

CONCLUSION

Shockwave therapy is a safe and effective treatment for patients with chronic proximal hamstring tendinopathy.

A return-to-sport algorithm for acute hamstring injuries

Acute hamstring injuries are the most prevalent muscle injuries reported in sport. Despite a thorough and concentrated effort to prevent and rehabilitate hamstring injuries, injury occurrence and re-injury rates have not improved over the past 28 years. This failure is most likely due to the following: 1) an over-reliance on treating the symptoms of injury, such as subjective measures of "pain", with drugs and interventions; 2) the risk factors investigated for hamstring injuries have not been related to the actual movements that cause hamstring injuries i.e. not functional; and, 3) a multi-factorial approach to assessment and treatment has not been utilized. The purpose of this clinical commentary is to introduce a model for progression through a return-to-sport rehabilitation following an acute hamstring injury. This model is developed from objective and quantifiable tests (i.e. clinical and functional tests) that are structured into a step-by-step algorithm. In addition, each step in the algorithm includes a treatment protocol. These protocols are meant to help the athlete to improve through each phase safely so that they can achieve the desired goals and progress through the algorithm and back to their chosen sport. We hope that this algorithm can serve as a foundation for future evidence based research and aid in the development of new objective and quantifiable testing methods.

A descriptive study of a manual therapy intervention within a randomised controlled trial for hamstring and lower limb injury prevention

Background

There is little literature describing the use of manual therapy performed on athletes. It was our purpose to document the usage of a sports chiropractic manual therapy intervention within a RCT by identifying the type, amount, frequency, location and reason for treatment provided. This information is useful for the uptake of the intervention into clinical settings and to allow clinicians to better understand a role that sports chiropractors offer.

Methods

All treatment rendered to 29 semi-elite Australian Rules footballers in the sports chiropractic intervention group of an 8 month RCT investigating hamstring and lower-limb injury prevention was recorded. Treatment was pragmatically and individually determined and could consist of high-velocity, low-amplitude (HVLA) manipulation, mobilization and/or supporting soft tissue therapies. Descriptive statistics recorded the treatment rendered for symptomatic or asymptomatic benefit, delivered to joint or soft tissue structures and categorized into body regions. For the joint therapy, it was recorded whether treatment consisted of HVLA manipulation, HVLA manipulation and mobilization, or mobilization only. Breakdown of the HVLA technique was performed.

Results

A total of 487 treatments were provided (mean 16.8 consultations/player) with 64% of treatment for asymptomatic benefit (73% joint therapies, 57% soft tissue therapies). Treatment was delivered to approximately 4 soft tissue and 4 joint regions each consultation. The most common asymptomatic regions treated with joint therapies were thoracic (22%), knee (20%), hip (19%), sacroiliac joint (13%) and lumbar (11%). For soft tissue therapies it was gluteal (22%), hip flexor (14%), knee (12%) and lumbar (11%). The most common symptomatic regions treated with joint therapies were lumbar (25%), thoracic (15%) and hip (14%). For soft tissue therapies it was gluteal (22%), lumbar (15%) and posterior thigh (8%). Of the joint therapy, 56% was HVLA manipulation only, 36% high-HVLA and mobilization and 9% mobilization only. Of the HVLA manipulation, 63% was manually performed and 37% mechanically assisted.

Conclusions

The intervention applied was multimodal and multi-regional. Most treatment was for asymptomatic benefit, particularly for joint based therapies, which consisted largely of HVLA manipulation techniques. Most treatment was applied to non-local hamstring structures, in particular the knee, hip, pelvis and spine.

Posterior knee pain

Posterior knee pain is a common patient complaint. There are broad differential diagnoses of posterior knee pain ranging from common causes such as injury to the musculotendinous structures to less common causes such as osteochondroma. A precise understanding of knee anatomy, the physical examination, and of the differential diagnosis is needed to accurately evaluate and treat posterior knee pain. This article provides a review of the anatomy and important aspects of the history and physical examination when evaluating posterior knee pain. It concludes by discussing the causes and management of posterior knee pain.

The effect of a sports chiropractic manual therapy intervention on the prevention of back pain, hamstring and lower limb injuries in semi-elite Australian Rules footballers: a randomized controlled trial

Background

Hamstring injuries are the most common injury in Australian Rules football. It was the aims to investigate whether a sports chiropractic manual therapy intervention protocol provided in addition to the current best practice management could prevent the occurrence of and weeks missed due to hamstring and other lower-limb injuries at the semi-elite level of Australian football.

