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FIGURE 3.46 High range of spinal hyperextension present in some dancers.
TABLE 3.6 Normal Range of Motion and Constraints for Fundamental Movements of the Spine
Spine movement
(thoracic and lumbar)Average ranges
of joint motion* Normal passive limiting factors
Flexion 0-80° Ligaments: posterior spinal ligaments
Discs: compression of anterior aspect and tension of posterior
aspect
Joint capsules: capsules and ligaments of facet joints
Muscles: spinal extensors and associated thoracolumbar fascia
Extension 0-30° Ligament: anterior longitudinal ligament
Discs: compression of posterior aspect and tension of anterior
aspect
Joint capsules: capsules and ligaments of facet joints
Muscles: abdominals
Bony constraints: overlapping of spinous processes in thoracic
region, approximation of facet joints in lumbar region
Lateral flexion 0-35° Ligaments: contralateral spinal ligaments
Discs: compression of ipsilateral portion of disc and tension of
contralateral portion of disc
Joint capsules: capsules and ligaments of facet joints
Muscles: contralateral quadratus lumborum and varying amounts of
oblique abdominals and spinal extensors, depending on position of
torso
Bony constraints: approximation of lower ribs and iliac crest
Rotation 0-45° Ligaments: costovertebral and perhaps posterior ligaments
Discs: tension in annulus fibrosus
Joint capsules: capsules of facet joints
Muscles: oblique abdominals and spinal extensors, varying with
position of torso
Bony constraints: facet joints in lumbar region*From American Academy of Orthopaedic Surgeons (1965).