ISSUES OF MICROINSTABILITY OF COXA IN PROFESSIONAL CLASSICAL BALLET DANCERS

Abstract

Starting point: There is a wide range of mobility in the hip joint, which can be defined as ranging from reduced range of motion in any of the SFTR planes, to standard ranges of motion, to laxity (asymptomatic hypermobility), to instability (symptomatic hypermobility). Microinstability of the hip often refers to small, subtle disturbances in the stability of joint structures.

Group: The test group consisted of 68 professional dancers of the Slovak National Theatre classical ballet who fulfilled the predefined selection criteria.

Methods: A clinical study is presented in which the clinical testing by HEER, AB-HEER and Prone instability test was used in professional dancers of the classical ballet of the Slovak National Theatre in order to identify the presence of microinstability of the hip joint, to assess the influence of gender and dominance of the dancer's side of the body on the presence of this diagnosis.

Results: Testing confirmed the presence of hip microinstability with a very high incidence of 76.9%. More detailed analyses revealed that microinstability was more pronounced in the female gender, with a confirmed difference between males and females (females 90.6% vs. males 63.6%, p<0.01). The difference in the side on which microinstability was detected was not statistically significant between genders. Similarly, there was no difference in the presence of microinstability and the side of its localization in the groups with different dancer dominant side. These findings, in addition to the high incidence of microinstability, point to significant differences between the sexes.

Conclusions: The prevalence of hip and groin injuries is high in ballet dancers. These injuries can result in long-term disability, reduced quality of life and, in some cases, premature career termination. Microinstability is a harbinger of possible severe hip joint damage, so this issue should be given sufficient attention in professional classical ballet dancers.  It is also extremely important to conduct research specifically targeted at this specific group of professionals. The general aim is to achieve faster and more effective rehabilitation, thus minimising the negative impact on dancers' careers. In the tested group of dancers, the positive result for the presence of microinstability was found based on the positive result of all three tests at 76.9%, indicating a high prevalence of occurrence. A higher prevalence was observed in the female group, with a prevalence of microinstability at the right hip joint, but without significance. A relationship was found between gender and the Prone instability test score as well as the presence of microinstability, but the relationship between the dancer's dominant side and microinstability on each side was not confirmed.