Methods

Sixty male subjects were assessed for eligibility with 59 meeting entry requirements and randomly allocated to an intervention (n = 29) or control group (n = 30), being matched for age and hamstring injury history. Twenty-eight intervention and 29 control group participants completed the trial. Both groups received the current best practice medical and sports science management, which acted as the control. Additionally, the intervention group received a sports chiropractic intervention. Treatment for the intervention group was individually determined and could involve manipulation/mobilization and/or soft tissue therapies to the spine and extremity. Minimum scheduling was: 1 treatment per week for 6 weeks, 1 treatment per fortnight for 3 months, 1 treatment per month for the remainder of the season (3 months). The main outcome measure was an injury surveillance with a missed match injury definition.

Results

After 24 matches there was no statistical significant difference between the groups for the incidence of hamstring injury (OR:0.116, 95% CI:0.013-1.019, p = 0.051) and primary non-contact knee injury (OR:0.116, 95% CI:0.013-1.019, p = 0.051). The difference for primary lower-limb muscle strains was significant (OR:0.097, 95%CI:0.011-0.839, p = 0.025). There was no significant difference for weeks missed due to hamstring injury (4 v14, χ2:1.12, p = 0.29) and lower-limb muscle strains (4 v 21, χ2:2.66, p = 0.10). A significant difference in weeks missed due to non-contact knee injury was noted (1 v 24, χ2:6.70, p = 0.01).

Conclusions

This study demonstrated a trend towards lower limb injury prevention with a significant reduction in primary lower limb muscle strains and weeks missed due to non-contact knee injuries through the addition of a sports chiropractic intervention to the current best practice management.

Trial registration

The study was registered with the Australian and New Zealand Clinical Trials Registry (ACTRN12608000533392).

Bilateral rectus femoris intramuscular haematoma following simultaneous quadriceps strain in an athlete: a case report

INTRODUCTION

Bilateral rectus femoris haematoma following a simultaneous strain of the quadriceps muscles is a very rare condition.

CASE PRESENTATION

We report the case of a 21-year-old Greek Caucasian female rowing athlete who was injured on both thighs. She complained of pain and inability to walk. Physical examination revealed tenderness over the thighs and restriction of knee movement. The result of a roentgenogram was normal, and there was no evidence of fracture or patella displacement. Magnetic resonance imaging revealed haematoma formation in both the rectus femoris muscles. The diameters of the left and right haematomas within the muscles were 6 cm and 5 cm, respectively. Therapeutic approaches included compression bandages, ice application, rest, elevation, and administration of muscle relaxant drugs. Active stretching and isometric exercises were performed after three days. The patient was able to walk using crutches two days after the initiation of treatment. On the seventh day, she had regained her full ability to walk without crutches. Non-steroidal anti-inflammatory drugs were administered on the fifth day and continued for one week. Six weeks later, she had pain-free function and the result of magnetic resonance imaging was normal. She was able to resume her training programme and two weeks later, she returned to her previous sport activities and competitions.

CONCLUSION

There are references in the literature regarding the occurrence of unilateral quadriceps haematomas following strain and bilateral quadriceps tendon rupture in athletes. Simultaneous bilateral rectus femoris haematomas after a muscle strain is a rare condition. It must be diagnosed early. The three phases of treatment are rest, knee mobilization, and restoration of quadriceps function.

Hamstring strain injuries: recommendations for diagnosis, rehabilitation, and injury prevention

Hamstring strain injuries remain a challenge for both athletes and clinicians, given their high incidence rate, slow healing, and persistent symptoms. Moreover, nearly one third of these injuries recur within the first year following a return to sport, with subsequent injuries often being more severe than the original. This high reinjury rate suggests that commonly utilized rehabilitation programs may be inadequate at resolving possible muscular weakness, reduced tissue extensibility, and/or altered movement patterns associated with the injury. Further, the traditional criteria used to determine the readiness of the athlete to return to sport may be insensitive to these persistent deficits, resulting in a premature return. There is mounting evidence that the risk of reinjury can be minimized by utilizing rehabilitation strategies that incorporate neuromuscular control exercises and eccentric strength training, combined with objective measures to assess musculotendon recovery and readiness to return to sport. In this paper, we first describe the diagnostic examination of an acute hamstring strain injury, including discussion of the value of determining injury location in estimating the duration of the convalescent period. Based on the current available evidence, we then propose a clinical guide for the rehabilitation of acute hamstring injuries, including specific criteria for treatment progression and return to sport. Finally, we describe directions for future research, including injury-specific rehabilitation programs, objective measures to assess reinjury risk, and strategies to prevent injury occurrence.

