Injury Prevention in Netball

With Netball taking over as the main focus sport next term within the School I work, I felt it necessary to make a review of the current literature regarding injury prevention in Netball players

Proactive or reactive

Netball involves rapid acceleration, deceleration, and directional changes which place considerable forces through articular and periarticular structures, similar to other field and court sports ¹. A high rate of overuse injuries occur among both elite and amateur players; lower back, ankle, knee and the shoulder are sites of the most consistent injuries, with injuries from the lower limbs coming from repeated impacts with hard surfaces during landing, hopping and, to a lesser degree, when pivoting. Young people especially are at particular risk of sports injury because of high levels of exposure at a time of major physiological change ². Although fewer lower-limb injuries occur in junior players ³, incidence of injuries from falls at 35% suggests that such injuries could be due to poor balance or a lack of other key movement skills ⁴.

It is important therefore to understand the frequency and nature of sports injuries at the youth level to assist in the development of effective injury prevention strategies. Once again the role of any Strength & Conditioning/athletic development coach is to get the athlete fit and ready to take the field of play.

Even national squad multi-disciplined teams have confessed to being reactive rather than proactive with regards to the injury prevention/strength & conditioning programme of its Netball structure ⁵. Previous attempts of being proactive include the use of ankle or knee guards but without a detailed strength and conditioning programme alongside; this shows a lazy approach to injury prevention. The evidence is uncertain regarding the use of knee braces, although there is some evidence from cadaver studies that knee bracing does offer protection to knee ligaments under external load ⁶. This effect may not carry over to the high-velocity, multidirectional forces encountered during sporting activity, such as Netball. What is becoming clear is that there is significant and consistent evidence in the literature to support the use of injury-prevention strategies in adolescents that include preseason conditioning as well as functional training, education, strength and balance programmes that are continued throughout the playing season ⁷.

Screening

The effects of screening players, both before and throughout the season has several advantages; highlighting injury risk of players, physiological imbalances and the progress of fitness development. In addition, the act of screening players can develop self-evaluation/awareness of their own anatomy, body mechanics and the purpose of specific aspects of their training.

Upon working with a handful of Netball players this term; some were unable to control a basic lunge or squat movement under body weight conditions, yet were loading these movements in a gym situation. This caused compensation strategies and accentuated stress on areas of relative flexibility, where injuries appeared. By screening these elements separately, it is possible to demonstrate to players and coaching personal the reasons for these problems, as well as laying foundations for the changes that would be necessary to overcome them. An example of a progressive screening could be: Single leg balance-single leg squat-dynamic hopping with turning in the air. This example looks to screen for possible knee ligament tear/sprains of which are consistent with an inability to counterbalance external torque/rotation when landing or pivoting.

Hypermobility

Hypermobility or generalised joint laxity is defined as a condition in which most of an individual’s synovial joints have a range of motion beyond normal limits. The prevalence of hypermobility in schoolchildren has been estimated to be 13–27%⁸, with a higher prevalence in girls than boys ⁹. In some sports, hypermobile joints may be associated with a performance advantage—for example, spin bowlers in cricket, gymnasts, and ballerinas. However, previous studies have revealed an increased incidence of musculoskeletal complaints such as arthralgias, joint subluxations, joint dislocations, and sprains in sportsmen with hypermobile joints ¹⁰.

Hypermobility in the knee joint-a risk factor for potential knee ligament injuries

The Beighton index gives an overall composite score of 0–9 with regards to joint hypermobility and can also be categorised into three groups: 0–2 (not hypermobile); 3–4 (moderately hypermobile); 5–9 (distinctly hypermobile) ¹¹. Not surprising that the indices of injury rates increase alongside the increase in the Beighton index. But researchers still argue whether this is a cause or effect scenario due to the cross sectional method of most of the research. What seems to be more conclusive is that patients with hypermobility syndrome have been shown to have impaired joint proprioception in both the knee and finger joints ¹². This impaired proprioception may not just account for an increase in acute injuries, but may also explain the increased incidence of secondary degenerative osteoarthritis seen in hypermobile joints ¹³.

