Do ACL Injury Risk Reduction Exercises Reflect Common Injury Mechanisms? A Scoping Review of Injury Prevention Programs

CONTEXT

Anterior cruciate ligament (ACL) injury risk reduction programs have become increasingly popular. As ACL injuries continue to reflect high incidence rates, the continued optimization of current risk reduction programs, and the exercises contained within them, is warranted. The exercises must evolve to align with new etiology data, but there is concern that the exercises do not fully reflect the complexity of ACL injury mechanisms. It was outside the scope of this review to address each possible inciting event, rather the effort was directed at the elements more closely associated with the end point of movement during the injury mechanism.

OBJECTIVE

To examine if exercises designed to reduce the risk of ACL injury reflect key injury mechanisms: multiplanar movement, single limb stance, trunk and hip dissociative control, and a flight phase.

DATA SOURCES

A systematic search was performed using PubMed, Medline, EBSCO (CINAHL), SPORTSDiscus, and PEDro databases.

STUDY SELECTION

Eligibility criteria were as follows: (1) randomized controlled trials or prospective cohort studies, (2) male and/or female participants of any age, (3) exercises were targeted interventions to prevent ACL/knee injuries, and (4) individual exercises were listed and adequately detailed and excluded if program was unable to be replicated clinically.

STUDY DESIGN

Scoping review.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

A total of 35 studies were included, and 1019 exercises were extracted for analysis.

RESULTS

The average Consensus on Exercise Reporting Template score was 11 (range, 0-14). The majority of exercises involved bilateral weightbearing (n = 418 of 1019; 41.0%), followed by single limb (n = 345 of 1019; 33.9%) and nonweightbearing (n = 256 of 1019; 25.1%). Only 20% of exercises incorporated more than 1 plane of movement, and the majority of exercises had sagittal plane dominance. Although 50% of exercises incorporated a flight phase, only half of these also involved single-leg weightbearing. Just 16% of exercises incorporated trunk and hip dissociation, and these were rarely combined with other key exercise elements. Only 13% of exercises challenged more than 2 key elements, and only 1% incorporated all 4 elements (multiplanar movements, single limb stance, trunk and hip dissociation, flight phase) simultaneously.

CONCLUSION

Many risk reduction exercises do not reflect the task-specific elements identified within ACL injury mechanisms. Addressing the underrepresentation of key elements (eg, trunk and hip dissociation, multiplanar movements) may optimize risk reduction in future trials.

Do currently prescribed exercises reflect contributing pathomechanics associated with femoroacetabular impingement syndrome? A scoping review

OBJECTIVE

Research reports limited, mixed evidence on the effectiveness of physiotherapy management in the treatment of femoroacetabular impingement (FAI) syndrome. The purpose of this review was to (1) identify what therapeutic exercises are being utilized in the non-surgical management of patients with FAI syndrome; (2) map the extent to which reported exercises reflect contributory pathomechanics associated with FAI syndrome.

DESIGN

Scoping Review.

METHODS

MEDLINE, PubMed, CINAHL, SPORTDiscus, and PEDRO electronic databases were searched for studies that implemented a non-surgical, exercise-based treatment approach in patients with FAI syndrome. Exercises were extracted and analyzed according to elements recognized as contributing to the pathomechanics associated with FAI syndrome.

RESULTS

24 studies fulfilled the inclusion criteria. 453 exercises were extracted. Uniplanar exercises accounted for 338/453 or 74.6% of all reported exercises whereas triplanar exercises accounted for 21/453 or 4.6% of all exercises. Non-weight bearing exercises accounted for 220/453 or 48.6% of all exercises.

CONCLUSION

The majority of therapeutic exercises were classified as sagittal, uniplanar exercises, utilizing a concentric exercise approach. These findings highlight that exercises utilizing triplanar, eccentric hip control, in a single limb weightbearing position are considerably underrepresented.

Do exercises for patellofemoral pain reflect common injury mechanisms? A systematic review

OBJECTIVES

Current best evidence has reported that therapeutic exercise programs that are designed to treat patellofemoral pain (PFP) should include both hip and knee specific exercises. The purpose of this review was to (1) examine the quality/comprehensiveness of exercise reporting in this field; (2) quantify the extent to which individual exercises comprised task-specific elements (single limb stance; eccentric control of the hip; rotational z-axis control) most likely to address key pathomechanics associated with PFP.

DESIGN

Systematic review: a systematic survey of RCTs.

METHODS

PubMed, CINAHL, Medline, Physiotherapy Evidence Database (PEDro) and SPORT Discus databases were searched for randomized controlled trials that addressed PFP utilizing a proximal control hip focused rehabilitation paradigm. The therapeutic exercise programs were evaluated, and each individual exercise was extracted for analysis. Quality assessments included the PEDro Scale and the Consensus on Exercise Reporting Template (CERT) was utilized to score the reporting of the interventions.