LEVEL OF EVIDENCE

Diagnosis/therapy/prevention, level 5.

Interventions for preventing hamstring injuries

BACKGROUND

Some sports, such as football, have a high incidence of hamstring injuries. Various interventions targeting the prevention of such injuries are in common use.

OBJECTIVES

To assess the effects (primarily, on the incidence of hamstring injuries) of interventions used for preventing hamstring injuries in physically active individuals.

SEARCH STRATEGY

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (to December 2008), the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2008, Issue 4), MEDLINE and other databases (to December 2008), reference lists and clinical trials registers.

SELECTION CRITERIA

Randomised or quasi-randomised trials of interventions for preventing hamstring injuries were included; as were trials testing interventions for the prevention of lower-limb injuries, provided that hamstring injuries were reported. Secondary outcomes included compliance, severity and the occurrence of other leg injuries.

DATA COLLECTION AND ANALYSIS

Two authors independently screened search results, assessed methodological quality and extracted data. Risk ratios (RR) and 95% confidence intervals (95% CI) were calculated for dichotomous variables and are reported for individual and pooled data.

MAIN RESULTS

Seven randomised controlled trials involving 1919 participants were included. All trials involved people, predominantly young adults, participating in regular sporting activities. Some trials were compromised by poor methodology, including lack of blinding and incomplete outcome data.Four trials, including 287 participants, examined interventions directly targeted at preventing hamstring injuries. Three of these trials, which tested hamstring strengthening protocols, had contradictory findings, with one small trial showing benefit (although the control rate of mainly minor hamstring injury was unusually high). The other two trials found no benefit, with a greater incidence of hamstring injury in the intervention group. One unpublished and underpowered trial provided some evidence that manual therapy may prevent lower-limb muscle strain (RR 0.13, 95% CI 0.02 to 0.97), although the finding for hamstring injury did not reach statistical significance (RR 0.21, 95% CI 0.03 to 1.66).Three trials testing interventions for preventing lower limb injuries for which data for hamstring injury were available found no statistically significant effect for hamstring injury for either proprioceptive protocols (two cluster randomised trials) or a warm up/cool down and stretching protocol (one trial).

AUTHORS' CONCLUSIONS

There is insufficient evidence from randomised controlled trials to draw conclusions on the effectiveness of interventions used to prevent hamstring injuries in people participating in football or other high risk activities for these injuries. The findings for manual therapy need confirmation.

The effect of warm-up, static stretching and dynamic stretching on hamstring flexibility in previously injured subjects

Background

Warm-up and stretching are suggested to increase hamstring flexibility and reduce the risk of injury. This study examined the short-term effects of warm-up, static stretching and dynamic stretching on hamstring flexibility in individuals with previous hamstring injury and uninjured controls.

Methods

A randomised crossover study design, over 2 separate days. Hamstring flexibility was assessed using passive knee extension range of motion (PKE ROM). 18 previously injured individuals and 18 uninjured controls participated. On both days, four measurements of PKE ROM were recorded: (1) at baseline; (2) after warm-up; (3) after stretch (static or dynamic) and (4) after a 15-minute rest. Participants carried out both static and dynamic stretches, but on different days. Data were analysed using Anova.

Results

Across both groups, there was a significant main effect for time (p < 0.001). PKE ROM significantly increased with warm-up (p < 0.001). From warm-up, PKE ROM further increased with static stretching (p = 0.04) but significantly decreased after dynamic stretching (p = 0.013). The increased flexibility after warm-up and static stretching reduced significantly (p < 0.001) after 15 minutes of rest, but remained significantly greater than at baseline (p < 0.001). Between groups, there was no main effect for group (p = 0.462), with no difference in mean PKE ROM values at any individual stage of the protocol (p > 0.05). Using ANCOVA to adjust for the non-significant (p = 0.141) baseline difference between groups, the previously injured group demonstrated a greater response to warm-up and static stretching, however this was not statistically significant (p = 0.05).

Conclusion

Warm-up significantly increased hamstring flexibility. Static stretching also increased hamstring flexibility, whereas dynamic did not, in agreement with previous findings on uninjured controls. The effect of warm-up and static stretching on flexibility was greater in those with reduced flexibility post-injury, but this did not reach statistical significance. Further prospective research is required to validate the hypothesis that increased flexibility improves outcomes.

Trial Registration

ACTRN12608000638336