Intra-operative 3D imaging system for robot-assisted fracture manipulation.

Reduction is a crucial step in the treatment of broken bones. Achieving precise anatomical alignment of bone fragments is essential for a good fast healing process. Percutaneous techniques are associated with faster recovery time and lower infection risk. However, deducing intra-operatively the desired reduction position is quite challenging due to the currently available technology. The 2D nature of this technology (i.e. the image intensifier) doesn't provide enough information to the surgeon regarding the fracture alignment and rotation, which is actually a three-dimensional problem. This paper describes the design and development of a 3D imaging system for the intra-operative virtual reduction of joint fractures. The proposed imaging system is able to receive and segment CT scan data of the fracture, to generate the 3D models of the bone fragments, and display them on a GUI. A commercial optical tracker was included into the system to track the actual pose of the bone fragments in the physical space, and generate the corresponding pose relations in the virtual environment of the imaging system. The surgeon virtually reduces the fracture in the 3D virtual environment, and a robotic manipulator connected to the fracture through an orthopedic pin executes the physical reductions accordingly. The system is here evaluated through fracture reduction experiments, demonstrating a reduction accuracy of 1.04 ± 0.69 mm (translational RMSE) and 0.89 ± 0.71 ° (rotational RMSE).

Design and real-time control of a robotic system for fracture manipulation.

This paper presents the design, development and control of a new robotic system for fracture manipulation. The objective is to improve the precision, ergonomics and safety of the traditional surgical procedure to treat joint fractures. The achievements toward this direction are here reported and include the design, the real-time control architecture and the evaluation of a new robotic manipulator system. The robotic manipulator is a 6-DOF parallel robot with the struts developed as linear actuators. The control architecture is also described here. The high-level controller implements a host-target structure composed by a host computer (PC), a real-time controller, and an FPGA. A graphical user interface was designed allowing the surgeon to comfortably automate and monitor the robotic system. The real-time controller guarantees the determinism of the control algorithms adding an extra level of safety for the robotic automation. The system's positioning accuracy and repeatability have been demonstrated showing a maximum positioning RMSE of 1.18 ± 1.14mm (translations) and 1.85 ± 1.54° (rotations).

Axillary artery injury associated with proximal humerus fractures.

Penetrating trauma is the primary cause of upper extremity vascular injury almost in 95% of cases. Blunt trauma due to traffic or industrial accidents and falls account for the remaining 5% to 10%. However axillary artery injury from blunt trauma to the shoulder is extremely rare. The location of the axillary artery, surrounded by the bones and muscles of the shoulder girdle, explains the low incidence of trauma suffered by this arterial segment. But its anatomical proximity to the humeral head makes it quite vulnerable to blunt trauma during shoulder injury. Herein we report two cases of axillary artery injury after proximal humerus fracture, discussing their diagnosis and management.

Acute renal failure due to rhabdomyolysis after proximal humerus fracture associated with axillary artery rupture.

The anatomical proximity of axillary artery to the humeral head makes it quite vulnerable to blunt trauma during shoulder injury. Axillary artery rupture and prolonged ischemia may lead to rhabdomyolysis and acute renal failure. Herein we present a case of a patient who sustained proximal humerus fracture associated with axillary artery rupture and acute renal failure due to rhabdomyolysis.