Early Sport Specialization…

Growing up and playing competitive hockey, my goal was always to obtain a college scholarship and maybe, just maybe make it to that next level. So, I did what any other talented young athlete would do, listen to well-meaning coaches and scouts and focus all of my energy on MY sport at a young age. I thoroughly enjoyed playing hockey and was happy to play 2 hours, 5 times a week year-round…

My story of early specialization is all too common in competitive athletics. A recent study by Post and colleagues found that the vast majority of division 1 athletes that specialize early do so because…

The most common reason cited by athletes for choosing to specialize in their college sport was enjoying that sport the most. The second and third most frequent selections were having an opportunity to earn a scholarship to play in college and being the best at that sport, respectively. Only 9.9% (n = 34) of athletes cited parental influence as the most important factor in their decision to specialize in their college sport. — Post et al., 2017

All of these reasons make perfect sense, but do athletes who specialize early actually have more success than multi-sport athletes?

According to the same study, the prevalence of highly specialized athletes (year round training of > 8 months per year, chose a single main sport, and quit all sports to focus on a single sport) increased significantly from freshman (16.9%) to senior year (41.1%) of high school. In a separate study, amongst high school athletes, 29.5% classified themselves as one-sport athletes and 36.4% were considered highly specialized in their chosen sport. Based on this information, there does not seem to be a significant difference between division 1 athletes and the general high school athlete population with regards to specialization.

Furthermore, approximately 90% of 2016 and 2017 NFL draft picks played multiple sports during high school. In agreement with this trend, 100% of 2016 national college football award winners, including all 5 Heisman Trophy finalists, were not highly specialized or single-sport athletes in high school. And looking closer at the two teams who played in Super Bowl LI, approximately 87% of the players on both teams were multi-sport athletes in high school. The current evidence does not necessarily look favorable for the highly specialized athlete.

More importantly, how does early specialization impact risk of injury?

In order to be successful, you need to be healthy and the literature once again does not give favor to specialization. Athletes with high competition volume, who participated in a club sport, or who were highly specialized had 2.08 times greater odds of reporting a previous lower extremity injury than those with low competition volume, 1.50 times greater odds than no club sport participation, and 2.58 times greater odds in comparison to low specialization. Building upon this information, another study found that highly specialized athletes were more likely to report a previous injury of any kind or an overuse injury in the previous year compared with athletes in the low specialization group. Athletes who played their primary sport more than 8 months of the year were 1.68 times more likely to report an upper extremity overuse injury or 1.66 times more likely to sustain a lower extremity overuse injury. When looking at serious overuse injuries, highly specialized athletes were 2.38 times more likely than multi-sport athletes.

When looking closer at ice hockey, one of the most common areas of injury tends to revolve around the hip/pelvic region. Being that highly specialized athletes are 2.74 times more likely to sustain an overuse injury to this region, this should be an area of specific concern… 

Femoroacetabular Impingement Syndrome (FAIS) is an abnormal growth of bone localized to the femoral neck and/or acetabular rim. In the case of Cam morphology (increased bone growth on femoral neck), the prevalence significantly increases in ice hockey players as they age. Even when compared to a similar group of athletes (skiers), the ice hockey group showed a consistent increase in prevalence as age increases. While this altered morphology may not result in a painful condition, as a recent study showed prevalence of FAIS in 68% of ice hockey players with only 22% demonstrating symptoms. This increased prevalence of altered hip/pelvic morphology speaks to the repetitive nature of the sport (especially among goaltenders) and may predispose them to hip/groin pathology as their career progresses.

Moving to the psychological impact of sport specialization, there is also evidence to support increased levels of drop out in those highly specialized athletes.

Among ice hockey players, those who began off-ice training earlier and those that invested a larger number of hours training at a younger age were more likely to drop-out of their sport. This study showed that hockey players started playing at 5 years old and the athletes that ended up dropping out began off-ice training at 11.75 years old in comparison to 13.8 years old in those who continued playing. Additionally, those that continued playing their sport invested an average of 6.8 hours to off-ice training versus 107 hours per year in the drop out group.

Dropout can occur for any number of reasons spanning from psychological to physical factors. Studies looking into reasoning behind burnout in competitive tennis players found burned-out players had less input into training and sport-related decisions and practiced fewer days with decreased motivation. While sport specialization has not necessarily been linked to burnout, the underlying stressors related to the early and highly specialized athlete mimic those reasons for dropout.

Knowing the negative impact of early and high specialization in one sport, what can we as athletes, coaches, parents, and healthcare providers do? 

  1. Take a break. Actually take the off-season off and find another sport or passion during this time.
  2. Develop overall athleticism. There is a reason multi-sport athletes are generally more successful at higher levels. They have been exposed to different movements and stresses that their primary sport does not provide them.
  3. Listen to your body and your mind. Are you feeling burnt out or are you suffering from a nagging injury? Take the time to have these factors addressed… See a physical therapist, see a sports psychologist, or see the appropriate medical professional.
  4. HAVE FUN. Sports are meant to be a positive influence on your life, not a drain on you physically and mentally.

We as a culture need to make a change in how youth and competitive sports are positioned. The highly specialized athlete is not necessarily more successful, is more likely to sustain an overuse or serious injury, and demonstrates the psychological profile of those that drop-out of their sport. We need to embrace the need for varying experiences and movement activities. The literature is fairly definitive and we need to push our children, athletes, and coaches to focus on the enjoying their athletic career and on developing overall athleticism during this timeframe.

