Purpose Current surgical robotic systems are either large serial arms, resulting in higher risks due to their high inertia and no inherent limitations of the working space, or they are bone-mounted, adding substantial additional task steps to the surgical workflow. The robot presented in this paper has a handy and lightweight design and can be easily held by the surgeon. No rigid fixation to the bone or a cart is necessary. A high-speed tracking camera together with a fast control system ensures the accurate positioning of a burring tool. Methods The capabilities of the robotic system to dynamically compensate for unintended motion, either of the robot itself or the patient, was evaluated. Therefore, the step response was analyzed as well as the capability to follow a moving target. Results The step response show that the robot can compensate for undesired motions up to 12 Hz in any direction. While following a moving target, a maximum positioning error of 0.5 mm can be obtained with a target motion of up to 18 mm/s. Conclusion The requirements regarding dynamic motion compensation, accuracy, and machining speed of unicompartmental knee arthroplasties, for which the robot was optimized, are achieved with the presented robotic system. In particular, the step response results show that the robot is able to compensate for human tremor.

Craniotomy is part of many neurosurgical interventions to create surgical access to intracranial structures. The procedure conventionally bears a high risk of unintended dural tears or damage of the soft tissue underneath the bone. A new synergistically controlled instrument has recently been introduced to address this problem by combining a soft tissue preserving saw with an automatic cutting depth control. Many approaches are known to obtain the information required on the local bone thickness. However, they suffer from unsatisfactory robustness against disturbances occurring during surgery and many approaches require additional intra- or preoperative steps in the workflow. This article presents first concepts for real-time cutting depth control based on in-process bioimpedance measurements. Furthermore, sensor integration into a synergistic surgical device incorporating a bidirectional oscillating saw is demonstrated and evaluated in first feasibility tests on a fresh bovine bone specimen. Results of bipolar measurements show that the transition of different layers of bicortical bone and bone breakthrough lead to characteristic impedance patterns that can be used for process control.

Modern operating rooms (OR) undergo a constant rise in the amount and complexity of technical systems. Due to a lack of inter-device communication and integration, each device works stand-alone resulting in redundant sensors, input devices, monitors and-last but not least-crowded ORs and error prone humanmachine-interaction. Therefore, various manufacturers such as Brainlab and Karl Storz provide proprietary integrated workstations. However, those "monolithic" solutions restrict the flexibility of the users and the clinical operators regarding integration of innovative third party devices.In view of this, the OR.NET initiative (www.ornet.org) strives to develop international open standards for secure dynamic networks of medical devices in ORs. In the scope of the OR.NET project, based on service oriented architecture (SOA), the SDC (Service-oriented Device Connectivity) approach is currently in the process of standardization under IEEE 11073 to link medical devices in the OR (short OR.NETwork). It paves the way to interoperability between various medical devices due to its independence of license holders.However, the SDC network does not suit real time (RT) requirements of a deterministic data transmission and low maximum latency, e.g. for robotic applications. This paper shows an approach to extend the secure dynamic OR by a real-time capable network to allow the integration of robotic systems. Exemplarily, this paper outlines an orthopaedic robotic system that is released by a universal configurable footswitch. This significantly extends the scope of applications for integrated ORs with the IEEE 11073 standard.

Currently, there are only a small number of robotic systems used in various surgical fields. As modified industrial robot systems have shown significant limitations in the past, specialized kinematic solutions have been proposed for specific surgical applications. The majority of these systems are designed for specific applications in only a limited number of cases. The acquisition and operating costs are high, hindering the dissemination and broad clinical application of such systems. To address this problem, a modular mini-robot system is proposed, which can be easily adapted to different application-specific requirements. Therefore, the requirements of different applications have been categorized and clustered to a standardized requirement profile. Next, a modular robot based on a hybrid kinematic module structure has been developed. This concept has been implemented and tested in in vitro studies for different applications, such as revision total hip replacement and unicondylar knee arthroplasty. User-orientated tests of the intraoperative handling, as well as accuracy tests, proved the feasibility of the concept.

Zusammenfassung Um den Chirurgen bei der Eröffnung des Schädels in der Neurochirurgie oder des Brustbeins in der Herz-und Thoraxchirurgie zu unterstützen, wurde ein semiautomatisches, handgeführtes Sägeinstrument entwickelt. Die Schnitttiefe wird auf Basis von drei unterschiedlichen Messverfahren (Computertomographie, Ultraschall, Licht) automatisch geregelt. Nach erfolgreichen Machbarkeitsstudien zu den einzelnen Ansätzen wird in diesem Beitrag darauf aufbauend ein detaillierter Vergleich der Verfahren mit einer Untersuchung der strukturellen Vor-und Nachteile sowie Optimierungspotentiale durchgeführt.Summary To support the surgeon during opening of the skull in neurosurgery or of the sternum in cardiothoracic surgery, a semiautomatic, hand guided saw was developed. The cutting depth is automatically controlled on the basis of three different modalities (computed tomography, ultrasound, light). In addition to the general successful proof of general feasibility, the present paper provides the results of a detailed comparison of the different systems in combination with an analysis of the structural advantages and disadvantages and their individual optimization potential.