Motion of the multi-segmented spine in elite dancers during passé and arabesque

BACKGROUND

The spinal biomechanics of dance tasks have received little study and no studies have used a multi-segmented spinal model. Knowledge of how the segments of the spine move may be useful to the dance clinician and dance educator.

RESEARCH QUESTION

What is the direction and amount of motion of the primary segments of the spine in elite dancers during an arabesque and a passé?

METHODS

This observational study examined 59 elite dancers performing an arabesque and a passé using a three-dimensional motion analysis system with the trunk divided into a series of five segments: pelvis, lower lumbar, upper lumbar, lower thoracic and upper thoracic spine.

RESULTS

For the arabesque, all spinal segments moved in the same direction within each plane and the majority of total spinal motion occurred in the thoracic spine. Thoracic segments were at or near end range position at completion of the arabesque. For the passé, the spinal segments moved in different directions within each plane and the majority of total spinal motion occurred in the lumbar spine.

SIGNIFICANCE

Dance clinicians and dance educators may benefit from the knowledge that thoracic hypomobility in any plane may limit arabesque performance and that attempts to instruct dancers to achieve a position of passé without flexion of the lumbar spine may be a valid aesthetic ideal but also an unrealistic functional expectation.

Effects of lower trunk movement in flat-back syndrome during stair climbing: A technical note

OBJECTIVE

This study investigated the differences in trunk sway during stair climbing between people with normal spinal alignment and people with flat-back syndrome.

METHODS

Twelve male volunteers with flat-back syndrome (global angle < 20 degrees) and 12 male volunteers with normal spinal alignment (global angle between 20 degrees and 30 degrees) were enrolled. An accelerator was attached to the third lumbar spine and the sway of each participant's trunk was measured during stair climbing.

RESULT

Participants with flat-back syndrome showed significant differences in vector, anteroposterior sway, and vertical sway of the trunk during stair climbing (p< 0.05). However, mediolateral sway of the trunk and gait time did not significantly differ between groups (p> 0.05).

CONCLUSION

Our findings can be used as baseline data for prevention of back pain. Furthermore, increased trunk sway can cause increased energy usage, leading to inefficient gait. Further research is needed to prevent this problem.

MULTI-SEGMENTED TRUNK MOTION OF HEALTHY NON-ELDERLY ADULTS IN DIFFERENT DECADES OF LIFE

Traditionally, gait analysis models the trunk as one rigid body segment. This approach has limitations; it does not capture all the movements of this area of the body throughout locomotion. Lower-extremity-gait kinematics do not routinely change in healthy non-elderly adults in different decades of life; however, it is unknown if trunk kinematics will be altered during different activities of daily living as a function of age. The purpose of this study was to determine if a previously validated multi-segmented trunk model would detect trunk movement variations in non-elderly healthy adults in different decades of life. Thirty-four non-elderly healthy adults in various decades of life (20-29 years, 30-39 years, 40-49 years, and 50-59 years) completed two tasks of ambulatory daily living (level walking and stair descent). Trunk maximum angle during the gait cycle, timing of the trunk maximum angle during the gait cycle and trunk range of motion were examined using analysis of variance procedures. Findings are that age group did not affect the trunk kinematics of individuals in different decades of life, but that may not represent the experiences of elderly individuals.