References:

1. Bell DR, Post EG, Trigsted SM, Hetzel S, McGuine TA, Brooks MA. Prevalence of Sport Specialization in High School Athletics: A 1-Year Observational Study. Am J Sports Med. 2016;44(6):1469-1474. doi:10.1177/0363546516629943.
2. Brunner R, Maffiuletti NA, Casartelli NC, et al. Prevalence and Functional Consequences of Femoroacetabular Impingement in Young Male Ice Hockey Players. Am J Sports Med. 2015;44(1):46-53. doi:10.1177/0363546515607000.
3. Fabricant PD, Lakomkin N, Sugimoto D, Tepolt FA, Stracciolini A, Kocher MS. Youth sports specialization and musculoskeletal injury: a systematic review of the literature. The Physician and Sportsmedicine. 2016;44(3):257-262. doi:10.1080/00913847.2016.1177476.
4. Feeley BT, Agel J, LaPrade RF. When Is It Too Early for Single Sport Specialization? Am J Sports Med. 2016;44(1):234-241. doi:10.1177/0363546515576899.
5. Gould D, Tuffey S, Udry E, Loehr JE. Burnout in competitive junior tennis players: III. Individual differences in the burnout experience. Sport Psychol. 1997;11:257-276.
6. Gould D, Tuffey S, Udry E, Loehr JE. Burnout in competitive junior tennis players: II. Qualitative analysis. Sport Psychol. 1996;10:341-366.
7. Gould D, Udry E, Tuffey S, Loehr JE. Burnout in competitive junior tennis players: I. A quantitative psychological assessment. Sport Psychol. 1996;10:322- 340.
8. Jayanthi NA, LaBella CR, Fischer D, Pasulka J, Dugas LR. Sports-specialized intensive training and the risk of injury in young athletes: a clinical case-control study. Am J Sports Med. 2015;43(4):794-801. doi:10.1177/0363546514567298.
9. Myer GD, Jayanthi N, Difiori JP, et al. Sport Specialization, Part I: Does Early Sports Specialization Increase Negative Outcomes and Reduce the Opportunity for Success in Young Athletes? Sports Health: A Multidisciplinary Approach. 2015;7(5):437-442. doi:10.1177/1941738115598747.
10. Myer GD, Jayanthi N, Difiori JP, et al. Sports Specialization, Part II: Alternative Solutions to Early Sport Specialization in Youth Athletes. Sports Health: A Multidisciplinary Approach. 2016;8(1):65-73. doi:10.1177/1941738115614811.
11. Pasulka J, Jayanthi N, McCann A, Dugas LR, LaBella C. Specialization patterns across various youth sports and relationship to injury risk. The Physician and Sportsmedicine. April 2017:1-9. doi:10.1080/00913847.2017.1313077.
12. Philippon MJ, Ho CP, Briggs KK, Stull J, LaPrade RF. Prevalence of Increased Alpha Angles as a Measure of Cam-Type Femoroacetabular Impingement in Youth Ice Hockey Players. American Journal of Sports Medicine. April 2013. doi:10.1177/0363546513483448.
13. Post EG, Bell DR, Trigsted SM, et al. Association of Competition Volume, Club Sports, and Sport Specialization With Sex and Lower Extremity Injury History in High School Athletes. Sports Health: A Multidisciplinary Approach. 2017;34:1941738117714160. doi:10.1177/1941738117714160.
14. Post EG, Thein-Nissenbaum JM, Stiffler MR, et al. High School Sport Specialization Patterns of Current Division I Athletes. Sports Health: A Multidisciplinary Approach. 2017;9(2):148-153. doi:10.1177/1941738116675455.
15. Post EG, Trigsted SM, Riekena JW, et al. The Association of Sport Specialization and Training Volume With Injury History in Youth Athletes. Am J Sports Med. 2017;45(6):1405-1412. doi:10.1177/0363546517690848.
16. Wall M, Côté J. Developmental activities that lead to dropout and investment in sport. Physical Education & Sport Pedagogy. 2007;12(1):77-87. doi:10.1080/17408980601060358.

Review: MedBridgeGO Patient HEP app

Patient compliance is an integral piece of the rehabilitation puzzle. Patients being consistent with their prescribed home exercise program depends on several factors, however there are two aspects that stand out beyond the rest.

  1. Forming a Therapeutic Alliance with the patient and getting buy-in that their program will help them achieve THEIR goals
  2. Providing a thorough, efficient, and easy to use resource so that they can feel confident in the performance of their program.

While the first aspect of the puzzle relies on the clinician and their ability to educate and coach their patient, the second aspect can be accomplished with the correct technology. Recently, Medbridge came out with their MedBridgeGO app to compliment their growing Home Exercise Program. I have been using both the HEP and app for the past month and below are my thoughts…

How it Works:

1. You use MedBridge’s VERY easy to use home exercise program

screen-shot-2017-07-08-at-4-19-17-pm.png

2. The patient downloads and accesses MedbridgeGO, then inputs their access code (provided by their PT)

3. Their session begins…

This slideshow requires JavaScript.

Additional Features:

1. Patient education resources that are modifiable are also available to be accessed via the MedbridgeGO application. This allows the patient easy access to information regarding their condition.

2. The ability to set a reminder in order to improve patient compliance.

This feature gives your patients the ability to set an alarm that will automatically sync with their phone’s alarm system. This allows for the patient to have continual reminders that they need to do their homework. In theory, this eliminates the, “I forgot” excuse.

1. Ease of Use

The program is very easy to use and I have been able to utilize it with patients in their teens (much more successfully) and my geriatric population (with a bit more coaching). There will always be patients that prefer a paper home exercise program whether because they prefer that medium or they do not feel comfortable with the technology. All menus and screens spell out what needs to be done and it is presented in a very clear, simple manner.

2. Accuracy of Program

With over 4,000 exercises and 150 patient education resources, there is ample to choose from when making your patient’s home exercise program. That being said, if something has not found its way into their database yet, you do have the ability to add your own exercises/patient education or modify existing content. All exercises chosen in the HEP transferred seamlessly to the MedbrdgeGO app throughout my use to this point.

