Armel Crétual

Robots and Humans have to share the same environment more and more often. In the aim of steering robots in a safe and convenient manner among humans it is required to understand how humans interact with them. This work focuses on collision avoidance between a human and a robot during locomotion. Having in mind previous results on human obstacle avoidance, as well as the description of the main principles which guide collision avoidance strategies, we observe how humans adapt a goal-directed locomotion task when they have to interfere with a mobile robot. Our results show differences in the strategy set by humans to avoid a robot in comparison with avoiding another human. Humans prefer to give the way to the robot even when they are likely to pass first at the beginning of the interaction.

There is a paucity of data detailing management of anterior capsular redundancy (ACR) when using the Latarjet procedure for unidirectional instability. This study aimed to describe the surgical management and to assess the clinical profile of patients presenting with anterior capsular redundancy [ACR(+)] with anterior shoulder instability. Seventy-seven patients who had a Latarjet procedure were followed for a 55-month period. Per-operative ACR was assessed during surgery. ACR was considered present if the inferior capsular flap of a Neer T-shaft capsulorrhaphy was able to cover the superior capsular flap with the arm in the neutral position. Patients with ACR(+) received an additional Neer capsulorrhaphy, while patients with ACR(−) did not. This per-operative finding was correlated with demographics, clinical, radiological pre-operative data and surgical outcome. Patients presenting with a per-operative ACR(+) were significantly associated with a sulcus sign (P < 0.001), a Beighton score >4 (P < 0.01), a low-energy instability history (P < 0.05), a predominant history of subluxations (P < 0.05), fewer Hill–Sachs lesion (P < 0.05) and a female gender (P < 0.05), but not significantly with external rotation >85°. Open standard Latarjet procedures with Neer capsulorrhaphy in ACR(+) patients showed excellent or good results and stability rate of 95 %. All patients except four who presented with a new dislocation after surgery were satisfied with their outcome. Thirteen patients (16 %) had a persistent apprehension sign at the last follow-up. ACR(+) and ACR(−) groups did not show significant difference in the mean values of Rowe, Walch–Duplay and Constant–Murley scores. ACR correlated with a sulcus sign, Beighton score and instability history. In anterior shoulder instability associated with ACR, the Latarjet procedure with a Neer capsulorrhaphy appears a satisfactory treatment alternative to arthroscopic or open capsular shift. It decreased apprehension in comparison with Latarjet procedures without capsular repair. Cases series, treatment study, Level IV.