Risk factors for Netball related injuries

Not warming up before a game. A simple precaution but still not adhered to by some coaches. One study found that only 60% of netballers reported warming up before training and the game! Previous studies have shown that the range of movement of a joint can be different before and after a warm up ¹⁴. This is very important when you consider the amount of joint related injuries in Netball. Participants who reported training for at least 4 h/week had significantly fewer injures than those who trained for <4 h/week ¹⁵. However, it should be noted that the quality of training should always outweigh the quantity of it.

Although disagreement still surrounds the most effective warm up for Netball, and indeed most sports, I have included some necessary key points when designing any warm up:

-           Make it fun

-           Include multi directional changes of direction

-           Provide an environment for players to develop decision making-don’t just go through the routine

-           Mimic the sport to a degree in the warm up; if you’re preparing for a rugby game-contact has to be essential. Cricket = catching and throwing the ball from a variety of different body positions

Conclusion

Injury prevention strategies should seek to reduce the incidence of common injuries in netball by gaining and understanding the mechanisms associated with each of these injuries. Training programs should be specific to netball and focus on demands of the games. Skills and movement patterns of individual positions during game play should form the basis of these programs. All injury prevention programs, resources and strategies should be produced in formats that encourage coaches and players from all levels of competition to take them up. It may also be appropriate to investigate if injury prevention models that have proven effective in other sports could be extrapolated to netball. Lastly, education, both from a coach and player perspective, is vital if injury prevention programmes are going to be successful in the long term.

References

1.      Smith, R., Damodaran, A. K., Swaminathan, S., Campbell, R., Barnsley, L. (2005). Hypermobility and sports injuries in junior netball players. British Journal of Sports Medicine, 39(9), 628–631.

2.      Lidqvist, K. S., Timpka, T., Bjurulf, P. (1996) Injuries during leisure physical activity in a Swedish municipality. Scandinavian Journal of Social Medicine, 24, 282–92.

3.      Finch, C., Valuri, G., Ozanne-Smith, J. (1998). Sport and active recreation injuries in Australia: evidence from emergency department presentations. British Journal of Sports Medicine, 32(3), 220–225.

4.       Routley, V. (1991).Sports injuries in children-the five most commonly presented sports. Hazard, 9,1–8.

5.      Elphinstona, J & Hardman, S. L. (2006). Effect of an integrated functional stability program on injury rates in an international netball squad. Journal of Science and Medicine in Sport, 9(1), 169—176.

6.      Paulos, L. E., Cawley, P. W., France, E. P. (1991). Impact biomechanics of lateral knee bracing. The anterior cruciate ligament. American Journal of Sports Medicine, 19(4), 337–342.

7.      Abernethy, L., & Bleakley, C. (2007). Strategies to prevent injury in adolescent sport: a systematic review.  British Journal of Sports Medicine, 41(10), 627–638.

8.      Van der Giessen, L. J., Liekins, D., Rutgers, K. J. (2001). Validation of Beighton score and prevalence of connective tissue signs in 773 Dutch children. The Journal of Rheumatology, 28, 2726–2730.

9.      Larsson, L. G., Baum, J., Mudholkar, G. S. (1987). Hypermobility: features and differential incidence between the sexes. Arthritis & Rheumatism, 30(12), 1426–1430.

10.  Finsterbush, A., Pogrund, H. (1982). The hypermobility syndrome: musculoskeletal complaints in 100 consecutive cases of generalized joint hypermobility. Clinical Orthopaedics and Related Research, 168, 124–127.

11.   Boyle, K. L., Witt, P., Riegger-Krugh, C. (2003). Intra-rater and inter-rater reliability of the Beighton and Horan joint mobility index. Journal of Athletic Training, 38(4), 281–285.