3. Patient Compliance

The added benefit in this system is being able to see when patients actually performed their HEP… Some patients can be a but ‘misleading’ in their responses. Outside of this additional checks and balances, I have found that giving my patients an easy to perform and easy to access home exercise program has led to increased compliance and accuracy of exercise performance throughout my time using the program.

Screen Shot 2017-07-16 at 11.11.37 AM

4. Overall

This program gives the therapist all of the tools needed to provide a simple, effective home exercise program. The program itself is not for everyone because it does require a requisite comfort level with technology, however this has been a much smaller population than I had expected.

As great as the program is, there are a few areas that do need addressed moving forward. The exercise program is based on a timer that is calculated based on the sets and reps chosen by the therapist. However, as we know, patients perform movements with varying levels of ease and speed. This can make some patients feel as though they are lagging behind throughout the program. Additionally, this issue especially comes through when giving patients a hold time during their exercise (i.e. hold a bridge for 5 seconds or long duration isometrics for 30 seconds) since the current time calculation does not account for this. By having the patient ‘pause’ their program, this issue can be worked around.

The MedbridgeGO app gives the clinician and patient the ability to ensure that they are 100% on the same page with regards to exercise performance and frequency of performance. It has a few small areas that need addressed (and I am sure they will be), but overall adding this program has been incredibly beneficial to my patient care and I will continue to utilize it moving forward.

Ice Hockey Injuries: Who Gets Hurt and Why Does it Matter?

Ice hockey is an inherently physical sport and as such creates situations where injury is possible and often likely. With the influence that injuries can have on a team’s success, research has started to focus on our ability to assess injury risk and prevent injuries before they occur. However, these strategies cannot be effectively laid out until we first understand who gets hurt, when they get hurt, and how they get hurt.

Who gets hurt?

According to a prospective cohort study performed by Flik et al., there is a significant disparity in injury incidence depending upon player position in NCAA Division 1 ice hockey. Only 6.2% of injuries were sustained by goaltenders, whereas 32.7% were defensemen and 61.1% were forwards. In agreement with this distribution, Agel et al found 9.6% of injuries effected goaltenders, 40.8% were defensemen, and 48.3% were forwards. This information also correlated with a recent study investigating injury incidence during the World Championship and Olympic tournaments, where goaltenders were once again the least injured followed by defensemen and forwards. However, when evaluating injuries in the National Hockey League (NHL), the only significant difference found was a higher likelihood of defensemen missing gametime due to injury in comparison to forwards. This study also found that a significant predictor of missing at least 5 games due to injury included being a goaltender (odds ratio = 1.68). So, while goaltenders do not get injured as often, their return to play is often more extended in comparison to other players. These numbers are likely not as drastically position dependent due to the disparity of position players on the ice at one time (3 forwards, 2 defensemen, and 1 goaltender), which may account for a significant amount of the variance reported in the literature at the collegiate, international, and professional levels.

When do they get hurt?

Understanding when injuries occur during the course of an individual game and throughout the course of the season allows us to understand when an athlete is at an increased risk of injury. With regards to the collegiate level, 65.5% of injuries occur during games and 35.5% during practice. Additionally, preseason practice rates were more than twice as high as in season injury rates. Two studies looked into the distribution of injuries during game play and found drastically different results. Agel and colleagues found that most injuries occurred in the 2nd and 3rd periods, which is likely due to athlete fatigue and intensity of gameplay increasing as the game progresses. In contrast to this report, amongst NHL regular season injuries, the vast majority occur in the first period (48.1%). Intuitively, as the NHL season progresses, the likelihood of injury also increases. This increase in injury rate is likely due to player fatigue and increased intensity of play as teams are fighting for a playoff spot.

How do they get hurt?

Due to the physical nature of ice hockey, the vast majority of injuries are contact-related, however non-contact injuries tend to make up a higher proportion of practice injuries. According to Agel and colleagues, non-contact injuries make up 9.7% of injuries during games, whereas they make up 32% of injuries during practice. During games, approximately 50% of injuries are due to contact with another player and 39.6% are due to contact with another object (boards, puck, etc.). In agreement with these trends, in the NHL body checking made up 28.6% of injuries, while incidental contact (14.3%), hit by puck (13.5%), contact with environment (9.4%), and other intentional player contact (7.4%) made up the bulk of injuries incurred. Aside from these mechanisms, non-contact injuries made up 14.8% of all injuries and accounted for 11.7% of man games lost due to injury (1,921 games) between 2009 and 2012. This gives good insight into the general cause of injury, but what types of injury are most common amongst ice hockey players?

Over a 16 season timeframe, injures most often sustained during gameplay included internal derangement of the knee (13.5%), concussion (9.0%), acromioclavicular joint injury (8.9%), upper leg contusion (6.2%), and musculotendinous strain of the hip/groin region (4.5%). However, distribution of injuries during practice shows a slightly different distribution. The most common injuries during practice were musculotendinous strain of the hip/groin region (13.1%), internal derangement of the knee (10.1%), ankle ligament sprain (5.5%), concussion (5.3%), and acromioclavicular joint injury (4.4%). Looking further at this data, during games, the highest prevalence of severe injuries was knee internal derangement and the most common mechanism of injury was due to player contact. Of the most common severe injuries reported, musculotendinous injuries of the pelvis/hip was the only pathology (6.2%) that had a non-contact mechanism as the most common cause. In agreement with these findings, amongst NHL players, the most common sites of injury include the head (17%), thigh (14%), knee (13%), and shoulder (12%). Additionally, with regards to man games lost, these regions also comprised the largest impact on their respective teams. Unfortunately, this study did not break the body regions into specific injuries/pathologies.

