Three-dimensional measurement of lumbar spine kinematics for fast bowlers in cricket

Objective. To determine whether the three-dimensional (3-D) lumbar spine kinematics for the mixed fast bowling technique differed to those of the side-on and front-on fast bowling techniques. Background. It has been previously shown that bowlers who utilise a mixed bowling technique are more likely to show lumbar spine pathology than those who bowl with either the side-on or front-on techniques. Methods. An electromagnetic device (3-Space ®Fastrak ™) operating at 120 Hz captured range of motion and 3-D lumbar spine kinematics during the delivery stride of 20 young high performance subjects. The trajectory of shoulder and pelvic girdle markers were simultaneously captured and these data were used to classify bowlers into either a side-on, front-on or mixed technique group. Results. No significant differences ( P < 0.004) existed between the side-on/front-on and mixed groups for 12 selected variables derived from the lumbar spine kinematic data. However, an examination of effect sizes revealed evidence that the mixed group showed: a greater amount of left lateral bend and an extended lumbar spine at front foot impact; a body position further from a neutral orientation at release; and a greater range of motion and angular velocity of the trunk in the lateral bending and flexion/extension axes. Conclusions. Selected lumbar range of motion and velocity measures tended to be higher for mixed bowlers than side-on/front-on bowlers.