12.  Hall, M. G., Ferrell, W. R., Sturrock, R. D., et al. (1995). The effect of the hypermobility syndrome on knee joint proprioception. British Journal of Rheumatology, 34(2), 121–125.

13.  Jonsson, H., Valtysdottir, S. T., Kjartansson, O., et al. (1996). Hypermobility associated with osteoarthritis of the thumb base: a clinical and radiological subset of a hand osteoarthritis. Annals of the Rheumatic Diseases, 55, 540–543.

14.  Bird, H. A. (2004). Rheumatological aspects of dance. The Journal of Rheumatology, 31, 12–13.

15.  McManus, A., Stevenson, M. R., & Finch, C.F. (2006). Incidence and risk factors for injury in non-elite netball. Journal of Science and Medicine in Sport, 9(1-2), 119—124.

Is It Bad For Females To Do Press Ups?

This blog is in response to a question I was asked recently by a girl at Bloxham School; ‘‘I have heard press ups can affect a women’s ability to have baby’s’’.

This is a hardly surprising question due to the way gyms market fitness for females; the majority are encouraged to stay away from the dumbbells and instead are pushed into pilates, spin classes or ‘’core stability’’ workshops! However, this will not prepare the young female athlete for an enjoyable and perhaps successful journey in sport. Strength & Conditioning/athletic development coaches should be encouraging basic bodyweight strength exercises from a young age, especially for female athletes. 

Why should female athletes invest more time in Resistance Training?

There are certain characteristics within the female physiological make up which make them more prone to injury while playing competitive sport:

Hormones: During puberty the production of estrogen in girls increases fat deposition and breast development, whereas testosterone production in boys increases bone formation and protein synthesis. Though estrogen also stimulates bone growth, boys have a longer growth period, and therefore adult men tend to achieve greater stature than adult women. Resistance training can stimulate the synthesis of growth hormone in female athletes, which aids protein synthesis.

Joint laxity: Some females have too much movement in their joints. Resistance training looks to develop key stabilising muscles around the joints.

Lower limb alignment: 

This image shows the Q angle; this is the angle formed by a line drawn from the ASIS to central patella and a second line drawn from central patella to tibial tubercle. An increased Q angle is a risk factor for patellar subluxation, while the average Q angle is 14 deg for males and 17 deg for females. Strengthening the lower limb muscles, especially the vastus medialis obliquus, can help increase the stability of the knee joint in women.

Muscle strength: When expressing strength relative to body weight, the lower body strength of women is similar to that of men, while the upper body strength of women is still somewhat less.

Ligament size: A growing amount of research has shown that females on average have smaller ligament widths when compared to male athletes. It has been speculated that smaller Anterior Cruciate Ligaments (ACL) may predispose females to ACL ruptures. Resistance training has been shown to increase the size and strength of tendons and ligaments, especially in the lower limbs. This takes on even more importance when you consider female athletes are known to be 6 times more likely of injuring their ACL while participating in competitive sports.

But how does this impact on sport?

Apart from the above physiological improvements, the number one factor that strength training achieves is the ability to get the athlete onto the field of play. Staying fit and injury free has to be the main aim for any Strength & Conditioning/Athletic development coach. Strength training, if done correctly can enhance an athlete’s durability. As well as this, many sports which involve contact with the floor and falling over require sufficient levels of strength just in order to prevent upper body limb injuries from occurring.

‘‘I have heard press ups can affect a women’s ability to have baby’s’’

In conclusion, and in response to the above question, even during pregnancy resistance training is recommend to help keep mum and baby fit; as long as the load is light to moderate and the emphasis is on muscular endurance (12-15 reps). Luckily, these types of questions are few and far between at Bloxham and slowly we are starting to change the culture surrounding resistance training and its role with female athletes.

What is Dynamic Correspondence?

Here is a guest blog I wrote for Excelsior Sports performance investigating the term ''Dynamic Correspondence''.

http://www.excelsiorgroup.co.uk/blog/what-dynamic-correspondence