Given the fairly vague description of the injuries reported in these large epidemiological studies, it is also important to look more in depth to determine which specific injuries are actually reported in the literature. With regards to knee ligamentous injuries, Sikka and colleagues found that between 2006 and 2010, only 47 players sustained an anterior cruciate ligament tear in the NHL, which is significantly lower than most professional contact team sports. These injuries included 3 goaltenders, 8 defensemen, and 36 forwards. Of these 47 injuries, the reported mechanism for all but one injury was contact with another player and/or with the boards. In addition to the primary ACL rupture, 68% of injuries reported a concomitant meniscal or medical collateral ligament injury as well. Looking at the more commonly injured MCL, from 2003-04 to 2010-11, 13 MCL injuries were reported within one collegiate ice hockey program. This resulted in ten different players being injured (12.7%) and an incident rate of 0.44 per 1,000 athlete exposures. Of these injuries, 77% were contact related and an acute non-contact injury was reported in 15% of cases.

Looking at the most common non-contact injury, hip/pelvic pathology has also been investigated in the literature for this population. Over a four year span, 890 hip or groin injuries were reported in the NHL. Of those reported, 10.6% were found to be intra-articular in nature. There was a very small difference between injury occurring during games (44.6%) and during practice (41.4%), but the vast majority occurred during the regular season (71.2%). The most frequent intra-articular hip diagnosis made in this cohort was hip labral tear (69.1%), followed by hip osteoarthritis (13.8%), hip loose body (6.3%), femoroactebular impingement (5.3%), other hip injury (3.1%), and hip chondromalacia (2.12%). With regards to player position, injuries per 1000 player-game appearances were significantly higher in goaltenders compared with all other players.

Why does it matter?

Having a successful team depends on multiple factors, but regardless of coaching or talent, injuries can have a significant impact on a team’s ability to win. Unfortunately, the NHL does not readily provide injury data to the general public, however ManGamesLost.com has provided data supporting the negative impact of injuries on a team’s success. Over the past five seasons, the Stanley Cup champion has been among the top five least injured teams throughout the regular season. Along those same lines, this season’s President’s Trophy (best regular season record) winning Washington Capitals also had the least man games lost due to injury. Additionally, with the exception of the Pittsburgh Penguins, none of the top five most injured teams have had consistent success over the past five years. In fact, two of those included in the top five most injured also had the two of the worst overall records over this timeframe (Columbus Blue Jackets and Edmonton Oilers).

Screen Shot 2016-04-24 at 3.29.05 PM

In addition to the obvious impact on team performance, when a player returns from a significant injury, their productivity and durability has the potential to decline in the seasons following their return to play. The presence of a meniscal injury was associated with a decreased length of career for all positions. Furthermore, for wings and centers, the number of games played decreased in the first full season after ACL injury from 71.2 to 58.2 and in the second full season to 59.29. With regard to offensive production, there was a 31% reduction in goals scored per season, 60% reduction in assists, and 42% reduction in total points compared with an uninjured control group. Only 37.5% of players who were previously selected as All-Stars were able to regain this honor upon their return to play.

Finally, there is also a financial impact as well. According to Donaldson and colleagues, between the 2009-10 and 2011-12 seasons, 50.9% of NHL players missed at least one game, which translated to a total salary cost of $218 million per year.

With the substantial impact on team performance and the associated financial implications, understanding how to identify those at risk and develop programs to lessen the likelihood of injury are paramount to a successful organization. Part 2 of this series will delve into the evidence regarding injury risk assessment and prevention in this population of athletes.

References:

1. Agel J, Dompier T, Dick R, Marshall S. Descriptive Epidemiology of Collegiate Men’s Ice Hockey Injuries: National Collegiate Athletic Association Injury Surveillance System, 1988–1989 Through 2003–2004. Journal of Athletic Training. 2007;42(2):241-248.

2. Flik K. American Collegiate Men’s Ice Hockey: An Analysis of Injuries. American Journal of Sports Medicine. 2005;33(2):183-187. doi:10.1177/0363546504267349.

3. Currier, Nathan. “The Most Injured NHL Teams Since the 2009-2010 Season.” ManGamesLost.com. N.p., 12 Apr. 2016. Web. 22 Apr. 2016.

4. Donaldson L, Li B, Cusimano MD. Economic burden of time lost due to injury in NHL hockey players. Inj Prev. 2014;20(5):347-349. doi:10.1136/injuryprev-2013-041016.

5. Epstein DM, McHugh M, Yorio M, Neri B. Intra-articular Hip Injuries in National Hockey League Players: A Descriptive Epidemiological Study. American Journal of Sports Medicine. 2013;41(2):343-348. doi:10.1177/0363546512467612.

6. Grant JA, Bedi A, Kurz J, Bancroft R, Miller BS. Incidence and Injury Characteristics of Medial Collateral Ligament Injuries in Male Collegiate Ice Hockey Players. Sports Health. 2013;5(3):270-272. doi:10.1177/1941738112473053.

7. McKay CD, Tufts RJ, Shaffer B, Meeuwisse WH. The epidemiology of professional ice hockey injuries: a prospective report of six NHL seasons. British Journal of Sports Medicine. 2014;48(1):57-62. doi:10.1136/bjsports-2013-092860.

8. Sikka R, Kurtenbach C, Steubs JT, Boyd JL, Nelson BJ. Anterior Cruciate Ligament Injuries in Professional Hockey Players. American Journal of Sports Medicine. 2016;44(2):378-383. doi:10.1177/0363546515616802.

9. Tuominen M, Stuart MJ, Aubry M, Kannus P, Parkkari J. Injuries in men’s international ice hockey: a 7-year study of the International Ice Hockey Federation Adult World Championship Tournaments and Olympic Winter Games. British Journal of Sports Medicine. 2015;49(1):30-36. doi:10.1136/bjsports-2014-093688.

The Importance of Isometrics

An isometric contraction is a static form of exercise in which a muscle contracts to produce force without an appreciable change in muscle length and without visible joint movement1 We learn these basic concepts in school and are told to provide these types of interventions during the early phases of rehabilitation, but do we truly understand the benefit of these seemingly simple exercises?

