Lower trunk injuries follow a predictable pattern among dancers unless they are properly treated. Sean Fyfe explains.
Dancers with lumbopelvic/hip dysfunctions are incredibly challenging for sports injury professionals to diagnose and treat. What follows is derived from my own recent experience of working with both ballet and contemporary dancers, drawing together some of what I have learned about their diagnosis and treatment.
Two important points must be made right at the start. Firstly, the lumbar spine, pelvis and hip should never be considered separately: a complex interplay exists between them. Subtle changes or inadequacies in one area will have a definite impact on the surrounding areas. The sports therapist’s assessment and management needs to reflect an appreciation of this.
Secondly, you will need to focus less on identifying painful structures and more on the mechanical dysfunction, which requires you to have a thorough understanding of the function of the lumbopelvic hip complex. And we are not just talking here about ‘normal’ function as it applies to the general population, but normal for dancers, which is considerably different in terms of range of movement and muscle control.
Of course, mechanical dysfunction will often, over time, lead to a more serious structural pathology. A prime example is spondylolysis and spondylolisthesis, a common injury in dancers. You should always seek to exclude these pathologies; and if they are present take appropriate action. Before the patient returns to dancing, however, the underlying mechanical dysfunction must be corrected.
Let’s look at two aspects of the movements that dancers perform, as a way of illustrating why they commonly present with specific muscle imbalances.
Unusually, dancers (and, indeed, gymnasts) perform repetitive open-chain movements with their lower limbs. Most sports follow a more natural movement pattern, with the lower limb undertaking closed chain, while the upper limb is reserved for the open-chain movements. These open-chain lower-limb movements require a high level of dynamic control through the whole lumbopelvic hip complex.
Take, for instance, the ‘grand battement’ (high kick) move (see diagram 1). The dancer begins in turnout and must hold the stance leg in turnout. The other leg is then flexed and abducted while keeping the knee straight. The muscle work should be:
This action faces the acetabulum (hip socket) in a cephalad direction (upwards) to clear the acetabular rim from the glenoid. The posterior rotation must take place without flexion of the thoracic spine so that the dancer maintains good trunk posture. The posterior rotating pelvis imparts flexion on the lumbar spine. The segmental stabilisers of the lumbar spine need to be active to prevent shear forces between segments.
In dance, lumbar spine movement is biased towards extension. In standing, dancers are trained to stand in anterior tilt, which imparts extension on the lumbar spine, and most dance choreography involves a lot of extension-based movements. One such is the ‘backward bridge’ . For this movement it is important that there is flexibility through the whole system: hip extension, range of posterior tilt of the pelvis relative to the hips and extension of the lumbar and thoracic spine. The danger is that excessive movement takes place at a segment in the lower lumbar spine because of a lack of stabilisation and/or poor mobility in other areas of the chain.
|Overactive and tight areas||Underactive and weak areas|
|Lumbar spine extensors (quadratus lumborum, erector spinae)||Gluteus maximus|
|Hip flexors (iliopsoas, TFL)||Rectus abdominis|
|Deep external rotators of the hip (piriformis, obturators internus and externus, quadratus femoris, inferior and superior gemellus)||Obliques, internal and external|
|Deep segmental stabilisers|
It is the repetition of these types of movements that over time can lead to imbalances. Table 1 (above) summarises an overview of the muscle imbalances typically seen in a dancer suffering with injury in the lumbopelvic hip complex. Bear in mind that the definition of ‘weak’ in a dancer may be relatively strong in the average population.
These muscle imbalances may lead to arthrokinematic changes (the way adjoining joint surfaces move against each other) as listed in Table 2 (below); these should all be considered during the therapist’s assessment and management.
So we can begin to see how we would expect a dancer to change during years of training and performing. At a young age, muscle imbalances start to develop. At first, any joint restrictions will be mainly related to muscle overactivity. Over time these soft tissue restrictions lead to changes in joint surface relationships. Incorrect movement of the joints, such as lumbar spine instability or impingement of the hip joint, then lead to structural changes of joint surfaces, bone or discs. Chronic joint restrictions will promote capsular adaptations which can further affect joint movement.
|Nature of arthrokinematic change||Reason|
|Anterior femoral head displacement with associated restriction to hip flexion with adduction and decreased internal rotation||Increased tone through external rotators causes an anterior position of the femoral head in the acetabulum (the same mechanism that is often seen in the shoulder of the overhead athlete, where increased tone in infraspinatus and teres minor cause the humeral head to shift in the glenoid)|
|Reduced lumbar flexion||Overactivity of the lumbar spine extensors restricts the movement into flexion. This can be deceptive because dancers have such a large range of movement when bending forward from a standing position; but the actual range of lumbar flexion is often poor|
|Hypomobility of thoracolumbar junction and lower thoracic spine||The overactivity of the lumbar extensors and psoas, which attach in this region, increases joint compression, limiting mobility|
|Reduced hip extension||Overactivity and tightness of hip flexors|
|Increased abduction, decreased adduction||Tightness through ITB/TFL and posterior rotators, limiting adduction|
And the downward spiral can continue. Prevention from a young age is critical to reduce the consequences of injury later in an athlete’s or dancer’s career. As I have stated in previous SIB articles, this is where I believe support practitioners can make the biggest impact, working with organisations to adjust training programmes so that from a young age athletes and dancers develop their bodies free from destructive imbalances, rather than just learning their sport or dance.
When I began working with dancers in the UK – professionals, students, contemporary and ballet – I was alarmed at how little time they devoted to training away from dancing. It is apparently normal for a full-time programme to be very largely dance, with a little pilates (which in most cases is non-specific) and some stretching. It is not uncommon to be dancing for six hours a day and doing nothing else.
The injury rates being sustained are very high. A German study (1) from 2003 found that among 77 professional ballet dancers, 88% suffered from discomfort in the lumbar spine. In an earlier Swedish study (2), researchers at Lund University found that among 128 professional ballet dancers 70% reported low back problems within the previous 12 months.
These rates are far in excess of other sports I have worked with. Dancing alone doesn’t ensure abdominal strength, good activation through glut max or activation of segmental stabilisers. In that respect, dance is no different from any other sport: its performers have to put aside the time to do specific body maintenance, in conjunction with regular screening, to give themselves the best chance of remaining injury free.
Sean Fyfe is a physiotherapist working with Metis Physio Centres in London, a multi-disciplinary clinic. He works with elite dancers and theatre performers
Illustrations by Viv Mullett