Research: Hallux Valgus in Dancers

This review article discusses the relevant anatomy and clinical presentation of hallux valgus with a specific focus on the condition in dancers. There are many intrinsic and extrinsic risk factors for hallux valgus in the current literature, including age, gender, genetics, race, first ray hypermobility, foot architecture, tight Achilles tendon complex, first metatarsal length, footwear, technique, and workload/stresses on the MTP joint.

Research: A Preseason Cardiorespiratory Profile of Professional Dancers

Nine professional dance companies which regularly perform the post-hire, pre-season health screen for professional dancers (developed by the Dance/USA Task Force on Dancer Health) were examined for this study. Examining several indicators of physical fitness, the researchers sought to identify a cardiorespiratory fitness profile of professional dancers, look for differences in heart rate of modern and ballet dancers during and after a fitness test, and identify any genre- or company-specific variables that may be related to level of fitness among professional dancers.

Research: Dance-related Concussion: A Case Series

While concussions have been a focus for sports medicine literature and the sports media, they have received very little attention in the dance and dance medicine communities. This case series retrospectively reviewed the medical charts of 11 dancers who suffered a concussion during dance activities over the course of 5.5 years. The cases presented here are similar to sports-related concussion cases in mechanism of injury and presentation of symptoms. Perhaps unsurprisingly, nearly all of the dancers examined here continued dancing on the day of their injury despite experiencing symptoms. The researchers theorized that many dancers, like athletes, may be suffering concussions without recognizing or reporting them. Additionally, dancers are known to attempt to dance through pain, which means that some dancers may also be intentionally continuing to dance despite concussion symptoms. Since many dance-related concussions occur through accidents like collisions and falls, standard safety measures can and should be taken at dance studios and performance venues. The researchers finish up by proposing dance-specific adaptations to the guidelines for concussion management from the 4th International Conference on Concussion in Sport.

Stein CJ, Kinney SA, McCrystal T, et al. Dance-related concussion: A case series. J Dance Med Sci. 2014:18(2):53-61

Research: Trunk Muscle Endurance and Low Back Pain in Female Dance Students

Previous research has suggested that trunk muscles with lowered levels of muscular endurance can predispose an athlete to low back pain. This study sought to examine the exact role that trunk muscle endurance plays in the development of low back pain among female dance students. To achieve this, the researchers had all study participants perform four isometric trunk muscle endurance tests: right side plank, left side plank, double straight leg raise, and the Sorensen test. The study’s participants were female dance students; 11 of the 17 participants had low back pain while the remaining 6 did not. The study found significant differences between groups for both side planks and the double straight leg raise, with the low back pain group recording significantly shorter times on these tests (a shorter time indicated lower levels of muscle endurance). Therefore, it appears that, among female dance students, those with low back pain have lower levels of trunk muscle endurance than those who do not. These findings are consistent with previous literature that identified good isometric endurance of the trunk muscles as a protective mechanism against the development of low back pain. However, the results of this study can only demonstrate association, not causation with respect to lower levels of trunk muscle endurance and the development of low back pain.  It is possible that the dancers' low back pain limited their ability to effectively perform the trunk muscle endurance tests.

Swain C, Redding E. Trunk muscle endurance and low back pain in female dance students. J Dance Med Sci. 2014;18(2):62-66

Research: EMG Comparison of Grand Battement Devant at the Barre, in the Center, and Traveling

In examining trunk and lower extremity muscle usage during a functional dance motion, the researchers used surface EMG electrodes and force plates to study beginner, intermediate-level, and advanced dancers as they performed a grand battement devant at the barre, in center, and while traveling. The researchers had two hypotheses: (1) that trunk and lower extremity muscle use would differ between the 3 conditions (stationary with support, stationary without support, and while moving), and (2) that muscle activation levels would differ by training/experience level of dancers. The movement of the grand battement devant was broken down into 4 distinct phases (or “events”): stance, initiation of movement, peak of movement, and end of motion.

Foot, Ankle, and Lower Leg Pain in Dancers: FHL Tendinopathy

The Flexor Hallucis Longus (FHL) tendon is Harry in the “Tom, Dick, and Harry” grouping of extrinsic foot muscle tendons that pass through the tarsal tunnel. The FHL is responsible for great toe flexion and it assists with plantar flexion of the ankle. While not often inflamed in isolation in the general population or in the athletic population at large, the FHL can very easily become injured in dancers. Most frequently, FHL tendinopathy is caused by repetitive strain, but indirect or direct injury and irritation can result from acute trauma.

Research: A Yoga Intervention for Music Performance Anxiety in Conservatory Students

This pilot study sought to determine the effectiveness of a 9-week yoga program with respect to reducing music performance anxiety among undergraduate and graduate music conservatory students. The 17 subjects who completed the entire study demonstrated decreases in performance anxiety (especially associated with solo performance) and in trait anxiety. Follow up at 7-14 months indicated that the improvements experienced by the program completers were sustained. The positive feedback received from the participants about the program and its effects on general well-being and performance anxiety were encouraging to the authors.