Eccentrics versus Isometrics

While eccentric exercise is the mainstay of most rehabilitation programs for tendinopathies, some patients find them painful to complete and difficult to perform.2 In these cases, patient compliance suffers due to increased pain, leading to underwhelming outcomes.3

Conversely, the impact of isometric contraction on pressure pain thresholds (PPTs) yields promising results. When asymptomatic volunteers held a quadriceps isometric contraction at 21% MVIC until exhaustion (maximum of 5-minute duration), patients demonstrated a significant increase in PPT at the start of contraction. PPT continued to increase until the middle of the contraction period and stayed increased for up to 5 minutes post-intervention.4

Reduced Perceived Pain

In a similar study, PPTs were determined after 14 healthy women completed 2 sets of submaximal (40-50% MVIC) isometric exercise consisting of squeezing a dynamometer for 2 minutes with their dominant hand.5 This trial demonstrated a positive contralateral and ipsilateral hypoalgesic effect with elevated PPTs and a reduction in self-perceived pain rating for both hands following isometric exercise. While this provides a good foundation of support, it does not provide information regarding isometric exercise’s effect on individuals with a painful condition

To answer this question, Rio and associates performed a randomized cross-over study to investigate the hypoalgesic impact of a single bout of isometric contractions on individuals with patellar tendinopathy.6 Those in the intervention group performed 5 sets of 45 second isometric quadriceps contractions (70% MVIC) with a 2 minute rest break between each set. Those in the control group performed 4 sets of 8 repetitions (100% 8-repition maximum) of an isotonic leg extension exercise with a 4 second eccentric phase and 3 second concentric phase.

At the conclusion of the study, isometric contractions reduced pain during single-leg decline squat from 7.0 to 0.17 on an 11-point scale and increased MVIC by 18%. Both values were maintained for 45 minutes post-intervention. Also, cortical inhibition increased from 27.5% to 54.9%, which may factor into the underlying mechanism of this hypoalgesia.7

Further supporting the hypoalgesic properties of isometric contractions, Rio and colleagues once again added to the depth of literature in this area. They used a within-session randomized controlled trial to compare isometric leg extension at 60 degrees of knee flexion to isotonic leg extension in volleyball or basketball players with patellar tendinopathy. At the conclusion of the study, those randomized to the isometric knee extension group demonstrated significantly greater immediate analgesia throughout the 4 weeks trial.8

Back to the Basics

Isometrics are not simply an introductory exercise for patients following a post-operative procedure (i.e. quad sets following ACL reconstruction). Their hypoalgesic effects are far more impactful then most of us recognize. Although we are not sure why isometrics are efficacious in these tendinopathies, they give us an intervention that is successful.  Clinicians often get too caught up in complex and intricate treatment philosophies when in reality all we have to do is go back to the basics!

References

1. Kisner, Carolyn, and Lynn Allen. Colby. Therapeutic Exercise: Foundations and Techniques. 5th ed. Philadelphia: F.A. Davis, 2007. Print.

2. Alfredson H, Pietila T, Jonsson P, et al. Heavy-load eccentric calf muscle training for the treatment of chronic Achilles tendinosis. Am J Sports Med 1998;26:360–6.

3. Visnes H, Hoksrud A, Cook J, et al. No effect of eccentric training on jumper’s knee in volleyball players during the competitive season: a randomized clinical trial. Clin J Sport Med 2005;15:227–34.

4. Kosek E, Ekholm J. Modulation of pressure pain thresholds during and following isometric contraction. Pain 1995;61:481–6.

5. Koltyn KF, Umeda M. Contralateral attenuation of pain after short-duration submaximal isometric exercise. J Pain 2007;8:887–92.

6. Rio E, Kidgell D, Purdam C, et al. Isometric exercise induces analgesia and reduces inhibition in patellar tendinopathy. British Journal of Sports Medicine. 2015;49(19):1277-1283. doi:10.1136/bjsports-2014-094386.

7. Rio E, Kidgell D, Moseley GL, et al. Tendon neuroplastic training: changing the way we think about tendon rehabilitation: a narrative review. British Journal of Sports Medicine.2015.

8. Rio E, van Ark M, Docking S, Moseley GL, Dawson K, Gaida J, van den Akker-Scheek I, Zwerver J, Cook J. Isometric Contractions Are More Analgesic Than Isotonic Contractions for Patellar Tendon Pain: An In-Season Randomized Clinical Trial. Clinical Journal of Sport Medicine. 2016.

Hip Pain: Return to Sport Considerations

Pre-arthritic hip pain is a common occurrence among athletes, especially those competing in ice hockey1 and field-based team sports (soccer, rugby, and football).2 While this area receives less attention than knee or shoulder injuries, current research is beginning to improve diagnosis and treatment of both intra-articular and extra-articular hip pathology. But, what about return to sport?

What the Literature Says

Determining an athlete’s readiness to return to sport is complicated. The decision with regards to hip pathology is even more convoluted due to the lack of evidence. Most literature discusses outcomes following arthroscopic surgery, and only a few studies outline the proposed benefit of conservative management.3

The available literature suggests that surgery for femoroacetabular impingement is beneficial in a symptomatic population, with 87% of patients returning to sport and 82% returning to previous level of competition.4 On the other hand, no randomized controlled studies adequately compare conservative and surgical management.5 Unfortunately, at this point the research tends to relate only to reported patient satisfaction, subjective questionnaires, and self-reported return to sport.6

How Do We Determine Return to Sport?

Unlike ACL reconstruction, hip injury lacks sufficient evidence to support return to sport guidelines. According to the 2016 Consensus Statement on Return to Sport, clinicians should combine information from a biological, psychological, and social standpoint.7 These factors include:

  • Health risk based on the athlete’s specific injury (subjective and objective measures)
  • Activity risk of returning to sport (type of sport, competition level, etc.)
  • Risk tolerance (pressure, fear of re-injury, etc.)

