By: Gary Delahunt, ESPH Clinic Manager
If you came to our clinic looking for a concise, robust and reliable way to prevent serious knee injury such as an Anterior Cruciate Ligament (ACL) rupture, and you were told to start doing ballet, would you?
OK, maybe not all the components of ballet, the Tutus and Leotards are optional! But, there is a side of ballet that that seems to be vastly reducing the incidence of ACL ruptures in both men and women.
What is the ACL?
The anterior cruciate ligament is one of a pair of ligaments that criss-cross inside to the knee. Its role is to add stability to the knee, in particular to resist: hyper-extension, the tibia slipping forward on the femur and to limit the internal rotation of the tibia on the femur. The ACL is designed to handle large forces. If, however, the knee experiences a force of large enough magnitude (a slip, trip, fall, jump, landing, change of direction) and the muscles are not sufficiently strong enough to absorb the force, then the ligament may tear. It is one of the most common ligament injuries in sport, accounting for up to 50% of the documented ligamentous knee injuries.
Treatment for ACL rupture commonly requires surgical intervention. This can be a costly procedure, both in time and money. From the point of referral to a full return to sporting activities, treatment and rehabilitation can take up to two years, and these are just the short-term implications. Some studies have suggested that ACL rupture is also associated with an increased risk of early-onset knee osteoarthritis.
Up to 70% of all ACL injuries occur during non-contact incidents. In team ball sports, the incidence of ACL injuries can be as high as 8%, whereas in ballet the incidence is around 0.2%.
There have been many proposed reasons offered as to why someone might suffer an ACL tear, including:
- Type of footwear
- Hip to knee angle
- Weak leg muscles
- Reduced ankle range of movement
- Hormonal changes
In 2015, I attended a workshop seminar held by the Royal London Ballet medical team. Their clinical lead, physiotherapist Greg Retter, had been with the team for a couple of years by then and has a background in sports science. The medical team have been measuring the various parameters (hip control, knee balance etc.) of the dancers in order to profile their strengths and weaknesses and hence get a better understanding as to why some people get injured and others don’t.
One of the proposed benefits of ballet dancing suggested by Retter and his team in relation to ACL incidence is the volume of jumping and landing practice to which ballet dancers are exposed to. Dancers perform more than 200 jumps per 90 minutes, many of which involve single-leg landing.
Ballet helps with leg strength, balance, trunk stability, hip control, jump/landing practice, and it is these aspects of jumping and landing that can be isolated for focused treatment in order to limit the risk of serious ACL injury.
Many studies have shown that supervised jump and balance training programmes that are progressive in difficulty and focus on neutral alignment can dramatically limit ACL injury rates.
Physiotherapists are trained to break down movements such as jumping, running, landing, twisting, pushing, and pulling etc. into their many components. It is by doing this that muscle weakness and imbalance, joint instability, and movement dysfunction can be identified. A tailored focus can then be applied to an individual’s specific prehabilitation and rehabilitation needs, in order to limit the risk of a potentially devastating ACL injury.