Musculo-skeletal   [back to the Category]

Spinal stress fractures.   [read the french version]

Author :   Docteur Anne Thiescé

Spinal stress fractures are common and affect the spinal isthmi, posterior articulations and pedicles.
Dancers begin practising their art at an early age and many devote themselves to intensive training throughout their growth years. Furthermore, dancers have not usually finished growing, when, from the moment they enter a company, they have to perform numerous "portés". This is a time when there is a risk of spondylolysis and spondylolisthesis appearing, possibly due to a lack of flexibility which results in a difference between the osseous and the musculo-tendinous growths: an imbalance which is often overlooked in ballet.
Common aetiological factors of stress fractures of the L5 isthmus, Fig 1, in addition to the morphological anomalies of the lombosacral hinges, are: stress during compression and shearing movements, muscular imbalance of the trunk flexors - extensors, the hyperlordosis required to compensate the lack of turn out by a lower limb or to carry out certain choreographic gestures, the retraction mainly of the psoas, the hardness of certain floors, the repeating of badly performed "portés" and during the growth of disharmonious musculature.
Isthmoid fractures affect 20% of dancers and usually occur between the ages of 9 and 15. They are usually localised on L5, but can be multiple and occur at superior lumbar levels. Fig 2,3,4. The discovery of an isthmoid lysis or a spondylolisthesis does not mean that ballet must be stopped as long as L5 does not slide over S1 by more than 40% (spondylolisthesis in stages 1 or 2). Fig 5.
When diagnosis is early, treatment lies in the dancer wearing a corset for at least a month. Ballet can then be resumed progressively with a lumbar belt, coupled with a suitable re-education. This lumbar belt can be worn later on for practising new "portés" or new choreography.
When diagnosis is delayed and the stage of chronic stubborn pains is reached, a symptomatic treatment is necessary. Dancers must wear a lumbar belt when they feel pain and, after an appropriate re-education, follow a personalised daily exercise programme which will usually allow them to continue dancing.

Bibliography:
Pelletier A., Spondylolisthésis, Médecine et Sciences de la danse. IVe congrès international. 18/6/94.
Sabourin F., Pathologie rachidienne microtraumatique et danse. Médecine des Arts 1996 N°15 p37-40.
Thiescé A., Le geste dansé et ses conséquences en rhumatologie. Ed Laboratoires Ciba-Geigy 1996.