The StAART Framework (pictured below) proposed by Shrier and colleagues sums up this approach.8 It allows the clinician to comprehend and address all areas impacted by an individual’s readiness to return to sport.

MC020-205 Starrt Framework Chart_v03

Functional Testing Considerations

A recent systematic review conducted by Kivlan and colleagues demonstrated that several tests are reliable and valid when determining return to sport after hip injuries:9

  • Single-leg Stance
  • Deep Squat
  • Single-leg Squat
  • Star Excursion Balance Test (SEBT) / Y-Balance Test

These tests have appropriate validity and reliability but no solid cut-points, so findings should be interpreted on a patient-specific basis by considering their limb symmetry index during these tasks. Significant increase in medial–lateral sway and worse anterior–posterior control during a dynamic single-leg squat task in individuals with pre-arthric hip pain supports the use of a single-leg squat assessment.10

The modified star excursion balance test (also known as the Lower Quarter Y-Balance Test)  has been successful in identifying asymmetry and impaired proximal stability in many conditions. Recently, Johansson and colleagues performed the first study to determine the criterion and divergent validity of the SEBT in individuals with femoroacetabular impingement11. They determined that SEBT performance in the posterolateral and posteromedial directions had high to moderate criterion validity in relation to the HAGOS subscales for pain intensity and symptoms. Additionally, the posterolateral direction and ADL function showed high to moderate criterion validity. Finally and most importantly, the SEBT showed adequate divergent validity and could successfully differentiate between healthy individuals and individuals diagnosed with FAI.

Several recent studies have investigated if hop testing is appropriate in this population. Kivlan and colleagues evaluated the difference in hop testing (cross-over reach test, medial triple hop test, lateral triple hop test, and cross-over hop test) between the involved and uninvolved hip in dancers with hip pathology.12 All tests demonstrated excellent reliability (0.89 – 0.96); however, only the medial triple hop test showed significant difference between the two limbs with the non-involved limb achieving 17.8 cm more distance than the involved limb.

More recently, Kivlan and colleagues investigated the hop performance between dancers with clinically diagnosed femoroacetabular impingement and an asymptomatic control group. This study found a significant difference of approximately 50 cm when comparing the performance of the FAI group to the asymptomatic control group during both the medial triple hop test and the lateral triple hop test:13

table-remake

Further supporting the use of hop and dynamic balance activities, findings from another recent study determined that following arthroscopic hip surgery and concomitant rehabilitation, patients demonstrated > 90% limb symmetry index in the performance of a single-leg squat test, single-leg vertical jump, single-leg hop for distance, and single-leg side hop.14 While this information shows that we can achieve a LSI that is often used in return to sport of athletes post-ACL reconstruction, functional testing should be used with caution when translating it to a population of athletes with hip pain.

Continue with Caution

In the absence of definitive return to sport criteria, the clinician must focus on the tissue health (the load the tissue can absorb before injury), individual tissue stresses imposed by the athlete’s chosen sport and competition level, and any pertinent psychosocial factors (fear of re-injury).

Return to sport testing should be considered with caution as little evidence is available for this patient population.

References:

1. Lerebours F, Robertson W, Neri B, Schulz B, Youm T, Limpisvasti O. Prevalence of Cam-Type Morphology in Elite Ice Hockey Players. Am J Sports Med. 2016 Jan 28. pii: 0363546515624671. [Epub ahead of print]

2. Gerhardt MB, Romero AA, Silvers HJ, Harris DJ, Watanabe D, Mandelbaum BR. The Prevalence of Radiographic Hip Abnormalities in Elite Soccer Players. American Journal of Sports Medicine. 2012;40(3):584-588. doi:10.1177/0363546511432711.

3. Wall PD, Fernandez M, Griffin D, Foster N. Nonoperative Treatment for Femoroacetabular Impingement: A Systematic Review of the Literature. PMRJ. March 2013:1-9. doi:10.1016/j.pmrj.2013.02.005.

4. Casartelli NC, Leunig M, Maffiuletti NA, Bizzini M. Return to sport after hip surgery for femoroacetabular impingement: a systematic review. British Journal of Sports Medicine. 2015;49(12):819-824. doi:10.1136/bjsports-2014-094414.

5. Reiman MP, Thorborg K, Hölmich P. Femoroacetabular Impingement Surgery Is on the Rise—But What Is the Next Step? Journal of Orthopaedic & Sports Physical Therapy. 2016;46(6):406-408. doi:10.2519/jospt.2016.0605.

6. Sim Y, Horner NS, de SA D, Simunovic N, Karlsson J, Ayeni OR. Reporting of non-hip score outcomes following femoroacetabular impingement surgery: a systematic review. J Hip Preserv Surg. 2015;2(3):224-241. doi:10.1093/jhps/hnv048.

7. Ardern CL, Glasgow P, Schneiders A, et al. 2016 Consensus statement on return to sport from the First World Congress in Sports Physical Therapy, Bern. British Journal of Sports Medicine. May 2016. doi:10.1136/bjsports-2016-096278.

8. Shrier I. Strategic Assessment of Risk and Risk Tolerance (StARRT) framework for return-to-play decision-making. British Journal of Sports Medicine. 2015; 49: 1311–15.

9. Kivlan BR, Martin RL. Functional Performance Testing of the Hip in Athletes: A Systematic Review for Reliability and Validity. International Journal of Sports Physical Therapy. 2012;7(4):402-412.

10. Freke MD, Kemp J, svege I, Risberg MA, Semciw A, Crossley KM. Physical impairments in symptomatic femoroacetabular impingement: a systematic review of the evidence. British Journal of Sports Medicine. June 2016. doi:10.1136/bjsports-2016-096152.

