Upper limb kinematics in functional tasks during standing

The purpose of this thesis is to create a method for analyzing the features of 3D arm movement, along with consequent thorax and pelvis motions, during functional tasks in both healthy controls, comparing their dominant and non-dominant limbs, and in individuals affected by upper limb lymphedema, comparing the affected limb with the unaffected one. Lymphedema is a manifestation of insufficient lymphatic system function, following, in this case, the removal of lymphatic axillary nodes during radical breast surgery. The primary outcome is the swelling of the affected limb, resulting from the accumulation of substances and adipose tissue in the extracellular space. This condition can lead to various complications, including decreased mobility of the shoulder joint. This study involved ten healthy female controls and two female subjects affected by upper limb lymphedema. Participants were instructed to perform six different motion tasks three consecutive times, including elevation in the sagittal plane with both arms, elevation in the scapular plane with both arms, circumduction, frontal reaching, lateral reaching, and upward reaching done with both one and both arms. Kinematic data were collected using a stereophotogrammetric system with retroreflective markers placed on the upper body during the execution of these functional tasks while standing. The proposed method starts by segmenting the movement, distinguishing the three different repetitions, using the data of the markers placed on the lateral epicondyle of both elbows (labelled RELB and LELB). Then the instant of maximum amplitude in the movement is determined. Once the intervals of motion are obtained, for each repetition of the functional task, markers RELB and LELB are used to compute the total path length taken by the arms and the mean velocity of execution. To explore compensatory movement of the thorax in the plane xy, the displacement of the segment linking the markers placed on the acromio-clavicular joints (labelled RSHO and LSHO) between the starting position and the reaching maximum amplitude position is computed, in terms of the area enclosed by the two segments. With the same purpose, but in the yz plane, the elbow's trajectory in the circumduction tasks is plotted in both the laboratory and the thorax coordinate systems. The area enclosed in each curve is computed using the trapezoid method to compare the amplitude of the movement trajectory in the two reference frames. Finally, the angular excursion of the thorax over the pelvis and of the pelvis over the laboratory have been evaluated by computing joint angles with the Grood & Suntay method. Analysis of the results indicates pronounced asymmetry between limbs in patients with upper limb lymphedema across all computed parameters: in terms of path length and velocity, the values gained are always higher for the unaffected limb, and in terms of thorax compensation movements, these are more present when the functional task is executed with the affected limb. Conversely, in healthy controls, differences between dominant and non-dominant arms are generally not statistically significant, except in select cases. Control subjects typically exhibit slightly higher path length values for the dominant arm and higher velocity values for the non-dominant arm. Trunk compensation movements are more pronounced when tasks are executed with the non-dominant arm. Comparing patients with upper limb lymphedema to control subjects, asymmetry between upper limbs is more pronounced in patients, particularly in one of the two patients, with patients consistently exhibiting lower path length and velocity values compared to controls. Therefore, as evidenced by the results, the analysis of upper limb kinematics, with particular attention to trunk compensatory movements, could play a significant role in evaluating the effectiveness of therapy and optimizing it.