RESULTS

19 studies were included in the final analysis. 178 total exercises were extracted from the proximal hip and knee rehabilitation programs. The exercises were analyzed for the inclusion of elements that align with reported underlying biomechanical mechanisms.

CONCLUSIONS

The vast majority of the exercises were sagittal plane, concentric, non-weight bearing exercises, whereas multiplanar exercises, single limb weightbearing, and exercises where loading was directed around the longitudinal z-axis, were considerably under-represented. Current exercises for PFP utilize simplistic frameworks that lack progression into more task specific exercise, and are not reflective of the complex injury etiology.

FRAMEWORK FOR OPTIMIZING ACL REHABILITATION UTILIZING A GLOBAL SYSTEMS APPROACH

Knee injuries such as ACL tears commonly occur and there is a high re-injury rate after primary ACL reconstruction with figures estimated at 25%-33%. Clinicians often use hip strengthening as a key component of knee rehabilitation. Evidence suggests that adopting a "regional" or "proximal" approach to rehabilitation can increase hip strength, but motor control often remains unchanged, particularly during more complex tasks such as running and jumping. It has been previously suggested that the current approach to "regional/proximal" rehabilitation is too basic and is constrained by a reductionist philosophy. This clinical commentary provides the clinician a framework for optimizing knee rehabilitation, underpinned by a more global approach. Although this approach remains hip-focused, it can be easily adapted to modify exercise complexity and key loading variables (speed, direction, flight), which will help the clinician to better replicate the sport specific demands on the knee.

LEVEL OF EVIDENCE

5.

Jump load and landing patterns of collegiate female volleyball players during practice and competition

BACKGROUND

Overuse lower extremity injuries are common in women's court volleyball players and are likely due to the repetitive jumping and landing the sport requires. The purpose of this study was to quantify jump load during collegiate women's volleyball, describe the quantity of double-leg (DL) to single-leg (SL) landing strategies, and compare loads and landing strategies between games and practices.

METHODS

Fourteen collegiate Division-1 women's court volleyball players participated in the study. Volleyball-specific activity demands were quantified using video analysis from three consecutive practices and one match. Investigators recorded the total frequency of jump landings, and the frequency and percentage of double-leg (DL) landings and single-leg (SL) landings of fourteen collegiate Division-1 women's court volleyball players. Repeated measures ANOVAs identified differences in jumping load and percentages of DL and SL landings among practices and between practices and games (P<0.05).

RESULTS

On average, there was a significantly higher overall jumping load (P=0.01) and frequency of DL (P=0.03) and SL (P=0.04) landings during practice than games, yet no differences between practices (P>0.05). Approximately 75% of all landings were DL, and individual patterns of DL to SL landings were consistent across events (P>0.05).

CONCLUSIONS

Women's collegiate volleyball demands high volumes of repetitive jumping and landing with SL and DL support that may make these athletes susceptible to overuse injuries, especially during practice.

Activity Demands During Multi-Directional Team Sports: A Systematic Review

BACKGROUND

Late-stage rehabilitation programs often incorporate 'sport-specific' demands, but may not optimally simulate the in-game volume or intensity of such activities as sprinting, cutting, jumping, and lateral movement.

OBJECTIVE

The aim of this review was to characterize, quantify, and compare straight-line running and multi-directional demands during sport competition.

DATA SOURCES

A systematic review of PubMed, CINAHL, SPORTDiscus, and Cochrane Central Register of Controlled Trials databases was conducted.

STUDY ELIGIBILITY CRITERIA

Studies that reported time-motion analysis data on straight-line running, accelerations/decelerations, activity changes, jumping, cutting, or lateral movement over the course of an entire competition in a multi-directional sport (soccer, basketball, lacrosse, handball, field hockey, futsal, volleyball) were included.

STUDY APPRAISAL AND SYNTHESIS METHODS

Data was organized based on sport, age level, and sex and descriptive statistics of the frequency, intensity, time, and volume of the characteristics of running and multi-directional demands were extracted from each study.

RESULTS

Eighty-one studies were included in the review (n = 47 soccer, n = 11 basketball, n = 9 handball, n = 7 field hockey, n = 3 futsal, n = 4 volleyball). Variability of sport demand data was found across sports, sexes, and age levels. Specifically, soccer and field hockey demanded the most volume of running, while basketball required the highest ratio of high-intensity running to sprinting. Athletes change activity between 500 and 3000 times over the course of a competition, or once every 2-4 s. Studies of soccer reported the most frequent cutting (up to 800 per game), while studies of basketball reported the highest frequency of lateral movement (up to 450 per game). Basketball (42-56 per game), handball (up to 90 per game), and volleyball (up to 35 per game) were found to require the most jumping.

LIMITATIONS

These data may provide an incomplete view of an athlete's straight-line running load, considering that only competition and not practice data was provided.

CONCLUSIONS

Considerable variability exists in the demands of straight-line running and multi-directional demands across sports, competition levels, and sexes, indicating the need for sports medicine clinicians to design future rehabilitation programs with improved specificity (including the type of activity and dosage) to these demands.