11. Johnansson AC, et al. The Star Excursion Balance Test: Criterion and divergent validity on patients with femoral acetabular impingement. Manual Therapy. 2016; 26(C): 104-109. doi:10.1016/j.math.2016.07.015.

12. Kivlan BR, Carcia CR, Clemente FR, Phelps AL, Martin RL. Reliability and validity of functional performance tests in dancers with hip dysfunction. International Journal of Sports Physical Therapy. 2013 Aug;8(4):360-9.

13. Kivlan BR, et al. Comparison of Range of Motion, Strength, and Hop Test Performance of dancers with and without a Clinical Diagnosis of Femoroacetabular Impingement. International Journal of Sports Physical Therapy. 2016; 11(4): 527-535.

14. Tijssen M, van Cingel R, de Visser E, Sanden der MN-V. A clinical observational study on patient-reported outcomes, hip functional performance and return to sports activities in hip arthroscopy patients. Physical Therapy in Sport. 2016;20(C):45-55. doi:10.1016/j.ptsp.2015.12.004.

Evidence-Based Strength Training: Gluteus Maximus

To build upon my previous post regarding Evidence-based Strength Training of the Gluteus Medius, I wrote the following article for MedBridge Education

Pain and Gluteal Strength

The gluteal musculature has been implicated in many different pathologies due to its potential impact on lower extremity biomechanics. During weight bearing, the femur moves about a fixed patella and therefore excessive femoral internal rotation and adduction results in increased contact directed primarily at the lateral facet of the patella1. Just 10° of IR can lead to a substantial decrease in PFJ contract area and a 50% increase in joint stress. Coinciding with these findings, Souza et al.2 found that females with patellofemoral pain syndrome (PFPS) demonstrated greater peak hip internal rotation compared to the control group during running, drop jump, and step down. The PFPS group also demonstrated 14% weaker hip abductor strength and 17% weaker hip extensor strength. Wilson et al3, Noehren et al4, and Nakagawa et al5 found that individuals presenting with PFPS demonstrated increased hip adduction during running, jumping, and single-leg squats. This excess femoral adduction creates an increased valgus force about the knee joint, which in turn causes increased loading of the lateral patellofemoral joint. In addition to patellofemoral pain, a hip etiology or influence has also been implicated in iliotibial band syndrome6, anterior cruciate ligament rupture7, and achilles tendinopathy8. More specifically, impaired gluteus maximus function has been demonstrated in individuals diagnosed with femoroacetabular impingement9.

Gluteal strengthening and Rehabilitation

In support of a gluteal etiology, several studies have found the effectiveness of gluteal strengthening in the treatment of lower extremity disorders. A recent systematic review conducted by Santos and colleagues9 found gluteal strengthening decreased the highest intensity of pain experienced during the previous week, pain when ascending and descending stairs, and pain while squatting or sitting for prolonged periods amongst individuals diagnosed with PFPS. Additionally, with regards to rehabilitation following anterior cruciate ligament reconstruction, the inclusion of hip strengthening appears to improve sagittal plane dynamic balance at three months post ACLR as compared to traditional rehabilitation10.

EMG Activity and Exercise Goals

According to Reiman et al.11 and Escamilla et al.12, moderate electromyographic activity (EMG) activation (21-40% MVIC) is best used to facilitate endurance and neuromuscular re-education; high activation (41-60+% MVIC) in order to promote strength gains.

From Biomechanics to Exercises

Gluteus Maximus

Origin: Ilium posterior to posterior gluteal line; dorsal surface of sacrum and coccyx; sacrotuberous ligament

Insertion: Iliotibial tract and gluteal tuberosity

Primary Function: Extends thigh and assists in hip abduction and external rotation; steadies thigh and assists in rising from sitting position

Among introductory exercises, the gluteus maximus achieves the highest EMG levels during:

  1. Front-plank with Hip Extension
  2. Gluteal Squeeze
  3. Side-plank with Hip Abduction
  4. Quadruped with Contralateral Arm/Leg Lift
  5. Uni-lateral Bridge

screen-shot-2016-09-19-at-2-51-18-pm

Additionally, you must consider the interaction of other muscles acting with or against the gluteus maximus when determining exercise prescription. It has been proposed that individuals who demonstrate excess femoral internal rotation during functional tasks may be relying too heavily on the tensor fasciae latae to control their pelvis in the presence of weak or inhibited gluteus medius musculature.

Selkowitz and colleagues determined that the following exercises achieved the best Gluteal to Tensor Fasciae Latae Activation Ratio:

  1. Clamshell
  2. Side-step with resistance band
  3. Single-leg bridge
  4. Quadruped hip extension with knee extended
  5. Quadruped hip extension with knee flexed

screen-shot-2016-09-19-at-2-55-12-pm

Finally, when progressing your patient towards more functional closed kinetic chain and sport/activity-specific exercises, the following exercises achieve the highest gluteus medius activation:

  1. Cross-over Step-up
  2. Hip Thrust Variations (Barbell, Band, American)
  3. Rotational Single-Leg Squat
  4. Skater Squat
  5. Single-Leg Squat

screen-shot-2016-09-19-at-2-56-43-pm

Exercise prescription is a multi-faceted decision, which is driven by the individual patient’s goals, functional limitations, and the evidence supporting the treatment of these factors. Using EMG studies to drive the selection of exercise is highly valuable, especially during early stages of rehabilitation or when attempting to isolate individual muscles and/or groups of muscles. However, there are limitations when comparing different studies due to methodological differences (type of EMG, patient population, data analysis, etc.). Additionally, due to the cost and time to conduct these studies, there are thousands of exercises that have not been evaluated in the literature. In light of this information, these studies should be used to guide your decision making, it should not override your clinical expertise when accompanied by biological plausibility.

