Quantitative analysis of surgeons’ motor variability during the surgical practice is still scarce. Therefore, a framework for the analysis of surgeon upper-body postural variability during laparoscopic procedures was developed. 3D kinematics analysis gave us information regarding the head posture adopted by the surgeons with respect to the trunk and how this varies during surgical training activities. Furthermore, surgeon’s upper-body joint variability was quantified using the framework of the Uncontrolled Manifold hypothesis, allowing to separate the combination of joint angles that were equally able to stabilize head mean posture on sagittal plane for those solutions that were destabilized head mean posture. The results showed that the underlying framework was able to quantify surgeons’ motor variability, providing inspiration for new human-machine interaction designs, as well as more targeted ergonomics assessments.