Rehabilitation Exercises Reduce Reinjury Post Ankle Sprain, But the Content and Parameters of an Optimal Exercise Program Have Yet to Be Established: A Systematic Review and Meta-analysis

OBJECTIVES

To determine if exercise-based rehabilitation reduces reinjury following acute ankle sprain. Our secondary objective was to assess if rehabilitation efficacy varies according to exercise content and training volume.

DATA SOURCES

The following electronic databases were searched: EMBASE, MEDLINE, the Cochrane Central Register of Controlled Trials, and Physiotherapy Evidence Database (PEDro).

STUDY SELECTION

Randomized controlled trials investigating the effect of exercise-based rehabilitation programs on reinjury and patient-reported outcomes (perceived instability, function, pain) in people with an acute ankle sprain. No restrictions were made on the exercise type, duration, or frequency. Exercise-based programs could have been administered in isolation or as an adjunct to usual care. Comparisons were made to usual care consisting of 1 or all components of PRICE (protection, rest, ice, compression, elevation).

DATA EXTRACTION

Effect sizes with 95% CIs were calculated in the form of mean differences for continuous outcomes and odds ratios (ORs) for dichotomous outcomes. Pooled effects were calculated for reinjury prevalence with meta-analysis undertaken using RevMan software.

DATA SYNTHESIS

Seven trials (n=1417) were included (median PEDro score, 8/10). Pooled data found trends toward a reduction in reinjury in favor of the exercise-based rehabilitation compared with usual care at 3-6 months (OR, 0.87; 95% CI, 0.48-1.58) with significant reductions reported at 7-12 months (OR, 0.53; 95% CI, 0.38-0.73). Sensitivity analysis based on pooled reinjury data from 2 high quality studies (n=629) also found effects in favor of exercise-based rehabilitation at 12 months (OR, 0.60; 95% CI, 0.49-0.89). Training volume differed substantially across rehabilitation programs with total rehabilitation time ranging from 3.5-21 hours. The majority of rehabilitation programs focused primarily on postural balance or strength training.

CONCLUSIONS

Exercise-based rehabilitation reduces the risk of reinjury following acute ankle sprain when compared with usual care alone. There is no consensus on optimal exercise content and training volume in this field. Future research must explicitly report all details of administered exercise-based rehabilitation programs.

Exercise prescription for overhead athletes with shoulder pathology: a systematic review with best evidence synthesis

OBJECTIVE

To produce a best evidence synthesis of exercise prescription used when treating shoulder pathology in the overhead athlete.

DESIGN

A systematic review of exercises used in overhead athletes including case studies and clinical commentaries.

DATA SOURCES

MEDLINE, PubMed, SPORTDiscus and CINAHL from database inception through July 8, 2016.

METHODS

We examined data from randomised controlled trials and prospective cohort (level I-IV evidence) studies that addressed exercise intervention in the rehabilitation of the overhead athlete with shoulder pathology. Case studies and clinical commentaries (level V evidence) were examined to account for expert opinion-based research. Data were combined using best evidence synthesis and graded (A-F) recommendations (Centre for Evidence-Based Medicine).

RESULTS

There were 33 unique exercises in six level I-IV studies that met our inclusion criteria. Most exercises were single-plane, upper extremity exercises performed below 90^o of elevation. There were 102 unique exercises in 33 level V studies that met our inclusion criteria. These exercises emphasised plyometrics, kinetic chain and sport-specific training.

CONCLUSIONS AND RELEVANCE

Overall, evidence for exercise interventions in overhead athletes with shoulder pathology is dominated by expert opinion (grade D). There is great variability between exercise approaches suggested by experts and those investigated in research studies and the overall level of evidence is low. The strongest available evidence (level B) supports the use of single-plane, open chain upper extremity exercises performed below 90° of elevation and closed chain upper extremity exercises. Clinical expert pieces support a more advanced, global treatment approach consistent with the complex, multidimensional nature of sport.

An evidence-based review of hip-focused neuromuscular exercise interventions to address dynamic lower extremity valgus

Deficits in proximal hip strength or neuromuscular control may lead to dynamic lower extremity valgus. Measures of dynamic lower extremity valgus have been previously shown to relate to increased risk of several knee pathologies, specifically anterior cruciate ligament ruptures and patellofemoral pain. Therefore, hip-focused interventions have gained considerable attention and been successful in addressing these knee pathologies. The purpose of the review was to identify and discuss hip-focused exercise interventions that aim to address dynamic lower extremity valgus. Previous electromyography, kinematics, and kinetics research support the use of targeted hip exercises with non-weight-bearing, controlled weight-bearing, functional exercise, and, to a lesser extent, dynamic exercises in reducing dynamic lower extremity valgus. Further studies should be developed to identify and understand the mechanistic relationship between optimized biomechanics during sports and hip-focused neuromuscular exercise interventions.