VMO: An Update

The following is an article written for the online, video-based physical therapy continuing education company MedBridge

Patellofemoral pain syndrome (PFPS) is among the most common sports injuries and yet the current treatment protocols are not optimal. In particular, the latest research questions our ability to selectively recruit vastus medialis obliquus (VMO) and affect its timing and suggests that VMO may have nothing to do with the PFPS.

Prevalence of Patellofemoral Pain Syndrome

PFPS has an astounding prevalence according to a retrospective case-control analysis by Taunton et al. They analyzed 2,002 running-related injuries seen at a primary care sports injury facility – and 42.1% (842/2,002) were knee injuries. Of these knee injuries, 39.3% (331/842) were due to patellofemoral pain syndrome (PFPS), which made PFPS by far the most common diagnosis found in this large-scale study.

Similarly, in an older study (1984), Devereaux et al found that over a five year period, 137 patients presented with PFPS – accounting for 25% of all knee injuries seen at this sports injury clinic.

These two studies were conducted 17 years apart, giving support to the consistently high prevalence of this disorder. Now the most important question is, how are we treating these patients?

How are we treating patients with PFPS?

Imbalance of LV and VMO

The biomechanical study by Lieb et al made the VMO the mainstay of most physical therapy protocols and treatment approaches for PFPS.

Conducted in 1968, the study found that VMO’s fibers are oriented at 55° from the longitudinal axis of the femur. This orientation alone makes VMO the primary restraint to lateral subluxation of the patella. The study further postulated that VMO was able to counterballance the pull of the much larger vastus lateralis (VL) due to the discrepancy in mechanical advantages.

As a result of this study, an insufficient balance between the VL and VMO has long been considered the primary contributing factor in developing patellar subluxation, or maltracking.

VL:VMO timing

A study by Cowan et al found that subjects with PFPS have an imbalance of VL:VMO timing. The VL typically begins to fire approximately 15-20 ms prior to the VMO.

Due to this understanding of the biomechanics, the treatment strategy typically involved correcting the potential VMO atrophy, hypoplasia, inhibition, and impaired motor control.

Now, this all seems logical in theory, but can we actually selectively train the VMO? Is this relatively small muscle affected differently than the rest of the quadriceps musculature in the presence of pain?

New research questions…

Does VMO atrophy relative to the rest of quadriceps?

A recent study by Giles and colleagues refutes one of the cornerstones of the VMO theory; namely, that this small muscle tends to atrophy relative to the rest of the quadriceps during or following surgery. They performed a cross-sectional study of 35 participants diagnosed with PFPS.

The results showed atrophy of all portions of the quadriceps muscles – and no selective atrophy of the VMO – present in the affected limb of people with unilateral PFPS.

Can we selectively activate VMO?

Even if the atrophy was present, the literature is not very kind to the ability to preferentially activate this musculature either.

Cerny et al evaluated the ability to preferentially recruit the VMO during 22 different quadriceps exercises. Through electromyographic analysis, they determined that VMO activity was not higher in any exercise compared to VL.

In a randomized controlled trial, Song et al found no evidence that VMO can be activated separately. They compared the change in VMO cross-sectional area after 8 weeks of unilateral leg press and unilateral leg press with subsequent hip adduction. The two groups showed no significant difference between the change in VMO cross-sectional area (the standard leg press actually yielded better results).

Thus, selective isolation of the VMO in everyday clinical practice is highly unlikely. In all reality, if we consider inability to selectively recruit their target, most of the ‘VMO programs’ are merely strengthening the quadripceps as a whole. If we could selectively recruit these fibers, according to Grabiner et al, it would take approximately 60% of maximal voluntary contraction to stimulate hypertrophy of the VMO.

Does VMO training have advantages over general quadriceps strengthening?

In 2010, Bennell et al investigated how VMO retraining compares to a general quadriceps strengthening program in relation to vasti onset.

The VMO retraining group used EMG biofeedback during the following series of exercises:

  • isometric VMO contractions at 90° of knee flexion
  • standing mini squats to 40°
  • isometric contraction of the VMO in combination with hip abduction and hip external rotation during an isometric wall contraction in standing
  • step downs

The quadriceps group performed:

  • isometric quad sets
  • straight-leg raises
  • SAQs
  • side-lying hip abduction

At the conclusion of the training programs, the retraining group actually did create more significant changes in stair descent activation in the short-term. However, at the 8-week follow-up, both values were nearly identical. The initial improvement may have been due to the use of ‘step downs’ in the retraining group, which most closely simulates the functional and muscular demands of stair descent.

During stair ascent, on the other hand, the quadriceps strengthening group caused a much more significant alteration in VMO:VL timing and was the only group that caused the VMO to fire prior to the VL.

A study conducted by Laprade et al showed similar results using isometric exercise. This study compared the EMG activity in individuals with PFPS and asymptomatic controls during 5 isometric exercises. There was no significant difference in the ratio of VMO:VL firing between the two groups.

Given these results, I find it hard to support the use of VMO training in everyday clinical practice.

Does VMO strengthening make a difference for PFPS?

Suppose it was possible to selectively recruit the VMO. Would it reduce patellofemoral contact stress sufficiently to relieve the pain?

Sawatsky et al say no. They conducted a biomechanical study using New Zealand white rabbits. Although this is not a direct human study, the muscular alignment and pull of the quadriceps is very similar: the fibers of the VMO and VL are oriented at 45-50° and 14-19°, respectively, in relation to the longitudinal axis of the femur.

They transected VMO at varying levels of knee flexion (30°, 60°, and 90°), measuring patellofemoral joint contact pressures before and after the transections.

There were no significant differences between peak pressures, average pressures, contact areas, or contact shapes before and after transection.

If the contact area and pressure are not altered when the muscle is removed from the equation, then why do we continue thinking VMO training is the gold standard in PFPS treatment?